bluuebunny/crossref_metadata_2025_split huggingface dataset:
2-arachidonoylglycerol signaling impairs short-term fear extinction
Authors: Hartley N D , Gunduz-Cinar O , Halladay L , Bukalo O , Holmes A , Patel S 
Published: March 2016

AbstractImpairments in fear extinction are thought to be central to the psychopathology of posttraumatic stress disorder, and endocannabinoid (eCB) signaling has been strongly implicated in extinction learning. Here we utilized the monoacylglycerol lipase inhibitor JZL184 to selectively augment brain 2-AG levels combined with an auditory cue fear-conditioning paradigm to test the hypothesis that 2-AG-mediated eCB signaling modulates short-term fear extinction learning in mice. We show that systemic JZL184 impairs short-term extinction learning in a CB1 receptor-dependent manner without affecting non-specific freezing behavior or the acquisition of conditioned fear. This effect was also observed in over-conditioned mice environmentally manipulated to re-acquire fear extinction. Cumulatively, the effects of JZL184 appear to be partly due to augmentation of 2-AG signaling in the basolateral nucleus of the amygdala (BLA), as direct microinfusion of JZL184 into the BLA produced similar results. Moreover, we elucidate a short ~3-day temporal window during which 2-AG augmentation impairs extinction behavior, suggesting a preferential role for 2-AG-mediated eCB signaling in the modulation of short-term behavioral sequelae to acute traumatic stress exposure.
Co-occurrence of analogous enzymes determines evolution of a novel (βα)8-isomerase sub-family after non-conserved mutations in flexible loop
Authors: Verduzco-Castro Ernesto A. , Michalska Karolina , Endres Michael , Juárez-Vazquez Ana L. , Noda-García Lianet , Chang Changsoo , Henry Christopher S. , Babnigg Gyorgy , Joachimiak Andrzej , Barona-Gómez Francisco 
Published: March 2016

We investigate the evolution of co-occurring analogous enzymes involved in L-tryptophan and L-histidine biosynthesis in Actinobacteria. Phylogenetic analysis of trpF homologues, a missing gene in certain clades of this lineage whose absence is complemented by a dual-substrate HisA homologue, termed PriA, found that they fall into three categories: (i) trpF-1, an L-tryptophan biosynthetic gene horizontally acquired by certain Corynebacterium species; (ii) trpF-2, a paralogue known to be involved in synthesizing a pyrrolopyrrole moiety and (iii) trpF-3, a variable non-conserved orthologue of trpF-1. We previously investigated the effect of trpF-1 upon the evolution of PriA substrate specificity, but nothing is known about the relationship between trpF-3 and priA. After in vitro steady-state enzyme kinetics we found that trpF-3 encodes a phosphoribosyl anthranilate isomerase. However, mutation of this gene in Streptomyces sviceus did not lead to auxothrophy, as expected from the biosynthetic role of trpF-1. Biochemical characterization of a dozen co-occurring TrpF-2 or TrpF-3, with PriA homologues, explained the prototrophic phenotype, and unveiled an enzyme activity trade-off between TrpF and PriA. X-ray structural analysis suggests that the function of these PriA homologues is mediated by non-conserved mutations in the flexible L5 loop, which may be responsible for different substrate affinities. Thus, the PriA homologues that co-occur with TrpF-3 represent a novel enzyme family, termed PriB, which evolved in response to PRA isomerase activity. The characterization of co-occurring enzymes provides insights into the influence of functional redundancy on the evolution of enzyme function, which could be useful for enzyme functional annotation.
Compact filtering slot antenna with frequency agility for Wi‐Fi/LTE mobile applications
Authors: Soltanpour M. , Fakharian M.M. 
Published: March 2016

