bluuebunny/crossref_metadata_2025_split huggingface dataset:
Age‐related neurochemical changes in the rhesus macaque cochlear nucleus
Authors: Gray Daniel T. , Engle James R. , Recanzone Gregg H. 
Published: October 2013

ABSTRACTNeurochemical changes in the expression of various proteins within the central auditory system have been associated with natural aging. These changes may compensate in part for the loss of auditory sensitivity arising from two phenomena of the aging auditory system: cochlear histopathologies and increased excitability of central auditory neurons. Recent studies in the macaque monkey have revealed age‐related changes in the density of nicotinamide adenine dinucleotide phosphate (NADPH)‐diaphorase (NADPHd) and parvalbumin (PV)‐positive cells within the inferior colliculus and superior olivary complex. The cochlear nucleus (CN), which is the first central auditory nucleus, remains unstudied. Since the CN participates in the generation of the auditory brainstem response (ABR) and receives direct innervation from the cochlea, it serves as an ideal nucleus to compare the relationship between these neurochemical changes and the physiological and peripheral changes of the aging auditory system. We used stereological sampling to calculate the densities of NADPHd and PV reactive neurons within the three subdivisions of the CN in middle‐aged and aged rhesus macaques. Regression analyses of these values with ABR properties and cochlear histopathologies revealed relationships between these cell types and the changing characteristics of the aging auditory system. Our results indicate that NADPHd expression does change with age in a specific subdivision of the CN, but PV does not. Conversely, PV expression correlated with ABR amplitudes and outer hair cell loss in the cochlea, but NADPHd did not. These results indicate that NADPHd and PV may take part in distinct compensatory efforts of the aging auditory system. J. Comp. Neurol. 522:1527–1541, 2014. © 2013 Wiley Periodicals, Inc.
Cloning, phylogeny, and regional expression of a Y5 receptor mRNA in the brain of the sea lamprey (Petromyzon marinus)
Authors: Pérez‐Fernández Juan , Megías Manuel , Pombal Manuel A. 
Published: October 2013

ABSTRACTThe NPY receptors known as Y receptors are classified into three subfamilies, Y1, Y2, and Y5, and are involved in different physiological functions. The Y5 receptor is the only member of the Y5 subfamily, and it is present in all vertebrate groups, except for teleosts. Both molecular and pharmacological studies show that Y5 receptor is highly conserved during vertebrate evolution. Furthermore, this receptor is widely expressed in the mammalian brain, including the hypothalamus, where it is thought to take part in feeding and homeostasis regulation. Lampreys belong to the agnathan lineage, and they are thought to have branched out between the two whole‐genome duplications that occurred in vertebrates. Therefore, they are in a key position for studies on the evolution of gene families in vertebrates. Here we report the cloning, phylogeny, and brain expression pattern of the sea lamprey Y5 receptor. In phylogenetic studies, the lamprey Y5 receptor clusters in a basal position, together with Y5 receptors of other vertebrates. The mRNA of this receptor is broadly expressed in the lamprey brain, being especially abundant in hypothalamic areas. Its expression pattern is roughly similar to that reported for other vertebrates and parallels the expression pattern of the Y1 receptor subtype previously described by our group, as it occurs in mammals. Altogether, these results confirm that a Y5 receptor is present in lampreys, thus being highly conserved during the evolution of vertebrates, and suggest that it is involved in many brain functions, the only known exception being teleosts. J. Comp. Neurol. 522:1132–1154, 2014. © 2013 Wiley Periodicals, Inc.
Supernodal sparse Cholesky factorization on graphics processing units
Authors: Zou Dan , Dou Yong , Guo Song , Li Rongchun , Deng Lin 
Published: October 2013

SUMMARYSparse Cholesky factorization is the most computationally intensive component in solving large sparse linear systems and is the core algorithm of numerous scientific computing applications. A large number of sparse Cholesky factorization algorithms have previously emerged, exploiting architectural features for various computing platforms. The recent use of graphics processing units (GPUs) to accelerate structured parallel applications shows the potential to achieve significant acceleration relative to desktop performance. However, sparse Cholesky factorization has not been explored sufficiently because of the complexity involved in its efficient implementation and the concerns of low GPU utilization.In this paper, we present a new approach for sparse Cholesky factorization on GPUs. We present the organization of the sparse matrix supernode data structure for GPU and propose a queue‐based approach for the generation and scheduling of GPU tasks with dense linear algebraic operations. We also design a subtree‐based parallel method for multi‐GPU system. These approaches increase GPU utilization, thus resulting in substantial computational time reduction.Comparisons are made with the existing parallel solvers by using problems arising from practical applications. The experiment results show that the proposed approaches can substantially improve sparse Cholesky factorization performance on GPUs. Relative to a highly optimized parallel algorithm on a 12‐core node, we were able to obtain speedups in the range 1.59× to 2.31× by using one GPU and 1.80× to 3.21× by using two GPUs. Relative to a state‐of‐the‐art solver based on supernodal method for CPU‐GPU heterogeneous platform, we were able to obtain speedups in the range 1.52× to 2.30× by using one GPU and 2.15× to 2.76× by using two GPUs. Concurrency and Computation: Practice and Experience, 2013. Copyright © 2013 John Wiley & Sons, Ltd.
Spreading evidence models for trust propagation and aggregation in peer‐to‐peer networks
Authors: Tian Chunqi , Liu Xiaojian , Wang Lisheng , Zou Shihong 
Published: October 2013

