@article{1334, abstract = {Hippocampal neurons encode a cognitive map of space. These maps are thought to be updated during learning and in response to changes in the environment through activity-dependent synaptic plasticity. Here we examine how changes in activity influence spatial coding in rats using halorhodopsin-mediated, spatially selective optogenetic silencing. Halorhoposin stimulation leads to light-induced suppression in many place cells and interneurons; some place cells increase their firing through disinhibition, whereas some show no effect. We find that place fields of the unaffected subpopulation remain stable. On the other hand, place fields of suppressed place cells were unstable, showing remapping across sessions before and after optogenetic inhibition. Disinhibited place cells had stable maps but sustained an elevated firing rate. These findings suggest that place representation in the hippocampus is constantly governed by activity-dependent processes, and that disinhibition may provide a mechanism for rate remapping.}, author = {Schönenberger, Philipp and O'Neill, Joseph and Csicsvari, Jozsef L}, journal = {Nature Communications}, publisher = {Nature Publishing Group}, title = {{Activity dependent plasticity of hippocampal place maps}}, doi = {10.1038/ncomms11824}, volume = {7}, year = {2016}, } @inproceedings{1335, abstract = {In this paper we review various automata-theoretic formalisms for expressing quantitative properties. We start with finite-state Boolean automata that express the traditional regular properties. We then consider weighted ω-automata that can measure the average density of events, which finite-state Boolean automata cannot. However, even weighted ω-automata cannot express basic performance properties like average response time. We finally consider two formalisms of weighted ω-automata with monitors, where the monitors are either (a) counters or (b) weighted automata themselves. We present a translation result to establish that these two formalisms are equivalent. Weighted ω-automata with monitors generalize weighted ω-automata, and can express average response time property. They present a natural, robust, and expressive framework for quantitative specifications, with important decidable properties.}, author = {Chatterjee, Krishnendu and Henzinger, Thomas A and Otop, Jan}, location = {Edinburgh, United Kingdom}, pages = {23 -- 38}, publisher = {Springer}, title = {{Quantitative monitor automata}}, doi = {10.1007/978-3-662-53413-7_2}, volume = {9837}, year = {2016}, } @article{21099, abstract = {Quinoline‐based oligoamide foldamers have been identified as a potent class of ligands for G‐quadruplex DNA. Their helical structure is thought to target G‐quadruplex loops or grooves and not G‐tetrads. We report a co‐crystal structure of the antiparallel hairpin dimeric DNA G‐quadruplex (G4T4G4)2 with tetramer 1a helically folded oligo‐quinolinecarboxamide bearing cationic side chains—that is consistent with this hypothesis. Multivalent foldamer-DNA interactions that modify the packing of (G4T4G4)2 in the solid state are observed.}, author = {Mandal, Pradeep K and Baptiste, Benoît and Langlois d'Estaintot, Béatrice and Kauffmann, Brice and Huc, Ivan}, issn = {1439-7633}, journal = {ChemBioChem}, number = {20}, pages = {1911--1914}, publisher = {Wiley}, title = {{Multivalent interactions between an aromatic helical foldamer and a DNA G‐quadruplex in the solid state}}, doi = {10.1002/cbic.201600281}, volume = {17}, year = {2016}, } @article{21100, abstract = {Using commercial screens for crystallization of biomolecules and taking advantage of the use of racemic crystallography allowed the production of X-ray quality single crystals and the elucidation at 1.08 Å resolution of the solid state structure of a difficult target: the complex between glucopyranose and a water soluble macrocyclic receptor equipped with dendritic multianionic solubilizing chains.}, author = {Mandal, Pradeep K and Kauffmann, Brice and Destecroix, Harry and Ferrand, Yann and Davis, Anthony P. and Huc, Ivan}, issn = {1364-548X}, journal = {Chemical Communications}, number = {60}, pages = {9355--9358}, publisher = {Royal Society of Chemistry}, title = {{Crystal structure of a complex between β-glucopyranose and a macrocyclic receptor with dendritic multicharged water solubilizing chains}}, doi = {10.1039/c6cc04466b}, volume = {52}, year = {2016}, } @article{21101, abstract = {It has previously been shown that the use of racemic mixtures of naturally chiral macromolecules such as protein and DNA can significantly aid the crystallogenesis process, thereby addressing one of the major bottlenecks to structure determination by X-ray crystallographic methods—that of crystal growth. Although