@article{10128, abstract = {An extensive computational study of the conformational preferences of three capped dipeptides: Ac-Xxx-Phe-NH2, Xxx = Gly, Ala, Val is reported. On the basis of local second-order Møller–Plesset perturbation theory (LMP2) and DFT computations we were able to identify the experimentally observed conformers as γL–γL(g−) and β-turn I(g+) in Ac-Gly-Phe-NH2, and Ac-Ala-Phe-NH2, and as the closely related γL(g+)–γL(g−) and β-turn I(a,g+) in Ac-Val-Phe-NH2. In contrast to the experimental observation that peptides with bulky side chain have a propensity for β-turns, we show that in Ac-Val-Phe-NH2 the minimum energy structure corresponds to the experimentally non detected β-strand.}, author = {Šarić, Anđela and Hrenar, T. and Mališ, M. and Došlić, N.}, issn = {1463-9076}, journal = {Physical Chemistry Chemical Physics}, keywords = {Physical and Theoretical Chemistry, General Physics and Astronomy}, number = {18}, pages = {4678--4685}, publisher = {Royal Society of Chemistry }, title = {{Quantum mechanical study of secondary structure formation in protected dipeptides}}, doi = {10.1039/b923041f}, volume = {12}, year = {2010}, } @article{10127, abstract = {We use numerical simulations to show how noninteracting hard particles binding to a deformable elastic shell may self-assemble into a variety of linear patterns. This is a result of the nontrivial elastic response to deformations of shells. The morphology of the patterns can be controlled by the mechanical properties of the surface, and can be fine-tuned by varying the binding energy of the particles. We also repeat our calculations for a fully flexible chain and find that the chain conformations follow patterns similar to those formed by the nanoparticles under analogous conditions. We propose a simple way of understanding and sorting the different structures and relate it to the underlying shape transition of the shell. Finally, we discuss the implications of our results.}, author = {Šarić, Anđela and Cacciuto, Angelo}, issn = {1744-683X}, journal = {Soft Matter}, keywords = {condensed matter physics, general chemistry}, number = {5}, pages = {1874--1878}, publisher = {Royal Society of Chemistry (RSC)}, title = {{Particle self-assembly on soft elastic shells}}, doi = {10.1039/c0sm01143f}, volume = {7}, year = {2010}, } @article{10390, abstract = {We use numerical simulations to study the phase behavior of a system of purely repulsive soft dumbbells as a function of size ratio of the two components and their relative degree of deformability. We find a plethora of different phases, which includes most of the mesophases observed in self-assembly of block copolymers but also crystalline structures formed by asymmetric, hard binary mixtures. Our results detail the phenomenological behavior of these systems when softness is introduced in terms of two different classes of interparticle interactions: (a) the elastic Hertz potential, which has a finite energy cost for complete overlap of any two components, and (b) a generic power-law repulsion with tunable exponent. We discuss how simple geometric arguments can be used to account for the large structural variety observed in these systems and detail the similarities and differences in the phase behavior for the two classes of potentials under consideration.}, author = {Šarić, Anđela and Bozorgui, Behnaz and Cacciuto, Angelo}, issn = {1520-5207}, journal = {The Journal of Physical Chemistry B}, keywords = {materials chemistry}, number = {22}, pages = {7182--7189}, publisher = {American Chemical Society}, title = {{Packing of soft asymmetric dumbbells}}, doi = {10.1021/jp107545w}, volume = {115}, year = {2010}, } @article{10391, abstract = {We use numerical simulations to show how a fully flexible filament binding to a deformable cylindrical surface may acquire a macroscopic persistence length and a helical conformation. This is a result of the nontrivial elastic response to deformations of elastic sheets. We find that the filament’s helical pitch is completely determined by the mechanical properties of the surface, and can be easily tuned by varying the surface stretching rigidity. We propose simple scaling arguments to understand the physical mechanism behind this phenomenon and present a phase diagram indicating under what conditions one should expect a fully flexible chain to behave as a helical semiflexible filament. Finally, we discuss the implications of our results.}, author = {Šarić, Anđela and Pàmies, Josep C. and Cacciuto, Angelo}, issn = {1079-7114}, journal = {Physical Review Letters}, keywords = {general physics and astronomy}, number = {22}, publisher = {American Physical Society}, title = {{Effective elasticity of a flexible filament bound to a deformable cylindrical surface}}, doi = {10.1103/physrevlett.104.226101}, volume = {104}, year = {2010}, } @inproceedings{1042, abstract = {Recent years have seen tremendous progress in the field of cold and ultracold molecules. A central goal in the field is currently the realization of stable rovibronic ground-state molecular samples in the regime of quantum degeneracy, e.g. in the form of molecular Bose-Einstein condensates, molecular degenerate Fermi gases, or, when an optical lattice is present, molecular Mott-insulator phases. However, molecular samples are not readily cooled to the extremely low temperatures at which quantum degeneracy occurs. In particular, laser cooling, the \'workhorse\' for the field of atomic quantum gases, is generally not applicable to molecular samples. Here we take an important step beyond previous work1 and provide details on the realization of an ultracold quantum gas of ground-state dimer molecules trapped in an optical lattice as recently reported in Ref. 2. We demonstrate full control over all internal and external quantum degrees of freedom for the ground-state molecules by deterministically preparing the molecules in a single quantum state, i.e. in a specific hyperfine sublevel of the rovibronic ground state, while the molecules are trapped in the motional ground state of the individual lattice wells. We circumvent the problem of cooling by associating weakly-bound molecules out of a zero-temperature atomic Mott-insulator state and by transferring these to the absolute ground state in a four-photon STIRAP process. Our preparation procedure directly leads to a long-lived, lattice-trapped molecular many-body state, which we expect to form the platform for many of the envisioned future experiments with molecular quantum gases, e.g. on precision molecular spectroscopy, quantum information science, and dipolar quantum systems.}, author = {Danzl, Johann G and Mark, Manfred and Haller, Elmar and Gustavsson, Mattias and Hart, Russell and Nägerl, Hanns}, pages = {256 -- 269}, publisher = {World Scientific Publishing}, title = {{Production of a quantum gas of rovibronic ground-state molecules in an optical lattice}}, doi = {10.1142/9789814282345_0024}, year = {2010}, } @article{1044, abstract = {Control over all internal and external degrees of freedom of molecules at the level of single quantum states will enable a series of fundamental studies in physics and chemistry1,2. In particular, samples of ground-state molecules at ultralow temperatures and high number densities will facilitate new quantum-gas studies3 and future applications in quantum information science4. However, high phase-space densities for molecular samples are not readily attainable because efficient cooling techniques such as laser cooling are lacking. Here we produce an ultracold and dense sample of molecules in a single hyperfine level of the rovibronic ground state with each molecule individually trapped in the motional ground state of an optical lattice well. Starting from a zero-temperature atomic Mott-insulator state with optimized double-site occupancy6, weakly bound dimer molecules are efficiently associated on a Feshbach resonance7 and subsequently transferred to the rovibronic ground state by a stimulated four-photon process with >50% efficiency. The molecules are trapped in the lattice and have a lifetime of 8 s. Our results present a crucial step towards Bose-Einstein condensation of ground-state molecules and, when suitably generalized to polar heteronuclear molecules, the realization of dipolar quantum-gas phases in optical lattices8-10.}, author = {Danzl, Johann G and Mark, Manfred and Haller, Elmar and Gustavsson, Mattias and Hart, Russell and Aldegunde, Jesus and Hutson, Jeremy and Nägerl, Hanns}, journal = {Nature Physics}, number = {4}, pages = {265 -- 270}, publisher = {Nature Publishing Group}, title = {{An ultracold high-density sample of rovibronic ground-state molecules in an optical lattice}}, doi = {10.1038/nphys1533}, volume = {6}, year = {2010}, } @article{1045, abstract = {We report on the observation of confinement-induced resonances in strongly interacting quantum-gas systems with tunable interactions for one- and two-dimensional geometry. Atom-atom scattering is substantially modified when the s-wave scattering length approaches the length scale associated with the tight transversal confinement, leading to characteristic loss and heating signatures. Upon introducing an anisotropy for the transversal confinement we observe a splitting of the confinement-induced resonance. With increasing anisotropy additional resonances appear. In the limit of a two-dimensional system we find that one resonance persists.}, author = {Haller, Elmar and Mark, Manfred and Hart, Russell and Danzl, Johann G and Reichsöllner, Lukas and Melezhik, Vladimir and Schmelcher, Peter and Nägerl, Hanns}, journal = {Physical Review Letters}, number = {15}, publisher = {American Physical Society}, title = {{Confinement-induced resonances in low-dimensional quantum systems}}, doi = {10.1103/PhysRevLett.104.153203}, volume = {104}, year = {2010}, } @article{1049, abstract = {Quantum many-body systems can have phase transitions even at zero temperature; fluctuations arising from Heisenbergĝ€™s uncertainty principle, as opposed to thermal effects, drive the system from one phase to another. Typically, during the transition the relative strength of two competing terms in the systemĝ€™s Hamiltonian changes across a finite critical value. A well-known example is the Mottĝ€" Hubbard quantum phase transition from a superfluid to an insulating phase, which has been observed for weakly interacting bosonic atomic gases. However, for strongly interacting quantum systems confined to lower-dimensional geometry, a novel type of quantum phase transition may be induced and driven by an arbitrarily weak perturbation to the Hamiltonian. Here we observe such an effectĝ€"the sineĝ€"Gordon quantum phase transition from a superfluid Luttinger liquid to a Mott insulatorĝ€ "in a one-dimensional quantum gas of bosonic caesium atoms with tunable interactions. For sufficiently strong interactions, the transition is induced by adding an arbitrarily weak optical lattice commensurate with the atomic granularity, which leads to immediate pinning of the atoms. We map out the phase diagram and find that our measurements in the strongly interacting regime agree well with a quantum field description based on the exactly solvable sineĝ€"Gordon model. We trace the phase boundary all the way to the weakly interacting regime, where we find good agreement with the predictions of the one-dimensional Boseĝ€"Hubbard model. Our results open up the experimental study of quantum phase transitions, criticality and transport phenomena beyond Hubbard-type models in the context of ultracold gases.}, author = {Haller, Elmar and Hart, Russell and Mark, Manfred and Danzl, Johann G and Reichsöllner, Lukas and Gustavsson, Mattias and Dalmonte, Marcello and Pupillo, Guido and Nägerl, Hanns}, journal = {Nature}, number = {7306}, pages = {597 -- 600}, publisher = {Nature Publishing Group}, title = {{Pinning quantum phase transition for a Luttinger liquid of strongly interacting bosons}}, doi = {10.1038/nature09259}, volume = {466}, year = {2010}, } @article{1047, abstract = {Particles in a perfect lattice potential perform Bloch oscillations when subject to a constant force, leading to localization and preventing conductivity. For a weakly interacting Bose-Einstein condensate of Cs atoms, we observe giant center-of-mass oscillations in position space with a displacement across hundreds of lattice sites when we add a periodic modulation to the force near the Bloch frequency. We study the dependence of these "super" Bloch oscillations on lattice depth, modulation amplitude, and modulation frequency and show that they provide a means to induce linear transport in a dissipation-free lattice.}, author = {Haller, Elmar and Hart, Russell and Mark, Manfred and Danzl, Johann G and Reichsöllner, Lukas and Nägerl, Hanns}, journal = {Physical Review Letters}, number = {20}, publisher = {American Physical Society}, title = {{Inducing transport in a dissipation-free lattice with super bloch oscillations}}, doi = {10.1103/PhysRevLett.104.200403}, volume = {104}, year = {2010}, } @article{1046, abstract = {The phenomenon of matter-wave interference lies at the heart of quantum physics. It has been observed in various contexts in the limit of non-interacting particles as a single-particle effect. Here we observe and control matter-wave interference whose evolution is driven by interparticle interactions. In a multi-path matter-wave interferometer, the macroscopic manybody wave function of an interacting atomic Bose-Einstein condensate develops a regular interference pattern, allowing us to detect and directly visualize the effect of interaction-induced phase shifts. We demonstrate control over the phase evolution by inhibiting interaction-induced dephasing and by refocusing a dephased macroscopic matter wave in a spin-echo-type experiment. Our results show that interactions in a many-body system lead to a surprisingly coherent evolution, possibly enabling narrow-band and high-brightness matterwave interferometers based on atom lasers.}, author = {Gustavsson, Mattias and Haller, Elmar and Mark, Manfred and Danzl, Johann G and Hart, Russell and Daley, Andrew and Nägerl, Hanns}, journal = {New Journal of Physics}, publisher = {IOP Publishing Ltd.}, title = {{Interference of interacting matter waves}}, doi = {10.1088/1367-2630/12/6/065029}, volume = {12}, year = {2010}, } @inproceedings{10908, abstract = {We present ABC, a software tool for automatically computing symbolic upper bounds on the number of iterations of nested program loops. The system combines static analysis of programs with symbolic summation techniques to derive loop invariant relations between program variables. Iteration bounds are obtained from the inferred invariants, by replacing variables with bounds on their greatest values. We have successfully applied ABC to a large number of examples. The derived symbolic bounds express non-trivial polynomial relations over loop variables. We also report on results to automatically infer symbolic expressions over harmonic numbers as upper bounds on loop iteration counts.}, author = {Blanc, Régis and Henzinger, Thomas A and Hottelier, Thibaud and Kovács, Laura}, booktitle = {Logic for Programming, Artificial Intelligence, and Reasoning}, editor = {Clarke, Edmund M and Voronkov, Andrei}, isbn = {9783642175107}, issn = {1611-3349}, location = {Dakar, Senegal}, pages = {103--118}, publisher = {Springer Nature}, title = {{ABC: Algebraic Bound Computation for loops}}, doi = {10.1007/978-3-642-17511-4_7}, volume = {6355}, year = {2010}, } @article{11097, abstract = {The nuclear envelope (NE) is a highly regulated membrane barrier that separates the nucleus from the cytoplasm in eukaryotic cells. It contains a large number of different proteins that have been implicated in chromatin organization and gene regulation. Although the nuclear membrane enables complex levels of gene expression, it also poses a challenge when it comes to cell division. To allow access of the mitotic spindle to chromatin, the nucleus of metazoans must completely disassemble during mitosis, generating the need to re-establish the nuclear compartment at the end of each cell division. Here, I summarize our current understanding of the dynamic remodeling of the NE during the cell cycle.}, author = {HETZER, Martin W}, issn = {1943-0264}, journal = {Cold Spring Harbor Perspectives in Biology}, keywords = {General Biochemistry, Genetics and Molecular Biology}, number = {3}, pages = {a000539--a000539}, publisher = {Cold Spring Harbor Laboratory}, title = {{The nuclear envelope}}, doi = {10.1101/cshperspect.a000539}, volume = {2}, year = {2010}, } @article{11099, abstract = {Nuclear pore complexes (NPCs) serve as transport channels across the nuclear membrane, a double lipid bilayer that physically separates the nucleoplasm and cytoplasm of eukaryotic cells. New evidence suggests that the multiprotein nuclear pores also play a role in chromatin organization and gene expression. Given the importance of NPC function, it is not surprising that a growing list of human diseases and developmental defects have been linked to its malfunction. In order to fully understand the functional repertoire of NPCs and their essential role for nuclear organization, it is critical to determine the sequence of events that lead to the formation of nuclear pores. This is particularly relevant since NPC number, and possibly composition, are tightly linked to metabolic activity. Most of our knowledge is derived from NPC formation that occurs in dividing cells at the end of mitosis when the nuclear envelope (NE) and NPCs reform from disassembled precursors. However, NPC assembly also takes place during interphase into an intact NE. Importantly, this process is not restricted to dividing cells but also occurs during cell differentiation. Here, we will review aspects unique to this process, namely the regulation of nuclear expansion and the mechanisms of fusion between the outer and inner nuclear membranes. We will then discuss conserved and diverging mechanisms between post-mitotic and interphase assembly of the proteinaceous structure in light of recently published data.