SUMMARYTrust model plays an important role in ensuring the security of interactions in peer‐to‐peer (P2P) systems where a peer's trust evaluation depends on the interaction experience of its own and recommendation information from other peers. However, current trust models have limitations in solving not only the issues of time efficiency of direct interaction information but also the reliability and inconsistency of recommendation information. In this paper, we propose a Dempster‐Shafer evidence theory based trust model (ETTM) for P2P systems. The primary goal of ETTM is to be able to address information uncertainty and conflicting recommendation problems in a reputation‐based P2P environment. To make D‐S theory fits into P2P applications, we creatively revise the combination rules and achieve greatly improved results. To further improve the accuracy and performance, ETTM filters out noisy referrals if they are not compatible with most other evidence. In addition, a feedback‐based probabilistic searching algorithm is proposed to find the referrals with improved searching success rate and lowered network traffic. Experimental results show ETTM has a clear advantage in aggregating recommendation information. Moreover, ETTM is more robust and can generate a higher successful transaction rate than some other existing frameworks. Copyright © 2013 John Wiley & Sons, Ltd.
Modeling power and energy consumption of dense matrix factorizations on multicore processors
Authors: Alonso Pedro , Dolz Manuel F. , Mayo Rafael , Quintana‐Ortí Enrique S. 
Published: October 2013

SUMMARYIn this paper, we propose a model for the energy consumption of the concurrent execution of three key dense matrix factorizations, with task parallelism leveraged via the Symmetric Multi‐Processing Superscalar (SMPSs) runtime, on a multicore processor. Our model decomposes the power dissipation into the system, static and dynamic components, with the former two being estimated from basic, off‐line experiments. The dynamic power, on the other hand, requires significantly more care, and we introduce a contention‐aware model that accommodates for the variability of power consumption due to memory contention. Experimental results on an Intel Xeon E5504 processor with four cores, using an internal powermeter that samples the power drawn by the mainboard with a frequency of 1 KHz, show the reliability of the energy model for the Cholesky, LU, and QR factorizations on this platform. Copyright © 2013 John Wiley & Sons, Ltd.
Fine‐grained filtering to provide access control for data providing services within collaborative environments
Authors: Brown Kevin , Hayes Michael , Allison David , Capretz Miriam A.M. , Sazio Margaret , Mann Rupinder 
Published: October 2013

SummaryA data providing service (DPS) in service‐oriented architecture is tasked only with the retrieval of data that are annotated over a domain ontology. One particular motivating application of DPSs is their use within collaborative environments. An important characteristic for the enterprises of such a collaborative environment is the ability to employ data sharing with one another. A major concern in this situation is the protection of each enterprise's privacy while still permitting data sharing. One potential solution is to provide filtered data through access control. This work describes how to implement access control through fine‐grained filtering of DPS response messages; it is accomplished using a filtering ontology and relations between the domain ontology of DPS and the proposed filtering ontology. Therefore, enterprises can write enterprise‐specific access control policies referencing a common filtering ontology defined within a collaborative environment, enabling access control‐based data sharing within the environment. This work additionally illustrates the implementation of our general solution to data providing web services, interpreted by an eXtensible Access Control Markup Language‐based access control framework. The implementation is further evaluated in a case study of real world data, provided by a health research institute in London, Canada. Copyright © 2013 John Wiley & Sons, Ltd.
Cooperative Effects in the Detection of a Nitroaliphatic Liquid Explosive and an Explosive Taggant in the Vapor Phase by Calix[4]arene‐Based Carbazole‐Containing Conjugated Polymers
Authors: Barata Patrícia D. , Prata José V. 
Published: October 2013

AbstractTwo fluorescent molecular receptor based conjugated polymers were used in the detection of a nitroaliphatic liquid explosive (nitromethane) and an explosive taggant (2,3‐dimethyl‐2,3‐dinitrobutane) in the vapor phase. Results have shown that thin films of both polymers display remarkably high sensitivity and selectivity toward these analytes. Very fast, reproducible, and reversible responses were found. The unique behavior of these supramolecular host systems is ascribed to cooperativity effects developed between the calix[4]arene hosts and the phenylene ethynylene–carbazolylene main chains. The calix[4]arene hosts create a plethora of host–guest binding sites along the polymer backbone, either in their bowl‐shaped cavities or between the outer walls of the cavity, to direct guests to the area of the transduction centers (main chain) at which favorable photoinduced electron transfer to the guest molecules occurs and leads to the observed fluorescence quenching. The high tridimensional porous nature of the polymers imparted by the bis‐calixarene moieties concomitantly allows fast diffusion of guest molecules into the polymer thin films.
Comparison of Nanorod‐Structured Li[Ni0.54Co0.16Mn0.30]O2 with Conventional Cathode Materials for Li‐Ion Batteries
Authors: Noh Hyung‐Joo , Ju Jin Wook , Sun Yang‐Kook 
Published: October 2013