previous studies have provided convincing evidence of the applicability of the racemic crystallization technique to DNA through the study of well-characterized DNA structures, we sought to apply this method to a historically challenging DNA sequence. For this purpose we chose a non-self-complementary DNA duplex containing the biologically-relevant Pribnow box consensus sequence ‘TATAAT’. Four racemic crystal structures of this previously un-crystallizable DNA target are reported (with resolutions in the range of 1.65–2.3 Å), with further crystallographic studies and structural analysis providing insight into the racemic crystallization process as well as structural details of this highly pertinent DNA sequence.}, author = {Mandal, Pradeep K and Collie, Gavin W. and Srivastava, Suresh C. and Kauffmann, Brice and Huc, Ivan}, issn = {1362-4962}, journal = {Nucleic Acids Research}, number = {12}, pages = {5936--5943}, publisher = {Oxford University Press}, title = {{Structure elucidation of the Pribnow box consensus promoter sequence by racemic DNA crystallography}}, doi = {10.1093/nar/gkw367}, volume = {44}, year = {2016}, } @article{21522, abstract = {In this Letter, we demonstrate highly efficient, polarization-insensitive planar lenses (metalenses) at red, green, and blue wavelengths (λ = 660, 532, and 405 nm). Metalenses with numerical apertures (NA) of 0.85 and 0.6 and corresponding efficiencies as high as 60% and 90% are achieved. These metalenses are less than 600 nm-thick and can focus incident light down to diffraction-limited spots as small as ∼0.64λ and provide high-resolution imaging. In addition, the focal spots are very symmetric with high Strehl ratios. The single step lithography and compatibility with large-scale fabrication processes make metalenses highly promising for widespread applications in imaging and spectroscopy.}, author = {Khorasaninejad, M. and Zhu, A. Y. and Roques-Carmes, Charles and Chen, W. T. and Oh, J. and Mishra, I. and Devlin, R. C. and Capasso, F.}, issn = {1530-6992}, journal = {Nano Letters}, keywords = {Metasurface, polarization-insensitive metalenses, visible wavelength, titanium dioxide}, number = {11}, pages = {7229--7234}, publisher = {American Chemical Society}, title = {{Polarization-insensitive metalenses at visible wavelengths}}, doi = {10.1021/acs.nanolett.6b03626}, volume = {16}, year = {2016}, } @inproceedings{21635, abstract = {We report high numerical aperture meta-lenses in the visible spectrum with focal spots as small as 0.65λ. Meta-lenses are based on ultra-thin titanium dioxide metasurface phase masks. They operate in transmission mode and are polarization-insensitive.}, author = {Khorasaninejad, M. and Chen, W. T. and Zhu, A. and Oh, J. and Roques-Carmes, Charles and Mishra, I. and Devlin, R. C. and Capasso, F.}, booktitle = {Frontiers in Optics 2016}, location = {Rochester, NY, United States}, publisher = {Optica Publishing Group}, title = {{High numerical aperture meta-lenses at visible wavelengths}}, doi = {10.1364/fio.2016.jw4a.63}, year = {2016}, } @article{21812, abstract = {We report a facile strategy to grow supramolecular copolymers on Au surfaces by successively exposing a surface‐anchored monomer to solutions of oppositely charged peptide comonomers. Charge regulation on the active chain end of the polymer sufficiently slows down the kinetics of the self‐assembly process to produce kinetically trapped copolymers at near‐neutral pH. We thereby achieve architectural control at three levels: The β‐sheet sequences direct the polymerization away from the surface, the height of the supramolecular copolymer brushes is well‐controlled by the stepwise nature of the alternating copolymer growth, and 2D spatial resolution is realized by using micropatterned initiating monomers. The programmable nature of the resulting architectures renders this concept attractive for the development of customized biomaterials or chiral interfaces for optoelectronics and sensor applications.}, author = {Frisch, Hendrik and Fritz, Eva‐Corinna and Stricker, Friedrich J and Schmüser, Lars and Spitzer, Daniel and Weidner, Tobias and Ravoo, Bart Jan and Besenius, Pol}, issn = {1521-3773}, journal = {Angewandte Chemie International Edition}, number = {25}, pages = {7242--7246}, publisher = {Wiley}, title = {{Kinetically controlled sequential growth of surface‐grafted chiral supramolecular copolymers}}, doi = {10.1002/anie.201601048}, volume = {55}, year = {2016}, } @misc{21815, abstract = {A modular strategy for the synthesis of surface-confined supramolecular copolymers is reported by P. Besenius, B. J. Ravoo, and co-workers in their Communication on page 7242 ff. The sequential addition of aqueous solutions containing the anionic or cationic comonomer enables the stepwise growth of alternating copolymers from gold surfaces. Charge regulation passivates the growing chain end and yields kinetically trapped chiral copolymers with a tunable height of 5–19 nm.