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Practical implementation of next-generation Li-ion battery chemistries is to a large extent obstructed by the absence of an electrolyte that is capable of simultaneously supporting reversible electrochemical reactions at two extreme electrochemical potentials—above 4.5 V at the positive electrode and near 0 V vs. Li at the negative electrode. Electrolytes based on carbonate esters have been reliable in satisfying state-of-the-art Li-ion battery (LIB) chemistries below 4.4 V), releasing CO2. In this work, we explore a carbonate-free electrolyte system based on a single sulfone solvent, in which a newly discovered synergy between solvent and salt simultaneously addresses the interfacial requirements of both graphitic anode and high-voltage cathode (LiNi0.5Mn1.5O4 (LNMO)). Experimental measurements, quantum chemistry (QC) calculations, and molecular dynamics simulations reveal the system's fast ion conduction, stability over a wide temperature range, and non-flammability. At the anode, a LiF-rich interphase generated by early-onset reduction of the salt anion effectively suppresses solvent co-intercalation and subsequent graphite exfoliation, enabling unprecedented and highly reversible graphite cycling in a pure sulfone system. Under oxidative conditions, QC calculations predict that high salt concentration promotes complex/aggregate formation which slow the decomposition of sulfolane and leads to polymerizable rather than gaseous products—a fundamental improvement over carbonate solvents. These predictions are corroborated by X-ray photoelectron spectroscopy (XPS), cryogenic-transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS) experiments, which revealed the presence of a thin, conformal, sulfur-based cathode electrolyte interphase (CEI). Together, the functional interphases (SEI/CEI) generated by this electrolyte system supported long term operation of a high-voltage (4.85 V) LNMO/graphite full cell, which retained ∼70% of its original first-cycle discharge capacity after the 1000th cycle. Based on these results, this new carbonate-free electrolyte system, supported by the mechanistic understanding of its behavior, presents a promising new direction toward unlocking the potential of next generation Li-ion battery electrodes.

Nanostructured block copolymer electrolytes have the potential to enable solid-state batteries with lithium metal anodes. We present complete continuum characterization of ion transport in a lamellar polystyrene-b-poly(ethylene oxide) copolymer/lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) electrolyte as a function of salt concentration. Electrochemical measurements are used to determine the Stefan-Maxwell salt diffusion coefficients [Formula: see text], [Formula: see text], and [Formula: see text]. Individual self-diffusion coefficients of the lithium- and TFSI-containing species were measured by pulsed-field gradient NMR (PFG-NMR). The NMR data indicate that salt diffusion is locally anisotropic, and this enables determination of a diffusion coefficient parallel to the lamellae, D∥, and a diffusion coefficient through defects in the lamellae, D⊥. We quantify anisotropic diffusion by defining an NMR morphology factor and demonstrate that it is correlated to defect density seen by transmission electron microscopy. We find agreement between the electrochemically determined Stefan-Maxwell diffusion coefficients and the diffusion coefficient D⊥ determined by PFG-NMR. Our work indicates that the performance of nanostructured block copolymer electrolytes in batteries is strongly influenced by ion transport through defects.

We present a computational model of the acquisition ofGerman case that is evaluated against empirical data obtainedfrom naturalistic speech. The model substitutes nouns intoexisting contexts, and proceeds through a number of stages thatreflect increasing knowledge on the part of a child, both of thedeterminer-noun sequences that are legal in German, and of thedeterminer-noun sequences that are appropriate in specificsentential contexts (cases). The model provides a naturalaccount of gender and case errors, the two most common errortypes produced by children, and shows the highest error ratesin dative contexts and lowest error rates in nominative contexts,as is true of children learning German. However, the model’serror rates in the early stages are considerably higher than thoseshown by children, suggesting that children possess a fairlysophisticated representation of how lexical contexts assign casefrom a relatively early age.