A reconfigurable filtering slot antenna (filtesnna) for Wi‐Fi/LTE mobile systems is proposed. The reconfigurable filtesnna is based on integrating a switchable bandpass filter inside the feeding line of a slot antenna structure. This design is achieved by using an open/short‐ended inter‐digital E‐shaped patch via two integrated pin diodes within its structure. The proposed filtesnna has a small size of 0.25λ0 × 0.1λ0 (λ0 is the free‐space wavelength at 2.1 GHz). The filtesnna is designed at centre frequencies of 2.1/2.4 GHz with measured 10 dB return loss impedance bandwidths from 2.03 to 2.17 GHz or 2.37 to 2.51 GHz when the diodes are ON or OFF, respectively. A prototype of the reconfigurable filtesnna has been fabricated and measured. A good adaptation is acquired between the simulated and the measured results.
Leakage current generation in view of circuit topology of non‐isolated full‐bridge neutral point clamped grid‐tied photovoltaic inverters
Authors: Anandababu Chakravartula , Fernandes Baylon G. 
Published: March 2016

Full‐bridge neutral point clamped (NPC) non‐isolated inverter topologies are used to mitigate leakage current at switching frequency due to non‐ideal circuit parameters. Among these topologies, this current is the highest in optimised non‐isolated inverter (oH5I) despite lowest switch count. This study analyses the limitations of oH5I in mitigating the leakage current by considering the junction capacitance of switches into account. This analysis elucidates the dependency of common‐mode voltage (CMV) characteristics on circuit topology and dead time requirement. In order to ascertain this fact, a novel non‐isolated full‐bridge NPC inverter (NIFB‐NPCI) is proposed. The CMV characteristics of this inverter are analysed during mode transitions and compared with that in oH5I. A 1 kVA unified prototype circuit of these inverters is designed and fabricated for experimental validation. The circuit topology and dead time requirement of oH5I cause a spike in CMV during each mode transition. However, these limitations are addressed in the proposed inverter, and CMV is maintained at a constant value. Hence, NIFB‐NPCI evinces lower leakage current at switching frequency than oH5I. Therefore, the effect of topological limitation of full‐bridge NPC non‐isolated inverters on leakage current mitigation is validated.
The interdisciplinarity of critical discourse studies research
Authors: Unger Johann W 
Published: March 2016

AbstractInterdisciplinarity has been a core tenet of critical discourse studies—a group of approaches to the analysis of texts in their social contexts—since its inception, in what may be seen as a reaction against the sometimes staid and rigid disciplinary boundaries of linguistics and other disciplines. Interdisciplinarity has also been seen as necessarily accompanying analyses of complex social problems such as racism, sexism or other forms of discrimination and social domination. The concept has been multiply re-examined, challenged and reaffirmed by critical discourse scholars (for instance, in Weiss and Wodak, 2003), and the present article continues this work by mapping out the present-day dimensions of interdisciplinarity in different approaches to critical discourse studies. It also attempts to juxtapose these various disciplinary developments, and consider whether interdisciplinarity in and of itself has come to be taken for granted. Finally, it raises questions about whether the move away from an emphasis on the analysis of social wrongs within some of the newer approaches to critical discourse studies may in time lead to a disciplinary schism, or whether the increasingly disciplinary nature of critical discourse studies itself may have become a problem. This article forms part of an ongoing thematic collection dedicated to the concept of interdisciplinarity.
Gendered performances in sport: an embodied approach
Authors: Wellard Ian 
Published: March 2016

AbstractDespite significant advances in recent years, gender inequalities remain apparent within the context of sport participation and engagement. One of the problems, however, when addressing gender issues in sport is the continued assumption by many sport practitioners that the experiences of women and men will always be different because of perceived physiological characteristics. Adopting a focus based solely on perceived gendered differences often overlooks the importance of recognizing individual experience and the prevailing social influences that impact on participation such as age, class, race and ability. An embodied approach, as well as seeking to move beyond mind/body dualisms, incorporates the physiological with the social and psychological. Therefore, it is suggested that, although considerations of gender remain important, they need to be interpreted alongside other interconnecting and influential (at varying times and occasions) social and physical factors. It is argued that taking the body as a starting point opens up more possibilities to manoeuvre through the mine field that is gender and sport participation. The appeal of an embodied approach to the study of gender and sport is in its accommodation of a wider multidisciplinary lens. Particularly, by acknowledging the subjective, corporeal, lived experiences of sport engagement, an embodied approach offers a more flexible starting point to negotiate the theoretical and methodological challenges created by restrictive discourses of difference.
Mushrooms use convectively created airflows to disperse their spores
Authors: Dressaire Emilie , Yamada Lisa , Song Boya , Roper Marcus 
Published: March 2016