}, author = {Frisch, Hendrik and Fritz, Eva‐Corinna and Stricker, Friedrich J and Schmüser, Lars and Spitzer, Daniel and Weidner, Tobias and Ravoo, Bart Jan and Besenius, Pol}, booktitle = {Angewandte Chemie International Edition}, issn = {1521-3773}, number = {25}, pages = {7009--7264}, publisher = {Wiley}, title = {{Inside back cover: Kinetically controlled sequential growth of surface‐grafted chiral supramolecular Copolymers (Angew. Chem. Int. Ed. 25/2016)}}, doi = {10.1002/anie.201604416}, volume = {55}, year = {2016}, } @article{13385, abstract = {Novel light-responsive nanoparticles were synthesized by decorating the surfaces of gold and silver nanoparticles with a nitrospiropyran molecular photoswitch. Upon exposure to UV light in nonpolar solvents, these nanoparticles self-assembled to afford spherical aggregates, which disassembled rapidly when the UV stimulus was turned off. The sizes of these aggregates depended on the nanoparticle concentration, and their lifetimes could be controlled by adjusting the surface concentration of nitrospiropyran on the nanoparticles. The conformational flexibility of nitrospiropyran, which was altered by modifying the structure of the background ligand, had a profound impact on the self-assembly process. By coating the nanoparticles with a spiropyran lacking the nitro group, a conceptually different self-assembly system, relying on a reversible proton transfer, was realized. The resulting particles spontaneously (in the dark) assembled into aggregates that could be readily disassembled upon exposure to blue light.}, author = {Kundu, Pintu K. and Das, Sanjib and Ahrens, Johannes and Klajn, Rafal}, issn = {2040-3372}, journal = {Nanoscale}, keywords = {General Materials Science}, number = {46}, pages = {19280--19286}, publisher = {Royal Society of Chemistry}, title = {{Controlling the lifetimes of dynamic nanoparticle aggregates by spiropyran functionalization}}, doi = {10.1039/c6nr05959g}, volume = {8}, year = {2016}, } @article{13386, abstract = {Azobenzenealkanethiols in self-assembled monolayers (SAMs) on Au(111) exhibit reversible trans–cis photoisomerization when diluted with alkanethiol spacers. Using these mixed SAMs, we show switching of the linear optical and second-harmonic response. The effective switching of these surface optical properties relies on a reasonably large cross section and a high photoisomerization yield as well as a long lifetime of the metastable cis isomer. We quantified the switching process by X-ray absorption spectroscopy. The cross sections for the trans–cis and cis–trans photoisomerization with 365 and 455 nm light, respectively, are 1 order of magnitude smaller than in solution. In vacuum, the 365 nm photostationary state comprises 50–74% of the molecules in the cis form, limited by their rapid thermal isomerization back to the trans state. In contrast, the 455 nm photostationary state contains nearly 100% trans-azobenzene. We determined time constants for the thermal cis–trans isomerization of only a few minutes in vacuum and in a dry nitrogen atmosphere but of more than 1 day in ambient air. Our results suggest that adventitious water adsorbed on the surface of the SAM stabilizes the polar cis configuration of azobenzene under ambient conditions. The back reaction rate constants differing by 2 orders of magnitude underline the huge influence of the environment and, accordingly, its importance when comparing various experiments.}, author = {Moldt, Thomas and Przyrembel, Daniel and Schulze, Michael and Bronsch, Wibke and Boie, Larissa and Brete, Daniel and Gahl, Cornelius and Klajn, Rafal and Tegeder, Petra and Weinelt, Martin}, issn = {1520-5827}, journal = {Langmuir}, keywords = {Electrochemistry, Spectroscopy, Surfaces and Interfaces, Condensed Matter Physics, General Materials Science}, number = {42}, pages = {10795--10801}, publisher = {American Chemical Society}, title = {{Differing isomerization kinetics of azobenzene-functionalized self-assembled monolayers in ambient air and in vacuum}}, doi = {10.1021/acs.langmuir.6b01690}, volume = {32}, year = {2016}, } @article{13387, abstract = {Come on in, the water's fine! Non-photoresponsive nanoparticles can be reversibly assembled using light by placing them in an aqueous solution of a photo­acid. Upon exposure to visible light, the photoacid reduces the pH of the solution, which induces attractive interactions between the nanoparticles. In the dark, the resulting nanoparticle aggregates spontaneously disassemble. The process can be repeated many times.