@article{533, abstract = {Any programming error that can be revealed before compiling a program saves precious time for the programmer. While integrated development environments already do a good job by detecting, e.g., data-flow abnormalities, current static analysis tools suffer from false positives ("noise") or require strong user interaction. We propose to avoid this deficiency by defining a new class of errors. A program fragment is doomed if its execution will inevitably fail, regardless of which state it is started in. We use a formal verification method to identify such errors fully automatically and, most significantly, without producing noise. We report on experiments with a prototype tool.}, author = {Hoenicke, Jochen and Leino, Kari and Podelski, Andreas and Schäf, Martin and Wies, Thomas}, journal = {Formal Methods in System Design}, number = {2-3}, pages = {171 -- 199}, publisher = {Springer}, title = {{Doomed program points}}, doi = {10.1007/s10703-010-0102-0}, volume = {37}, year = {2010}, } @misc{5388, abstract = {We present an algorithmic method for the synthesis of concurrent programs that are optimal with respect to quantitative performance measures. The input consists of a sequential sketch, that is, a program that does not contain synchronization constructs, and of a parametric performance model that assigns costs to actions such as locking, context switching, and idling. The quantitative synthesis problem is to automatically introduce synchronization constructs into the sequential sketch so that both correctness is guaranteed and worst-case (or average-case) performance is optimized. Correctness is formalized as race freedom or linearizability. We show that for worst-case performance, the problem can be modeled as a 2-player graph game with quantitative (limit-average) objectives, and for average-case performance, as a 2 1/2 -player graph game (with probabilistic transitions). In both cases, the optimal correct program is derived from an optimal strategy in the corresponding quantitative game. We prove that the respective game problems are computationally expensive (NP-complete), and present several techniques that overcome the theoretical difficulty in cases of concurrent programs of practical interest. We have implemented a prototype tool and used it for the automatic syn- thesis of programs that access a concurrent list. For certain parameter val- ues, our method automatically synthesizes various classical synchronization schemes for implementing a concurrent list, such as fine-grained locking or a lazy algorithm. For other parameter values, a new, hybrid synchronization style is synthesized, which uses both the lazy approach and coarse-grained locks (instead of standard fine-grained locks). The trade-off occurs because while fine-grained locking tends to decrease the cost that is due to waiting for locks, it increases cache size requirements.}, author = {Chatterjee, Krishnendu and Cerny, Pavol and Henzinger, Thomas A and Radhakrishna, Arjun and Singh, Rohit}, issn = {2664-1690}, pages = {17}, publisher = {IST Austria}, title = {{Quantitative synthesis for concurrent programs}}, doi = {10.15479/AT:IST-2010-0004}, year = {2010}, } @misc{5389, abstract = {Boolean notions of correctness are formalized by preorders on systems. Quantitative measures of correctness can be formalized by real-valued distance functions between systems, where the distance between implementation and specification provides a measure of “fit” or “desirability.” We extend the simulation preorder to the quantitative setting, by making each player of a simulation game pay a certain price for her choices. We use the resulting games with quantitative objectives to define three different simulation distances. The correctness distance measures how much the specification must be changed in order to be satisfied by the implementation. The coverage distance measures how much the im- plementation restricts the degrees of freedom offered by the specification. The robustness distance measures how much a system can deviate from the implementation description without violating the specification. We consider these distances for safety as well as liveness specifications. The distances can be computed in polynomial time for safety specifications, and for liveness specifications given by weak fairness constraints. We show that the distance functions satisfy the triangle inequality, that the distance between two systems does not increase under parallel composition with a third system, and that the distance between two systems can be bounded from above and below by distances between abstractions of the two systems. These properties suggest that our simulation distances provide an appropriate basis for a quantitative theory of discrete systems. We also demonstrate how the robustness distance can be used to measure how many transmission errors are tolerated by error correcting codes.