Significance
Mushroom spore dispersal is usually described as a two-phase process: active ejection of spores clear of the gill surface by surface tension catapults, followed by a passive phase in which the spores are carried by whatever winds are present beneath the mushroom cap. Here, we show that control extends into the second phase of dispersal: water vapor loss creates slow airflows that carry spores out from under the mushroom cap and potentially tens of centimeters into the air. In addition to clarifying why mushrooms have such high water needs, and providing a mechanism by which spore dispersal can occur even in a low-wind environment, our work shows that the physics of apparently passive dispersal may be under organismal control.
Redox-coupled proton transfer mechanism in nitrite reductase revealed by femtosecond crystallography
Authors: Fukuda Yohta , Tse Ka Man , Nakane Takanori , Nakatsu Toru , Suzuki Mamoru , Sugahara Michihiro , Inoue Shigeyuki , Masuda Tetsuya , Yumoto Fumiaki , Matsugaki Naohiro , Nango Eriko , Tono Kensuke , Joti Yasumasa , Kameshima Takashi , Song Changyong , Hatsui Takaki , Yabashi Makina , Nureki Osamu , Murphy Michael E. P. , Inoue Tsuyoshi , Iwata So , Mizohata Eiichi 
Published: March 2016

Significance
Copper nitrite reductase (CuNiR) is involved in denitrification of the nitrogen cycle. Synchrotron X-rays rapidly reduce copper sites and decompose the substrate complex structure, which has made crystallographic studies of CuNiR difficult. Using femtosecond X-ray free electron lasers, we determined intact structures of CuNiR with and without nitrite. Based on the obtained structures, we proposed a redox-coupled proton switch model, which provides an explanation for proton-coupled electron transfer (PCET) in CuNiR. PCET is widely distributed through biogenic processes including respiratory and photosynthetic systems and is highly expected to be incorporated into bioinspired molecular devices. Our study also establishes the foundation for future studies on PCET in other systems.
Novel genomic island modifies DNA with 7-deazaguanine derivatives
Authors: Thiaville Jennifer J. , Kellner Stefanie M. , Yuan Yifeng , Hutinet Geoffrey , Thiaville Patrick C. , Jumpathong Watthanachai , Mohapatra Susovan , Brochier-Armanet Celine , Letarov Andrey V. , Hillebrand Roman , Malik Chanchal K. , Rizzo Carmelo J. , Dedon Peter C. , de Crécy-Lagard Valérie 
Published: March 2016

Significance
The discovery of a novel modification system that inserts 7-deazaguanine derivatives in DNA, modifications thought until now to occur only in RNA, is an excellent illustration of the power of biological evolution to alter the ultimate function not only of the distinct proteins but also of entire metabolic pathways. The extensive lateral transfer of the gene cluster responsible for this modification highlights its significance as a previously unrecognized foreign DNA defense system that bacteria and phages use to protect their genomes. The characterization of these DNA modification pathways also opens the door to novel tools to manipulate nucleic acids.
Structural basis for DNA cleavage by the potent antiproliferative agent (–)-lomaiviticin A
Authors: Woo Christina M. , Li Zhenwu , Paulson Eric K. , Herzon Seth B. 
Published: March 2016

SignificanceDNA is a canonical target for chemotherapeutic intervention, and several DNA-reactive natural products are in clinical use. An understanding of the mode of DNA binding of these agents is an essential component of translational development. Here we show that (–)-lomaiviticin A (1), a naturally occurring DNA cleavage agent undergoing preclinical evaluation, binds DNA by an unusual mode of association involving insertion of two complex polycyclic arene fragments into the duplex, with concomitant disruption of base pairing. Additionally, our studies suggest that DNA binding activates the DNA cleavage activity of 1. This study provides a structural basis for the activity of 1 and for the development of synthetic DNA-damaging agents capable of recapitulating this mechanism of association and activation.
Long-ranged contributions to solvation free energies from theory and short-ranged models
Authors: Remsing Richard C. , Liu Shule , Weeks John D. 
Published: March 2016