}, author = {Samanta, Dipak and Klajn, Rafal}, issn = {2195-1071}, journal = {Advanced Optical Materials}, keywords = {Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}, number = {9}, pages = {1373--1377}, publisher = {Wiley}, title = {{Aqueous light-controlled self-assembly of nanoparticles}}, doi = {10.1002/adom.201600364}, volume = {4}, year = {2016}, } @misc{13388, abstract = {The Inside Cover picture illustrates the fluorescent properties of a gold nanocluster functionalized with several copies of a red-emitting merocyanine (image by Ella Marushchenko). The red fluorescence can be turned on and off reversibly by using an external stimulus.}, author = {Udayabhaskararao, T. and Kundu, Pintu K. and Ahrens, Johannes and Klajn, Rafal}, booktitle = {ChemPhysChem}, issn = {1439-7641}, keywords = {Physical and Theoretical Chemistry, Atomic and Molecular Physics, and Optics}, number = {12}, pages = {1711--1711}, publisher = {Wiley}, title = {{Inside cover: Reversible photoisomerization of spiropyran on the surfaces of Au25 nanoclusters (ChemPhysChem 12/2016)}}, doi = {10.1002/cphc.201600480}, volume = {17}, year = {2016}, } @article{13389, abstract = {Au25 nanoclusters functionalized with a spiropyran molecular switch are synthesized via a ligand-exchange reaction at low temperature. The resulting nanoclusters are characterized by optical and NMR spectroscopies as well as by mass spectrometry. Spiropyran bound to nanoclusters isomerizes in a reversible fashion when exposed to UV and visible light, and its properties are similar to those of free spiropyran molecules in solution. The reversible photoisomerization entails the modulation of fluorescence as well as the light-controlled self-assembly of nanoclusters.}, author = {Udayabhaskararao, T. and Kundu, Pintu K. and Ahrens, Johannes and Klajn, Rafal}, issn = {1439-7641}, journal = {ChemPhysChem}, keywords = {Physical and Theoretical Chemistry, Atomic and Molecular Physics, and Optics}, number = {12}, pages = {1805--1809}, publisher = {Wiley}, title = {{Reversible photoisomerization of spiropyran on the surfaces of Au25 nanoclusters}}, doi = {10.1002/cphc.201500897}, volume = {17}, year = {2016}, } @article{13390, author = {Klajn, Rafal}, issn = {1869-1870}, journal = {Science China Chemistry}, keywords = {General Chemistry}, number = {4}, pages = {420--421}, publisher = {Springer Nature}, title = {{Borrowing titania’s photoinduced electrons for molecular switching}}, doi = {10.1007/s11426-016-5573-4}, volume = {59}, year = {2016}, } @article{13391, abstract = {It is reported that spiropyran—a widely investigated molecular photoswitch—can be stabilized in aqueous environments in the presence of a variety of proteins, including human serum albumin, insulin fibrils, lysozyme, and glucose oxidase. The optical properties of the complexed photoswitch are protein dependent, with human serum albumin providing the spiropyran with emission features previously observed for a photoswitch confined in media of high viscosity. Despite being bound to the protein molecules, spiropyran can undergo a ring-opening reaction upon exposure to UV light. This photoisomerization process can affect the properties of the proteins: here, it is shown that the electrical conduction through human serum albumin to which the spiropyran is bound increases following the ring-opening reaction.}, author = {Amdursky, Nadav and Kundu, Pintu K. and Ahrens, Johannes and Huppert, Dan and Klajn, Rafal}, issn = {2192-6506}, journal = {ChemPlusChem}, keywords = {General Chemistry}, number = {1}, pages = {44--48}, publisher = {Wiley}, title = {{Noncovalent interactions with proteins modify the physicochemical properties of a molecular switch}}, doi = {10.1002/cplu.201500417}, volume = {81}, year = {2016}, } @inproceedings{1340, abstract = {We study repeated games with absorbing states, a type of two-player, zero-sum concurrent mean-payoff games with the prototypical example being the Big Match of Gillete (1957). These games may not allow optimal strategies but they always have ε-optimal strategies. In this paper we design ε-optimal strategies for Player 1 in these games that use only O(log log T) space. Furthermore, we construct strategies for Player 1 that use space s(T), for an arbitrary small unbounded non-decreasing function s, and which guarantee an ε-optimal value for Player 1 in the limit superior sense. The previously known strategies use space Ω(log T) and it was known that no strategy can use constant space if it is ε-optimal even in the limit superior sense. We also give a complementary lower bound. Furthermore, we also show that no Markov strategy, even extended with finite memory, can ensure value greater than 0 in the Big Match, answering a question posed by Neyman [11].