}, author = {Cerny, Pavol and Henzinger, Thomas A and Radhakrishna, Arjun}, issn = {2664-1690}, pages = {24}, publisher = {IST Austria}, title = {{Simulation distances}}, doi = {10.15479/AT:IST-2010-0003}, year = {2010}, } @misc{5390, abstract = {The class of ω regular languages provide a robust specification language in verification. Every ω-regular condition can be decomposed into a safety part and a liveness part. The liveness part ensures that something good happens “eventually.” Two main strengths of the classical, infinite-limit formulation of liveness are robustness (independence from the granularity of transitions) and simplicity (abstraction of complicated time bounds). However, the classical liveness formulation suffers from the drawback that the time until something good happens may be unbounded. A stronger formulation of liveness, so-called finitary liveness, overcomes this drawback, while still retaining robustness and simplicity. Finitary liveness requires that there exists an unknown, fixed bound b such that something good happens within b transitions. In this work we consider the finitary parity and Streett (fairness) conditions. We present the topological, automata-theoretic and logical characterization of finitary languages defined by finitary parity and Streett conditions. We (a) show that the finitary parity and Streett languages are Σ2-complete; (b) present a complete characterization of the expressive power of various classes of automata with finitary and infinitary conditions (in particular we show that non-deterministic finitary parity and Streett automata cannot be determinized to deterministic finitary parity or Streett automata); and (c) show that the languages defined by non-deterministic finitary parity automata exactly characterize the star-free fragment of ωB-regular languages.}, author = {Chatterjee, Krishnendu and Fijalkow, Nathanaël}, issn = {2664-1690}, pages = {21}, publisher = {IST Austria}, title = {{Topological, automata-theoretic and logical characterization of finitary languages}}, doi = {10.15479/AT:IST-2010-0002}, year = {2010}, } @misc{5391, abstract = {Concurrent data structures with fine-grained synchronization are notoriously difficult to implement correctly. The difficulty of reasoning about these implementations does not stem from the number of variables or the program size, but rather from the large number of possible interleavings. These implementations are therefore prime candidates for model checking. We introduce an algorithm for verifying linearizability of singly-linked heap-based concurrent data structures. We consider a model consisting of an unbounded heap where each node consists an element from an unbounded data domain, with a restricted set of operations for testing and updating pointers and data elements. Our main result is that linearizability is decidable for programs that invoke a fixed number of methods, possibly in parallel. This decidable fragment covers many of the common implementation techniques — fine-grained locking, lazy synchronization, and lock-free synchronization. We also show how the technique can be used to verify optimistic implementations with the help of programmer annotations. We developed a verification tool CoLT and evaluated it on a representative sample of Java implementations of the concurrent set data structure. The tool verified linearizability of a number of implementations, found a known error in a lock-free imple- mentation and proved that the corrected version is linearizable.}, author = {Cerny, Pavol and Radhakrishna, Arjun and Zufferey, Damien and Chaudhuri, Swarat and Alur, Rajeev}, issn = {2664-1690}, pages = {27}, publisher = {IST Austria}, title = {{Model checking of linearizability of concurrent list implementations}}, doi = {10.15479/AT:IST-2010-0001}, year = {2010}, } @inbook{5940, author = {Juhás, Gabriel and Kazlov, Igor and Juhásová, Ana}, booktitle = {Applications and Theory of Petri Nets}, isbn = {9783642136740}, issn = {0302-9743}, pages = {1--17}, publisher = {Springer Berlin Heidelberg}, title = {{Instance Deadlock: A Mystery behind Frozen Programs}}, doi = {10.1007/978-3-642-13675-7_1}, year = {2010}, } @article{598, abstract = {It is not well understood how the human Mediator complex, transcription factor IIH and RNA polymerase II (Pol II) work together with activators to initiate transcription. Activator binding alters Mediator structure, yet the functional consequences of such structural shifts remain unknown. The p53 C terminus and its activation domain interact with different Mediator subunits, and we find that each interaction differentially affects Mediator structure; strikingly, distinct p53-Mediator structures differentially affect Pol II activity. Only the p53 activation domain induces the formation of a large pocket domain at the Mediator-Pol II interaction site, and this correlates with activation of stalled Pol II to a productively elongating state. Moreover, we define a Mediator requirement for TFIIH-dependent Pol II C-terminal domain phosphorylation and identify substantial differences in Pol II C-terminal domain processing that correspond to distinct p53-Mediator structural states. Our results define a fundamental mechanism by which p53 activates transcription and suggest that Mediator structural shifts trigger activation of stalled Pol II complexes.