}, author = {Doucet, Christine M. and HETZER, Martin W}, issn = {1432-0886}, journal = {Chromosoma}, keywords = {Genetics (clinical), Genetics}, pages = {469--477}, publisher = {Springer Nature}, title = {{Nuclear pore biogenesis into an intact nuclear envelope}}, doi = {10.1007/s00412-010-0289-2}, volume = {119}, year = {2010}, } @article{11102, abstract = {Nuclear pore complexes have recently been shown to play roles in gene activation; however their potential involvement in metazoan transcription remains unclear. Here we show that the nucleoporins Sec13, Nup98, and Nup88, as well as a group of FG-repeat nucleoporins, bind to the Drosophila genome at functionally distinct loci that often do not represent nuclear envelope contact sites. Whereas Nup88 localizes to silent loci, Sec13, Nup98, and a subset of FG-repeat nucleoporins bind to developmentally regulated genes undergoing transcription induction. Strikingly, RNAi-mediated knockdown of intranuclear Sec13 and Nup98 specifically inhibits transcription of their target genes and prevents efficient reactivation of transcription after heat shock, suggesting an essential role of NPC components in regulating complex gene expression programs of multicellular organisms.}, author = {Capelson, Maya and Liang, Yun and Schulte, Roberta and Mair, William and Wagner, Ulrich and HETZER, Martin W}, issn = {0092-8674}, journal = {Cell}, keywords = {General Biochemistry, Genetics and Molecular Biology}, number = {3}, pages = {372--383}, publisher = {Elsevier}, title = {{Chromatin-bound nuclear pore components regulate gene expression in higher eukaryotes}}, doi = {10.1016/j.cell.2009.12.054}, volume = {140}, year = {2010}, } @article{11101, abstract = {In metazoa, nuclear pore complexes (NPCs) assemble from disassembled precursors into a reforming nuclear envelope (NE) at the end of mitosis and into growing intact NEs during interphase. Here, we show via RNAi-mediated knockdown that ELYS, a nucleoporin critical for the recruitment of the essential Nup107/160 complex to chromatin, is required for NPC assembly at the end of mitosis but not during interphase. Conversely, the transmembrane nucleoporin POM121 is critical for the incorporation of the Nup107/160 complex into new assembly sites specifically during interphase. Strikingly, recruitment of the Nup107/160 complex to an intact NE involves a membrane curvature-sensing domain of its constituent Nup133, which is not required for postmitotic NPC formation. Our results suggest that in organisms with open mitosis, NPCs assemble via two distinct mechanisms to accommodate cell cycle-dependent differences in NE topology.}, author = {Doucet, Christine M. and Talamas, Jessica A. and HETZER, Martin W}, issn = {0092-8674}, journal = {Cell}, keywords = {General Biochemistry, Genetics and Molecular Biology}, number = {6}, pages = {1030--1041}, publisher = {Elsevier}, title = {{Cell cycle-dependent differences in nuclear pore complex assembly in metazoa}}, doi = {10.1016/j.cell.2010.04.036}, volume = {141}, year = {2010}, } @article{11098, author = {HETZER, Martin W}, issn = {1945-4589}, journal = {Aging}, keywords = {Cell Biology, Aging}, number = {2}, pages = {74--75}, publisher = {Impact Journals}, title = {{The role of the nuclear pore complex in aging of post-mitotic cells}}, doi = {10.18632/aging.100125}, volume = {2}, year = {2010}, } @inproceedings{11753, abstract = {Ferroelectric ceramic materials have a wide range of applications because of their piezoelectric and pyroelectric properties. One of their most important physical properties is the specific heat. In this study, the specific heats of a series of lead-zirconate-titanate (PZT) compositions in the vicinity of the morphotropic phase boundary (MPB) were measured. The temperature range was from 1.8 to 300 K. It is believed that these are the lowest temperature measurements ever made on PZT. Differences between the specific heats of the different compositions were very small. However, the calculated Debye temperatures were slightly different. The results are useful in computing design parameters for technical devices.}, author = {Lang, S. B. and Lashley, J. C. and Modic, Kimberly A and Fisher, R. A. and Zhu, W. M. and Ye, Z. G.}, booktitle = {Proceedings of the 2010 IEEE International Conference on Solid Dielectrics}, issn = {2159-1687}, location = {Potsdam, Germany}, publisher = {Institute of Electrical and Electronics Engineers}, title = {{Specific heat of a ferroelectric PZT ceramic at the morphotropic phase boundary}}, doi = {10.1109/icsd.2010.5568033}, year = {2010}, } @inproceedings{11754, abstract = {Ferroelectric ceramic materials have a wide range of applications because of their piezoelectric and pyroelectric properties. One of their most important physical properties is the specific heat. In this study, the specific heats of a series of lead-zirconate-titanate (PZT) compositions in the vicinity of the morphotropic phase boundary (MPB) were measured. The temperature range was from 1.8 to 300 K. It is believed that these are the lowest temperature measurements ever made on PZT. Differences between the specific heats of the different compositions were very small. However, the calculated Debye temperatures were slightly different. The results are useful in computing design parameters for technical devices.}, author = {Lang, S.B. and Lashley, J.C. and Modic, Kimberly A and Fisher, R.A. and Zhu, W.M. and Ye, Z.G.}, booktitle = {15th IEEE Mediterranean Electrotechnical Conference}, isbn = {978-142445795-3}, location = {Valletta, Malta}, publisher = {Institute of Electrical and Electronics Engineers}, title = {{Specific heat of a ferroelectric PZT ceramic at the morphotropic phase boundary}}, doi = {10.1109/melcon.2010.5476345}, year = {2010}, } @inproceedings{11797, abstract = {Inspired by online ad allocation, we study online stochastic packing integer programs from theoretical and practical standpoints. We first present a near-optimal online algorithm for a general class of packing integer programs which model various online resource allocation problems including online variants of routing, ad allocations, generalized assignment, and combinatorial auctions. As our main theoretical result, we prove that a simple dual training-based algorithm achieves a (1 − o(1))-approximation guarantee in the random order stochastic model. This is a significant improvement over logarithmic or constant-factor approximations for the adversarial variants of the same problems (e.g. factor 1−1𝑒 for online ad allocation, and log(m) for online routing). We then focus on the online display ad allocation problem and study the efficiency and fairness of various training-based and online allocation algorithms on data sets collected from real-life display ad allocation system. Our experimental evaluation confirms the effectiveness of training-based algorithms on real data sets, and also indicates an intrinsic trade-off between fairness and efficiency.}, author = {Feldman, Jon and Henzinger, Monika H and Korula, Nitish and Mirrokni, Vahab S. and Stein, Cliff}, booktitle = {18th Annual European Symposium on Algorithms}, isbn = {3642157742}, issn = {1611-3349}, location = {Liverpool, United Kingdom}, pages = {182–194}, publisher = {Springer Nature}, title = {{Online stochastic packing applied to display ad allocation}}, doi = {10.1007/978-3-642-15775-2_16}, volume = {6346}, year = {2010}, } @inproceedings{11798, abstract = {Starting with two models fifty years ago, the discrete marriage game [1] and the continuous assignment game [2], the study of stable matchings has evolved into a rich theory with applications in many areas. Most notably, it has lead to a number of truthful mechanisms that have seen a recent rejuvenation in the context of sponsored search. In this paper we survey the history of these problems and provide several links to ongoing research in the field.}, author = {Dütting, Paul and Henzinger, Monika H}, booktitle = {7th International Conference on Algorithms and Complexity}, isbn = {9783642130724}, issn = {1611-3349}, location = {Rome, Italy}, pages = {6–12}, publisher = {Springer Nature}, title = {{Mechanisms for the marriage and the assignment game}}, doi = {10.1007/978-3-642-13073-1_2}, volume = {6078}, year = {2010}, } @inproceedings{11838, abstract = {Two-sided matching markets play a prominent role in economic theory. A prime example of such a market is the sponsored search market where $n$ advertisers compete for the assignment of one of $k$ sponsored search results, also known as ``slots'', for certain keywords they are interested in. Here, as in other markets of that kind, market equilibria correspond to stable matchings. In this paper, we show how to modify Kuhn's Hungarian Method (Kuhn, 1955) so that it finds an optimal stable matching between advertisers and advertising slots in settings with generalized linear utilities, per-bidder-item reserve prices, and per-bidder-item maximum prices. The only algorithm for this problem presented so far (Aggarwal et al., 2009) requires the market to be in ''general position''. We do not make this assumption.}, author = {Dütting, Paul and Henzinger, Monika H and Weber, Ingmar}, booktitle = {27th International Symposium on Theoretical Aspects of Computer Science}, isbn = {978-3-939897-16-3}, issn = {1868-8969}, location = {Nancy, France}, pages = {287--298}, publisher = {Schloss Dagstuhl - Leibniz-Zentrum für Informatik}, title = {{Sponsored search, market equilibria, and the Hungarian Method}}, doi = {10.4230/LIPICS.STACS.2010.2463}, volume = {5}, year = {2010}, } @inproceedings{11863, abstract = {Suppose you buy a new laptop and, simply because you like it so much, you recommend it to friends, encouraging them to purchase it as well. What would be an adequate price for the vendor of the laptop to pay for your recommendation? Personal recommendations like this are of considerable commercial interest, but unlike in sponsored search auctions there can be no truthful prices. Despite this "lack of truthfulness" the vendor of the product might still decide to pay you for recommendation e.g. because she wants to (i) provide you with an additional incentive to actually recommend her or to (ii) increase your satisfaction and/or brand loyalty. This leads us to investigate a pricing scheme based on the Shapley value [5] that satisfies certain "axioms of fairness". We find that it is vulnerable to manipulations and show how to overcome these difficulties using the anonymity-proof Shapley value of [4].}, author = {Dütting, Paul and Henzinger, Monika H and Weber, Ingmar}, booktitle = {Proceedings of the 19th international conference on World wide web }, isbn = {9781605587998}, location = {Raleigh, NC, United States}, pages = {1085--1086}, publisher = {Association for Computing Machinery}, title = {{How much is your personal recommendation worth?}}, doi = {10.1145/1772690.1772816}, year = {2010}, } @article{11885, abstract = {Over the last years the h-index has gained popularity as a measure for comparing the impact of scientists. We investigate if ranking according to the h-index is stable with respect to (i) different choices of citation databases, (ii) normalizing citation counts by the number of authors or by removing self-citations, (iii) small amounts of noise created by randomly removing citations or publications and (iv) small changes in the definition of the index. In experiments for 5,283 computer scientists and 1,354 physicists we show that although the ranking of the h-index is stable under most of these changes, it is unstable when different databases are used. Therefore, comparisons based on the h-index should only be trusted when the rankings of multiple citation databases agree.}, author = {Henzinger, Monika H and Suñol, Jacob and Weber, Ingmar}, issn = {1588-2861}, journal = {Scientometrics}, number = {2}, pages = {465--479}, publisher = {Springer Nature}, title = {{The stability of the h-index}}, doi = {10.1007/s11192-009-0098-7}, volume = {84}, year = {2010}, } @article{11975, abstract = {A new method was developed for the quantitative analysis of steryl glycosides in biodiesel (fatty acid methyl esters). This method is much more sensitive than existing methods and has minimum limits of quantification of 50 μg/kg, compared to previously published minimum limits of quantification of about 15 mg/kg. The analysis is based on gas chromatography–mass spectroscopy determination of simple pre-treated and silylated samples via single ion monitoring at 147, 204, 217 m/z, which are specific ions for the silylated sugar moiety. Quantification was carried out using cholesteryl β-d-glucopyranoside as internal standard. The modified synthesis and purification of the internal standard is also presented as well as the characterization by NMR and mass spectroscopy. The advantage of the method compared with other approaches is the simplified sample preparation avoiding extra pre-treatment steps coupled with complete derivatization of the sugar hydroxyl groups by using N,O-bis(trimethylsilyl)acetamide with 5% trimethylchlorosilane as derivatization reagent. On the given conditions high recovery rates ≥89% can be obtained. Evaluation of lab specific variance and intermediate precision underline the robustness of the method which will be further assessed by Round robin tests.}, author = {Pieber, Bartholomäus and Schober, Sigurd and Goebl, Christoph and Mittelbach, Martin}, issn = {0021-9673}, journal = {Journal of Chromatography A}, number = {42}, pages = {6555--6561}, publisher = {Elsevier}, title = {{Novel sensitive determination of steryl glycosides in biodiesel by gas chromatography-mass spectroscopy}}, doi = {10.1016/j.chroma.2010.08.006}, volume = {1217}, year = {2010}, } @article{12653, abstract = {Daily streamflow from stations close to five Swiss glaciers is analyzed for trends with the Mann-Kendall test. We consider a common period of record (1974–2004) and longer periods based on data availability. The trend statistical significance is tested on annual and seasonal bases. We also examine changes in precipitation, temperature, and snow cover characteristics. Highly glacierized basins show statistically significant positive trends in annual streamflow caused by increasing streamflow in spring and summer. Trends are more numerous and stronger at lower and mid than at the upper quantiles. The basin characterized by lower glacier coverage, conversely, does not exhibit consistently statistically significant trends. Changes in precipitation are not sufficient to explain the observed streamflow trends. Air temperature sees an increase in mean, minimum, and maximum values at all sites. Variations in the seasonal snow accumulation and ablation process are evident. Solid precipitation is decreasing at all sites and trends may be due to a shift from snowfall into rainfall. Mean snow depth is also decreasing, and its duration is getting shorter because of a decrease in solid precipitation and enhanced melting. Trend magnitude attenuates with longer time series. Contrasting trends are detected for different subperiods in the last 70 years: statistically significant negative trends are observed in the periods 1944–1974 and 1954–1984 for Aletschgletscher, in contrast with the results for the common period. These trends are explained by different rates of ice volume changes, and the sign of trends is clearly related to phases of positive or negative glacier mass balance.}, author = {Pellicciotti, Francesca and Bauder, A. and Parola, M.}, issn = {1944-7973}, journal = {Water Resources Research}, keywords = {Water Science and Technology}, number = {10}, publisher = {American Geophysical Union}, title = {{Effect of glaciers on streamflow trends in the Swiss Alps}}, doi = {10.1029/2009wr009039}, volume = {46}, year = {2010}, } @article{1301, abstract = {Motion vision is essential for navigating through the environment. Due to its genetic amenability, the fruit fly Drosophila has been serving for a lengthy period as a model organism for studying optomotor behavior as elicited by large-field horizontal motion. However, the neurons underlying the control of this behavior have not been studied in Drosophila so far. Here we report the first whole cell recordings from three cells of the horizontal system (HSN, HSE, and HSS) in the lobula plate of Drosophila. All three HS cells are tuned to large-field horizontal motion in a direction-selective way; they become excited by front-to-back motion and inhibited by back-to-front motion in the ipsilateral field of view. The response properties of HS cells such as contrast and velocity dependence are in accordance with the correlation-type model of motion detection. Neurobiotin injection suggests extensive coupling among ipsilateral HS cells and additional coupling to tangential cells that have their dendrites in the contralateral hemisphere of the brain. This connectivity scheme accounts for the complex layout of their receptive fields and explains their sensitivity both to ipsilateral and to contralateral motion. Thus the main response properties of Drosophila HS cells are strikingly similar to the responses of their counterparts in the blowfly Calliphora, although we found substantial differences with respect to their dendritic structure and connectivity. This long-awaited functional characterization of HS cells in Drosophila provides the basis for the future dissection of optomotor behavior and the underlying neural circuitry by combining genetics, physiology, and behavior.