@article{2180,
abstract = {Weighted majority votes allow one to combine the output of several classifiers or voters. MinCq is a recent algorithm for optimizing the weight of each voter based on the minimization of a theoretical bound over the risk of the vote with elegant PAC-Bayesian generalization guarantees. However, while it has demonstrated good performance when combining weak classifiers, MinCq cannot make use of the useful a priori knowledge that one may have when using a mixture of weak and strong voters. In this paper, we propose P-MinCq, an extension of MinCq that can incorporate such knowledge in the form of a constraint over the distribution of the weights, along with general proofs of convergence that stand in the sample compression setting for data-dependent voters. The approach is applied to a vote of k-NN classifiers with a specific modeling of the voters' performance. P-MinCq significantly outperforms the classic k-NN classifier, a symmetric NN and MinCq using the same voters. We show that it is also competitive with LMNN, a popular metric learning algorithm, and that combining both approaches further reduces the error.},
author = {Bellet, Aurélien and Habrard, Amaury and Morvant, Emilie and Sebban, Marc},
journal = {Machine Learning},
number = {1-2},
pages = {129 -- 154},
publisher = {Springer},
title = {{Learning a priori constrained weighted majority votes}},
doi = {10.1007/s10994-014-5462-z},
volume = {97},
year = {2014},
}
@article{2183,
abstract = {We describe a simple adaptive network of coupled chaotic maps. The network reaches a stationary state (frozen topology) for all values of the coupling parameter, although the dynamics of the maps at the nodes of the network can be nontrivial. The structure of the network shows interesting hierarchical properties and in certain parameter regions the dynamics is polysynchronous: Nodes can be divided in differently synchronized classes but, contrary to cluster synchronization, nodes in the same class need not be connected to each other. These complicated synchrony patterns have been conjectured to play roles in systems biology and circuits. The adaptive system we study describes ways whereby this behavior can evolve from undifferentiated nodes.},
author = {Botella Soler, Vicente and Glendinning, Paul},
journal = {Physical Review E Statistical Nonlinear and Soft Matter Physics},
number = {6},
publisher = {American Institute of Physics},
title = {{Hierarchy and polysynchrony in an adaptive network }},
doi = {10.1103/PhysRevE.89.062809},
volume = {89},
year = {2014},
}
@article{2184,
abstract = {Given topological spaces X,Y, a fundamental problem of algebraic topology is understanding the structure of all continuous maps X→ Y. We consider a computational version, where X,Y are given as finite simplicial complexes, and the goal is to compute [X,Y], that is, all homotopy classes of suchmaps.We solve this problem in the stable range, where for some d ≥ 2, we have dim X ≤ 2d-2 and Y is (d-1)-connected; in particular, Y can be the d-dimensional sphere Sd. The algorithm combines classical tools and ideas from homotopy theory (obstruction theory, Postnikov systems, and simplicial sets) with algorithmic tools from effective algebraic topology (locally effective simplicial sets and objects with effective homology). In contrast, [X,Y] is known to be uncomputable for general X,Y, since for X = S1 it includes a well known undecidable problem: testing triviality of the fundamental group of Y. In follow-up papers, the algorithm is shown to run in polynomial time for d fixed, and extended to other problems, such as the extension problem, where we are given a subspace A ⊂ X and a map A→ Y and ask whether it extends to a map X → Y, or computing the Z2-index-everything in the stable range. Outside the stable range, the extension problem is undecidable.},
author = {Čadek, Martin and Krcál, Marek and Matoušek, Jiří and Sergeraert, Francis and Vokřínek, Lukáš and Wagner, Uli},
journal = {Journal of the ACM},
number = {3},
publisher = {ACM},
title = {{Computing all maps into a sphere}},
doi = {10.1145/2597629},
volume = {61},
year = {2014},
}
@inproceedings{2185,
abstract = {We revisit the classical problem of converting an imperfect source of randomness into a usable cryptographic key. Assume that we have some cryptographic application P that expects a uniformly random m-bit key R and ensures that the best attack (in some complexity class) against P(R) has success probability at most δ. Our goal is to design a key-derivation function (KDF) h that converts any random source X of min-entropy k into a sufficiently "good" key h(X), guaranteeing that P(h(X)) has comparable security δ′ which is 'close' to δ. Seeded randomness extractors provide a generic way to solve this problem for all applications P, with resulting security δ′ = O(δ), provided that we start with entropy k ≥ m + 2 log (1/δ) - O(1). By a result of Radhakrishnan and Ta-Shma, this bound on k (called the "RT-bound") is also known to be tight in general. Unfortunately, in many situations the loss of 2 log (1/δ) bits of entropy is unacceptable. This motivates the study KDFs with less entropy waste by placing some restrictions on the source X or the application P. In this work we obtain the following new positive and negative results in this regard: - Efficient samplability of the source X does not help beat the RT-bound for general applications. This resolves the SRT (samplable RT) conjecture of Dachman-Soled et al. [DGKM12] in the affirmative, and also shows that the existence of computationally-secure extractors beating the RT-bound implies the existence of one-way functions. - We continue in the line of work initiated by Barak et al. [BDK+11] and construct new information-theoretic KDFs which beat the RT-bound for large but restricted classes of applications. Specifically, we design efficient KDFs that work for all unpredictability applications P (e.g., signatures, MACs, one-way functions, etc.) and can either: (1) extract all of the entropy k = m with a very modest security loss δ′ = O(δ·log (1/δ)), or alternatively, (2) achieve essentially optimal security δ′ = O(δ) with a very modest entropy loss k ≥ m + loglog (1/δ). In comparison, the best prior results from [BDK+11] for this class of applications would only guarantee δ′ = O(√δ) when k = m, and would need k ≥ m + log (1/δ) to get δ′ = O(δ). - The weaker bounds of [BDK+11] hold for a larger class of so-called "square- friendly" applications (which includes all unpredictability, but also some important indistinguishability, applications). Unfortunately, we show that these weaker bounds are tight for the larger class of applications. - We abstract out a clean, information-theoretic notion of (k,δ,δ′)- unpredictability extractors, which guarantee "induced" security δ′ for any δ-secure unpredictability application P, and characterize the parameters achievable for such unpredictability extractors. Of independent interest, we also relate this notion to the previously-known notion of (min-entropy) condensers, and improve the state-of-the-art parameters for such condensers.},
author = {Dodis, Yevgeniy and Pietrzak, Krzysztof Z and Wichs, Daniel},
editor = {Nguyen, Phong and Oswald, Elisabeth},
location = {Copenhagen, Denmark},
pages = {93 -- 110},
publisher = {Springer},
title = {{Key derivation without entropy waste}},
doi = {10.1007/978-3-642-55220-5_6},
volume = {8441},
year = {2014},
}
@article{2186,
abstract = {We prove the existence of scattering states for the defocusing cubic Gross-Pitaevskii (GP) hierarchy in ℝ3. Moreover, we show that an exponential energy growth condition commonly used in the well-posedness theory of the GP hierarchy is, in a specific sense, necessary. In fact, we prove that without the latter, there exist initial data for the focusing cubic GP hierarchy for which instantaneous blowup occurs.},
author = {Chen, Thomas and Hainzl, Christian and Pavlović, Nataša and Seiringer, Robert},
journal = {Letters in Mathematical Physics},
number = {7},
pages = {871 -- 891},
publisher = {Springer},
title = {{On the well-posedness and scattering for the Gross-Pitaevskii hierarchy via quantum de Finetti}},
doi = {10.1007/s11005-014-0693-2},
volume = {104},
year = {2014},
}
@article{2187,
abstract = {Systems should not only be correct but also robust in the sense that they behave reasonably in unexpected situations. This article addresses synthesis of robust reactive systems from temporal specifications. Existing methods allow arbitrary behavior if assumptions in the specification are violated. To overcome this, we define two robustness notions, combine them, and show how to enforce them in synthesis. The first notion applies to safety properties: If safety assumptions are violated temporarily, we require that the system recovers to normal operation with as few errors as possible. The second notion requires that, if liveness assumptions are violated, as many guarantees as possible should be fulfilled nevertheless. We present a synthesis procedure achieving this for the important class of GR(1) specifications, and establish complexity bounds. We also present an implementation of a special case of robustness, and show experimental results.},
author = {Bloem, Roderick and Chatterjee, Krishnendu and Greimel, Karin and Henzinger, Thomas A and Hofferek, Georg and Jobstmann, Barbara and Könighofer, Bettina and Könighofer, Robert},
journal = {Acta Informatica},