}, author = {Meyer, Krista and Lin, Shih and Bernecky, Carrie A and Gao, Yuefeng and Taatjes, Dylan}, journal = {Nature Structural and Molecular Biology}, number = {6}, pages = {753 -- 760}, publisher = {Nature Publishing Group}, title = {{P53 activates transcription by directing structural shifts in Mediator}}, doi = {10.1038/nsmb.1816}, volume = {17}, year = {2010}, } @article{6142, abstract = {Defining the mutational landscape when individuals of a species grow separately and diverge over many generations can provide insights into trait evolution. A specific example of this involves studying changes associated with domestication where different lines of the same wild stock have been cultivated independently in different standard environments. Whole genome sequence comparison of such lines permits estimation of mutation rates, inference of genes' ancestral states and ancestry of existing strains, and correction of sequencing errors in genome databases. Here we study domestication of the C. elegans Bristol strain as a model, and report the genome sequence of LSJ1 (Bristol), a sibling of the standard C. elegans reference wild type N2 (Bristol). The LSJ1 and N2 lines were cultivated separately from shortly after the Bristol strain was isolated until methods to freeze C. elegans were developed. We find that during this time the two strains have accumulated 1208 genetic differences. We describe phenotypic variation between N2 and LSJ1 in the rate at which embryos develop, the rate of production of eggs, the maturity of eggs at laying, and feeding behavior, all the result of post-isolation changes. We infer the ancestral alleles in the original Bristol isolate and highlight 2038 likely sequencing errors in the original N2 reference genome sequence. Many of these changes modify genome annotation. Our study provides a starting point to further investigate genotype-phenotype association and offers insights into the process of selection as a result of laboratory domestication.}, author = {Weber, Katherine P. and De, Subhajyoti and Kozarewa, Iwanka and Turner, Daniel J. and Babu, M. Madan and de Bono, Mario}, issn = {1932-6203}, journal = {PLoS ONE}, number = {11}, publisher = {Public Library of Science}, title = {{Whole genome sequencing highlights genetic changes associated with laboratory domestication of C. elegans}}, doi = {10.1371/journal.pone.0013922}, volume = {5}, year = {2010}, } @inbook{619, abstract = {Sinclair Ross’s novel As for Me and My House has long since been canonized as Canadian prairie fiction. Accordingly, it has been the subject of many critical studies and academic papers. Most commentators have concentrated on such literary issues as the representation of the western landscape or the reliability of the female narrator. But so far little consideration has been given to the social and cultural implications of the novel. Few attempts have been made to analyze the text from a cultural perspective including such social markers as class, gender and ethnicity. That is all the more surprising because Sinclair Ross has often been credited for being a realistic author and As for Me and My House has often been interpreted as a regional novel characteristic of a particular time and place.}, author = {Zacharasiewicz, Waldemar and Kirsch, Fritz Peter}, booktitle = {Social and cultural interaction and literary landscapes in the Canadian West : impressions of an exploratory field trip and academic interaction in the Canadian West : Rapports interculturels et paysages littéraires dans l'Ouest canadien}, pages = {173 -- 179}, publisher = {Facultas.WUV}, title = {{“This is a fundamentalist town”: The Prairie Town as a Site of Social and Cultural Conflict in Sinclair Ross’s As for Me and My House}}, year = {2010}, } @article{6198, abstract = {Stroke is a major public health problem leading to high rates of death and disability in adults. Excessive stimulation of N-methyl-D-aspartate receptors (NMDARs) and the resulting neuronal nitric oxide synthase (nNOS) activation are crucial for neuronal injury after stroke insult. However, directly inhibiting NMDARs or nNOS can cause severe side effects because they have key physiological functions in the CNS. Here we show that cerebral ischemia induces the interaction of nNOS with postsynaptic density protein-95 (PSD-95). Disrupting nNOS-PSD-95 interaction via overexpressing the N-terminal amino acid residues 1-133 of nNOS (nNOS-N(1-133)) prevented glutamate-induced excitotoxicity and cerebral ischemic damage. Given the mechanism of nNOS-PSD-95 interaction, we developed a series of compounds and discovered a small-molecular inhibitor of the nNOS-PSD-95 interaction, ZL006. This