}, author = {Schnell, Bettina and Jösch, Maximilian A and Förstner, Friedrich and Raghu, Shamprasad and Otsuna, Hideo and Ito, Kei and Borst, Alexander and Reiff, Dierk}, issn = {1522-1598}, journal = {Journal of Neurophysiology}, number = {3}, pages = {1646 -- 1657}, publisher = {American Physiological Society}, title = {{Processing of horizontal optic flow in three visual interneurons of the Drosophila brain}}, doi = {10.1152/jn.00950.2009}, volume = {103}, year = {2010}, } @article{1300, abstract = {Motion vision is a major function of all visual systems, yet the underlying neural mechanisms and circuits are still elusive. In the lamina, the first optic neuropile of Drosophila melanogaster, photoreceptor signals split into five parallel pathways, L1-L5. Here we examine how these pathways contribute to visual motion detection by combining genetic block and reconstitution of neural activity in different lamina cell types with whole-cell recordings from downstream motion-sensitive neurons. We find reduced responses to moving gratings if L1 or L2 is blocked; however, reconstitution of photoreceptor input to only L1 or L2 results in wild-type responses. Thus, the first experiment indicates the necessity of both pathways, whereas the second indicates sufficiency of each single pathway. This contradiction can be explained by electrical coupling between L1 and L2, allowing for activation of both pathways even when only one of them receives photoreceptor input. A fundamental difference between the L1 pathway and the L2 pathway is uncovered when blocking L1 or L2 output while presenting moving edges of positive (ON) or negative (OFF) contrast polarity: blocking L1 eliminates the response to moving ON edges, whereas blocking L2 eliminates the response to moving OFF edges. Thus, similar to the segregation of photoreceptor signals in ON and OFF bipolar cell pathways in the vertebrate retina, photoreceptor signals segregate into ON-L1 and OFF-L2 channels in the lamina of Drosophila.}, author = {Maximilian Jösch and Schnell, Bettina and Raghu, Shamprasad V and Reiff, Dierk F and Borst, Alexander}, journal = {Nature}, number = {7321}, pages = {300 -- 304}, publisher = {Nature Publishing Group}, title = {{ON and off pathways in Drosophila motion vision}}, doi = {10.1038/nature09545}, volume = {468}, year = {2010}, } @article{1466, abstract = {In Hausel et al. (2008) [10] we presented a conjecture generalizing the Cauchy formula for Macdonald polynomial. This conjecture encodes the mixed Hodge polynomials of the character varieties of representations of the fundamental group of a punctured Riemann surface of genus g. We proved several results which support this conjecture. Here we announce new results which are consequences of those in Hausel et al. (2008) [10].}, author = {Tamas Hausel and Letellier, Emmanuel and Rodríguez Villegas, Fernando}, journal = {Comptes Rendus Mathematique}, number = {3-4}, pages = {131 -- 135}, publisher = {Elsevier}, title = {{Topology of character varieties and representations of quivers}}, doi = {10.1016/j.crma.2010.01.025}, volume = {348}, year = {2010}, } @article{1465, abstract = {We prove a generating function formula for the Betti numbers of Nakajima quiver varieties. We prove that it is a q-deformation of the Weyl-Kac character formula. In particular this implies that the constant term of the polynomial counting the number of absolutely indecomposable representations of a quiver equals the multiplicity of a certain weight in the corresponding Kac-Moody algebra, which was conjectured by Kac in 1982.}, author = {Tamas Hausel}, journal = {Inventiones Mathematicae}, number = {1}, pages = {21 -- 37}, publisher = {Springer}, title = {{Kac's conjecture from Nakajima quiver varieties}}, doi = {10.1007/s00222-010-0241-3}, volume = {181}, year = {2010}, } @inbook{1468, abstract = {This chapter surveys the motivations, related results, and progress made towards the following problem, raised by Hitchin in 1995: What is the space of L2 harmonic forms on the moduli space of Higgs bundles on a Riemann surface?}, author = {Tamas Hausel}, booktitle = {The Many Facets of Geometry: A Tribute to Nigel Hitchin}, publisher = {Oxford University Press}, title = {{S-Duality in HyperkäHler Hodge Theory}}, doi = {10.1093/acprof:oso/9780199534920.003.0016}, year = {2010}, } @article{1722, abstract = {Morphogens are secreted signalling molecules that act in a graded manner to control the pattern of cellular differentiation in developing tissues. An example is Sonic hedgehog (Shh), which acts in several developing vertebrate tissues, including the central nervous system, to provide positional information during embryonic patterning. Here we address how Shh signalling assigns the positional identities of distinct neuronal subtype progenitors throughout the ventral neural tube. Assays of intracellular signal transduction and gene expression indicate that the duration as well as level of signalling is critical for morphogen interpretation. Progenitors of the ventral neuronal subtypes are established sequentially, with progressively more ventral identities requiring correspondingly higher levels and longer periods of Shh signalling. Moreover, cells remain sensitive to changes in Shh signalling for an extended time, reverting to antecedent identities if signalling levels fall below a threshold. Thus, the duration of signalling is important not only for the assignment but also for the refinement and maintenance of positional identity. Together the data suggest a dynamic model for ventral neural tube patterning in which positional information corresponds to the time integral of Shh signalling. This suggests an alternative to conventional models of morphogen action that rely solely on the level of signalling.}, author = {Dessaud, Éric and Ribes, Vanessa and Balaskas, Nikolaos and Yang, Linlin and Pierani, Alessandra and Anna Kicheva and Novitch, Bennett and Briscoe, James and Sasai, Noriaki}, journal = {PLoS Biology}, number = {6}, publisher = {Public Library of Science}, title = {{Dynamic assignment and maintenance of positional identity in the ventral neural tube by the morphogen sonic hedgehog}}, doi = {10.1371/journal.pbio.1000382}, volume = {8}, year = {2010}, } @article{1721, author = {Anna Kicheva and Briscoe, James}, journal = {PLoS Biology}, number = {7}, publisher = {Public Library of Science}, title = {{Limbs made to measure}}, doi = {10.1371/journal.pbio.1000421}, volume = {8}, year = {2010}, } @article{1752, abstract = {The epitaxial growth of germanium on silicon leads to the self-assembly of SiGe nanocrystals by a process that allows the size, composition and position of the nanocrystals to be controlled. This level of control, combined with an inherent compatibility with silicon technology, could prove useful in nanoelectronic applications. Here, we report the confinement of holes in quantum-dot devices made by directly contacting individual SiGe nanocrystals with aluminium electrodes, and the production of hybrid superconductor- semiconductor devices, such as resonant supercurrent transistors, when the quantum dot is strongly coupled to the electrodes. Charge transport measurements on weakly coupled quantum dots reveal discrete energy spectra, with the confined hole states displaying anisotropic gyromagnetic factors and strong spin-orbit coupling with pronounced dependences on gate voltage and magnetic field.}, author = {Georgios Katsaros and Spathis, Panayotis N and Stoffel, Mathieu and Fournel, Frank and Mongillo, Massimo and Bouchiat, Vincent and Lefloch, François and Rastelli, Armando and Schmidt, Oliver G and De Franceschi, Silvano}, journal = {Nature Nanotechnology}, number = {6}, pages = {458 -- 464}, publisher = {Nature Publishing Group}, title = {{Hybrid superconductor-semiconductor devices made from self-assembled SiGe nanocrystals on silicon}}, doi = {10.1038/nnano.2010.84}, volume = {5}, year = {2010}, } @article{1753, abstract = {We investigate electronic transport in n-i-n GaN nanowires with and without AlN double barriers. The nanowires are grown by catalyst-free, plasma-assisted molecular beam epitaxy enabling abrupt GaN/AlN interfaces as well as longitudinal n-type doping modulation. At low temperature, transport in n-i-n GaN nanowires is dominated by the Coulomb blockade effect. Carriers are confined in the undoped middle region, forming single or multiple islands with a characteristic length of ∼100 nm. The incorporation of two AlN tunnel barriers causes confinement to occur within the GaN dot in between. In the case of a 6 nm thick dot and 2 nm thick barriers, we observe characteristic signatures of Coulomb-blockaded transport in single quantum dots with discrete energy states. For thinner dots and barriers, Coulomb-blockade effects do not play a significant role while the onset of resonant tunneling via the confined quantum levels is accompanied by a negative differential resistance surviving up to ∼150 K.}, author = {Songmuang, Rudeeson and Georgios Katsaros and Monroy, Eva and Spathis, Panayotis N and Bougerol, Catherine and Mongillo, Massimo and De Franceschi, Silvano}, journal = {Nano Letters}, number = {9}, pages = {3545 -- 3550}, publisher = {American Chemical Society}, title = {{Quantum transport in GaN/AlN double-barrier heterostructure nanowires}}, doi = {10.1021/nl1017578}, volume = {10}, year = {2010}, } @article{1773, abstract = {The quantum properties of electromagnetic, mechanical or other harmonic oscillators can be revealed by investigating their strong coherent coupling to a single quantum two level system in an approach known as cavity quantum electrodynamics (QED). At temperatures much lower than the characteristic energy level spacing the observation of vacuum Rabi oscillations or mode splittings with one or a few quanta asserts the quantum nature of the oscillator. Here, we study how the classical response of a cavity QED system emerges from the quantum one when its thermal occupation-or effective temperature-is raised gradually over 5 orders of magnitude. In this way we explore in detail the continuous quantum-to-classical crossover and demonstrate how to extract effective cavity field temperatures from both spectroscopic and time-resolved vacuum Rabi measurements.}, author = {Johannes Fink and Steffen, L. Kraig and Studer, Peter and Bishop, Lev S and Baur, Matthias P and Bianchetti, R and Bozyigit, Deniz and Lang, C and Filipp, Stefan and Leek, Peter J and Wallraff, Andreas}, journal = {Physical Review Letters}, number = {16}, publisher = {American Physical Society}, title = {{Quantum-to-classical transition in cavity quantum electrodynamics}}, doi = {10.1103/PhysRevLett.105.163601}, volume = {105}, year = {2010}, } @article{1774, abstract = {A number of superconducting qubits, such as the transmon or the phase qubit, have an energy level structure with small anharmonicity. This allows for convenient access of higher excited states with similar frequencies. However, special care has to be taken to avoid unwanted higher-level populations when using short control pulses. Here we demonstrate the preparation of arbitrary three level superposition states using optimal control techniques in a transmon. Performing dispersive readout, we extract the populations of all three levels of the qutrit and study the coherence of its excited states. Finally we demonstrate full quantum state tomography of the prepared qutrit states and evaluate the fidelities of a set of states, finding on average 95%.}, author = {Bianchetti, R and Filipp, Stefan and Baur, Matthias P and Johannes Fink and Lang, C and Steffen, L. Kraig and Boissonneault, Maxime and Blais, Alexandre and Wallraff, Andreas}, journal = {Physical Review Letters}, number = {22}, publisher = {American Physical Society}, title = {{Control and tomography of a three level superconducting artificial atom}}, doi = {10.1103/PhysRevLett.105.223601}, volume = {105}, year = {2010}, } @article{1772, abstract = {We present the realization of a cavity quantum electrodynamics setup in which photons of strongly different lifetimes are engineered in different harmonic modes of the same cavity. We achieve this in a superconducting transmission line resonator with superconducting qubits coupled to the different modes. One cavity mode is strongly coupled to a detection line for qubit state readout, while a second long lifetime mode is used for photon storage and coherent quantum operations. We demonstrate sideband-based measurement of photon coherence, generation of n photon Fock states and the scaling of the sideband Rabi frequency with √n using a scheme that may be extended to realize sideband-based two-qubit logic gates.}, author = {Leek, Peter J and Baur, Matthias P and Johannes Fink and Bianchetti, R and Steffen, L. Kraig and Filipp, Stefan and Wallraff, Andreas}, journal = {Physical Review Letters}, number = {10}, publisher = {American Physical Society}, title = {{Cavity quantum electrodynamics with separate photon storage and qubit readout modes}}, doi = {10.1103/PhysRevLett.104.100504}, volume = {104}, year = {2010}, } @article{1800, abstract = {Retinitis pigmentosa refers to a diverse group of hereditary diseases that lead to incurable blindness, affecting two million people worldwide. As a common pathology, rod photoreceptors die early, whereas light-insensitive, morphologically altered cone photoreceptors persist longer. It is unknown if these cones are accessible for therapeutic intervention. Here, we show that expression of archaebacterial halorhodopsin in light-insensitive cones can substitute for the native phototransduction cascade and restore light sensitivity in mouse models of retinitis pigmentosa. Resensitized photoreceptors activate all retinal cone pathways, drive sophisticated retinal circuit functions (including directional selectivity), activate cortical circuits, and mediate visually guided behaviors. Using human ex vivo retinas, we show that halorhodopsin can reactivate light-insensitive human photoreceptors. Finally, we identified blind patients with persisting, light-insensitive cones for potential halorhodopsin-based therapy.}, author = {Busskamp, Volker and Duebel, Jens and Bálya, Dávid and Fradot, Mathias and Viney, Tim J and Sandra Siegert and Groner, Anna C and Cabuy, Erik and Forster, Valérie and Seeliger, Mathias W and Biel, Martin and Humphries, Peter and Pâques, Michel and Mohand-Saïd, Saddek and Trono, Didier and Deisseroth, Karl A and Sähel, José A and Picaud, Serge A and Roska, Botond M}, journal = {Science}, number = {5990}, pages = {413 -- 417}, publisher = {American Association for the Advancement of Science}, title = {{Genetic reactivation of cone photoreceptors restores visual responses in retinitis pigmentosa}}, doi = {10.1126/science.1190897}, volume = {329}, year = {2010}, } @article{1970, abstract = {Complex I is the first enzyme of the respiratory chain and has a central role in cellular energy production, coupling electron transfer between NADH and quinone to proton translocation by an unknown mechanism. Dysfunction of complex I has been implicated in many human neurodegenerative diseases. We have determined the structure of its hydrophilic domain previously. Here, we report the α-helical structure of the membrane domain of complex I from Escherichia coli at 3.9 Å resolution. The antiporter-like subunits NuoL/M/N each contain 14 conserved transmembrane (TM) helices. Two of them are discontinuous, as in some transporters. Unexpectedly, subunit NuoL also contains a 110-Å long amphipathic α-helix, spanning almost the entire length of the domain. Furthermore, we have determined the structure of the entire complex I from Thermus thermophilus at 4.5 Å resolution. The L-shaped assembly consists of the α-helical model for the membrane domain, with 63 TM helices, and the known structure of the hydrophilic domain. The architecture of the complex provides strong clues about the coupling mechanism: the conformational changes at the interface of the two main domains may drive the long amphipathic α-helix of NuoL in a piston-like motion, tilting nearby discontinuous TM helices, resulting in proton translocation.