Recent work has derived the optimal policy for two-alternative value-based decisions, in which decision-makers compare the subjective expected reward of two alternatives. Under specific task assumptions --- such as linear utility, linear cost of time and constant processing noise --- the optimal policy is implemented by a diffusion process in which parallel decision thresholds collapse over time as a function of prior knowledge about average reward across trials. This policy predicts that the decision dynamics of each trial are dominated by the difference in value between alternatives and are insensitive to the magnitude of the alternatives (i.e., their summed values). This prediction clashes with empirical evidence showing magnitude-sensitivity even in the case of equal alternatives, and with ecologically plausible accounts of decision making. Previous work has shown that relaxing assumptions about linear utility or linear time cost can give rise to optimal magnitude-sensitive policies. Here we question the assumption of constant processing noise, in favour of input-dependent noise. The neurally plausible assumption of input-dependent noise during evidence accumulation has received strong support from previous experimental and modelling work. We show that including input-dependent noise in the evidence accumulation process results in a magnitude-sensitive optimal policy for value-based decision-making, even in the case of a linear utility function and a linear cost of time, for both single (i.e., isolated) choices and sequences of choices in which decision-makers maximise reward rate. Compared to explanations that rely on non-linear utility functions and/or non-linear cost of time, our proposed account of magnitude-sensitive optimal decision-making provides a parsimonious explanation that bridges the gap between various task assumptions and between various types of decision making.

Genetic variations affect behavior and cause disease but understanding how these variants drive complex traits is still an open question. A common approach is to link the genetic variants to intermediate molecular phenotypes such as the transcriptome using RNA-sequencing (RNA-seq). Paradoxically, these variants between the samples are usually ignored at the beginning of RNA-seq analyses of many model organisms. This can skew the transcriptome estimates that are used later for downstream analyses, such as expression quantitative trait locus (eQTL) detection. Here, we assessed the impact of reference-based analysis on the transcriptome and eQTLs in a widely-used mouse genetic population: the BXD panel of recombinant inbred lines. We highlight existing reference bias in the transcriptome data analysis and propose practical solutions which combine available genetic variants, genotypes, and genome reference sequence. The use of custom BXD line references improved downstream analysis compared to classical genome reference. These insights would likely benefit genetic studies with a transcriptomic component and demonstrate that genome references need to be reassessed and improved.

In this note, we give a new proof of a result of Matthew Dyer stating that in an arbitrary Coxeter group W, every pair t,t' of distinct reflections lie in a unique maximal dihedral reflection subgroup of W. Our proof only relies on the combinatorics of words, in particular we do not use root systems at all. As an application, we deduce a new proof of a recent result of Delucchi-Paolini-Salvetti, stating that the poset [1,c]_T of generalized noncrossing partitions in any Coxeter group of rank 3 is a lattice. We achieve this by showing the more general statement that any interval of length 3 in the absolute order on an arbitrary Coxeter group is a lattice. This implies that the interval group attached to any interval [1,w]_T where w is an element of an arbitrary Coxeter group with \ell _T(w)=3 is a quasi-Garside group. [ABSTRACT FROM AUTHOR]

In eukaryotes, RNA is synthesised in the nucleus, spliced, and exported to the cytoplasm where it is translated and finally degraded. Any of these steps could be subject to temporal regulation during the circadian cycle, resulting in daily fluctuations of RNA accumulation and affecting the distribution of transcripts in different subcellular compartments. Our study analysed the nuclear and cytoplasmic, poly(A) and total transcriptomes of mouse livers collected over the course of a day. These data provide a genome-wide temporal inventory of enrichment in subcellular RNA, and revealed specific signatures of splicing, nuclear export and cytoplasmic mRNA stability related to transcript and gene lengths. Combined with a mathematical model describing rhythmic RNA profiles, we could test the rhythmicity of export rates and cytoplasmic degradation rates of approximately 1400 genes. With nuclear export times usually much shorter than cytoplasmic half-lives, we found that nuclear export contributes to the modulation and generation of rhythmic profiles of 10% of the cycling nuclear mRNAs. This study contributes to a better understanding of the dynamic regulation of the transcriptome during the day-night cycle.

Why games? How could anyone consider action gamesas experimental paradigms for Cognitive Science? In 1973,as one of three strategies he proposed for advancing Cogni-tive Science, Allen Newell exhorted us to “accept a singlecomplex task and do all of it.” More specifically, he told usthat rather than taking an “experimental psychology as usualapproach” that, we should “focus on a series of experimentaland theoretical studies around a single complex task” so as todemonstrate that our theories of human cognition were pow-erful enough to explain, “a genuine slab of human behavior”with the studies fitting into a detailed theoretical picture. Ac-tion games represent the type of experimental paradigms thatNewell was advocating and the current state of programmingexpertise and laboratory equipment, along with the emer-gence of Big Data (Griffiths, 2015) and Naturally OccurringData Sets (NODS, Goldstone & Lupyan, 2016), provide thetechnologies and data needed to realize his vision. ActionGames enable us to escape from our field’s regrettable fo-cus on novice performance to develop theories that accountfor the full range of expertise through a twin focus on ex-pertise sampling (across individuals) and longitudinal studies(within individuals) of simple and complex tasks.This Symposium is inspired by the recent Action Gamesas Experimental Paradigms for Cognitive Science (Game-XP), issue of Topics in Cognitive Science (topiCS), April2017. It includes late-breaking work from some of the re-searchers represented in that topic as well as new work bynew researchers.