drug blocked the ischemia-induced nNOS-PSD-95 association selectively, had potent neuroprotective activity in vitro and ameliorated focal cerebral ischemic damage in mice and rats subjected to middle cerebral artery occlusion (MCAO) and reperfusion. Moreover, it readily crossed the blood-brain barrier, did not inhibit NMDAR function, catalytic activity of nNOS or spatial memory, and had no effect on aggressive behaviors. Thus, this new drug may serve as a treatment for stroke, perhaps without major side effects. }, author = {Zhou, L and Li, F and Xu, Haibing and Luo, CX and Wu, HY and Zhu, MM and Lu, W and Ji, X and Zhou, QG and Zhu, DY}, issn = {1078-8956}, journal = {Nature Medicine}, number = {12}, pages = {1439--1443}, publisher = {Nature Publishing Group}, title = {{Treatment of cerebral ischemia by disrupting ischemia-induced interaction of nNOS with PSD-95}}, doi = {10.1038/nm.2245}, volume = {16}, year = {2010}, } @article{7078, abstract = {We report resonant ultrasound spectroscopy (RUS), dilatometry/magnetostriction, magnetotransport, magnetization, specific-heat, and 119Sn Mössbauer spectroscopy measurements on SnTe and Sn0.995Cr0.005Te. Hall measurements at T=77 K indicate that our Bridgman-grown single crystals have a p-type carrier concentration of 3.4×1019 cm−3 and that our Cr-doped crystals have an n-type concentration of 5.8×1022 cm−3. Although our SnTe crystals are diamagnetic over the temperature range 2≤T≤1100 K, the Cr-doped crystals are room-temperature ferromagnets with a Curie temperature of 294 K. For each sample type, three-terminal capacitive dilatometry measurements detect a subtle 0.5 μm distortion at Tc≈85 K. Whereas our RUS measurements on SnTe show elastic hardening near the structural transition, pointing to co-elastic behavior, similar measurements on Sn0.995Cr0.005Te show a pronounced softening, pointing to ferroelastic behavior. Effective Debye temperature, θD, values of SnTe obtained from 119Sn Mössbauer studies show a hardening of phonons in the range 60–115 K (θD=162 K) as compared with the 100–300 K range (θD=150 K). In addition, a precursor softening extending over approximately 100 K anticipates this collapse at the critical temperature and quantitative analysis over three decades of its reduced modulus finds ΔC44/C44=A|(T−T0)/T0|−κ with κ=0.50±0.02, a value indicating a three-dimensional softening of phonon branches at a temperature T0∼75 K, considerably below Tc. We suggest that the differences in these two types of elastic behaviors lie in the absence of elastic domain-wall motion in the one case and their nucleation in the other.}, author = {Salje, E. K. H. and Safarik, D. J. and Modic, Kimberly A and Gubernatis, J. E. and Cooley, J. C. and Taylor, R. D. and Mihaila, B. and Saxena, A. and Lookman, T. and Smith, J. L. and Fisher, R. A. and Pasternak, M. and Opeil, C. P. and Siegrist, T. and Littlewood, P. B. and Lashley, J. C.}, issn = {1098-0121}, journal = {Physical Review B}, number = {18}, publisher = {APS}, title = {{Tin telluride: A weakly co-elastic metal}}, doi = {10.1103/physrevb.82.184112}, volume = {82}, year = {2010}, } @article{7079, abstract = {We have observed that reacting Pb:Te:Ag:Se in a 1:1:1.9:1 molar ratio gives rise to what appears to be a predominantly single-phase alloy, which crystallizes in the PbSe cF8 fcc structure. However, further investigation of the structure using energy dispersive x-ray analysis reveals the presence of two phases, PbSe and β-Ag2Te, with identical lattice parameters. The total thermal conductivity of the formed alloy is remarkably low for a crystalline material, κT<0.6W∕mK at 675K, it is reproducible, and in addition, the compound has good mechanical properties.}, author = {Drymiotis, Fivos R. and Drye, Tyler B. and Wang, Yisha and He, Jian and Rhodes, Daniel and Modic, Kimberly A and Cawthorne, Samantha and Zhang, Qiu Run}, issn = {0021-8979}, journal = {Journal of Applied Physics}, number = {3}, publisher = {AIP}, title = {{Structure formation and very low thermal conductivity in Pb:Te:Ag:Se mixtures}}, doi = {10.1063/1.3284946}, volume = {107}, year = {2010}, } @article{7318, abstract = {The decomposition reaction of H2O2 aqueous solutions (H2O2 - H2O + 1/2O2) catalyzed by transition metal oxide powders has been compared with the charging voltage of nonaqueous Li-O2 cells containing the same catalyst. An inverse linear relationship between Ln k (rate constant for the H2O2 decomposition) and the charging voltage has been found, despite differences in media and possible mechanistic differences. The results suggest that the decomposition may be a reliable, useful, and fast screening tool for materials that promote the charging process of the Li-O2 battery and may ultimately give insight into the charging mechanism.}, author = {Giordani, V. and Freunberger, Stefan Alexander and Bruce, P. G. and Tarascon, J.-M. and Larcher, D.