}, author = {Efremov, Rouslan G and Baradaran, Rozbeh and Leonid Sazanov}, journal = {Nature}, number = {7297}, pages = {441 -- 445}, publisher = {Nature Publishing Group}, title = {{The architecture of respiratory complex I}}, doi = {10.1038/nature09066}, volume = {465}, year = {2010}, } @phdthesis{2075, abstract = {This thesis investigates the combination of data-driven and physically based techniques for acquiring, modeling, and animating deformable materials, with a special focus on human faces. Furthermore, based on these techniques, we introduce a data-driven process for designing and fabricating materials with desired deformation behavior. Realistic simulation behavior, surface details, and appearance are still demanding tasks. Neither pure data-driven, pure procedural, nor pure physical methods are best suited for accurate synthesis of facial motion and details (both for appearance and geometry), due to the difficulties in model design, parameter estimation, and desired controllability for animators. Capturing of a small but representative amount of real data, and then synthesizing diverse on-demand examples with physically-based models and real data as input benefits from both sides: Highly realistic model behavior due to real-world data and controllability due to physically-based models. To model the face and its behavior, hybrid physically-based and data-driven approaches are elaborated. We investigate surface-based representations as well as a solid representation based on FEM. To achieve realistic behavior, we propose to build light-weighted data capture devices to acquire real-world data to estimate model parameters and to employ concepts from data-driven modeling techniques and machine learning. The resulting models support simple acquisition systems, offer techniques to process and extract model parameters from real-world data, provide a compact representation of the facial geometry and its motion, and allow intuitive editing. We demonstrate applications such as capture of facial geometry and motion and real-time animation and transfer of facial details, and show that our soft tissue model can react to external forces and produce realistic deformations beyond facial expressions. Based on this model, we furthermore introduce a data-driven process for designing and fabricating materials with desired deformation behavior. The process starts with measuring deformation properties of base materials. Each material is represented as a non-linear stress-strain relationship in a finite-element model. For material design and fabrication, we introduce an optimization process that finds the best combination of base materials that meets a user’s criteria specified by example deformations. Our algorithm employs a number of strategies to prune poor solutions from the combinatorial search space. We finally demonstrate the complete process by designing and fabricating objects with complex heterogeneous materials using modern multi-material 3D printers. }, author = {Bernd Bickel}, booktitle = {Unknown}, number = {7458}, publisher = {Unknown}, title = {{Measurement-based modeling and fabrication of deformable materials for human faces}}, doi = {dx.doi.org/10.3929/ethz-a-006354908}, volume = {499}, year = {2010}, } @article{2071, abstract = {The X or Z chromosome has several characteristics that distinguish it from the autosomes, namely hemizygosity in the heterogametic sex, and a potentially different effective population size, both of which may influence the rate and nature of evolution. In particular, there may be an accelerated rate of adaptive change for X-linked compared to autosomal coding sequences, often referred to as the Faster-X effect. Empirical studies have indicated that the strength of Faster-X evolution varies among different species, and theoretical treatments have shown that demography and mating system can substantially affect the degree of Faster-X evolution. Here we integrate genomic data on Faster-X evolution from a variety of animals with the demographic factors, mating system, and sex chromosome regulatory characteristics that may influence it. Our results suggest that differences in effective population size and mechanisms of dosage compensation may influence the perceived extent of Faster-X evolution, and help to explain several clade-specific patterns that we observe.}, author = {Mank, Judith E and Beatriz Vicoso and Berlin, Sofia and Charlesworth, Brian}, journal = {Evolution}, number = {3}, pages = {663 -- 674}, publisher = {Wiley-Blackwell}, title = {{Effective population size and the Faster-X effect: Empirical results and their interpretation}}, doi = {10.1111/j.1558-5646.2009.00853.x}, volume = {64}, year = {2010}, } @article{2095, abstract = {This paper describes a passive stereo system for capturing the 3D geometry of a face in a single-shot under standard light sources. The system is low-cost and easy to deploy. Results are submillimeter accurate and commensurate with those from state-ofthe-art systems based on active lighting, and the models meet the quality requirements of a demanding domain like the movie industry. Recovered models are shown for captures from both high-end cameras in a studio setting and from a consumer binocular-stereo camera, demonstrating scalability across a spectrum of camera deployments, and showing the potential for 3D face modeling to move beyond the professional arena and into the emerging consumer market in stereoscopic photography. Our primary technical contribution is a modification of standard stereo refinement methods to capture pore-scale geometry, using a qualitative approach that produces visually realistic results. The second technical contribution is a calibration method suited to face capture systems. The systemic contribution includes multiple demonstrations of system robustness and quality. These include capture in a studio setup, capture off a consumer binocular-stereo camera, scanning of faces of varying gender and ethnicity and age, capture of highly-transient facial expression, and scanning a physical mask to provide ground-truth validation.}, author = {Beeler, Thabo and Bernd Bickel and Beardsley, Paul A and Sumner, Bob and Groß, Markus S}, journal = {ACM Transactions on Graphics}, number = {4}, publisher = {ACM}, title = {{High-quality single-shot capture of facial geometry}}, doi = {10.1145/1778765.1778777}, volume = {29}, year = {2010}, } @article{2097, abstract = {This paper introduces a data-driven process for designing and fabricating materials with desired deformation behavior. Our process starts with measuring deformation properties of base materials. For each base material we acquire a set of example deformations, and we represent the material as a non-linear stress-strain relationship in a finite-element model. We have validated our material measurement process by comparing simulations of arbitrary stacks of base materials with measured deformations of fabricated material stacks. After material measurement, our process continues with designing stacked layers of base materials. We introduce an optimization process that finds the best combination of stacked layers that meets a user's criteria specified by example deformations. Our algorithm employs a number of strategies to prune poor solutions from the combinatorial search space. We demonstrate the complete process by designing and fabricating objects with complex heterogeneous materials using modern multi-material 3D printers.}, author = {Bernd Bickel and Bac̈her, Moritz and Otaduy, Miguel A and Lee, Hyunho R and Pfister, Hanspeter and Groß, Markus S and Matusik, Wojciech}, journal = {ACM Transactions on Graphics}, number = {4}, publisher = {ACM}, title = {{Design and fabrication of materials with desired deformation behavior}}, doi = {10.1145/1778765.1778800}, volume = {29}, year = {2010}, } @article{2096, abstract = {Point-based graphics has gained much attention as an alternative to polygon-based approaches because of its simplicity and flexibility. However, current point-based techniques do not provide a sufficient rendering quality for translucent materials such as human skin. In this paper, we propose a point-based framework with subsurface scattering of light, which is important to create the soft and semi-translucent appearance of human skin. To accurately simulate subsurface scattering in multilayered materials, we present splat-based diffusion to apply a linear combination of several Gaussian basis functions to each splat in object space. Compared to existing point-based approaches, our method offers a significantly improved visual quality in rendering human faces and provides a similar visual quality to polygon-based rendering using the texture space diffusion technique. We demonstrate the effectiveness of our approach in rendering scanned faces realistically.}, author = {Kim, Hyeonjoong and Bernd Bickel and Groß, Markus S and Choi, Soomi}, journal = {Science in China, Series F: Information Sciences}, number = {5}, pages = {911 -- 919}, publisher = {Springer}, title = {{Subsurface scattering using splat-based diffusion in point-based rendering}}, doi = {10.1007/s11432-010-0068-y}, volume = {53}, year = {2010}, } @article{2124, abstract = {We develop a theory of Malliavin calculus for Banach space-valued random variables. Using radonifying operators instead of symmetric tensor products we extend the Wiener-Itô isometry to Banach spaces. In the white noise case we obtain two sided Lp-estimates for multiple stochastic integrals in arbitrary Banach spaces. It is shown that the Malliavin derivative is bounded on vector-valued Wiener-Itô chaoses. Our main tools are decoupling inequalities for vector-valued random variables. In the opposite direction we use Meyer's inequalities to give a new proof of a decoupling result for Gaussian chaoses in UMD Banach spaces.}, author = {Jan Maas}, journal = {Journal of Mathematical Analysis and Applications}, number = {2}, pages = {383 -- 398}, publisher = {Academic Press}, title = {{Malliavin calculus and decoupling inequalities in Banach spaces}}, doi = {10.1016/j.jmaa.2009.08.041}, volume = {363}, year = {2010}, } @article{2194, abstract = {We develop an analytic model of vector correlations in rotationally inelastic atom-diatom collisions and test it against the much examined Ar-NO (X2Π) system. Based on the Fraunhofer scattering of matter waves, the model furnishes complex scattering amplitudes needed to evaluate the polarization moments characterizing the quantum stereodynamics. The analytic polarization moments are found to be in an excellent agreement with experimental results and with close-coupling calculations available at thermal energies. The model reveals that the stereodynamics is governed by diffraction from the repulsive core of the Ar-NO potential, which can be characterized by a single Legendre moment.}, author = {Mikhail Lemeshko and Friedrich, Břetislav}, journal = {Physical Chemistry Chemical Physics}, number = {5}, pages = {1038 -- 1041}, publisher = {Royal Society of Chemistry}, title = {{An analytic model of the stereodynamics of rotationally inelastic molecular collisions}}, doi = {10.1039/B920899B }, volume = {12}, year = {2010}, } @article{2196, abstract = {We evaluate the shifts imparted to vibrational and rotational levels of a linear molecule by a nonresonant laser field at intensities of up to 10 12 W/cm2. Both types of shift are found to be either positive or negative, depending on the initial rotational state acted upon by the field. An adiabatic field-molecule interaction imparts a rotational energy shift which is negative and exceeds the concomitant positive vibrational shift by a few orders of magnitude. The rovibrational states are thus pushed downward in such a field. A nonresonant pulsed laser field that interacts nonadiabatically with the molecule is found to impart rotational and vibrational shifts of the same order of magnitude. The nonadiabatic energy transfer occurs most readily at a pulse duration which amounts to about a tenth of the molecule's rotational period and vanishes when the sudden regime is attained for shorter pulses. We applied our treatment to the much-studied 87Rb2 molecule in the last bound vibrational levels of its lowest singlet and triplet electronic states. Our calculations indicate that 15 and 1.5 ns laser pulses of an intensity in excess of 5 × 109 W/cm2 are capable of dissociating the molecule due to the vibrational shift. Lesser shifts can be used to fine-tune the rovibrational levels and thereby affect collisional resonances by the nonresonant light. The energy shifts due to laser intensities of 109 W/cm2 may be discernible spectroscopically, with a 10 MHz resolution.}, author = {Mikhail Lemeshko and Friedrich, Břetislav}, journal = {Journal of Physical Chemistry A}, number = {36}, pages = {9848 -- 9854}, publisher = {American Chemical Society}, title = {{Fine-tuning molecular energy levels by nonresonant laser pulses}}, doi = {10.1021/jp1032299}, volume = {114}, year = {2010}, } @article{2195, abstract = {Following upon our recent work on vector correlations in the Ar-NO collisions [Lemeshko and Friedrich, Phys. Chem. Chem. Phys. 12, 1038 (2010)], we compare model results with close-coupling calculations for a range of channels and collision energies for the He-NO system. The striking agreement between the model and exact polarization moments indicates that the stereodynamics of rotationally inelastic atom-molecule collisions at thermal energies is governed by diffraction of matter waves from a two-dimensional repulsive core of the atom-molecule potential. Furthermore, the model polarization moments characterizing the He-NO, He- O2, He-OH, and He-CaH stereodynamics are found to coalesce into a single, distinctive pattern, which can serve as a "fingerprint" to identify diffraction-driven stereodynamics in future work. }, author = {Mikhail Lemeshko and Jambrina, Pablo G and De Miranda, Marcelo P and Friedrich, Břetislav}, journal = {Journal of Chemical Physics}, number = {16}, publisher = {American Institute of Physics}, title = {{Communications: When diffraction rules the stereodynamics of rotationally inelastic collisions}}, doi = {10.1063/1.3386530}, volume = {132}, year = {2010}, } @article{2197, abstract = {We present an analytic model of the refractive index for matter waves propagating through atomic or molecular gases. The model, which combines the Wentzel-Kramers-Brillouin (WKB) treatment of the long-range attraction with the Fraunhofer model treatment of the short-range repulsion, furnishes a refractive index in compelling agreement with recent experiments of Jacquey [Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.98.240405 98, 240405 (2007)] on Li atom matter waves passing through dilute noble gases. We show that the diffractive contribution, which arises from scattering by a two-dimensional "hard core" of the potential, is essential for obtaining a correct imaginary part of the refractive index.}, author = {Mikhail Lemeshko and Friedrich, Břetislav}, journal = {Physical Review A - Atomic, Molecular, and Optical Physics}, number = {2}, publisher = {American Physical Society}, title = {{Multiple scattering of matter waves: An analytic model of the refractive index for atomic and molecular gases}}, doi = {10.1103/PhysRevA.82.022711}, volume = {82}, year = {2010}, } @inbook{2309, abstract = {The importance of chloride ions in cell physiology has not been fully recognized until recently, in spite of the fact that chloride (Cl-), together with bicarbonate, is the most abundant free anion in animal cells, and performs or determines fundamental biological functions in all tissues. For many years it was thought that Cl- was distributed in thermodynamic equilibrium across the plasma membrane of most cells. Research carried out during the last couple of decades has led to a dramatic change in this simplistic view. We now know that most animal cells, neurons included, exhibit a non-equilibrium distribution of Cl- across their plasma membranes. Over the last 10 to 15 years, with the growth of molecular biology and the advent of new optical methods, an enormous amount of exciting new information has become available on the molecular structure and function of Cl- channels and carriers. In nerve cells, Cl- channels and carriers play key functional roles in GABA- and glycine-mediated synaptic inhibition, neuronal growth and development, extracellular potassium scavenging, sensory-transduction, neurotransmitter uptake and cell volume control. Disruption of Cl- homeostasis in neurons underlies pathological conditions such as epilepsy, deafness, imbalance, brain edema and ischemia, pain and neurogenic inflammation. This book is about how chloride ions are regulated and how they cross the plasma membrane of neurons. It spans from molecular structure and function of carriers and channels involved in Cl- transport to their role in various diseases. * The first comprehensive book on the structure, molecular biology, cell physiology, and role in diseases of chloride transporters / channels in the nervous system in almost 20 years * Chloride is the most abundant free anion in animal cells. THis book summarizes and integrates for the first time the important research of the past two decades that has shown that Cl- channels and carriers play key functional roles in GABA- and glycine-mediated synaptic inhibition, neuronal growth and development, extracellular potassium scavenging, sensory-transduction, neurotransmitter uptake and cell volume control. * The first book that systematically discusses the result of disruption of Cl- homeostasis in neurons which underlies pathological conditions such as epilepsy, deafness, imbalance, brain edema and ischemia, pain and neurogenic inflammation. * Spanning topics from molecular structure and function of carriers and channels involved in Cl- transport to their role in various diseases. * Involves all of the leading researchers in the field. * INcludes an extensive introductory section that covers basic thermodynamic and kinetics aspects of Cl- transport, as well as current methods for studying Cl- regulation, spanning from fluorescent dyes in single cells to knock-out models to make the book available for a growing population of graduate students and postdocs entering the field.