Significance
Many important biological and industrial processes, ranging from protein folding and ligand binding to self-assembly of materials at interfaces, take place in solution and are mediated by driving forces rooted in solvation. However, conceptual and computational difficulties arising from long-ranged Coulomb interactions still present a challenge to current approaches. Here we present a framework to determine very accurately the long-ranged contributions to solvation free energies in charged and polar systems from models with only short-ranged, local interactions. We examine a variety of ubiquitous solvation processes, including hydrophobic and ionic hydration, as well as colloidal overcharging. The theory additionally suggests ways to improve density functional theories of solvation by providing insights into commonly used approximations.
High-throughput small molecule screen identifies inhibitors of aberrant chromatin accessibility
Authors: Pattenden Samantha G. , Simon Jeremy M. , Wali Aminah , Jayakody Chatura N. , Troutman Jacob , McFadden Andrew W. , Wooten Joshua , Wood Cameron C. , Frye Stephen V. , Janzen William P. , Davis Ian J. 
Published: March 2016

Significance
Transcriptional regulators lacking enzymatic activity or binding pockets with targetable molecular features have typically been considered “undruggable,” and a reductionist approach based on identification of their molecular targets has largely failed. We have demonstrated that the Ewing sarcoma chimeric transcription factor, EWSR1-FLI1, maintains accessible chromatin at disease-specific regions. We adapted formaldehyde-assisted isolation of regulatory elements (FAIRE), an assay for accessible chromatin, to screen an epigenetically targeted small molecule library for compounds that reverse the disease-associated signature. This approach can be applied broadly for discovery of chromatin-based developmental therapeutics and offers significant advantages because it does not require the selection of a single molecular target. Using this approach, we identified a specific class of compounds with therapeutic potential.
Type VI secretion system sheaths as nanoparticles for antigen display
Authors: Del Tordello Elena , Danilchanka Olga , McCluskey Andrew J. , Mekalanos John J. 
Published: March 2016

SignificanceCritical aspects that limit use of nanoparticles as vaccine delivery systems include the technical difficulty of preparing particles under conditions that allow controlled protein loading and folding. Biologic nanoparticles offer advantages over chemically derived particles that require harsh organic solvents for preparation. Here, we demonstrate that the multimeric sheath structure of the bacterial type 6 secretion system (T6SS) can be exploited to generate particles that display on their surface many copies of specific proteins of interest. T6SS sheaths represent a functional vaccine delivery system with remarkable flexibility due to the ability to biochemically modify these structures to expand or enhance potential immunogenicity.
Tungsten isotopic constraints on the age and origin of chondrules
Authors: Budde Gerrit , Kleine Thorsten , Kruijer Thomas S. , Burkhardt Christoph , Metzler Knut 
Published: March 2016

Significance
The origin of chondrules—millimeter-sized silicate-rich spherules that dominate the most primitive meteorites, the chondrites—is a long-standing puzzle in cosmochemistry. Here, we present isotopic evidence that chondrules and matrix from the Allende chondrite contain different and complementary proportions of presolar matter, indicating that chondrules and matrix formed together from a single reservoir of solar nebula dust. This finding rules out formation of chondrules in protoplanetary impacts and demonstrates that chondrules are the product of localized melting events in the solar protoplanetary disk. Moreover, the isotopic complementarity of chondrules and matrix requires that chondrules formed in a narrow time interval and were rapidly accreted to a parent body, implying that chondrule formation was a critical step toward forming planetesimals.
Measures with locally finite support and spectrum
Authors: Meyer Yves F. 
Published: March 2016

SignificanceAn important problem in harmonic analysis is solved in this article: Is the Poisson summation formula unique or does it belong to a wider class? The latter is true. The method that is used to prove this statement is surprising. Our new Poisson’s formulas were hidden inside an old and almost forgotten paper published in 1959 by A. P. Guinand. The role of number theory in this issue is fascinating.
Functional requirements of AID’s higher order structures and their interaction with RNA-binding proteins
Authors: Mondal Samiran , Begum Nasim A. , Hu Wenjun , Honjo Tasuku 
Published: March 2016