number = {3-4},
pages = {193 -- 220},
publisher = {Springer},
title = {{Synthesizing robust systems}},
doi = {10.1007/s00236-013-0191-5},
volume = {51},
year = {2014},
}
@article{2188,
abstract = {Although plant and animal cells use a similar core mechanism to deliver proteins to the plasma membrane, their different lifestyle, body organization and specific cell structures resulted in the acquisition of regulatory mechanisms that vary in the two kingdoms. In particular, cell polarity regulators do not seem to be conserved, because genes encoding key components are absent in plant genomes. In plants, the broad knowledge on polarity derives from the study of auxin transporters, the PIN-FORMED proteins, in the model plant Arabidopsis thaliana. In animals, much information is provided from the study of polarity in epithelial cells that exhibit basolateral and luminal apical polarities, separated by tight junctions. In this review, we summarize the similarities and differences of the polarization mechanisms between plants and animals and survey the main genetic approaches that have been used to characterize new genes involved in polarity establishment in plants, including the frequently used forward and reverse genetics screens as well as a novel chemical genetics approach that is expected to overcome the limitation of classical genetics methods.},
author = {Kania, Urszula and Fendrych, Matyas and Friml, Jiřĺ},
journal = {Open Biology},
number = {APRIL},
publisher = {Royal Society},
title = {{Polar delivery in plants; commonalities and differences to animal epithelial cells}},
doi = {10.1098/rsob.140017},
volume = {4},
year = {2014},
}
@inproceedings{2189,
abstract = {En apprentissage automatique, nous parlons d'adaptation de domaine lorsque les données de test (cibles) et d'apprentissage (sources) sont générées selon différentes distributions. Nous devons donc développer des algorithmes de classification capables de s'adapter à une nouvelle distribution, pour laquelle aucune information sur les étiquettes n'est disponible. Nous attaquons cette problématique sous l'angle de l'approche PAC-Bayésienne qui se focalise sur l'apprentissage de modèles définis comme des votes de majorité sur un ensemble de fonctions. Dans ce contexte, nous introduisons PV-MinCq une version adaptative de l'algorithme (non adaptatif) MinCq. PV-MinCq suit le principe suivant. Nous transférons les étiquettes sources aux points cibles proches pour ensuite appliquer MinCq sur l'échantillon cible ``auto-étiqueté'' (justifié par une borne théorique). Plus précisément, nous définissons un auto-étiquetage non itératif qui se focalise dans les régions où les distributions marginales source et cible sont les plus similaires. Dans un second temps, nous étudions l'influence de notre auto-étiquetage pour en déduire une procédure de validation des hyperparamètres. Finalement, notre approche montre des résultats empiriques prometteurs.},
author = {Morvant, Emilie},
location = {Saint-Etienne, France},
pages = {49--58},
publisher = {Elsevier},
title = {{Adaptation de domaine de vote de majorité par auto-étiquetage non itératif}},
volume = {1},
year = {2014},
}
@inproceedings{2190,
abstract = {We present a new algorithm to construct a (generalized) deterministic Rabin automaton for an LTL formula φ. The automaton is the product of a master automaton and an array of slave automata, one for each G-subformula of φ. The slave automaton for G ψ is in charge of recognizing whether FG ψ holds. As opposed to standard determinization procedures, the states of all our automata have a clear logical structure, which allows for various optimizations. Our construction subsumes former algorithms for fragments of LTL. Experimental results show improvement in the sizes of the resulting automata compared to existing methods.},
author = {Esparza, Javier and Kretinsky, Jan},
pages = {192 -- 208},
publisher = {Springer},
title = {{From LTL to deterministic automata: A safraless compositional approach}},
doi = {10.1007/978-3-319-08867-9_13},
volume = {8559},
year = {2014},
}
@article{2208,
abstract = {We propose to detect quadrupole interactions of neutral ultracold atoms via their induced mean-field shift. We consider a Mott insulator state of spin-polarized atoms in a two-dimensional optical square lattice. The quadrupole moments of the atoms are aligned by an external magnetic field. As the alignment angle is varied, the mean-field shift shows a characteristic angular dependence, which constitutes the defining signature of the quadrupole interaction. For the 3P2 states of Yb and Sr atoms, we find a frequency shift of the order of tens of Hertz, which can be realistically detected in experiment with current technology. We compare our results to the mean-field shift of a spin-polarized quasi-two-dimensional Fermi gas in continuum. },
author = {Lahrz, Martin and Lemeshko, Mikhail and Sengstock, Klaus and Becker, Christoph and Mathey, Ludwig},
journal = {Physical Review A - Atomic, Molecular, and Optical Physics},
number = {4},
publisher = {American Physical Society},
title = {{Detecting quadrupole interactions in ultracold Fermi gases}},
doi = {10.1103/PhysRevA.89.043616},
volume = {89},
year = {2014},
}
@article{2211,
abstract = {In two-player finite-state stochastic games of partial observation on graphs, in every state of the graph, the players simultaneously choose an action, and their joint actions determine a probability distribution over the successor states. The game is played for infinitely many rounds and thus the players construct an infinite path in the graph. We consider reachability objectives where the first player tries to ensure a target state to be visited almost-surely (i.e., with probability 1) or positively (i.e., with positive probability), no matter the strategy of the second player. We classify such games according to the information and to the power of randomization available to the players. On the basis of information, the game can be one-sided with either (a) player 1, or (b) player 2 having partial observation (and the other player has perfect observation), or two-sided with (c) both players having partial observation. On the basis of randomization, (a) the players may not be allowed to use randomization (pure strategies), or (b) they may choose a probability distribution over actions but the actual random choice is external and not visible to the player (actions invisible), or (c) they may use full randomization. Our main results for pure strategies are as follows: (1) For one-sided games with player 2 having perfect observation we show that (in contrast to full randomized strategies) belief-based (subset-construction based) strategies are not sufficient, and we present an exponential upper bound on memory both for almost-sure and positive winning strategies; we show that the problem of deciding the existence of almost-sure and positive winning strategies for player 1 is EXPTIME-complete and present symbolic algorithms that avoid the explicit exponential construction. (2) For one-sided games with player 1 having perfect observation we show that nonelementarymemory is both necessary and sufficient for both almost-sure and positive winning strategies. (3) We show that for the general (two-sided) case finite-memory strategies are sufficient for both positive and almost-sure winning, and at least nonelementary memory is required. We establish the equivalence of the almost-sure winning problems for pure strategies and for randomized strategies with actions invisible. Our equivalence result exhibit serious flaws in previous results of the literature: we show a nonelementary memory lower bound for almost-sure winning whereas an exponential upper bound was previously claimed.},
author = {Chatterjee, Krishnendu and Doyen, Laurent},
journal = {ACM Transactions on Computational Logic (TOCL)},
number = {2},
publisher = {ACM},
title = {{Partial-observation stochastic games: How to win when belief fails}},
doi = {10.1145/2579821},
volume = {15},
year = {2014},
}
@inproceedings{2213,
abstract = {We consider two-player partial-observation stochastic games on finitestate graphs where player 1 has partial observation and player 2 has perfect observation. The winning condition we study are ε-regular conditions specified as parity objectives. The qualitative-analysis problem given a partial-observation stochastic game and a parity objective asks whether there is a strategy to ensure that the objective is satisfied with probability 1 (resp. positive probability). These qualitative-analysis problems are known to be undecidable. However in many applications the relevant question is the existence of finite-memory strategies, and the qualitative-analysis problems under finite-memory strategies was recently shown to be decidable in 2EXPTIME.We improve the complexity and show that the qualitative-analysis problems for partial-observation stochastic parity games under finite-memory strategies are EXPTIME-complete; and also establish optimal (exponential) memory bounds for finite-memory strategies required for qualitative analysis.},
author = {Chatterjee, Krishnendu and Doyen, Laurent and Nain, Sumit and Vardi, Moshe},
location = {Grenoble, France},
pages = {242 -- 257},
publisher = {Springer},
title = {{The complexity of partial-observation stochastic parity games with finite-memory strategies}},
doi = {10.1007/978-3-642-54830-7_16},
volume = {8412},
year = {2014},