}, author = {Stauber, Tobias and Gaia Novarino and Jentsch, Thomas J}, booktitle = {Physiology and Pathology of chloride transporters and channels in the nervous system}, pages = {209 -- 231}, publisher = {Elsevier}, title = {{The CLC family of chloride channels and transporters}}, doi = {10.1016/B978-0-12-374373-2.00012-1}, year = {2010}, } @article{2311, abstract = {Inactivation of the mainly endosomal 2Cl-/H+- exchanger ClC-5 severely impairs endocytosis in renal proximal tubules and underlies the human kidney stone disorder Dent's disease. In heterologous expression systems, interaction of the E3 ubiquitin ligasesWWP2and Nedd4-2 with a "PY-motif" in the cytoplasmic C terminus of ClC-5 stimulates its internalization from the plasma membrane and may influence receptor-mediated endocytosis. We asked whether this interaction is relevant in vivo and generated mice in which the PY-motif was destroyed by a point mutation. Unlike ClC-5 knock-out mice, these knock-in mice displayed neither low molecular weight proteinuria nor hyperphosphaturia, and both receptor-mediated and fluid-phase endocytosis were normal. The abundances and localizations of the endocytic receptor megalin and of the Na+-coupled phosphate transporter NaPi-2a (Npt2) were not changed, either. To explore whether the discrepancy in results from heterologous expression studies might be due to heteromerization of ClC-5 with ClC-3 or ClC-4 in vivo, we studied knock-in mice additionally deleted for those related transporters. Disruption of neither ClC-3 nor ClC-4 led to proteinuria or impaired proximal tubular endocytosis by itself, nor in combination with the PY-mutant of ClC-5. Endocytosis of cells lacking ClC-5 was not impaired further when ClC-3 or ClC-4 was additionally deleted. We conclude that ClC-5 is unique among CLC proteins in being crucial for proximal tubular endocytosis and that PY-motif-dependent ubiquitylation of ClC-5 is dispensable for this role.}, author = {Rickheit, Gesa and Wartosch, Lena and Schaffer, Sven and Stobrawa, Sandra M and Gaia Novarino and Weinert, Stefanie and Jentsch, Thomas J}, journal = {Journal of Biological Chemistry}, number = {23}, pages = {17595 -- 17603}, publisher = {American Society for Biochemistry and Molecular Biology}, title = {{Role of ClC-5 in renal endocytosis is unique among ClC exchangers and does not require PY-motif-dependent ubiquitylation}}, doi = {10.1074/jbc.M110.115600}, volume = {285}, year = {2010}, } @article{2310, abstract = {Loss of the endosomal anion transport protein ClC-5 impairs renal endocytosis and underlies human Dent's disease. ClC-5 is thought to promote endocytosis by facilitating endosomal acidification through the neutralization of proton pump currents. However, ClC-5 is a 2 chloride (Cl-)/proton (H+) exchanger rather than a Cl- channel. We generated mice that carry the uncoupling E211A (unc) mutation that converts CLC-5 into a pure CL- conductor. Adenosine triphosphate (ATP)-dependent acidification of renal endosomes was reduced in mice in which ClC-5 was knocked out, but normal in Clcn5unc mice. However, their proximal tubular endocytosis was also impaired. Thus, endosomal chloride concentration, which is raised by CLC-5 in exchange for protons accumulated by the H+-ATPase, may play a role in endocytosis.}, author = {Gaia Novarino and Weinert, Stefanie and Rickheit, Gesa and Jentsch, Thomas J}, journal = {Science}, number = {5984}, pages = {1398 -- 1401}, publisher = {American Association for the Advancement of Science}, title = {{Endosomal chloride-proton exchange rather than chloride conductance is crucial for renal endocytosis}}, doi = {10.1126/science.1188070}, volume = {328}, year = {2010}, } @article{231, abstract = {Let X be a projective cubic hypersurface of dimension 11 or more, which is defined over ℚ. We show that X(ℚ) is non-empty provided that the cubic form defining X can be written as the sum of two forms that share no common variables.}, author = {Timothy Browning and Colliot-Thélène, Jean-Louis}, journal = {Compositio Mathematica}, number = {4}, pages = {853 -- 885}, publisher = {Cambridge University Press}, title = {{Rational points on cubic hypersurfaces that split off a form. With an appendix by J-L Colliot-Thélène}}, doi = {10.1112/S0010437X0900459X}, volume = {146}, year = {2010}, } @article{232, abstract = {We study the average order of the divisor function, as it ranges over the values of binary quartic forms that are reducible over ℚ.}, author = {De La Bretèche, Régis and Browning, Timothy D}, journal = {Journal fur die Reine und Angewandte Mathematik}, number = {646}, pages = {1 -- 44}, publisher = {Walter de Gruyter}, title = {{Le problème des diviseurs pour des formes binaires de degré 4}}, doi = {10.1515/CRELLE.2010.064}, year = {2010}, } @inproceedings{2322, author = {Frank, Rupert L and Lieb, Élliott H and Robert Seiringer}, pages = {523 -- 535}, publisher = {World Scientific Publishing}, title = {{ Equivalence of Sobolev inequalities and Lieb-Thirring inequalities}}, doi = {10.1142/9789814304634_0045 }, year = {2010}, } @inproceedings{2323, abstract = {Since the first experimental realization of Bose-Einstein condensation in cold atomic gases in 1995 there has been a surge of activity in this field. Ingenious experiments have allowed us to probe matter close to zero temperature and reveal some of the fascinating effects quantum mechanics has bestowed on nature. It is a challenge for mathematical physicists to understand these various phenomena from first principles, that is, starting from the underlying many-body Schrödinger equation. Recent progress in this direction concerns mainly equilibrium properties of dilute, cold quantum gases. We shall explain some of the results in this article, and describe the mathematics involved in understanding these phenomena. Topics include the ground state energy and the free energy at positive temperature, the effect of interparticle interaction on the critical temperature for Bose-Einstein condensation, as well as the occurrence of superfluidity and quantized vortices in rapidly rotating gases.}, author = {Robert Seiringer}, pages = {231 -- 245}, publisher = {World Scientific Publishing}, title = {{Hot topics on cold gases}}, doi = {10.1142/9789814304634_0013}, year = {2010}, } @inbook{2324, abstract = {We determine the sharp constant in the Hardy inequality for fractional Sobolev spaces on half-spaces. Our proof relies on a nonlinear and nonlocal version of the ground state representation.}, author = {Frank, Rupert L and Robert Seiringer}, booktitle = {Around the Research of Vladimir Maz'ya I}, pages = {161 -- 167}, publisher = {Springer}, title = {{Sharp fractional Hardy inequalities in half-spaces}}, doi = {10.1007/978-1-4419-1341-8_6}, volume = {11}, year = {2010}, } @article{2392, abstract = {The binding of polarons, or its absence, is an old and subtle topic. Here we prove two things rigorously. First, the transition from many-body collapse to the existence of a thermodynamic limit for N polarons occurs precisely at U=2α, where U is the electronic Coulomb repulsion and α is the polaron coupling constant. Second, if U is large enough, there is no multipolaron binding of any kind. Considering the known fact that there is binding for some U>2α, these conclusions are not obvious and their proof has been an open problem for some time.}, author = {Frank, Rupert L and Lieb, Élliott H and Robert Seiringer and Thomas, Lawrence E}, journal = {Physical Review Letters}, number = {21}, publisher = {American Physical Society}, title = {{Bipolaron and N-polaron binding energies}}, doi = {10.1103/PhysRevLett.104.210402}, volume = {104}, year = {2010}, } @article{2389, abstract = {We study the eigenvalues of Schrödinger type operators T + λV and their asymptotic behavior in the small coupling limit λ → 0, in the case where the symbol of the kinetic energy, T (p), strongly degenerates on a non-trivial manifold of codimension one.}, author = {Hainzl, Christian and Robert Seiringer}, journal = {Mathematische Nachrichten}, number = {3}, pages = {489 -- 499}, publisher = {Wiley-Blackwell}, title = {{Asymptotic behavior of eigenvalues of Schrödinger type operators with degenerate kinetic energy}}, doi = {10.1002/mana.200810195}, volume = {283}, year = {2010}, } @article{2409, abstract = {Background: The availability of many gene alignments with overlapping taxon sets raises the question of which strategy is the best to infer species phylogenies from multiple gene information. Methods and programs abound that use the gene alignment in different ways to reconstruct the species tree. In particular, different methods combine the original data at different points along the way from the underlying sequences to the final tree. Accordingly, they are classified into superalignment, supertree and medium-level approaches. Here, we present a simulation study to compare different methods from each of these three approaches. Results: We observe that superalignment methods usually outperform the other approaches over a wide range of parameters including sparse data and gene-specific evolutionary parameters. In the presence of high incongruency among gene trees, however, other combination methods show better performance than the superalignment approach. Surprisingly, some supertree and medium-level methods exhibit, on average, worse results than a single gene phylogeny with complete taxon information. Conclusions: For some methods, using the reconstructed gene tree as an estimation of the species tree is superior to the combination of incomplete information. Superalignment usually performs best since it is less susceptible to stochastic error. Supertree methods can outperform superalignment in the presence of gene-tree conflict.}, author = {Kupczok, Anne and Schmidt, Heiko and Von Haeseler, Arndt}, journal = {Algorithms for Molecular Biology}, number = {1}, publisher = {BioMed Central}, title = {{Accuracy of phylogeny reconstruction methods combining overlapping gene data sets }}, doi = {10.1186/1748-7188-5-37}, volume = {5}, year = {2010}, } @article{2435, abstract = {We consider a generalization of the van Kampen-Flores Theorem and relate it to the long-standing g-conjecture for simplicial spheres. }, author = {Nevo, Eran and Uli Wagner}, journal = {Israel Journal of Mathematics}, number = {1}, pages = {381 -- 402}, publisher = {Springer}, title = {{On the embeddability of skeleta of spheres}}, doi = {10.1007/s11856-009-0119-5}, volume = {174}, year = {2010}, } @article{2442, abstract = {In a new study published in this issue of Developmental Cell, Krouk et al. reveal a surprising mechanism by which plant root systems adapt their architecture for soil exploitation. The dual transporter NRT1.1 uses both nitrate and the plant hormone auxin as substrates, enabling soil nitrate availability to regulate auxin-driven lateral root development.}, author = {Beeckman, Tom and Friml, Jirí}, journal = {Developmental Cell}, number = {6}, pages = {877 -- 878}, publisher = {Cell Press}, title = {{Nitrate Contra Auxin: Nutrient Sensing by roots}}, doi = {10.1016/j.devcel.2010.05.020}, volume = {18}, year = {2010}, } @article{2503, abstract = {Epilepsy is a devastating and poorly understood disease. Mutations in a secreted neuronal protein, leucine-rich glioma inactivated 1 (LGI1), were reported in patients with an inherited form of human epilepsy, autosomal dominant partial epilepsy with auditory features (ADPEAF). Here, we report an essential role of LGI1 as an antiepileptogenic ligand. We find that loss of LGI1 in mice (LGI1-/-) causes lethal epilepsy, which is specifically rescued by the neuronal expression of LGI1 transgene, but not LGI3. Moreover, heterozygous mice for the LGI1 mutation (LGI1+/-) show lowered seizure thresholds. Extracellularly secreted LGI1 links two epilepsy-related receptors, ADAM22 and ADAM23, in the brain and organizes a transsynaptic protein complex that includes presynaptic potassium channels and postsynaptic AMPA receptor scaffolds. A lack of LGI1 disrupts this synaptic protein connection and selectively reduces AMPA receptor-mediated synaptic transmission in the hippocampus. Thus, LGI1 may serve as a major determinant of brain excitation, and the LGI1 gene-targeted mouse provides a good model for human epilepsy.}, author = {Fukata, Yuko and Lovero, Kathryn L and Iwanaga, Tsuyoshi and Watanabe, Atsushi and Yokoi, Norihiko and Tabuchi, Katsuhiko and Ryuichi Shigemoto and Nicoll, Roger A and Fukata, Masaki}, journal = {PNAS}, number = {8}, pages = {3799 -- 3804}, publisher = {National Academy of Sciences}, title = {{Disruption of LGI1-linked synaptic complex causes abnormal synaptic transmission and epilepsy}}, doi = {10.1073/pnas.0914537107}, volume = {107}, year = {2010}, } @article{2508, abstract = {The activity patterns of subthalamic nucleus (STN) neurons are intimately linked to motor function and dysfunction and arise through the complex interaction of intrinsic properties and inhibitory and excitatory synaptic inputs. In many neurons, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels play key roles in intrinsic excitability and synaptic integration both under normal conditions and in disease states. However, in STN neurons, which strongly express HCN channels, their roles remain relatively obscure. To address this deficit, complementary molecular and cellular electrophysiological, imaging, and computational approaches were applied to the rat STN. Molecular profiling demonstrated that individual STN neurons express mRNA encoding several HCN subunits, with HCN2 and 3 being the most abundant. Light and electron microscopic analysis showed that HCN2 subunits are strongly expressed and distributed throughout the somatodendritic plasma membrane. Voltage-, current-, and dynamic-clamp analysis, two-photon Ca 2+ imaging, and computational modeling revealed that HCN channels are activated by GABA A receptor-mediated inputs and thus limit synaptic hyperpolarization and deinactivation of low-voltage-activated Ca 2+ channels. Although HCN channels also limited the temporal summation of EPSPs, generated through two-photon uncaging of glutamate, this action was largely shunted by GABAergic inhibition that was necessary for HCN channel activation. Together the data demonstrate that HCN channels in STN neurons selectively counteract GABA A receptor-mediated inhibition arising from the globus pallidus and thus promote single-spike activity rather than rebound burst firing. }, author = {Atherton, Jeremy F and Kitano, Katsunori and Baufreton, Jérôme and Fan, Kai and Wokosin, David L and Tkatch, Tatiana and Ryuichi Shigemoto and Surmeier, James D and Bevan, Mark D}, journal = {Journal of Neuroscience}, number = {47}, pages = {16025 -- 16040}, publisher = {Society for Neuroscience}, title = {{Selective participation of somatodendritic HCN channels in inhibitory but not excitatory synaptic integration in neurons of the subthalamic nucleus}}, doi = {10.1523/JNEUROSCI.3898-10.2010}, volume = {30}, year = {2010}, } @article{2509, abstract = {Hippocampal CA1 pyramidal cells, which receive γ-aminobutyric acid (GABA)ergic input from at least 18 types of presynaptic neuron, express 14 subunits of the pentameric GABAA receptor. The relative contribution of any subunit to synaptic and extrasynaptic receptors influences the dynamics of GABA and drug actions. Synaptic receptors mediate phasic GABA-evoked conductance and extrasynaptic receptors contribute to a tonic conductance. We used freeze-fracture replica-immunogold labelling, a sensitive quantitative immunocytochemical method, to detect synaptic and extrasynaptic pools of the alpha1, alpha2 and beta3 subunits. Antibodies to the cytoplasmic loop of the subunits showed immunogold particles concentrated on distinct clusters of intramembrane particles (IMPs) on the cytoplasmic face of the plasma membrane on the somata, dendrites and axon initial segments, with an abrupt decrease in labelling at the edge of the IMP cluster. Neuroligin-2, a GABAergic synapse-specific adhesion molecule, co-labels all beta3 subunit-rich IMP clusters, therefore we considered them synapses. Double-labelling for two subunits showed that virtually all somatic synapses contain the alpha1, alpha2 and beta3 subunits. The extrasynaptic plasma membrane of the somata, dendrites and dendritic spines showed low-density immunolabelling. Synaptic labelling densities on somata for the alpha1, alpha2 and beta3 subunits were 78-132, 94 and 79 times higher than on the extrasynaptic membranes, respectively. As GABAergic synapses occupy 0.72% of the soma surface, the fraction of synaptic labelling was 33-48 (alpha1), 40 (alpha2) and 36 (beta3)% of the total somatic surface immunolabelling. Assuming similar antibody access to all receptors, about 60% of these subunits are in extrasynaptic receptors.