Significance
This paper demonstrates that activation-induced cytidine deaminase (AID), an essential enzyme in antigen-induced antibody diversification, forms distinct ribonucleoprotein complexes depending on its structural states: namely monomers or dimers. The identified RNA-binding proteins are required for the function of AID: namely DNA cleavage or recombination. In addition, the complex formation between AID and heterogeneous nuclear ribonucleoproteins (hnRNPs) is RNA-dependent.
Aspects of interrogative use in near-native French
Authors: Donaldson Bryan 
Published: March 2016

Abstract
This paper reports on interrogative (question) use in the informal spontaneous speech of near-native second-language French speakers. Interrogatives present considerable variation in French, and choices of interrogative form depend on semantics, communicative function, and register. Using a corpus of spontaneous conversations between near-native (NNSs) and native speakers (NSs), the inventory of interrogatives used is described; A detailed examination is then given of the question marker est-ce que (“is it that”), a candidate for overuse in L2 French (Zwanziger 2008, p. 91). The results, from 825 occurrences of interrogative structures, reveal that the NNSs possess extremely similar inventories of interrogative forms to their NS interlocutors and that their interrogative choices are both communicatively and socio-stylistically appropriate. What appears quantitatively as overuse of est-ce que by two NNSs is, from a communicative point of view, entirely felicitous: Like NSs, the NNSs reserve est-ce que for several marked interrogative contexts. The results suggest that the NNSs successfully integrate syntactic, semantic, communicative, and sociolinguistic information in spontaneous conversation.
Egalitarians, sufficientarians, and mathematicians: a critical notice of Harry Frankfurt’s On Inequality
Authors: Rondel David 
Published: March 2016

AbstractThis critical notice provides an overview of Harry Frankfurt’s On Inequality and assesses whether Frankfurt is right to argue that equality is merely formal and empty. I counter-argue that egalitarianism, properly tweaked and circumscribed, can be defended against Frankfurt’s repudiation. After surveying the main arguments in Frankfurt’s book, I argue that whatever plausibility the ‘doctrine of sufficiency’ defended by Frankfurt may have, it does not strike a fatal blow against egalitarianism. There is nothing in egalitarianism that forbids acceptance of the moral platitude expressed in sufficientarianism's positive thesis, (viz., it is morally important that everyone have enough). Nor is there anything in egalitarianism as such that makes it impossible to recognize the banal truth that there are many important things besides equality, and that many dimensions of human affairs are improperly appraised from a relational or comparative point of view. The fact that a relational or comparative point of view is sometimes out of place, however, surely does not mean that it always is. I conclude with the suggestion that egalitarianism is most compelling when it is understood as a normative conception of social relations (rather than, as Frankfurt seems to assume throughout his book, a thesis about the equal distribution of something) and thus presides over precisely those aspects of human affairs for which that relational or comparative point of view is germane.
Ypq3p-dependent histidine uptake by the vacuolar membrane vesicles of Saccharomyces cerevisiae
Authors: Manabe Kunio , Kawano-Kawada Miyuki , Ikeda Koichi , Sekito Takayuki , Kakinuma Yoshimi 
Published: March 2016

Abstract
The vacuolar membrane proteins Ypq1p, Ypq2p, and Ypq3p of Saccharomyces cerevisiae are known as the members of the PQ-loop protein family. We found that the ATP-dependent uptake activities of arginine and histidine by the vacuolar membrane vesicles were decreased by ypq2Δ and ypq3Δ mutations, respectively. YPQ1 and AVT1, which are involved in the vacuolar uptake of lysine/arginine and histidine, respectively, were deleted in addition to ypq2Δ and ypq3Δ. The vacuolar membrane vesicles isolated from the resulting quadruple deletion mutant ypq1Δypq2Δypq3Δavt1Δ completely lost the uptake activity of basic amino acids, and that of histidine, but not lysine and arginine, was evidently enhanced by overexpressing YPQ3 in the mutant. These results suggest that Ypq3p is specifically involved in the vacuolar uptake of histidine in S. cerevisiae. The cellular level of Ypq3p-HA3 was enhanced by depletion of histidine from culture medium, suggesting that it is regulated by the substrate.