The positive relationship between spatial ability andmathematical skills is a classical result in developmental andcognitive psychology. Given this correlational relationship,researchers have tried to establish whether spatial training canincrease mathematical ability. Such research has providedmixed results. In this study, we analysed the effects of twotypes of spatial training and handedness on primary schoolchildren’s arithmetical ability. The participants were pre-testedon a test of arithmetic and assigned to one of three groups: (a)one hour of mental rotation and translation training, (b) onehour of mental translation training only, or (c) a no-contactgroup. The results showed no significant difference betweentraining groups and a significant interaction between traininggroup and category of handedness. Interestingly, onlyextremely right-handed children in the mental rotation andtranslation group seemed to benefit from the training. Theseoutcomes suggest that any spatial training needs to includemental rotation activities to be effective, and that therelationship between spatial training and achievementmathematics appears to be moderated by handedness.

Implementing interventions that are supposed to enhance students’general learning skill and overall cognitive ability is still acommon practice in education. The basic idea on which thisapproach relies is that improving domain-general skills providesbenefits for a broad range of domain-specific areas, such asacademic disciplines. Thus, it is assumed that there is far transfer –i.e., the generalization of a set of skills between domains looselyrelated to each other. In recent years, chess instruction, musicinstruction, and working memory training have been claimed to beable to train domain-general abilities (e.g., fluidreasoning/intelligence) which, in turn, generalize to other cognitiveand academic skills (e.g., mathematics). We tested these claims inthe population of healthy children via meta-analysis. The resultsshowed small to moderate overall far-transfer effects in all theoutcome measures of the three meta-analyses. However, the effectsizes were inversely related to the design quality (e.g., presence ofactive control groups), which casts doubts on the effectiveness ofthe three activities. We discuss the theoretical and practicalimplications of these findings for education and expertise andextend the debate to another type of training, video games training.

Since the Last Glacial Maximum (LGM; end ca. 19 000 cal BP) central European plant communities have been shaped by changing climatic and anthropogenic disturbances. Understanding long-term ecosystem reorganizations in response to past environmental changes is crucial to draw conclusions about the impact of future climate change. So far, it has been difficult to address the post-deglaciation timing and ecosystem dynamics due to a lack of well-dated and continuous sediment sequences covering the entire period after the LGM. Here, we present a new paleoecological study with exceptional chronological time control using pollen, spores and microscopic charcoal from Moossee (Swiss Plateau, 521 m a.s.l.) to reconstruct the vegetation and fire history over the last ca. 19 000 years. After lake formation in response to deglaciation, five major pollen-inferred ecosystem rearrangements occurred at ca. 18 800 cal BP (establishment of steppe tundra), 16 000 cal BP (spread of shrub tundra), 14 600 cal BP (expansion of boreal forests), 11 600 cal BP (establishment of the first temperate deciduous tree stands composed of, e.g., Quercus, Ulmus, Alnus) and 8200 cal BP (first occurrence of mesophilous Fagus sylvatica trees). These vegetation shifts were caused by climate changes at ca. 19 000, 16 000, 14 700, 11 700 and 8200 cal BP. Vegetation responses occurred with no apparent time lag to climate change when the mutual chronological uncertainties are considered. This finding is in agreement with further evidence from southern and central Europe and might be explained by the proximity to the refugia of boreal and temperate trees ( km) and rapid species spreads. Our palynological record sets the beginning of millennial-scale land use with periodically increased fire and agricultural activities of the Neolithic period at ca. 7000 cal BP. Subsequently, humans rather than climate triggered changes in vegetation composition and structure. We conclude that Fagus sylvatica forests were resilient to long-term anthropogenic and climatic impacts of the Mid and the Late Holocene. However, future climate warming and in particular declining moisture availability may cause unprecedented reorganizations of central European beech-dominated forest ecosystems.

Adrenal aldosterone production is regulated by plasma angiotensin and potassium levels. Here the authors report that the neuropeptide substance P stimulates aldosterone production via neurokinin type 1 receptors (NK1R), and report a proof-of-concept placebo controlled clinical trial showing that a NK1R antagonist decreases aldosterone levels.