}
@article{2214,
abstract = {A hallmark of immune cell trafficking is directional guidance via gradients of soluble or surface bound chemokines. Vascular endothelial cells produce, transport and deposit either their own chemokines or chemokines produced by the underlying stroma. Endothelial heparan sulfate (HS) was suggested to be a critical scaffold for these chemokine pools, but it is unclear how steep chemokine gradients are sustained between the lumenal and ablumenal aspects of blood vessels. Addressing this question by semi-quantitative immunostaining of HS moieties around blood vessels with a pan anti-HS IgM mAb, we found a striking HS enrichment in the basal lamina of resting and inflamed post capillary skin venules, as well as in high endothelial venules (HEVs) of lymph nodes. Staining of skin vessels with a glycocalyx probe further suggested that their lumenal glycocalyx contains much lower HS density than their basolateral extracellular matrix (ECM). This polarized HS pattern was observed also in isolated resting and inflamed microvascular dermal cells. Notably, progressive skin inflammation resulted in massive ECM deposition and in further HS enrichment around skin post capillary venules and their associated pericytes. Inflammation-dependent HS enrichment was not compromised in mice deficient in the main HS degrading enzyme, heparanase. Our results suggest that the blood vasculature patterns steep gradients of HS scaffolds between their lumenal and basolateral endothelial aspects, and that inflammatory processes can further enrich the HS content nearby inflamed vessels. We propose that chemokine gradients between the lumenal and ablumenal sides of vessels could be favored by these sharp HS scaffold gradients.},
author = {Stoler Barak, Liat and Moussion, Christine and Shezen, Elias and Hatzav, Miki and Sixt, Michael K and Alon, Ronen},
journal = {PLoS One},
number = {1},
publisher = {Public Library of Science},
title = {{Blood vessels pattern heparan sulfate gradients between their apical and basolateral aspects}},
doi = {10.1371/journal.pone.0085699},
volume = {9},
year = {2014},
}
@inproceedings{2216,
abstract = {The edit distance between two (untimed) traces is the minimum cost of a sequence of edit operations (insertion, deletion, or substitution) needed to transform one trace to the other. Edit distances have been extensively studied in the untimed setting, and form the basis for approximate matching of sequences in different domains such as coding theory, parsing, and speech recognition. In this paper, we lift the study of edit distances from untimed languages to the timed setting. We define an edit distance between timed words which incorporates both the edit distance between the untimed words and the absolute difference in time stamps. Our edit distance between two timed words is computable in polynomial time. Further, we show that the edit distance between a timed word and a timed language generated by a timed automaton, defined as the edit distance between the word and the closest word in the language, is PSPACE-complete. While computing the edit distance between two timed automata is undecidable, we show that the approximate version, where we decide if the edit distance between two timed automata is either less than a given parameter or more than δ away from the parameter, for δ > 0, can be solved in exponential space and is EXPSPACE-hard. Our definitions and techniques can be generalized to the setting of hybrid systems, and analogous decidability results hold for rectangular automata.},
author = {Chatterjee, Krishnendu and Ibsen-Jensen, Rasmus and Majumdar, Ritankar},
location = {Berlin, Germany},
pages = {303 -- 312},
publisher = {Springer},
title = {{Edit distance for timed automata}},
doi = {10.1145/2562059.2562141},
year = {2014},
}
@inproceedings{2218,
abstract = {While fixing concurrency bugs, program repair algorithms may introduce new concurrency bugs. We present an algorithm that avoids such regressions. The solution space is given by a set of program transformations we consider in the repair process. These include reordering of instructions within a thread and inserting atomic sections. The new algorithm learns a constraint on the space of candidate solutions, from both positive examples (error-free traces) and counterexamples (error traces). From each counterexample, the algorithm learns a constraint necessary to remove the errors. From each positive examples, it learns a constraint that is necessary in order to prevent the repair from turning the trace into an error trace. We implemented the algorithm and evaluated it on simplified Linux device drivers with known bugs.},
author = {Cerny, Pavol and Henzinger, Thomas A and Radhakrishna, Arjun and Ryzhyk, Leonid and Tarrach, Thorsten},
isbn = {978-331908866-2},
location = {Vienna, Austria},
pages = {568 -- 584},
publisher = {Springer},
title = {{Regression-free synthesis for concurrency}},
doi = {10.1007/978-3-319-08867-9_38},
volume = {8559},
year = {2014},
}
@inproceedings{2219,
abstract = {Recently, Döttling et al. (ASIACRYPT 2012) proposed the first chosen-ciphertext (IND-CCA) secure public-key encryption scheme from the learning parity with noise (LPN) assumption. In this work we give an alternative scheme which is conceptually simpler and more efficient. At the core of our construction is a trapdoor technique originally proposed for lattices by Micciancio and Peikert (EUROCRYPT 2012), which we adapt to the LPN setting. The main technical tool is a new double-trapdoor mechanism, together with a trapdoor switching lemma based on a computational variant of the leftover hash lemma.},
author = {Kiltz, Eike and Masny, Daniel and Pietrzak, Krzysztof Z},
isbn = {978-364254630-3},
pages = {1 -- 18},
publisher = {Springer},
title = {{Simple chosen-ciphertext security from low noise LPN}},
doi = {10.1007/978-3-642-54631-0_1},
volume = {8383},
year = {2014},
}
@article{2220,
abstract = {In this issue of Chemistry & Biology, Cokol and colleagues report a systematic study of drug interactions between antifungal compounds. Suppressive drug interactions occur more frequently than previously realized and come in different flavors with interesting implications.},
author = {De Vos, Marjon and Bollenbach, Mark Tobias},
issn = {10745521},
journal = {Chemistry and Biology},
number = {4},
pages = {439 -- 440},
publisher = {Cell Press},
title = {{Suppressive drug interactions between antifungals}},
doi = {10.1016/j.chembiol.2014.04.004},
volume = {21},
year = {2014},
}
@article{2223,
abstract = {Correct positioning of membrane proteins is an essential process in eukaryotic organisms. The plant hormone auxin is distributed through intercellular transport and triggers various cellular responses. Auxin transporters of the PIN-FORMED (PIN) family localize asymmetrically at the plasma membrane (PM) and mediate the directional transport of auxin between cells. A fungal toxin, brefeldin A (BFA), inhibits a subset of guanine nucleotide exchange factors for ADP-ribosylation factor small GTPases (ARF GEFs) including GNOM, which plays a major role in localization of PIN1 predominantly to the basal side of the PM. The Arabidopsis genome encodes 19 ARF-related putative GTPases. However, ARF components involved in PIN1 localization have been genetically poorly defined. Using a fluorescence imaging-based forward genetic approach, we identified an Arabidopsis mutant, bfa-visualized exocytic trafficking defective1 (bex1), in which PM localization of PIN1-green fluorescent protein (GFP) as well as development is hypersensitive to BFA. We found that in bex1 a member of the ARF1 gene family, ARF1A1C, was mutated. ARF1A1C localizes to the trans-Golgi network/early endosome and Golgi apparatus, acts synergistically to BEN1/MIN7 ARF GEF and is important for PIN recycling to the PM. Consistent with the developmental importance of PIN proteins, functional interference with ARF1 resulted in an impaired auxin response gradient and various developmental defects including embryonic patterning defects and growth arrest. Our results show that ARF1A1C is essential for recycling of PIN auxin transporters and for various auxin-dependent developmental processes.},
author = {Tanaka, Hirokazu and Nodzyński, Tomasz and Kitakura, Saeko and Feraru, Mugurel and Sasabe, Michiko and Ishikawa, Tomomi and Kleine Vehn, Jürgen and Kakimoto, Tatsuo and Friml, Jirí},
issn = {00320781},
journal = {Plant and Cell Physiology},
number = {4},
pages = {737 -- 749},
publisher = {Oxford University Press},
title = {{BEX1/ARF1A1C is required for BFA-sensitive recycling of PIN auxin transporters and auxin-mediated development in arabidopsis}},
doi = {10.1093/pcp/pct196},
volume = {55},
year = {2014},
}
@article{2225,
abstract = {We consider sample covariance matrices of the form X∗X, where X is an M×N matrix with independent random entries. We prove the isotropic local Marchenko-Pastur law, i.e. we prove that the resolvent (X∗X−z)−1 converges to a multiple of the identity in the sense of quadratic forms. More precisely, we establish sharp high-probability bounds on the quantity ⟨v,(X∗X−z)−1w⟩−⟨v,w⟩m(z), where m is the Stieltjes transform of the Marchenko-Pastur law and v,w∈CN. We require the logarithms of the dimensions M and N to be comparable. Our result holds down to scales Iz≥N−1+ε and throughout the entire spectrum away from 0. We also prove analogous results for generalized Wigner matrices.