}, author = {Kasugai, Yu and Swinny, Jerome D and Roberts, John D and Dalezios, Yannis and Fukazawa, Yugo and Sieghart, Werner C and Ryuichi Shigemoto and Somogyi, Péter}, journal = {European Journal of Neuroscience}, number = {11}, pages = {1868 -- 1888}, publisher = {Wiley-Blackwell}, title = {{Quantitative localisation of synaptic and extrasynaptic GABAA receptor subunits on hippocampal pyramidal cells by freeze-fracture replica immunolabelling}}, doi = {10.1111/j.1460-9568.2010.07473.x}, volume = {32}, year = {2010}, } @article{2510, abstract = {Neurons in the laterocapsular division of the central nucleus of the amygdala (CeC), which is known as the "nociceptive amygdala," receive glutamatergic inputs from the parabrachial nucleus (PB) and the basolateral nucleus of amygdala (BLA), which convey nociceptive information from the dorsal horn of the spinal cord and polymodal information from the thalamus and cortex, respectively. Here, we examined the ultrastructural properties of PB- and BLA-CeC synapses identified with EGFP-expressing lentivirus in rats. In addition, the density of synaptic AMPA receptors (AMPARs) on CeC neurons was studied by using highly sensitive SDS-digested freeze-fracture replica labeling (SDS-FRL). Afferents from the PB made asymmetrical synapses mainly on dendritic shafts (88%), whereas those from the BLA were on dendritic spines (81%). PB-CeC synapses in dendritic shafts were significantly larger (median 0.072 μm 2) than BLA-CeC synapses in spines (median 0.058 μm 2; P = 0.02). The dendritic shafts that made synapses with PB fibers were also significantly larger than those that made synapses with BLA fibers, indicating that the PB fibers make synapses on more proximal parts of dendrites than the BLA fibers. SDS-FRL revealed that almost all excitatory postsynaptic sites have AMPARs in the CeC. The density of AMPAR-specific gold particles in individual synapses was significantly higher in spine synapses (median 510 particles/μm 2) than in shaft synapses (median 427 particles/μm 2; P = 0.01). These results suggest that distinct synaptic impacts from PB- and BLA-CeC pathways contribute to the integration of nociceptive and polymodal information in the CeC.}, author = {Dong, Yu-Lin and Fukazawa, Yugo and Wang, Wen and Kamasawa, Naomi and Ryuichi Shigemoto}, journal = {Journal of Comparative Neurology}, number = {23}, pages = {4771 -- 4791}, publisher = {Wiley-Blackwell}, title = {{Differential postsynaptic compartments in the laterocapsular division of the central nucleus of amygdala for afferents from the parabrachial nucleus and the basolateral nucleus in the rat}}, doi = {10.1002/cne.22487}, volume = {518}, year = {2010}, } @article{2506, abstract = {Subepithelial fibroblasts of the intestinal villi, which form a contractile cellular network beneath the epithelium, are in close contact with epithelial cells, nerve varicosities, capillaries, smooth muscles and immune cells, and secrete extracellular matrix molecules, growth factors and cytokines, etc. Cultured subepithelial fibroblasts of the rat duodenal villi display various receptors such as endothelins, ATP, substance-P and bradykinin, and release ATP in response to mechanical stimulation. In this study, the presence of functional NK1 receptors (NK1R) was pharmacologically confirmed in primary culture by Ca 2+ measurement, and the effects of substance-P were measured in an acute preparation of epithelium-free duodenal villi from 2- to 3-week-old rats using a two-photon laser microscope. Substance-P elicited an increase in the intracellular Ca 2+ concentration and contraction of the subepithelial fibroblasts in culture and the isolated villi. The localization of NK1R and substance-P in the villi was examined by light and electron microscopic immunohistochemistry. NK1R-like immunoreactivity was intensely localized on the plasma membrane of villous subepithelial fibroblasts in 10-day- to 4-week-old rats and mice and was decreased or absent in adulthood. The pericryptal fibroblasts of the small and large intestine were NK1R immuno-negative. These villous subepithelial fibroblasts form synapse-like structures with both substance-P-immunopositive and -immunonegative nerve varicosities. Here, we propose that the mutual interaction between villous subepithelial fibroblasts and afferent neurons via substance-P and ATP plays important roles in the maturation of the structure and function of the small intestine.}, author = {Furuya, Sonoko and Furuya, Kishio and Ryuichi Shigemoto and Sokabe, Masahiro}, journal = {Cell and Tissue Research}, number = {2}, pages = {243 -- 259}, publisher = {Springer}, title = {{Localization of NK1 receptors and roles of substance-P in subepithelial fibroblasts of rat intestinal villi}}, doi = {10.1007/s00441-010-1056-7}, volume = {342}, year = {2010}, } @article{2507, abstract = {T-type calcium channels play a pivotal role in regulating neural membrane excitability in the nervous system. However, the precise subcellular distributions of T-type channel subunits and their implication for membrane excitability are not well understood. Here we investigated the subcellular distribution of the α1G subunit of the calcium channel which is expressed highly in the mouse dorsal lateral geniculate nucleus (dLGN). Light microscopic analysis demonstrated that dLGN exhibits intense immunoperoxidase reactivity for the α1G subunit. Electron microscopic observation showed that the labeling was present in both the relay cells and interneurons and was found in the somatodendritic, but not axonal, domains of these cells. Most of the immunogold particles for the α1G subunit were either associated with the plasma membrane or the intracellular membranes. Reconstruction analysis of serial electron microscopic images revealed that the intensity of the intracellular labeling exhibited a gradient such that the labeling density was higher in the proximal dendrite and progressively decreased towards the distal dendrite. In contrast, the plasma membrane-associated particles were distributed with a uniform density over the somatodendritic surface of dLGN cells. The labeling density in the relay cell plasma membrane was about 3-fold higher than that of the interneurons. These results provide ultrastructural evidence for cell-type-specific expression levels and for uniform expression density of the α1G subunit over the plasma membrane of dLGN cells.}, author = {Parajuli, Laxmi K and Fukazawa, Yugo and Watanabe, Masahiko and Ryuichi Shigemoto}, journal = {Journal of Comparative Neurology}, number = {21}, pages = {4362 -- 4374}, publisher = {Wiley-Blackwell}, title = {{Subcellular distribution of α1G subunit of T-type calcium channel in the mouse dorsal lateral geniculate nucleus}}, doi = {10.1002/cne.22461}, volume = {518}, year = {2010}, } @article{2505, abstract = {Cbln1, secreted from cerebellar granule cells, and the orphan glutamate receptor 52 (GluD2), expressed by Purkinje cells, are essential for synapse integrity between these neurons in adult mice. Nevertheless, no endogenous binding partners for these molecules have been identified. We found that Cblnl binds directly to the N-terminal domain of GluD2. GluD2 expression by postsynaptic cells, combined with exogenously applied Cbln1, was necessary and sufficient to induce new synapses in vitro and in the adult cerebellum in vivo. Further, beads coated with recombinant Cbln1 directly induced presynaptic differentiation and indirectly caused clustering of postsynaptic molecules via GluD2. These results indicate that the Cbln1-GluD2 complex is a unique synapse organizer that acts bidirectionally on both pre- and postsynaptic components.}, author = {Matsuda, Keiko and Miura, Eriko and Miyazaki, Taisuke and Kakegawa, Wataru and Emi, Kyoichi and Narumi, Sakae and Fukazawa, Yugo and Ito-lshida, Aya and Kondo, Tetsuro and Ryuichi Shigemoto and Watanabe, Masahiko and Yuzaki, Michisuke}, journal = {Science}, number = {5976}, pages = {363 -- 368}, publisher = {American Association for the Advancement of Science}, title = {{Cbln1 is a ligand for an orphan glutamate receptor δ2, a bidirectional synapse organizer}}, doi = {10.1126/science.1185152}, volume = {328}, year = {2010}, } @article{2504, abstract = {We present a method for immunolabeling of multiple species of membrane proteins with high spatial resolution. It allows differentiation of equally sized very small markers with different chemical compositions, which leads to high labeling efficiency and reduces steric hindrance of closely spaced immunolabeled biomolecules. Markers such as CdSe/ZnS semiconductor quantum dots and colloidal gold particles are distinguished by differential contrast in high-angle annular detector dark-field STEM mode or by EDX microanalysis of their elemental contents. This method was tested by observation of labeled AMPA- and NMDA-type glutamate receptors on sodium-dodecyl-sulfate-digested replica prepared from rat hippocampus. To improve particle visibility and detectability, the replica films were made exclusively with carbon to avoid the high background of conventional platinum/carbon replica. Extension of the method is suggested by detection of 1.4 nm nanogold particles and its potential application in the biological imaging research.}, author = {Loukanov, Alexandre R and Kamasawa, Naomi and Danev, Radostin S and Ryuichi Shigemoto and Nagayama, Kuniaki}, journal = {Ultramicroscopy}, number = {4}, pages = {366 -- 374}, publisher = {Elsevier}, title = {{Immunolocalization of multiple membrane proteins on a carbon replica with STEM and EDX}}, doi = {10.1016/j.ultramic.2010.01.016}, volume = {110}, year = {2010}, } @article{2704, abstract = {Consider a system of N bosons in three dimensions interacting via a repulsive short range pair potential N2V(N(xi-xj)), where x = (x1, ..., xN) denotes the positions of the particles. Let HN, denote the Hamiltonian of the system and let ψN,t be the solution to the Schrödinger equation. Suppose that the initial data ψN,0 satisfies the energy condition 〈 ψ N,0,Hk N ψN,0〉 ≤ CkNk for k =1, 2, ....We also assume that the k-particle density matrices of the initial state are asymptotically factorized as N →∞1. We prove that the k-particle density matrices of ψN,t are also asymptotically factorized and the one particle orbital wave function solves the Gross-Pitaevskii equation, a cubic nonlinear Schrödinger equation with the coupling constant given by the scattering length of the potential V. We also prove the same conclusion if the energy condition holds only for k=1 but the factorization of ψN,0 is assumed in a stronger sense.}, author = {László Erdös and Schlein, Benjamin and Yau, Horng-Tzer}, journal = {Annals of Mathematics}, number = {1}, pages = {291 -- 370}, publisher = {Princeton University Press}, title = {{Derivation of the Gross-Pitaevskii equation for the dynamics of Bose-Einstein condensate}}, doi = {10.4007/annals.2010.172.291}, volume = {172}, year = {2010}, } @article{2701, abstract = {We consider N × N Hermitian random matrices with independent identically distributed entries (Wigner matrices). The matrices are normalized so that the average spacing between consecutive eigenvalues is of order 1/ N. Under suitable assumptions on the distribution of the single matrix element, we first prove that, away from the spectral edges, the empirical density of eigenvalues concentrates around the Wigner semicircle law on energy scales η ≫ N -1. This result establishes the semicircle law on the optimal scale and it removes a logarithmic factor from our previous result [6]. We then show a Wegner estimate, i.e., that the averaged density of states is bounded. Finally, we prove that the eigenvalues of a Wigner matrix repel each other, in agreement with the universality conjecture.}, author = {László Erdös and Schlein, Benjamin and Yau, Horng-Tzer}, journal = {International Mathematics Research Notices}, number = {3}, pages = {436 -- 479}, publisher = {Oxford University Press}, title = {{Wegner estimate and level repulsion for Wigner random matrices}}, doi = {10.1093/imrn/rnp136}, year = {2010}, } @article{2762, abstract = {We consider N ×N Hermitian Wigner random matrices H where the probabilitydensity for each matrix element is given by the density v(x)=e-U(x). We prove that the eigenvalue statistics in the bulk are given by the Dyson sine kernel provided that U ∈ C 6(R{double-struck}) with at most polynomially growing derivatives and v(x)≤C e-c(x) for x large. The proof is based upon an approximate time reversal of the Dyson Brownian motion combined with the convergence of the eigenvalue density to the Wigner semicircle law on short scales.}, author = {László Erdös and Ramírez, José A and Yau, Horng-Tzer and Péché, Sandrine and Schlein, Benjamin}, journal = {Communications on Pure and Applied Mathematics}, number = {7}, pages = {895 -- 925}, publisher = {Wiley-Blackwell}, title = {{Bulk universality for Wigner matrices}}, doi = {10.1002/cpa.20317}, volume = {63}, year = {2010}, } @article{2761, abstract = {We consider N × N Hermitian random matrices with independent identically distributed entries (Wigner matrices). We assume that the distribution of the entries have a Gaussian component with variance N 3/4+β for some positive β > 0. We prove that the local eigenvalue statistics follows the universal Dyson sine kernel.}, author = {László Erdös and Ramírez, José A and Schlein, Benjamin and Yau, Horng-Tzer}, journal = {Electronic Journal of Probability}, number = {18}, pages = {526 -- 603}, publisher = {Institute of Mathematical Statistics}, title = {{Universality of sine-kernel for Wigner matrices with a small Gaussian perturbation}}, doi = {10.1214/EJP.v15-768}, volume = {15}, year = {2010}, } @article{2756, abstract = {We consider a large atom with nuclear charge Z described by non-relativistic quantum mechanics with classical or quantized electromagnetic field. We prove that the absolute ground state energy, allowing for minimizing over all possible self-generated electromagnetic fields, is given by the non-magnetic Thomas-Fermi theory to leading order in the simultaneous Z → ∞, α → 0 limit if Zα2 ≤ κ for some universal κ, where α is the fine structure constant.}, author = {László Erdös and Solovej, Jan P}, journal = {Communications in Mathematical Physics}, number = {1}, pages = {229 -- 249}, publisher = {Springer}, title = {{Ground state energy of large atoms in a self-generated magnetic field}}, doi = {10.1007/s00220-009-0869-2}, volume = {294}, year = {2010}, } @article{2763, abstract = {In this paper, we consider the ensemble of n×n Wigner Hermitian matrices H = (hℓk)1≤ℓ,k≤n that generalize the Gaussian unitary ensemble (GUE). The matrix elements hℓk = h̄ℓk are given by hℓk = n ?1/2(xℓk + √?1yℓk), where xℓk, yℓk for 1 ≤ ℓ < k ≤ n are i.i.d. random variables with mean zero and variance 1/2, yℓ ℓ = 0 and xℓ ℓ have mean zero and variance 1. We assume the distribution of xℓk, yℓk to have subexponential decay. In [3], four of the authors recently established that the gap distribution and averaged k-point correlation of these matrices were universal (and in particular, agreed with those for GUE) assuming additional regularity hypotheses on the xℓk, yℓk. In [7], the other two authors, using a different method, established the same conclusion assuming instead some moment and support conditions on the xℓk, yℓk. In this short note we observe that the arguments of [3] and [7] can be combined to establish universality of the gap distribution and averaged k-point correlations for all Wigner matrices (with subexponentially decaying entries), with no extra assumptions.}, author = {László Erdös and Ramírez, José A and Schlein, Benjamin and Tao, Terence and Van, Vu and Yau, Horng-Tzer}, journal = {Mathematical Research Letters}, number = {4}, pages = {667 -- 674}, publisher = {International Press}, title = {{Bulk universality for Wigner Hermitian matrices with subexponential decay}}, volume = {17}, year = {2010}, } @article{2798, abstract = {Flows through pipes and channels are the most common means to transport fluids in practical applications and equally occur in numerous natural systems. In general, the transfer of fluids is energetically far more efficient if the motion is smooth and laminar because the friction losses are lower. However, even at moderate velocities pipe and channel flows are sensitive to minute disturbances, and in practice most flows are turbulent. Investigating the motion and spatial distribution of vortices, we uncovered an amplification mechanism that constantly feeds energy from the mean shear into turbulent eddies. At intermediate flow rates, a simple control mechanism suffices to intercept this energy transfer by reducing inflection points in the velocity profile. When activated, an immediate collapse of turbulence is observed, and the flow relaminarizes.