}, author = {Hansen, Kristoffer and Ibsen-Jensen, Rasmus and Koucký, Michal}, location = {Liverpool, United Kingdom}, pages = {64 -- 76}, publisher = {Springer}, title = {{The big match in small space}}, doi = {10.1007/978-3-662-53354-3_6}, volume = {9928}, year = {2016}, } @inproceedings{1341, abstract = {In resource allocation games, selfish players share resources that are needed in order to fulfill their objectives. The cost of using a resource depends on the load on it. In the traditional setting, the players make their choices concurrently and in one-shot. That is, a strategy for a player is a subset of the resources. We introduce and study dynamic resource allocation games. In this setting, the game proceeds in phases. In each phase each player chooses one resource. A scheduler dictates the order in which the players proceed in a phase, possibly scheduling several players to proceed concurrently. The game ends when each player has collected a set of resources that fulfills his objective. The cost for each player then depends on this set as well as on the load on the resources in it – we consider both congestion and cost-sharing games. We argue that the dynamic setting is the suitable setting for many applications in practice. We study the stability of dynamic resource allocation games, where the appropriate notion of stability is that of subgame perfect equilibrium, study the inefficiency incurred due to selfish behavior, and also study problems that are particular to the dynamic setting, like constraints on the order in which resources can be chosen or the problem of finding a scheduler that achieves stability.}, author = {Avni, Guy and Henzinger, Thomas A and Kupferman, Orna}, location = {Liverpool, United Kingdom}, pages = {153 -- 166}, publisher = {Springer}, title = {{Dynamic resource allocation games}}, doi = {10.1007/978-3-662-53354-3_13}, volume = {9928}, year = {2016}, } @article{1342, abstract = {A key aspect of bacterial survival is the ability to evolve while migrating across spatially varying environmental challenges. Laboratory experiments, however, often study evolution in well-mixed systems. Here, we introduce an experimental device, the microbial evolution and growth arena (MEGA)-plate, in which bacteria spread and evolved on a large antibiotic landscape (120 × 60 centimeters) that allowed visual observation of mutation and selection in a migrating bacterial front.While resistance increased consistently, multiple coexisting lineages diversified both phenotypically and genotypically. Analyzing mutants at and behind the propagating front,we found that evolution is not always led by the most resistant mutants; highly resistant mutants may be trapped behindmore sensitive lineages.TheMEGA-plate provides a versatile platformfor studying microbial adaption and directly visualizing evolutionary dynamics.}, author = {Baym, Michael and Lieberman, Tami and Kelsic, Eric and Chait, Remy P and Gross, Rotem and Yelin, Idan and Kishony, Roy}, journal = {Science}, number = {6304}, pages = {1147 -- 1151}, publisher = {American Association for the Advancement of Science}, title = {{Spatiotemporal microbial evolution on antibiotic landscapes}}, doi = {10.1126/science.aag0822}, volume = {353}, year = {2016}, } @article{1343, abstract = {The Fermi-Hubbard model is one of the key models of condensed matter physics, which holds a potential for explaining the mystery of high-temperature superconductivity. Recent progress in ultracold atoms in optical lattices has paved the way to studying the model’s phase diagram using the tools of quantum simulation, which emerged as a promising alternative to the numerical calculations plagued by the infamous sign problem. However, the temperatures achieved using elaborate laser cooling protocols so far have been too high to show the appearance of antiferromagnetic (AF) and superconducting quantum phases directly. In this work, we demonstrate that using the machinery of dissipative quantum state engineering, one can observe the emergence of the AF order in the Fermi-Hubbard model with fermions in optical lattices. The core of the approach is to add incoherent laser scattering in such a way that the AF state emerges as the dark state of the driven-dissipative dynamics. The proposed controlled dissipation channels described in this work are straightforward to add to already existing experimental setups.}, author = {Kaczmarczyk, Jan and Weimer, Hendrik and Lemeshko, Mikhail}, journal = {New Journal of Physics}, number = {9}, publisher = {IOP Publishing}, title = {{Dissipative preparation of antiferromagnetic order in the Fermi-Hubbard model}}, doi = {10.1088/1367-2630/18/9/093042}, volume = {18}, year = {2016}, }