},
author = {Bloemendal, Alex and Erdös, László and Knowles, Antti and Yau, Horng and Yin, Jun},
issn = {10836489},
journal = {Electronic Journal of Probability},
publisher = {Institute of Mathematical Statistics},
title = {{Isotropic local laws for sample covariance and generalized Wigner matrices}},
doi = {10.1214/EJP.v19-3054},
volume = {19},
year = {2014},
}
@article{2226,
abstract = {Coriolis force effects on shear flows are important in geophysical and astrophysical contexts. We report a study on the linear stability and the transient energy growth of the plane Couette flow with system rotation perpendicular to the shear direction. External rotation causes linear instability. At small rotation rates, the onset of linear instability scales inversely with the rotation rate and the optimal transient growth in the linearly stable region is slightly enhanced ∼Re2. The corresponding optimal initial perturbations are characterized by roll structures inclined in the streamwise direction and are twisted under external rotation. At large rotation rates, the transient growth is significantly inhibited and hence linear stability analysis is a reliable indicator for instability.},
author = {Shi, Liang and Hof, Björn and Tilgner, Andreas},
issn = {15393755},
journal = {Physical Review E Statistical Nonlinear and Soft Matter Physics},
number = {1},
publisher = {American Institute of Physics},
title = {{Transient growth of Ekman-Couette flow}},
doi = {10.1103/PhysRevE.89.013001},
volume = {89},
year = {2014},
}
@article{2228,
abstract = {Fast-spiking, parvalbumin-expressing GABAergic interneurons, a large proportion of which are basket cells (BCs), have a key role in feedforward and feedback inhibition, gamma oscillations and complex information processing. For these functions, fast propagation of action potentials (APs) from the soma to the presynaptic terminals is important. However, the functional properties of interneuron axons remain elusive. We examined interneuron axons by confocally targeted subcellular patch-clamp recording in rat hippocampal slices. APs were initiated in the proximal axon ∼20 μm from the soma and propagated to the distal axon with high reliability and speed. Subcellular mapping revealed a stepwise increase of Na^+ conductance density from the soma to the proximal axon, followed by a further gradual increase in the distal axon. Active cable modeling and experiments with partial channel block revealed that low axonal Na^+ conductance density was sufficient for reliability, but high Na^+ density was necessary for both speed of propagation and fast-spiking AP phenotype. Our results suggest that a supercritical density of Na^+ channels compensates for the morphological properties of interneuron axons (small segmental diameter, extensive branching and high bouton density), ensuring fast AP propagation and high-frequency repetitive firing.},
author = {Hu, Hua and Jonas, Peter M},
issn = {10976256},
journal = {Nature Neuroscience},
number = {5},
pages = {686--693},
publisher = {Nature Publishing Group},
title = {{A supercritical density of Na^+ channels ensures fast signaling in GABAergic interneuron axons}},
doi = {10.1038/nn.3678},
volume = {17},
year = {2014},
}
@article{2229,
abstract = {The distance between Ca^2+ channels and release sensors determines the speed and efficacy of synaptic transmission. Tight "nanodomain" channel-sensor coupling initiates transmitter release at synapses in the mature brain, whereas loose "microdomain" coupling appears restricted to early developmental stages. To probe the coupling configuration at a plastic synapse in the mature central nervous system, we performed paired recordings between mossy fiber terminals and CA3 pyramidal neurons in rat hippocampus. Millimolar concentrations of both the fast Ca^2+ chelator BAPTA [1,2-bis(2-aminophenoxy)ethane- N,N, N′,N′-tetraacetic acid] and the slow chelator EGTA efficiently suppressed transmitter release, indicating loose coupling between Ca^2+ channels and release sensors. Loose coupling enabled the control of initial release probability by fast endogenous Ca^2+ buffers and the generation of facilitation by buffer saturation. Thus, loose coupling provides the molecular framework for presynaptic plasticity.},
author = {Vyleta, Nicholas and Jonas, Peter M},
issn = {00368075},
journal = {Science},
number = {6171},
pages = {665 -- 670},
publisher = {American Association for the Advancement of Science},
title = {{Loose coupling between Ca^2+ channels and release sensors at a plastic hippocampal synapse}},
doi = {10.1126/science.1244811},
volume = {343},
year = {2014},
}
@article{2230,
abstract = {Intracellular electrophysiological recordings provide crucial insights into elementary neuronal signals such as action potentials and synaptic currents. Analyzing and interpreting these signals is essential for a quantitative understanding of neuronal information processing, and requires both fast data visualization and ready access to complex analysis routines. To achieve this goal, we have developed Stimfit, a free software package for cellular neurophysiology with a Python scripting interface and a built-in Python shell. The program supports most standard file formats for cellular neurophysiology and other biomedical signals through the Biosig library. To quantify and interpret the activity of single neurons and communication between neurons, the program includes algorithms to characterize the kinetics of presynaptic action potentials and postsynaptic currents, estimate latencies between pre- and postsynaptic events, and detect spontaneously occurring events. We validate and benchmark these algorithms, give estimation errors, and provide sample use cases, showing that Stimfit represents an efficient, accessible and extensible way to accurately analyze and interpret neuronal signals.},
author = {Guzmán, José and Schlögl, Alois and Schmidt Hieber, Christoph},
issn = {16625196},
journal = {Frontiers in Neuroinformatics},
number = {FEB},
publisher = {Frontiers Research Foundation},
title = {{Stimfit: Quantifying electrophysiological data with Python}},
doi = {10.3389/fninf.2014.00016},
volume = {8},
year = {2014},
}
@article{2231,
abstract = {Based on the measurements of noise in gene expression performed during the past decade, it has become customary to think of gene regulation in terms of a two-state model, where the promoter of a gene can stochastically switch between an ON and an OFF state. As experiments are becoming increasingly precise and the deviations from the two-state model start to be observable, we ask about the experimental signatures of complex multistate promoters, as well as the functional consequences of this additional complexity. In detail, we i), extend the calculations for noise in gene expression to promoters described by state transition diagrams with multiple states, ii), systematically compute the experimentally accessible noise characteristics for these complex promoters, and iii), use information theory to evaluate the channel capacities of complex promoter architectures and compare them with the baseline provided by the two-state model. We find that adding internal states to the promoter generically decreases channel capacity, except in certain cases, three of which (cooperativity, dual-role regulation, promoter cycling) we analyze in detail.},
author = {Rieckh, Georg and Tkacik, Gasper},
issn = {00063495},
journal = {Biophysical Journal},
number = {5},
pages = {1194 -- 1204},
publisher = {Biophysical Society},
title = {{Noise and information transmission in promoters with multiple internal states}},
doi = {10.1016/j.bpj.2014.01.014},
volume = {106},
year = {2014},
}
@article{2232,
abstract = {The purpose of this contribution is to summarize and discuss recent advances regarding the onset of turbulence in shear flows. The absence of a clear-cut instability mechanism, the spatio-temporal intermittent character and extremely long lived transients are some of the major difficulties encountered in these flows and have hindered progress towards understanding the transition process. We will show for the case of pipe flow that concepts from nonlinear dynamics and statistical physics can help to explain the onset of turbulence. In particular, the turbulent structures (puffs) observed close to onset are spatially localized chaotic transients and their lifetimes increase super-exponentially with Reynolds number. At the same time fluctuations of individual turbulent puffs can (although very rarely) lead to the nucleation of new puffs. The competition between these two stochastic processes gives rise to a non-equilibrium phase transition where turbulence changes from a super-transient to a sustained state.},
author = {Song, Baofang and Hof, Björn},
issn = {17425468},
journal = {Journal of Statistical Mechanics Theory and Experiment},
number = {2},
publisher = {IOP Publishing Ltd.},
title = {{Deterministic and stochastic aspects of the transition to turbulence}},