}, author = {Björn Hof and de Lózar, Alberto and Avila, Marc and Xiaoyun Tu and Schneider, Tobias M}, journal = {Science}, number = {5972}, pages = {1491 -- 1494}, publisher = {American Association for the Advancement of Science}, title = {{Eliminating turbulence in spatially intermittent flows}}, doi = {10.1126/science.1186091}, volume = {327}, year = {2010}, } @article{2870, abstract = {Dark-grown dicotyledonous seedlings form a hook-like structure at the top of the hypocotyl, which is controlled by the hormones auxin and ethylene. Hook formation is dependent on an auxin signal gradient, whereas hook exaggeration is part of the triple response provoked by ethylene in dark-grown Arabidopsis seedlings. Several other hormones and light are also known to be involved in hook development, but the molecular mechanisms that lead to the initial installation of an auxin gradient are still poorly understood. In this study, we aimed to unravel the cross-talk between auxin and ethylene in the apical hook. Auxin measurements, the expression pattern of the auxin reporter DR5::GUS and the localization of auxin biosynthesis enzymes and influx carriers collectively indicate the necessity for auxin biosynthesis and efficient auxin translocation from the cotyledons and meristem into the hypocotyl in order to support proper hook development. Auxin accumulation in the meristem and cotyledons and in the hypocotyl is increased ∼2-fold upon treatment with ethylene. In addition, a strong ethylene signal leads to enhanced auxin biosynthesis at the inner side of the hook. Finally, mutant analysis demonstrates that the auxin influx carrier LAX3 is indispensable for proper hook formation, whereas the auxin influx carrier AUX1 is involved in the hook exaggeration phenotype induced by ethylene.}, author = {Vandenbussche, Filip and Petrášek, Jan and Žádníková, Petra and Hoyerová, Klára and Pešek, Bedřich and Raz, Vered and Swarup, Ranjan and Bennett, Malcolm and Zažímalová, Eva and Eva Benková and Van Der Straeten, Dominique}, journal = {Development}, number = {4}, pages = {597 -- 606}, publisher = {Company of Biologists}, title = {{The auxin influx carriers AUX1 and LAX3 are involved in auxin-ethylene interactions during apical hook development in Arabidopsis thaliana seedlings}}, doi = {10.1242/dev.040790}, volume = {137}, year = {2010}, } @article{2873, abstract = {Nitrate is both a nitrogen source for higher plants and a signal molecule regulating their development. In Arabidopsis, the NRT1.1 nitrate transporter is crucial for nitrate signaling governing root growth, and has been proposed to act as a nitrate sensor. However, the sensing mechanism is unknown. Herein we show that NRT1.1 not only transports nitrate but also facilitates uptake of the phytohormone auxin. Moreover, nitrate inhibits NRT1.1-dependent auxin uptake, suggesting that transduction of nitrate signal by NRT1.1 is associated with a modification of auxin transport. Among other effects, auxin stimulates lateral root development. Mutation of NRT1.1 enhances both auxin accumulation in lateral roots and growth of these roots at low, but not high, nitrate concentration. Thus, we propose that NRT1.1 represses lateral root growth at low nitrate availability by promoting basipetal auxin transport out of these roots. This defines a mechanism connecting nutrient and hormone signaling during organ development.}, author = {Krouk, Gabriel and Lacombe, Benoît and Bielach, Agnieszka and Perrine-Walker, Francine and Malínská, Kateřina and Mounier, Emmanuelle and Hoyerová, Klára and Tillard, Pascal and Leon, Sarah and Ljung, Karin and Zažímalová, Eva and Eva Benková and Nacry, Philippe and Gojon, Alain}, journal = {Developmental Cell}, number = {6}, pages = {927 -- 937}, publisher = {Cell Press}, title = {{Nitrate-regulated auxin transport by NRT1.1 defines a mechanism for nutrient sensing in plants}}, doi = {10.1016/j.devcel.2010.05.008}, volume = {18}, year = {2010}, } @article{2872, abstract = {Unlike locomotive organisms capable of actively approaching essential resources, sessile plants must efficiently exploit their habitat for water and nutrients. This involves root-mediated underground interactions allowing plants to adapt to soils of diverse qualities. The root system of plants is a dynamic structure that modulates primary root growth and root branching by continuous integration of environmental inputs, such as nutrition availability, soil aeration, humidity, or salinity. Root branching is an extremely flexible means to rapidly adjust the overall surface of the root system and plants have evolved efficient control mechanisms, including, firstly initiation, when and where to start lateral root formation; secondly lateral root primordia organogenesis, during which the development of primordia can be arrested for a certain time; and thirdly lateral root emergence. Our review will focus on the most recent advances in understanding the molecular mechanisms involved in the regulation of lateral root initiation and organogenesis with the main focus on root system of the model plant Arabidopsis thaliana.}, author = {Eva Benková and Bielach, Agnieszka}, journal = {Current Opinion in Plant Biology}, number = {6}, pages = {677 -- 683}, publisher = {Elsevier}, title = {{Lateral root organogenesis - from cell to organ}}, doi = {10.1016/j.pbi.2010.09.006}, volume = {13}, year = {2010}, } @article{2899, abstract = {Toxin–antitoxin (TA) systems are commonly found on bacterial plasmids. The antitoxin inhibits toxin activity unless the system is lost from the cell. Then the shorter lived antitoxin degrades and the cell becomes susceptible to the toxin. Selection for plasmid-encoded TA systems was initially thought to result from their reducing the number of plasmid-free cells arising during growth in monoculture. However, modelling and experiments have shown that this mechanism can only explain the success of plasmid TA systems under a restricted set of conditions. Previously, we have proposed and tested an alternative model explaining the success of plasmid TA systems as a consequence of competition occurring between plasmids during co-infection of bacterial hosts. Here, we test a further prediction of this model, that competition between plasmids will lead to the biased accumulation of TA systems on plasmids relative to chromosomes. Transposon-encoded TA systems were added to populations of plasmid-containing cells, such that TA systems could insert into either plasmids or chromosomes. These populations were enriched for transposon-containing cells and then incubated in environments that did, or did not, allow effective within-host plasmid competition to occur. Changes in the ratio of plasmid- to chromosome-encoded TA systems were monitored. In agreement with our model, we found that plasmid-encoded TA systems had a competitive advantage, but only when host cells were sensitive to the effect of TA systems. This result demonstrates that within-host competition between plasmids can select for TA systems.}, author = {Cooper, Tim F and Tiago Paixao and Heinemann, Jack A}, journal = {Proc R Soc B}, number = {1697}, pages = {3149 -- 3155}, publisher = {Wiley-Blackwell}, title = {{Within host competition selects for plasmid encoded toxin–antitoxin systems}}, doi = {10.1098/rspb.2010.0831}, volume = {277}, year = {2010}, } @inproceedings{2979, abstract = {Zero-knowledge proofs of knowledge (ZK-PoK) are important building blocks for numerous cryptographic applications. Although ZK-PoK have a high potential impact, their real world deployment is typically hindered by their significant complexity compared to other (non-interactive) crypto primitives. Moreover, their design and implementation are time-consuming and error-prone. We contribute to overcoming these challenges as follows: We present a comprehensive specification language and a compiler for ZK-PoK protocols based on Σ-protocols. The compiler allows the fully automatic translation of an abstract description of a proof goal into an executable implementation. Moreover, the compiler overcomes various restrictions of previous approaches, e.g., it supports the important class of exponentiation homomorphisms with hidden-order co-domain, needed for privacy-preserving applications such as DAA. Finally, our compiler is certifying, in the sense that it automatically produces a formal proof of the soundness of the compiled protocol for a large class of protocols using the Isabelle/HOL theorem prover. }, author = {Almeida, José Bacelar and Bangerter, Endre and Barbosa, Manuel and Stephan Krenn and Sadeghi, Ahmad-Reza and Schneider, Thomas}, editor = {Gritzalis, Dimitris and Preneel, Bart and Theoharidou, Marianthi}, pages = {151 -- 167}, publisher = {Springer}, title = {{A Certifying Compiler for Zero-Knowledge Proofs of Knowledge Based on Sigma-Protocols}}, doi = {10.1007/978-3-642-15497-3}, volume = {6345}, year = {2010}, } @inproceedings{2980, abstract = {Efficient zero-knowledge proofs of knowledge (ZK-PoK) are basic building blocks of many practical cryptographic applications such as identification schemes, group signatures, and secure multi-party computation (SMPC). Currently, first applications that essentially rely on ZK-PoKs are being deployed in the real world. The most prominent example is the Direct Anonymous Attestation (DAA) protocol, which was adopted by the Trusted Computing Group (TCG) and implemented as one of the functionalities of the cryptographic chip Trusted Platform Module (TPM). Implementing systems using ZK-PoK turns out to be challenging, since ZK-PoK are significantly more complex than standard crypto primitives (e.g., encryption and signature schemes). As a result, the design-implementation cycles of ZK-PoK are time-consuming and error-prone. To overcome this, we present a compiler with corresponding languages for the automatic generation of sound and efficient ZK-PoK based on Σ-protocols. The protocol designer using our compiler formulates the goal of a ZK-PoK proof in a high-level protocol specification language, which abstracts away unnecessary technicalities from the designer. The compiler then automatically generates the protocol implementation in Java code; alternatively, the compiler can output a description of the protocol in LaTeX which can be used for documentation or verification.}, author = {Bangerter, Endre and Briner, Thomas and Henecka, Wilko and Stephan Krenn and Sadeghi, Ahmad-Reza and Schneider, Thomas}, editor = {Martinelli, Fabio and Preneel, Bart}, pages = {67 -- 82}, publisher = {Springer}, title = {{Automatic Generation of Sigma-Protocols}}, doi = {10.1007/978-3-642-16441-5}, volume = {6391}, year = {2010}, } @inproceedings{2978, abstract = {Efficient zero-knowledge proofs of knowledge for group homomorphisms are essential for numerous systems in applied cryptography. Especially, Σ-protocols for proving knowledge of discrete logarithms in known and hidden order groups are of prime importance. Yet, while these proofs can be performed very efficiently within groups of known order, for hidden order groups the respective proofs are far less efficient. This paper shows strong evidence that this efficiency gap cannot be bridged. Namely, while there are efficient protocols allowing a prover to cheat only with negligibly small probability in the case of known order groups, we provide strong evidence that for hidden order groups this probability is bounded below by 1/2 for all efficient Σ-protocols not using common reference strings or the like. We prove our results for a comprehensive class of Σ-protocols in the generic group model, and further strengthen them by investigating certain instantiations in the plain model.}, author = {Bangerter, Endre and Camenisch, Jan and Stephan Krenn}, editor = {Micciancio, Daniele}, pages = {553 -- 571}, publisher = {Springer}, title = {{Efficiency Limitations for Σ-Protocols for Group Homomorphisms}}, doi = {10.1007/978-3-642-11799-2}, volume = {5978}, year = {2010}, } @article{3062, abstract = {Development in multicellular organisms depends on the ability of individual cells to coordinate their behavior by means of small signaling molecules to form correctly patterned tissues. In plants, a unique mechanism of directional transport of the signaling molecule auxin between cells connects cell polarity and tissue patterning and thus is required for many aspects of plant development. Direction of auxin flow is determined by polar subcellular localization of PIN auxin efflux transporters. Dynamic PIN polar localization results from the constitutive endocytic cycling to and from the plasma membrane, but it is not well understood how this mechanism connects to regulators of cell polarity. The Rho family small GTPases ROPs/RACs are master regulators of cell polarity, however their role in regulating polar protein trafficking and polar auxin transport has not been established. Here, by analysis of mutants and transgenic plants, we show that the ROP interactor and polarity regulator scaffold protein ICR1 is required for recruitment of PIN proteins to the polar domains at the plasma membrane. icr1 mutant embryos and plants display an a array of severe developmental aberrations that are caused by compromised differential auxin distribution. ICR1 functions at the plasma membrane where it is required for exocytosis but does not recycle together with PINs. ICR1 expression is quickly induced by auxin but is suppressed at the positions of stable auxin maxima in the hypophysis and later in the embryonic and mature root meristems. Our results imply that ICR1 is part of an auxin regulated positive feedback loop realized by a unique integration of auxin-dependent transcriptional regulation into ROP-mediated modulation of cell polarity. Thus, ICR1 forms an auxin-modulated link between cell polarity, exocytosis, and auxin transport-dependent tissue patterning.}, author = {Hazak, Ora and Bloch, Daria and Poraty, Limor and Sternberg, Hasana and Zhang, Jing and Jirí Friml and Yalovsky, Shaul}, journal = {PLoS Biology}, number = {1}, publisher = {Public Library of Science}, title = {{A Rho scaffold integrates the secretory system with feedback mechanisms in regulation of auxin distribution}}, doi = {10.1371/journal.pbio.1000282}, volume = {8}, year = {2010}, } @article{3073, abstract = {Polar membrane cargo delivery is crucial for establishing cell polarity and for directional transport processes. In plants, polar trafficking mediates the dynamic asymmetric distribution of PIN FORMED (PIN) carriers, which drive polar cell-to-cell transport of the hormone auxin, thereby generating auxin maxima and minima that control development. The Arabidopsis PINOID (PID) protein kinase instructs apical PIN localization by phosphorylating PINs. Here, we identified the PID homologs WAG1 and WAG2 as new PIN polarity regulators. We show that the AGC3 kinases PID, WAG1 and WAG2, and not other plant AGC kinases, instruct recruitment of PINs into the apical recycling pathway by phosphorylating the middle serine in three conserved TPRXS(N/S) motifs within the PIN central hydrophilic loop. Our results put forward a model by which apolarly localized PID, WAG1 and WAG2 phosphorylate PINs at the plasma membrane after default non-polar PIN secretion, and trigger endocytosis-dependent apical PIN recycling. This phosphorylation-triggered apical PIN recycling competes with ARF-GEF GNOM-dependent basal recycling to promote apical PIN localization. In planta, expression domains of PID, WAG1 and WAG2 correlate with apical localization of PINs in those cell types, indicating the importance of these kinases for apical PIN localization. Our data show that by directing polar PIN localization and PIN-mediated polar auxin transport, the three AGC3 kinases redundantly regulate cotyledon development, root meristem size and gravitropic response, indicating their involvement in both programmed and adaptive plant development.}, author = {Dhonukshe, Pankaj and Huang, Fang and Galván Ampudia, Carlos and Mähönen, Ari and Kleine Vehn, Jürgen and Xu, Jian and Quint, Ab and Prasad, Kalika and Friml, Jiřĺ and Scheres, Ben and Offringa, Remko}, journal = {Development}, number = {19}, pages = {3245 -- 3255}, publisher = {Company of Biologists}, title = {{Plasma membrane-bound AGC3 kinases phosphorylate PIN auxin carriers at TPRXS(N/S) motifs to direct apical PIN recycling}}, doi = {10.1242/dev.052456}, volume = {137}, year = {2010}, } @article{3072, abstract = {Development of plants and their adaptive capacity towards ever‐changing environmental conditions largely depend on the spatial distribution of the plant hormone auxin. At the cellular level, various internal and external signals are translated into specific changes in the polar, subcellular localization of auxin transporters from the PIN family thereby directing and redirecting the intercellular fluxes of auxin. The current model of polar targeting of PIN proteins towards different plasma membrane domains encompasses apolar secretion of newly synthesized PINs followed by endocytosis and recycling back to the plasma membrane in a polarized manner. In this review, we follow the subcellular march of the PINs and highlight the cellular and molecular mechanisms behind polar foraging and subcellular trafficking pathways. Also, the entry points for different signals and regulations including by auxin itself will be discussed within the context of morphological and developmental consequences of polar targeting and subcellular trafficking.