}, issn = {1099-0062}, journal = {Electrochemical and Solid-State Letters}, number = {12}, publisher = {The Electrochemical Society}, title = {{H2O2 decomposition reaction as selecting tool for catalysts in Li–O2 cells}}, doi = {10.1149/1.3494045}, volume = {13}, year = {2010}, } @inproceedings{754, abstract = {Most people believe that renaming is easy: simply choose a name at random; if more than one process selects the same name, then try again. We highlight the issues that occur when trying to implement such a scheme and shed new light on the read-write complexity of randomized renaming in an asynchronous environment. At the heart of our new perspective stands an adaptive implementation of a randomized test-and-set object, that has poly-logarithmic step complexity per operation, with high probability. Interestingly, our implementation is anonymous, as it does not require process identifiers. Based on this implementation, we present two new randomized renaming algorithms. The first ensures a tight namespace of n names using O( n log4 n) total steps, with high probability. This significantly improves on the complexity of the best previously known namespace-optimal algorithms. The second algorithm achieves a namespace of size k (1 + ε) using O( k log4 k / log2 (1 + ε) ) total steps, both with high probability, where k is the total contention in the execution. It is the first adaptive randomized renaming algorithm, and it improves on existing deterministic solutions by providing a smaller namespace, and by lowering step complexity.}, author = {Alistarh, Dan-Adrian and Attiya, Hagit and Gilbert, Seth and Giurgiu, Andrei and Guerraoui, Rachid}, pages = {94 -- 108}, publisher = {Springer}, title = {{Fast randomized test-and-set and renaming}}, doi = {10.1007/978-3-642-15763-9_9}, volume = {6343 LNCS}, year = {2010}, } @inproceedings{755, abstract = {Gossip, also known as epidemic dissemination, is becoming an increasingly popular technique in distributed systems. Yet, it has remained a partially open question: how robust are such protocols? We consider a natural extension of the random phone-call model (introduced by Karp et al. [1]), and we analyze two different notions of robustness: the ability to tolerate adaptive failures, and the ability to tolerate oblivious failures. For adaptive failures, we present a new gossip protocol, TrickleGossip, which achieves near-optimal O(n log 3 n) message complexity. To the best of our knowledge, this is the first epidemic-style protocol that can tolerate adaptive failures. We also show a direct relation between resilience and message complexity, demonstrating that gossip protocols which tolerate a large number of adaptive failures need to use a super-linear number of messages with high probability. For oblivious failures, we present a new gossip protocol, CoordinatedGossip, that achieves optimal O(n) message complexity. This protocol makes novel use of the universe reduction technique to limit the message complexity.}, author = {Alistarh, Dan-Adrian and Gilbert, Seth and Guerraoui, Rachid and Zadimoghaddam, Morteza}, number = {PART 2}, pages = {115 -- 126}, publisher = {Springer}, title = {{How efficient can gossip be? (On the cost of resilient information exchange)}}, doi = {10.1007/978-3-642-14162-1_10}, volume = {6199 LNCS}, year = {2010}, } @inproceedings{756, abstract = {This paper studies non-cryptographic authenticated broadcast in radio networks subject to malicious failures. We introduce two protocols that address this problem. The first, NeighborWatchRB, makes use of a novel strategy in which honest devices monitor their neighbors for malicious behavior. Second, we present a more robust variant, MultiPathRB, that tolerates the maximum possible density of malicious devices per region, using an elaborate voting strategy. We also introduce a new proof technique to show that both protocols ensure asymptotically optimal running time. We demonstrate the fault tolerance of our protocols through extensive simulation. Simulations show the practical superiority of the NeighborWatchRB protocol (an advantage hidden in the constants of the asymptotic complexity). The NeighborWatchRB protocol even performs relatively well when compared to the simple, fast epidemic protocols commonly used in the radio setting, protocols that tolerate no malicious faults. We therefore believe that the overhead for ensuring authenticated broadcast is reasonable, especially in applications that use authenticated broadcast only when necessary, such as distributing an authenticated digest.