doi = {10.1088/1742-5468/2014/02/P02001},
volume = {2014},
year = {2014},
}
@article{2233,
abstract = { A discounted-sum automaton (NDA) is a nondeterministic finite automaton with edge weights, valuing a run by the discounted sum of visited edge weights. More precisely, the weight in the i-th position of the run is divided by λi, where the discount factor λ is a fixed rational number greater than 1. The value of a word is the minimal value of the automaton runs on it. Discounted summation is a common and useful measuring scheme, especially for infinite sequences, reflecting the assumption that earlier weights are more important than later weights. Unfortunately, determinization of NDAs, which is often essential in formal verification, is, in general, not possible. We provide positive news, showing that every NDA with an integral discount factor is determinizable. We complete the picture by proving that the integers characterize exactly the discount factors that guarantee determinizability: for every nonintegral rational discount factor λ, there is a nondeterminizable λ-NDA. We also prove that the class of NDAs with integral discount factors enjoys closure under the algebraic operations min, max, addition, and subtraction, which is not the case for general NDAs nor for deterministic NDAs. For general NDAs, we look into approximate determinization, which is always possible as the influence of a word's suffix decays. We show that the naive approach, of unfolding the automaton computations up to a sufficient level, is doubly exponential in the discount factor. We provide an alternative construction for approximate determinization, which is singly exponential in the discount factor, in the precision, and in the number of states. We also prove matching lower bounds, showing that the exponential dependency on each of these three parameters cannot be avoided. All our results hold equally for automata over finite words and for automata over infinite words. },
author = {Boker, Udi and Henzinger, Thomas A},
issn = {18605974},
journal = {Logical Methods in Computer Science},
number = {1},
publisher = {International Federation of Computational Logic},
title = {{Exact and approximate determinization of discounted-sum automata}},
doi = {10.2168/LMCS-10(1:10)2014},
volume = {10},
year = {2014},
}
@article{2234,
abstract = {We study Markov decision processes (MDPs) with multiple limit-average (or mean-payoff) functions. We consider two different objectives, namely, expectation and satisfaction objectives. Given an MDP with κ limit-average functions, in the expectation objective the goal is to maximize the expected limit-average value, and in the satisfaction objective the goal is to maximize the probability of runs such that the limit-average value stays above a given vector. We show that under the expectation objective, in contrast to the case of one limit-average function, both randomization and memory are necessary for strategies even for ε-approximation, and that finite-memory randomized strategies are sufficient for achieving Pareto optimal values. Under the satisfaction objective, in contrast to the case of one limit-average function, infinite memory is necessary for strategies achieving a specific value (i.e. randomized finite-memory strategies are not sufficient), whereas memoryless randomized strategies are sufficient for ε-approximation, for all ε > 0. We further prove that the decision problems for both expectation and satisfaction objectives can be solved in polynomial time and the trade-off curve (Pareto curve) can be ε-approximated in time polynomial in the size of the MDP and 1/ε, and exponential in the number of limit-average functions, for all ε > 0. Our analysis also reveals flaws in previous work for MDPs with multiple mean-payoff functions under the expectation objective, corrects the flaws, and allows us to obtain improved results.},
author = {Brázdil, Tomáš and Brožek, Václav and Chatterjee, Krishnendu and Forejt, Vojtěch and Kučera, Antonín},
issn = {18605974},
journal = {Logical Methods in Computer Science},
number = {1},
publisher = {International Federation of Computational Logic},
title = {{Markov decision processes with multiple long-run average objectives}},
doi = {10.2168/LMCS-10(1:13)2014},
volume = {10},
year = {2014},
}
@article{2235,
abstract = {Emerging infectious diseases (EIDs) pose a risk to human welfare, both directly and indirectly, by affecting managed livestock and wildlife that provide valuable resources and ecosystem services, such as the pollination of crops. Honeybees (Apis mellifera), the prevailing managed insect crop pollinator, suffer from a range of emerging and exotic high-impact pathogens, and population maintenance requires active management by beekeepers to control them. Wild pollinators such as bumblebees (Bombus spp.) are in global decline, one cause of which may be pathogen spillover from managed pollinators like honeybees or commercial colonies of bumblebees. Here we use a combination of infection experiments and landscape-scale field data to show that honeybee EIDs are indeed widespread infectious agents within the pollinator assemblage. The prevalence of deformed wing virus (DWV) and the exotic parasite Nosema ceranae in honeybees and bumblebees is linked; as honeybees have higher DWV prevalence, and sympatric bumblebees and honeybees are infected by the same DWV strains, Apis is the likely source of at least one major EID in wild pollinators. Lessons learned from vertebrates highlight the need for increased pathogen control in managed bee species to maintain wild pollinators, as declines in native pollinators may be caused by interspecies pathogen transmission originating from managed pollinators.},
author = {Fürst, Matthias and Mcmahon, Dino and Osborne, Juliet and Paxton, Robert and Brown, Mark},
issn = {00280836},
journal = {Nature},
number = {7488},
pages = {364 -- 366},
publisher = {Nature Publishing Group},
title = {{Disease associations between honeybees and bumblebees as a threat to wild pollinators}},
doi = {10.1038/nature12977},
volume = {506},
year = {2014},
}
@inproceedings{2236,
abstract = {Consider a joint distribution (X,A) on a set. We show that for any family of distinguishers, there exists a simulator such that 1 no function in can distinguish (X,A) from (X,h(X)) with advantage ε, 2 h is only O(2 3ℓ ε -2) times less efficient than the functions in. For the most interesting settings of the parameters (in particular, the cryptographic case where X has superlogarithmic min-entropy, ε > 0 is negligible and consists of circuits of polynomial size), we can make the simulator h deterministic. As an illustrative application of our theorem, we give a new security proof for the leakage-resilient stream-cipher from Eurocrypt'09. Our proof is simpler and quantitatively much better than the original proof using the dense model theorem, giving meaningful security guarantees if instantiated with a standard blockcipher like AES. Subsequent to this work, Chung, Lui and Pass gave an interactive variant of our main theorem, and used it to investigate weak notions of Zero-Knowledge. Vadhan and Zheng give a more constructive version of our theorem using their new uniform min-max theorem.},
author = {Jetchev, Dimitar and Pietrzak, Krzysztof Z},
editor = {Lindell, Yehuda},
isbn = {978-364254241-1},
location = {San Diego, USA},
pages = {566 -- 590},
publisher = {Springer},
title = {{How to fake auxiliary input}},
doi = {10.1007/978-3-642-54242-8_24},
volume = {8349},
year = {2014},
}
@article{2246,
abstract = {Muller games are played by two players moving a token along a graph; the winner is determined by the set of vertices that occur infinitely often. The central algorithmic problem is to compute the winning regions for the players. Different classes and representations of Muller games lead to problems of varying computational complexity. One such class are parity games; these are of particular significance in computational complexity, as they remain one of the few combinatorial problems known to be in NP ∩ co-NP but not known to be in P. We show that winning regions for a Muller game can be determined from the alternating structure of its traps. To every Muller game we then associate a natural number that we call its trap depth; this parameter measures how complicated the trap structure is. We present algorithms for parity games that run in polynomial time for graphs of bounded trap depth, and in general run in time exponential in the trap depth. },
author = {Grinshpun, Andrey and Phalitnonkiat, Pakawat and Rubin, Sasha and Tarfulea, Andrei},
issn = {03043975},
journal = {Theoretical Computer Science},
pages = {73 -- 91},
publisher = {Elsevier},
title = {{Alternating traps in Muller and parity games}},
doi = {10.1016/j.tcs.2013.11.032},
volume = {521},
year = {2014},
}
@article{2249,