}, author = {Grunewald, Wim and Friml, Jirí}, journal = {EMBO Journal}, number = {16}, pages = {2700 -- 2714}, publisher = {Wiley-Blackwell}, title = {{The march of the PINs: Developmental plasticity by dynamic polar targeting in plant cells}}, doi = {10.1038/emboj.2010.181}, volume = {29}, year = {2010}, } @article{3079, abstract = {Plant development is exceptionally flexible as manifested by its potential for organogenesis and regeneration, which are processes involving rearrangements of tissue polarities. Fundamental questions concern how individual cells can polarize in a coordinated manner to integrate into the multicellular context. In canalization models, the signaling molecule auxin acts as a polarizing cue, and feedback on the intercellular auxin flow is key for synchronized polarity rearrangements. We provide a novel mechanistic framework for canalization, based on up-to-date experimental data and minimal, biologically plausible assumptions. Our model combines the intracellular auxin signaling for expression of PINFORMED (PIN) auxin transporters and the theoretical postulation of extracellular auxin signaling for modulation of PIN subcellular dynamics. Computer simulations faithfully and robustly recapitulated the experimentally observed patterns of tissue polarity and asymmetric auxin distribution during formation and regeneration of vascular systems and during the competitive regulation of shoot branching by apical dominance. Additionally, our model generated new predictions that could be experimentally validated, highlighting a mechanistically conceivable explanation for the PIN polarization and canalization of the auxin flow in plants.}, author = {Krzysztof Wabnik and Kleine-Vehn, Jürgen and Balla, Jozef and Sauer, Michael and Naramoto, Satoshi and Reinöhl, Vilém and Merks, Roeland M and Govaerts, Willy J and Jirí Friml}, journal = {Molecular Systems Biology}, publisher = {Nature Publishing Group}, title = {{Emergence of tissue polarization from synergy of intracellular and extracellular auxin signaling}}, doi = {10.1038/msb.2010.103}, volume = {6}, year = {2010}, } @article{3075, abstract = { Spatial distribution of the plant hormone auxin regulates multiple aspects of plant development. These self-regulating auxin gradients are established by the action of PIN auxin transporters, whose activity is regulated by their constitutive cycling between the plasma membrane and endosomes. Here, we show that auxin signaling by the auxin receptor AUXIN-BINDING PROTEIN 1 (ABP1) inhibits the clathrin-mediated internalization of PIN proteins. ABP1 acts as a positive factor in clathrin recruitment to the plasma membrane, thereby promoting endocytosis. Auxin binding to ABP1 interferes with this action and leads to the inhibition of clathrin-mediated endocytosis. Our study demonstrates that ABP1 mediates a nontranscriptional auxin signaling that regulates the evolutionarily conserved process of clathrin-mediated endocytosis and suggests that this signaling may be essential for the developmentally important feedback of auxin on its own transport.}, author = {Robert, Stéphanie and Kleine-Vehn, Jürgen and Barbez, Elke and Sauer, Michael and Paciorek, Tomasz and Pawel Baster and Vanneste, Steffen and Zhang, Jing and Sibu Simon and Čovanová, Milada and Hayashi, Kenichiro and Dhonukshe, Pankaj and Yang, Zhenbiao and Bednarek, Sebastian Y and Jones, Alan M and Luschnig, Christian and Aniento, Fernando and Zažímalová, Eva and Jirí Friml}, journal = {Cell}, number = {1}, pages = {111 -- 121}, publisher = {Cell Press}, title = {{ABP1 mediates auxin inhibition of clathrin-dependent endocytosis in Arabidopsis}}, doi = {10.1016/j.cell.2010.09.027}, volume = {143}, year = {2010}, } @inbook{3078, abstract = {Rapid advances in the field of plant biology, especially in plant cell biology, have created the need for methods that allow the localization of proteins in situ at subcellular resolution. Although in many cases recombinant proteins with fluorescent proteins can fulfill this task, antibody-based immunological detection of proteins is a complementary technique, which avoids the risk of inducing side effects by a fusion protein, such as misexpression, mistargeting, altered stability, or toxicity. Moreover, recombinant protein techniques are applicable only to a rather limited set of model plants. The immunolocalization protocols presented here can be used to display protein localization patterns in different tissues of various plant species. This chapter describes a whole mount immunolocalization protocol, which has been extensively used in Arabidopsis roots and some above-ground tissues, and that also works in other species. Additionally, for bulky or hard tissue types, a variation of this protocol for paraffin-embedded sections is given.}, author = {Sauer, Michael and Jirí Friml}, booktitle = {Plant Developmental Biology}, editor = {Hennig, Lars and Köhler, Claudia}, pages = {253 -- 263}, publisher = {Humana Press}, title = {{Immunolocalization of proteins in plants }}, doi = {10.1007/978-1-60761-765-5_17}, volume = {655}, year = {2010}, } @article{3071, abstract = {Plant vacuoles are essential multifunctional organelles largely distinct from similar organelles in other eukaryotes. Embryo protein storage vacuoles and the lytic vacuoles that perform a general degradation function are the best characterized, but little is known about the biogenesis and transition between these vacuolar types. Here, we designed a fluorescent marker- based forward genetic screen in Arabidopsis thaliana and identified a protein affected trafficking2 (pat2) mutant, whose lytic vacuoles display altered morphology and accumulation of proteins. Unlike other mutants affecting the vacuole, pat2 is specifically defective in the biogenesis, identity, and function of lytic vacuoles but shows normal sorting of proteins to storage vacuoles. PAT2 encodes a putative β-subunit of adaptor protein complex 3 (AP-3) that can partially complement the corresponding yeast mutant. Manipulations of the putative AP-3 β adaptin functions suggest a plant-specific role for the evolutionarily conserved AP-3 β in mediating lytic vacuole performance and transition of storage into the lytic vacuoles independently of the main prevacuolar compartment-based trafficking route.}, author = {Feraru, Elena and Paciorek, Tomasz and Feraru, Mugurel I and Zwiewka, Marta and De Groodt, Ruth and De Rycke, Riet M and Kleine-Vehn, Jürgen and Jirí Friml}, journal = {Plant Cell}, number = {8}, pages = {2812 -- 2824}, publisher = {American Society of Plant Biologists}, title = {{The AP 3 β adaptin mediates the biogenesis and function of lytic vacuoles in Arabidopsis}}, doi = {10.1105/tpc.110.075424}, volume = {22}, year = {2010}, } @article{3074, abstract = {Auxin is an essential phytohormone that regulates many aspects of plant development. To identify new genes that function in auxin signaling, we performed a genetic screen for Arabidopsis thaliana mutants with an alteration in the expression of the auxin-responsive reporter DR5rev:GFP (for green fluorescent protein). One of the mutants recovered in this screen, called weak auxin response1 (wxr1), has a defect in auxin response and exhibits a variety of auxin-related growth defects in the root. Polar auxin transport is reduced in wxr1 seedlings, resulting in auxin accumulation in the hypocotyl and cotyledons and a reduction in auxin levels in the root apex. In addition, the levels of the PIN auxin transport proteins are reduced in the wxr1 root. We also show that WXR1 is ROOT UV-B SENSITIVE2 (RUS2), a member of the broadly conserved DUF647 domain protein family found in diverse eukaryotic organisms. Our data indicate that RUS2/WXR1 is required for auxin transport and to maintain the normal levels of PIN proteins in the root.}, author = {Ge, Lei and Peer, Wendy A and Robert, Stéphanie and Swarup, Ranjan and Ye, Songqing and Prigge, Michael J and Cohen, Jerry D and Jirí Friml and Murphy, Angus S and Tang, Ding and Estelle, Mark A}, journal = {Plant Cell}, number = {6}, pages = {1749 -- 1761}, publisher = {American Society of Plant Biologists}, title = {{Arabidopsis ROOT UVB SENSITIVE2 WEAK AUXIN RESPONSE1 is required for polar auxin transport}}, doi = {10.1105/tpc.110.074195}, volume = {22}, year = {2010}, } @article{3076, abstract = {Auxin is a multifunctional hormone essential for plant development and pattern formation. A nuclear auxin-signaling system controlling auxin-induced gene expression is well established, but cytoplasmic auxin signaling, as in its coordination of cell polarization, is unexplored. We found a cytoplasmic auxin-signaling mechanism that modulates the interdigitated growth of Arabidopsis leaf epidermal pavement cells (PCs), which develop interdigitated lobes and indentations to form a puzzle-piece shape in a two-dimensional plane. PC interdigitation is compromised in leaves deficient in either auxin biosynthesis or its export mediated by PINFORMED 1 localized at the lobe tip. Auxin coordinately activates two Rho GTPases, ROP2 and ROP6, which promote the formation of complementary lobes and indentations, respectively. Activation of these ROPs by auxin occurs within 30 s and depends on AUXIN-BINDING PROTEIN 1. These findings reveal Rho GTPase-based auxin-signaling mechanisms, which modulate the spatial coordination of cell expansion across a field of cells.}, author = {Xu, Tongda and Wen, Mingzhang and Nagawa, Shingo and Fu, Ying and Chen, Jin-Gui and Wu, Ming-Jing and Perrot-Rechenmann, Catherine and Jirí Friml and Jones, Alan M and Yang, Zhenbiao}, journal = {Cell}, number = {1}, pages = {99 -- 110}, publisher = {Cell Press}, title = {{Cell surface- and Rho GTPase-based auxin signaling controls cellular interdigitation in Arabidopsis}}, doi = {10.1016/j.cell.2010.09.003}, volume = {143}, year = {2010}, } @article{3077, author = {Friml, Jirí and Jones, Angharad}, journal = {Plant Physiology}, number = {2}, pages = {458 -- 462}, publisher = {American Society of Plant Biologists}, title = {{Endoplasmic reticulum: The rising compartment in auxin biology}}, doi = {10.1104/pp.110.161380}, volume = {154}, year = {2010}, } @article{3146, abstract = {Coordinated migration of newly born neurons to their prospective target laminae is a prerequisite for neural circuit assembly in the developing brain. The evolutionarily conserved LIS1/NDEL1 complex is essential for neuronal migration in the mammalian cerebral cortex. The cytoplasmic nature of LIS1 and NDEL1 proteins suggest that they regulate neuronal migration cell autonomously. Here, we extend mosaic analysis with double markers (MADM) to mouse chromosome 11 where Lis1, Ndel1, and 14-3-3e{open} (encoding a LIS1/NDEL1 signaling partner) are located. Analyses of sparse and uniquely labeled mutant cells in mosaic animals reveal distinct cell-autonomous functions for these three genes. Lis1 regulates neuronal migration efficiency in a dose-dependent manner, while Ndel1 is essential for a specific, previously uncharacterized, late step of neuronal migration: entry into the target lamina. Comparisons with previous genetic perturbations of Lis1 and Ndel1 also suggest a surprising degree of cell-nonautonomous function for these proteins in regulating neuronal migration.}, author = {Simon Hippenmeyer and Youn, Yong H and Moon, Hyang M and Miyamichi, Kazunari and Zong, Hui and Wynshaw-Boris, Anthony and Luo, Liqun}, journal = {Neuron}, number = {4}, pages = {695 -- 709}, publisher = {Elsevier}, title = {{Genetic mosaic dissection of Lis1 and Ndel1 in neuronal migration}}, doi = {10.1016/j.neuron.2010.09.027}, volume = {68}, year = {2010}, } @article{3202, abstract = {We consider the following problem: given an undirected weighted graph G = (V,E,c) with nonnegative weights, minimize function c(δ(Π))- λ|Π| for all values of parameter λ. Here Π is a partition of the set of nodes, the first term is the cost of edges whose endpoints belong to different components of the partition, and |Π| is the number of components. The current best known algorithm for this problem has complexity O(|V| 2) maximum flow computations. We improve it to |V| parametric maximum flow computations. We observe that the complexity can be improved further for families of graphs which admit a good separator, e.g. for planar graphs.}, author = {Vladimir Kolmogorov}, journal = {Algorithmica}, number = {4}, pages = {394 -- 412}, publisher = {Springer}, title = {{A faster algorithm for computing the principal sequence of partitions of a graph}}, doi = {10.1007/s00453-008-9177-z}, volume = {56}, year = {2010}, } @inproceedings{10909, abstract = {We address the problem of localizing homology classes, namely, finding the cycle representing a given class with the most concise geometric measure. We focus on the volume measure, that is, the 1-norm of a cycle. Two main results are presented. First, we prove the problem is NP-hard to approximate within any constant factor. Second, we prove that for homology of dimension two or higher, the problem is NP-hard to approximate even when the Betti number is O(1). A side effect is the inapproximability of the problem of computing the nonbounding cycle with the smallest volume, and computing cycles representing a homology basis with the minimal total volume. We also discuss other geometric measures (diameter and radius) and show their disadvantages in homology localization. Our work is restricted to homology over the ℤ2 field.}, author = {Chen, Chao and Freedman, Daniel}, booktitle = {Proceedings of the 2010 Annual ACM-SIAM Symposium on Discrete Algorithms}, location = {Austin, TX, United States}, pages = {1594--1604}, publisher = {Society for Industrial and Applied Mathematics}, title = {{Hardness results for homology localization}}, doi = {10.1137/1.9781611973075.129}, year = {2010}, } @article{3303, abstract = {Biological traits result in part from interactions between different genetic loci. This can lead to sign epistasis, in which a beneficial adaptation involves a combination of individually deleterious or neutral mutations; in this case, a population must cross a “fitness valley” to adapt. Recombination can assist this process by combining mutations from different individuals or retard it by breaking up the adaptive combination. Here, we analyze the simplest fitness valley, in which an adaptation requires one mutation at each of two loci to provide a fitness benefit. We present a theoretical analysis of the effect of recombination on the valley-crossing process across the full spectrum of possible parameter regimes. We find that low recombination rates can speed up valley crossing relative to the asexual case, while higher recombination rates slow down valley crossing, with the transition between the two regimes occurring when the recombination rate between the loci is approximately equal to the selective advantage provided by the adaptation. In large populations, if the recombination rate is high and selection against single mutants is substantial, the time to cross the valley grows exponentially with population size, effectively meaning that the population cannot acquire the adaptation. Recombination at the optimal (low) rate can reduce the valley-crossing time by up to several orders of magnitude relative to that in an asexual population. }, author = {Weissman, Daniel and Feldman, Marcus and Fisher, Daniel}, journal = {Genetics}, number = {4}, pages = {1389 -- 1410}, publisher = {Genetics Society of America}, title = {{The rate of fitness-valley crossing in sexual populations}}, doi = {10.1534/genetics.110.123240}, volume = {186}, year = {2010}, } @article{3407, abstract = {Genetically targeted light-activated ion channels and pumps make it possible to determine the role of specific neurons in neuronal circuits, information processing and behavior. We developed a K+-selective ionotropic glutamate receptor that reversibly inhibits neuronal activity in response to light in dissociated neurons and brain slice and also reversibly suppresses behavior in zebrafish. The receptor is a chimera of the pore region of a K+-selective bacterial glutamate receptor and the ligand-binding domain of a light-gated mammalian kainate receptor. This hyperpolarizing light-gated channel, HyLighter, is turned on by a brief light pulse at one wavelength and turned off by a pulse at a second wavelength. The control is obtained at moderate intensity. After optical activation, the photocurrent and optical silencing of activity persists in the dark for extended periods. The low light requirement and bi-stability of HyLighter represent advantages for the dissection of neural circuitry.}, author = {Harald Janovjak and Szobota, Stephanie and Wyart, Claire and Trauner, Dirk and Isacoff, Ehud Y}, journal = {Nature Neuroscience}, pages = {1027 -- 1032}, publisher = {Nature Publishing Group}, title = {{A light-gated, potassium-selective glutamate receptor for the optical inhibition of neuronal firing}}, doi = {10.1038/nn.2589}, volume = {13}, year = {2010}, } @misc{3406, abstract = {The impact of structural biology on the design of ligands (agonists, antagonists and modulators) for ionotropic glutamate receptors is reviewed.}, author = {Stawski, Philipp and Harald Janovjak and Trauner, Dirk}, booktitle = {Bioorganic and Medicinal Chemistry}, number = {22}, pages = {7759 -- 7772}, publisher = {Elsevier}, title = {{Pharmacology of ionotropic glutamate receptors: a structural perspective}}, doi = {10.1016/j.bmc.2010.09.012}, volume = {18}, year = {2010}, }