}, author = {Alistarh, Dan-Adrian and Gilbert, Seth and Guerraoui, Rachid and Milošević, Žarko and Newport, Calvin}, pages = {50 -- 59}, publisher = {ACM}, title = {{Securing every bit: Authenticated broadcast in radio networks}}, doi = {10.1145/1810479.1810489}, year = {2010}, } @inproceedings{758, abstract = {Set agreement [4] is a fundamental problem in distributed computing, in which processes collectively choose a small subset of values from a larger set of proposals. Set agreement has been extensively studied in both synchronous and asynchronous systems [10,11,3,5,8,9]. Real world distributed systems, however, are neither purely synchronous nor purely asynchronous. To describe such a system, Dwork et al. [6] introduced the idea of partial synchrony. They assume for every execution some (unknown) time GST (global stabilization time), after which the system is synchronous. In a recent paper [1,2], we study the complexity of set agreement in the context of partially synchronous systems, determining the minimum-sized window of synchrony in which set agreement can be solved. We show that at least ⌊t/k⌋ + 2 synchronous rounds are required for k-set agreement, where t < n is the number of crashes, and k is the agreement parameter of the set agreement task. We then introduce an algorithm that terminates in any window of synchrony of size at least ⌊t/k⌋ + 4 rounds. Together, these results tightly bound the inherent price of tolerating some asynchrony.}, author = {Alistarh, Dan-Adrian and Gilbert, Seth and Guerraoui, Rachid and Travers, Corentin}, pages = {404 -- 405}, publisher = {Springer}, title = {{Brief announcement: New bounds for partially synchronous set agreement}}, doi = {10.1007/978-3-642-15763-9_40}, volume = {6343 LNCS}, year = {2010}, } @inproceedings{3430, abstract = {These are notes for a set of 7 two-hour lectures given at the 2010 Summer School on Quantitative Evolutionary and Comparative Genomics at OIST, Okinawa, Japan. The emphasis is on understanding how biological systems process information. We take a physicist's approach of looking for simple phenomenological descriptions that can address the questions of biological function without necessarily modeling all (mostly unknown) microscopic details; the example that is developed throughout the notes is transcriptional regulation in genetic regulatory networks. We present tools from information theory and statistical physics that can be used to analyze noisy nonlinear biological networks, and build generative and predictive models of regulatory processes.}, author = {Gasper Tkacik}, publisher = {Elsevier}, title = {{Lecture notes for 2010 summer school on Quantitative Evolutionary and Comparative Genomics}}, year = {2010}, } @article{3441, abstract = {The hippocampus is an important brain circuit for spatial memory and the spatially selective spiking of hippocampal neuronal assemblies is thought to provide a mnemonic representation of space. We found that remembering newly learnt goal locations required NMDA receptorĝ€"dependent stabilization and enhanced reactivation of goal-related hippocampal assemblies. During spatial learning, place-related firing patterns in the CA1, but not CA3, region of the rat hippocampus were reorganized to represent new goal locations. Such reorganization did not occur when goals were marked by visual cues. The stabilization and successful retrieval of these newly acquired CA1 representations of behaviorally relevant places was NMDAR dependent and necessary for subsequent memory retention performance. Goal-related assembly patterns associated with sharp wave/ripple network oscillations, during both learning and subsequent rest periods, predicted memory performance. Together, these results suggest that the reorganization and reactivation of assembly firing patterns in the hippocampus represent the formation and expression of new spatial memory traces. © 2010 Nature America, Inc. All rights reserved.}, author = {Dupret, David and Joseph O'Neill and Pleydell-Bouverie, Barty and Jozsef Csicsvari}, journal = {Nature Neuroscience}, number = {8}, pages = {995 -- 1002}, publisher = {Nature Publishing Group}, title = {{The reorganization and reactivation of hippocampal maps predict spatial memory performance}}, doi = {10.1038/nn.2599}, volume = {13}, year = {2010}, } @article{3442, abstract = {Episodic and spatial memories each involve the encoding of complex associations in hippocampal neuronal circuits. Such memory traces could be stabilised from short- to long-term forms by consolidation processes involving the 'reactivation' of the original network firing patterns during sleep and rest. Waking experience can be replayed in many different brain areas, but an important role for the hippocampus lies in the organisation of the 'reactivation' process. Emerging evidence suggests that sharp wave/ripple (SWR) events in the hippocampus could coordinate the reactivation of memory traces and direct their reinstatement in cortical circuits. Although the mechanisms remain uncertain, there is a growing consensus that such SWR-directed reactivation of brain-wide memory traces could underlie memory consolidation. © 2010 Elsevier Ltd.}, author = {Joseph O'Neill and Pleydell-Bouverie, Barty and Dupret, David and Jozsef Csicsvari}, journal = {Trends in Neurosciences}, number = {5}, pages = {220 -- 229}, publisher = {Elsevier}, title = {{Play it again: reactivation of waking experience and memory}}, doi = {10.1016/j.tins.2010.01.006}, volume = {33}, year = {2010}, }