abstract = {The unfolded protein response (UPR) is a signaling network triggered by overload of protein-folding demand in the endoplasmic reticulum (ER), a condition termed ER stress. The UPR is critical for growth and development; nonetheless, connections between the UPR and other cellular regulatory processes remain largely unknown. Here, we identify a link between the UPR and the phytohormone auxin, a master regulator of plant physiology. We show that ER stress triggers down-regulation of auxin receptors and transporters in Arabidopsis thaliana. We also demonstrate that an Arabidopsis mutant of a conserved ER stress sensor IRE1 exhibits defects in the auxin response and levels. These data not only support that the plant IRE1 is required for auxin homeostasis, they also reveal a species-specific feature of IRE1 in multicellular eukaryotes. Furthermore, by establishing that UPR activation is reduced in mutants of ER-localized auxin transporters, including PIN5, we define a long-neglected biological significance of ER-based auxin regulation. We further examine the functional relationship of IRE1 and PIN5 by showing that an ire1 pin5 triple mutant enhances defects of UPR activation and auxin homeostasis in ire1 or pin5. Our results imply that the plant UPR has evolved a hormone-dependent strategy for coordinating ER function with physiological processes.},
author = {Chen, Yani and Aung, Kyaw and Rolčík, Jakub and Walicki, Kathryn and Friml, Jirí and Brandizzí, Federica},
issn = {09607412},
journal = {Plant Journal},
number = {1},
pages = {97 -- 107},
publisher = {Wiley-Blackwell},
title = {{Inter-regulation of the unfolded protein response and auxin signaling}},
doi = {10.1111/tpj.12373},
volume = {77},
year = {2014},
}
@article{2250,
abstract = {The genome sequences of new viruses often contain many "orphan" or "taxon-specific" proteins apparently lacking homologs. However, because viral proteins evolve very fast, commonly used sequence similarity detection methods such as BLAST may overlook homologs. We analyzed a data set of proteins from RNA viruses characterized as "genus specific" by BLAST. More powerful methods developed recently, such as HHblits or HHpred (available through web-based, user-friendly interfaces), could detect distant homologs of a quarter of these proteins, suggesting that these methods should be used to annotate viral genomes. In-depth manual analyses of a subset of the remaining sequences, guided by contextual information such as taxonomy, gene order, or domain cooccurrence, identified distant homologs of another third. Thus, a combination of powerful automated methods and manual analyses can uncover distant homologs of many proteins thought to be orphans. We expect these methodological results to be also applicable to cellular organisms, since they generally evolve much more slowly than RNA viruses. As an application, we reanalyzed the genome of a bee pathogen, Chronic bee paralysis virus (CBPV). We could identify homologs of most of its proteins thought to be orphans; in each case, identifying homologs provided functional clues. We discovered that CBPV encodes a domain homologous to the Alphavirus methyltransferase-guanylyltransferase; a putative membrane protein, SP24, with homologs in unrelated insect viruses and insect-transmitted plant viruses having different morphologies (cileviruses, higreviruses, blunerviruses, negeviruses); and a putative virion glycoprotein, ORF2, also found in negeviruses. SP24 and ORF2 are probably major structural components of the virionsd.},
author = {Kuchibhatla, Durga and Sherman, Westley and Chung, Betty and Cook, Shelley and Schneider, Georg and Eisenhaber, Birgit and Karlin, David},
issn = {0022538X},
journal = {Journal of Virology},
number = {1},
pages = {10 -- 20},
publisher = {ASM},
title = {{Powerful sequence similarity search methods and in-depth manual analyses can identify remote homologs in many apparently "orphan" viral proteins}},
doi = {10.1128/JVI.02595-13},
volume = {88},
year = {2014},
}
@article{2251,
abstract = {Sharp wave/ripple (SWR, 150–250 Hz) hippocampal events have long been postulated to be involved in memory consolidation. However, more recent work has investigated SWRs that occur during active waking behaviour: findings that suggest that SWRs may also play a role in cell assembly strengthening or spatial working memory. Do such theories of SWR function apply to animal learning? This review discusses how general theories linking SWRs to memory-related function may explain circuit mechanisms related to rodent spatial learning and to the associated stabilization of new cognitive maps.},
author = {Csicsvari, Jozsef L and Dupret, David},
issn = {09628436},
journal = {Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences},
number = {1635},
publisher = {Royal Society, The},
title = {{Sharp wave/ripple network oscillations and learning-associated hippocampal maps}},
doi = {10.1098/rstb.2012.0528},
volume = {369},
year = {2014},
}
@article{2253,
abstract = {Plant growth is achieved predominantly by cellular elongation, which is thought to be controlled on several levels by apoplastic auxin. Auxin export into the apoplast is achieved by plasma membrane efflux catalysts of the PIN-FORMED (PIN) and ATP-binding cassette protein subfamily B/phosphor- glycoprotein (ABCB/PGP) classes; the latter were shown to depend on interaction with the FKBP42, TWISTED DWARF1 (TWD1). Here by using a transgenic approach in combination with phenotypical, biochemical and cell biological analyses we demonstrate the importance of a putative C-terminal in-plane membrane anchor of TWD1 in the regulation of ABCB-mediated auxin transport. In contrast with dwarfed twd1 loss-of-function alleles, TWD1 gain-of-function lines that lack a putative in-plane membrane anchor (HA-TWD1-Ct) show hypermorphic plant architecture, characterized by enhanced stem length and leaf surface but reduced shoot branching. Greater hypocotyl length is the result of enhanced cell elongation that correlates with reduced polar auxin transport capacity for HA-TWD1-Ct. As a consequence, HA-TWD1-Ct displays higher hypocotyl auxin accumulation, which is shown to result in elevated auxin-induced cell elongation rates. Our data highlight the importance of C-terminal membrane anchoring for TWD1 action, which is required for specific regulation of ABCB-mediated auxin transport. These data support a model in which TWD1 controls lateral ABCB1-mediated export into the apoplast, which is required for auxin-mediated cell elongation.},
author = {Bailly, Aurélien and Wang, Bangjun and Zwiewka, Marta and Pollmann, Stephan and Schenck, Daniel and Lüthen, Hartwig and Schulz, Alexander and Friml, Jirí and Geisler, Markus},
issn = {09607412},
journal = {Plant Journal},
number = {1},
pages = {108 -- 118},
publisher = {Wiley-Blackwell},
title = {{Expression of TWISTED DWARF1 lacking its in-plane membrane anchor leads to increased cell elongation and hypermorphic growth}},
doi = {10.1111/tpj.12369},
volume = {77},
year = {2014},
}
@article{2254,
abstract = {Theta-gamma network oscillations are thought to represent key reference signals for information processing in neuronal ensembles, but the underlying synaptic mechanisms remain unclear. To address this question, we performed whole-cell (WC) patch-clamp recordings from mature hippocampal granule cells (GCs) in vivo in the dentate gyrus of anesthetized and awake rats. GCs in vivo fired action potentials at low frequency, consistent with sparse coding in the dentate gyrus. GCs were exposed to barrages of fast AMPAR-mediated excitatory postsynaptic currents (EPSCs), primarily relayed from the entorhinal cortex, and inhibitory postsynaptic currents (IPSCs), presumably generated by local interneurons. EPSCs exhibited coherence with the field potential predominantly in the theta frequency band, whereas IPSCs showed coherence primarily in the gamma range. Action potentials in GCs were phase locked to network oscillations. Thus, theta-gamma-modulated synaptic currents may provide a framework for sparse temporal coding of information in the dentate gyrus.},
author = {Pernia-Andrade, Alejandro and Jonas, Peter M},
issn = {08966273},
journal = {Neuron},
number = {1},
pages = {140 -- 152},
publisher = {Elsevier},
title = {{Theta-gamma-modulated synaptic currents in hippocampal granule cells in vivo define a mechanism for network oscillations}},
doi = {10.1016/j.neuron.2013.09.046},
volume = {81},
year = {2014},
}
@article{2255,
abstract = {Motivated by applications in biology, we present an algorithm for estimating the length of tube-like shapes in 3-dimensional Euclidean space. In a first step, we combine the tube formula of Weyl with integral geometric methods to obtain an integral representation of the length, which we approximate using a variant of the Koksma-Hlawka Theorem. In a second step, we use tools from computational topology to decrease the dependence on small perturbations of the shape. We present computational experiments that shed light on the stability and the convergence rate of our algorithm.},
author = {Edelsbrunner, Herbert and Pausinger, Florian},
issn = {09249907},
journal = {Journal of Mathematical Imaging and Vision},
number = {1},
pages = {164 -- 177},
publisher = {Springer},
title = {{Stable length estimates of tube-like shapes}},
doi = {10.1007/s10851-013-0468-x},
volume = {50},
year = {2014},
}
@article{2257,
abstract = {Maximum entropy models are the least structured probability distributions that exactly reproduce a chosen set of statistics measured in an interacting network. Here we use this principle to construct probabilistic models which describe the correlated spiking activity of populations of up to 120 neurons in the salamander retina as it responds to natural movies. Already in groups as small as 10 neurons, interactions between spikes can no longer be regarded as small perturbations in an otherwise independent system; for 40 or more neurons pairwise interactions need to be supplemented by a global interaction that controls the distribution of synchrony in the population. Here we show that such “K-pairwise” models—being systematic extensions of the previously used pairwise Ising models—provide an excellent account of the data. We explore the properties of the neural vocabulary by: 1) estimating its entropy, which constrains the population's capacity to represent visual information; 2) classifying activity patterns into a small set of metastable collective modes; 3) showing that the neural codeword ensembles are extremely inhomogenous; 4) demonstrating that the state of individual neurons is highly predictable from the rest of the population, allowing the capacity for error correction.},
author = {Tkacik, Gasper and Marre, Olivier and Amodei, Dario and Schneidman, Elad and Bialek, William and Berry, Michael},
issn = {1553734X},
journal = {PLoS Computational Biology},
number = {1},
publisher = {Public Library of Science},
title = {{Searching for collective behavior in a large network of sensory neurons}},
doi = {10.1371/journal.pcbi.1003408},
volume = {10},
year = {2014},
}
@article{2261,
abstract = {To reveal the full potential of human pluripotent stem cells, new methods for rapid, site-specific genomic engineering are needed. Here, we describe a system for precise genetic modification of human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). We identified a novel human locus, H11, located in a safe, intergenic, transcriptionally active region of chromosome 22, as the recipient site, to provide robust, ubiquitous expression of inserted genes. Recipient cell lines were established by site-specific placement of a ‘landing pad’ cassette carrying attP sites for phiC31 and Bxb1 integrases at the H11 locus by spontaneous or TALEN-assisted homologous recombination. Dual integrase cassette exchange (DICE) mediated by phiC31 and Bxb1 integrases was used to insert genes of interest flanked by phiC31 and Bxb1 attB sites at the H11 locus, replacing the landing pad. This system provided complete control over content, direction and copy number of inserted genes, with a specificity of 100%. A series of genes, including mCherry and various combinations of the neural transcription factors LMX1a, FOXA2 and OTX2, were inserted in recipient cell lines derived from H9 ESC, as well as iPSC lines derived from a Parkinson’s disease patient and a normal sibling control. The DICE system offers rapid, efficient and precise gene insertion in ESC and iPSC and is particularly well suited for repeated modifications of the same locus.},
author = {Zhu, Fangfang and Gamboa, Matthew and Farruggio, Alfonso and Hippenmeyer, Simon and Tasic, Bosiljka and Schüle, Birgitt and Chen Tsai, Yanru and Calos, Michele},
journal = {Nucleic Acids Research},
number = {5},
publisher = {Oxford University Press},
title = {{DICE, an efficient system for iterative genomic editing in human pluripotent stem cells}},
doi = {10.1093/nar/gkt1290},
volume = {42},
year = {2014},
}
@inproceedings{2275,
abstract = {Energies with high-order non-submodular interactions have been shown to be very useful in vision due to their high modeling power. Optimization of such energies, however, is generally NP-hard. A naive approach that works for small problem instances is exhaustive search, that is, enumeration of all possible labelings of the underlying graph. We propose a general minimization approach for large graphs based on enumeration of labelings of certain small patches.
This partial enumeration technique reduces complex high-order energy formulations to pairwise Constraint Satisfaction Problems with unary costs (uCSP), which can be efficiently solved using standard methods like TRW-S. Our approach outperforms a number of existing state-of-the-art algorithms on well known difficult problems (e.g. curvature regularization, stereo, deconvolution); it gives near global minimum and better speed.
Our main application of interest is curvature regularization. In the context of segmentation, our partial enumeration technique allows to evaluate curvature directly on small patches using a novel integral geometry approach.
},
author = {Olsson, Carl and Ulen, Johannes and Boykov, Yuri and Kolmogorov, Vladimir},
location = {Sydney, Australia},
pages = {2936 -- 2943},
publisher = {IEEE},
title = {{Partial enumeration and curvature regularization}},
doi = {10.1109/ICCV.2013.365},
year = {2014},
}
@article{2281,
abstract = {We consider two-dimensional Bose-Einstein condensates with attractive interaction, described by the Gross-Pitaevskii functional. Minimizers of this functional exist only if the interaction strength a satisfies {Mathematical expression}, where Q is the unique positive radial solution of {Mathematical expression} in {Mathematical expression}. We present a detailed analysis of the behavior of minimizers as a approaches a*, where all the mass concentrates at a global minimum of the trapping potential.},
author = {Guo, Yujin and Seiringer, Robert},
journal = {Letters in Mathematical Physics},
number = {2},
pages = {141 -- 156},
publisher = {Springer},
title = {{On the mass concentration for Bose-Einstein condensates with attractive interactions}},
doi = {10.1007/s11005-013-0667-9},
volume = {104},
year = {2014},
}
@article{2285,
abstract = {GABAergic inhibitory interneurons control fundamental aspects of neuronal network function. Their functional roles are assumed to be defined by the identity of their input synapses, the architecture of their dendritic tree, the passive and active membrane properties and finally the nature of their postsynaptic targets. Indeed, interneurons display a high degree of morphological and physiological heterogeneity. However, whether their morphological and physiological characteristics are correlated and whether interneuron diversity can be described by a continuum of GABAergic cell types or by distinct classes has remained unclear. Here we perform a detailed morphological and physiological characterization of GABAergic cells in the dentate gyrus, the input region of the hippocampus. To achieve an unbiased and efficient sampling and classification we used knock-in mice expressing the enhanced green fluorescent protein (eGFP) in glutamate decarboxylase 67 (GAD67)-positive neurons and performed cluster analysis. We identified five interneuron classes, each of them characterized by a distinct set of anatomical and physiological parameters. Cross-correlation analysis further revealed a direct relation between morphological and physiological properties indicating that dentate gyrus interneurons fall into functionally distinct classes which may differentially control neuronal network activity.},
author = {Hosp, Jonas and Strüber, Michael and Yanagawa, Yuchio and Obata, Kunihiko and Vida, Imre and Jonas, Peter M and Bartos, Marlene},
journal = {Hippocampus},
number = {2},
pages = {189 -- 203},
publisher = {Wiley-Blackwell},
title = {{Morpho-physiological criteria divide dentate gyrus interneurons into classes}},
doi = {10.1002/hipo.22214},
volume = {23},
year = {2014},
}
@article{2407,
abstract = {Two definitions of the effective mass of a particle interacting with a quantum field, such as a polaron, are considered and shown to be equal in models similar to the Fröhlich polaron model. These are: 1. the mass defined by the low momentum energy E(P)≈E(0)+P2/2 M of the translation invariant system constrained to have momentum P and 2. the mass M of a simple particle in an arbitrary slowly varying external potential, V, described by the nonrelativistic Schrödinger equation, whose ground state energy equals that of the combined particle/field system in a bound state in the same V.},
author = {Lieb, Élliott and Seiringer, Robert},
journal = {Journal of Statistical Physics},
number = {1-2},
pages = {51 -- 57},
publisher = {Springer},
title = {{Equivalence of two definitions of the effective mass of a polaron}},
doi = {10.1007/s10955-013-0791-z},
volume = {154},
year = {2014},
}
@article{248,
abstract = {For any pencil of conics or higher-dimensional quadrics over ℚ, with all degenerate fibres defined over ℚ, we show that the Brauer–Manin obstruction controls weak approximation. The proof is based on the Hasse principle and weak approximation for some special intersections of quadrics over ℚ, which is a consequence of recent advances in additive combinatorics.},
author = {Timothy Browning and Matthiesen, Lilian and Skorobogatov, Alexei N},
journal = {Annals of Mathematics},
number = {1},
pages = {381 -- 402},
publisher = {John Hopkins University Press},
title = {{Rational points on pencils of conics and quadrics with many degenerate fibres}},
doi = {https://doi.org/10.4007/annals.2014.180.1.8},
volume = {180},
year = {2014},
}
@article{7598,
author = {Tan, Shutang and Xue, Hong-Wei},
issn = {2211-1247},
journal = {Cell Reports},
number = {5},
pages = {1692--1702},
publisher = {Elsevier},
title = {{Casein kinase 1 regulates ethylene synthesis by phosphorylating and promoting the turnover of ACS5}},
doi = {10.1016/j.celrep.2014.10.047},
volume = {9},
year = {2014},
}
@article{7771,
abstract = {In their Letter, Schreck, Bertrand, O'Hern and Shattuck [Phys. Rev. Lett. 107, 078301 (2011)] study nonlinearities in jammed particulate systems that arise when contacts are altered. They conclude that there is "no harmonic regime in the large system limit for all compressions" and "at jamming onset for any system size." Their argument rests on the claim that for finite-range repulsive potentials, of the form used in studies of jamming, the breaking or forming of a single contact is sufficient to destroy the linear regime. We dispute these conclusions and argue that linear response is both justified and essential for understanding the nature of the jammed solid. },
author = {Goodrich, Carl Peter and Liu, Andrea J. and Nagel, Sidney R.},
issn = {0031-9007},
journal = {Physical Review Letters},
number = {4},
publisher = {American Physical Society},
title = {{Comment on “Repulsive contact interactions make jammed particulate systems inherently nonharmonic”}},
doi = {10.1103/physrevlett.112.049801},
volume = {112},
year = {2014},
}
@article{451,
abstract = {We introduce algorithms for the computation of homology, cohomology, and related operations on cubical cell complexes, using the technique based on a chain contraction from the original chain complex to a reduced one that represents its homology. This work is based on previous results for simplicial complexes, and uses Serre’s diagonalization for cubical cells. An implementation in C++ of the introduced algorithms is available at http://www.pawelpilarczyk.com/chaincon/ together with some examples. The paper is self-contained as much as possible, and is written at a very elementary level, so that basic knowledge of algebraic topology should be sufficient to follow it.},
author = {Pawel Pilarczyk and Real, Pedro},
journal = {Advances in Computational Mathematics},
number = {1},
pages = {253 -- 275},
publisher = {Kluwer},
title = {{Computation of cubical homology, cohomology, and (co)homological operations via chain contraction}},
doi = {10.1007/s10444-014-9356-1},
volume = {41},
year = {2014},
}
@article{468,
abstract = {Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance) is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss.},
author = {Cimadom, Arno and Ulloa, Angel and Meidl, Patrick and Zöttl, Markus and Zöttl, Elisabet and Fessl, Birgit and Nemeth, Erwin and Dvorak, Michael and Cunninghame, Francesca and Tebbich, Sabine},
journal = {PLoS One},
number = {9},
publisher = {Public Library of Science},
title = {{Invasive parasites habitat change and heavy rainfall reduce breeding success in Darwin's finches}},
doi = {10.1371/journal.pone.0107518},
volume = {9},
year = {2014},
}
@inproceedings{475,
abstract = {First cycle games (FCG) are played on a finite graph by two players who push a token along the edges until a vertex is repeated, and a simple cycle is formed. The winner is determined by some fixed property Y of the sequence of labels of the edges (or nodes) forming this cycle. These games are traditionally of interest because of their connection with infinite-duration games such as parity and mean-payoff games. We study the memory requirements for winning strategies of FCGs and certain associated infinite duration games. We exhibit a simple FCG that is not memoryless determined (this corrects a mistake in Memoryless determinacy of parity and mean payoff games: a simple proof by Bj⋯orklund, Sandberg, Vorobyov (2004) that claims that FCGs for which Y is closed under cyclic permutations are memoryless determined). We show that θ (n)! memory (where n is the number of nodes in the graph), which is always sufficient, may be necessary to win some FCGs. On the other hand, we identify easy to check conditions on Y (i.e., Y is closed under cyclic permutations, and both Y and its complement are closed under concatenation) that are sufficient to ensure that the corresponding FCGs and their associated infinite duration games are memoryless determined. We demonstrate that many games considered in the literature, such as mean-payoff, parity, energy, etc., satisfy these conditions. On the complexity side, we show (for efficiently computable Y) that while solving FCGs is in PSPACE, solving some families of FCGs is PSPACE-hard. },
author = {Aminof, Benjamin and Rubin, Sasha},
booktitle = {Electronic Proceedings in Theoretical Computer Science, EPTCS},
location = {Grenoble, France},
pages = {83 -- 90},
publisher = {Open Publishing Association},
title = {{First cycle games}},
doi = {10.4204/EPTCS.146.11},
volume = {146},
year = {2014},
}
@article{535,
abstract = {Energy games belong to a class of turn-based two-player infinite-duration games played on a weighted directed graph. It is one of the rare and intriguing combinatorial problems that lie in NP∩co-NP, but are not known to be in P. The existence of polynomial-time algorithms has been a major open problem for decades and apart from pseudopolynomial algorithms there is no algorithm that solves any non-trivial subclass in polynomial time. In this paper, we give several results based on the weight structures of the graph. First, we identify a notion of penalty and present a polynomial-time algorithm when the penalty is large. Our algorithm is the first polynomial-time algorithm on a large class of weighted graphs. It includes several worst-case instances on which previous algorithms, such as value iteration and random facet algorithms, require at least sub-exponential time. Our main technique is developing the first non-trivial approximation algorithm and showing how to convert it to an exact algorithm. Moreover, we show that in a practical case in verification where weights are clustered around a constant number of values, the energy game problem can be solved in polynomial time. We also show that the problem is still as hard as in general when the clique-width is bounded or the graph is strongly ergodic, suggesting that restricting the graph structure does not necessarily help.},
author = {Chatterjee, Krishnendu and Henzinger, Monika and Krinninger, Sebastian and Nanongkai, Danupon},
journal = {Algorithmica},
number = {3},
pages = {457 -- 492},
publisher = {Springer},
title = {{Polynomial time algorithms for energy games with special weight structures}},
doi = {10.1007/s00453-013-9843-7},
volume = {70},
year = {2014},
}
@article{537,
abstract = {Transgenerational effects are broader than only parental relationships. Despite mounting evidence that multigenerational effects alter phenotypic and life-history traits, our understanding of how they combine to determine fitness is not well developed because of the added complexity necessary to study them. Here, we derive a quantitative genetic model of adaptation to an extraordinary new environment by an additive genetic component, phenotypic plasticity, maternal and grandmaternal effects. We show how, at equilibrium, negative maternal and negative grandmaternal effects maximize expected population mean fitness. We define negative transgenerational effects as those that have a negative effect on trait expression in the subsequent generation, that is, they slow, or potentially reverse, the expected evolutionary dynamic. When maternal effects are positive, negative grandmaternal effects are preferred. As expected under Mendelian inheritance, the grandmaternal effects have a lower impact on fitness than the maternal effects, but this dual inheritance model predicts a more complex relationship between maternal and grandmaternal effects to constrain phenotypic variance and so maximize expected population mean fitness in the offspring.},
author = {Prizak, Roshan and Ezard, Thomas and Hoyle, Rebecca},
journal = {Ecology and Evolution},
number = {15},
pages = {3139 -- 3145},
publisher = {Wiley-Blackwell},
title = {{Fitness consequences of maternal and grandmaternal effects}},
doi = {10.1002/ece3.1150},
volume = {4},
year = {2014},
}