AbstractWe successfully synthesized a safe, high‐capacity cathode material specifically engineered for EV applications with a full concentration gradient (FCG) of Ni and Co ions at a fixed Mn content throughout the particles. The electrochemical and thermal properties of the FCG Li[Ni0.54Co0.16Mn0.30]O2 were evaluated and compared to those of conventional Li[Ni0.5Co0.2Mn0.3]O2 and Li[Ni1/3Co1/3Mn1/3]O2 materials. It was found that the FCG Li[Ni0.54Co0.16Mn0.30]O2 demonstrated a higher discharge capacity and a superior lithium intercalation stability compared to Li[Ni0.5Co0.2Mn0.3]O2 and Li[Ni1/3Co1/3Mn1/3]O2 over all of the tested voltage ranges. The results of electrochemical impedance spectroscopy and transition‐metal dissolution demonstrate that the microstructure of primary particle with rod‐shaped morphology plays an important role in reducing metal dissolution, which thereby decreases the charge transfer resistance as a result of stabilization of the host structure.
Photocatalytic Hydrogen Production Using Models of the Iron–Iron Hydrogenase Active Site Dispersed in Micellar Solution
Authors: Orain Christophe , Quentel François , Gloaguen Frederic 
Published: October 2013

AbstractIron–thiolate complexes of the type [Fe2(μ‐bdt)(CO)6−xP(OMe3)x] (bdt=S2C6H4=benzenedithiolate,x≤2) are simplified models of iron–iron hydrogenase enzymes. Recently, we have shown that these water‐insoluble organometallic complexes, when included into micelles formed by sodium dodecyl sulfate (SDS), are good catalysts for the electrochemical production of hydrogen in aqueous solutions at pH<6. We herein report that the all‐CO derivative [Fe2(μ‐bdt)(CO)6] (1), owing to its comparatively low reduction potential, is also a robust molecular catalyst for visible‐light‐driven production of H2in aqueous SDS solutions at pH 10.5. Irradiation atλ=455 nm of a system consisting of complex1, Eosin Y as a sensitizer, and triethylamine as an electron donor produced up to 0.86 mL of H2in 4.5 h, corresponding to a turnover number of 117 mol of H2per mol of catalyst. In the presence of a large excess of sensitizer, the production of H2lasted for more than 30 h, stressing the relative stability of complex1under the photocatalytic conditions used herein. Thermodynamic considerations and UV/Vis spectroscopy experiments suggest that the catalytic cycle begins with the photo‐driven reduction of complex1. The reduced intermediate reacts with a proton source to yield iron hydride. Subsequent reduction and protonation steps produce H2, regenerating the starting complex. As a result, the iron–thiolate complex1is a versatile proton reduction catalyst that can utilize either solar or electrical energy inputs, providing a starting point for the construction of noble metal‐free molecular systems for renewable H2production.
Reduced Graphene Oxide/InGaZn Mixed Oxide Nanocomposite Photocatalysts for Hydrogen Production
Authors: Martha Satyabadi , Padhi Deepak Ku. , Parida Kulamani 
Published: October 2013

AbstractA series of reduced graphene oxide and indium–gallium–zinc mixed oxide (RGO/IGZ) nanocomposites were successfully synthesised by a simple one‐step hydrothermal method. The as‐synthesised nanocomposites were characterised by crystallographic, microscopic, and spectroscopic methods to explore the robust photocatalytic activity of the prepared materials. XRD patterns confirmed the formation of highly pure, single‐phase, hexagonal In2Ga2ZnO7 with no impurity‐related peaks. All the photocatalysts absorbed visible light as observed from the diffuse reflectance UV/Vis spectra. The electron–hole recombination is effectively minimised by the formation of an RGO/metal oxide nanocomposite, which was successfully derived from a photoluminescence (PL) study and photoelectrochemical measurements. The decoration of IGZ nanocrystals onto reduced graphene sheets leads to significant quenching of its luminescent intensity, dramatically improved photocurrent generation (33 times more than neat IGZ) and significantly enhanced photostability. The high photocatalytic activity for H2 production is explained by the strong interaction between the IGZ nanocrystals with RGO sheets, low PL intensity, high photocurrent and large surface area.
Subcellular transcriptomics—Dissection of the mRNA composition in the axonal compartment of sensory neurons
Authors: Minis Adi , Dahary Dvir , Manor Ohad , Leshkowitz Dena , Pilpel Yitzhak , Yaron Avraham 
Published: October 2013

ABSTRACTRNA localization is a regulatory mechanism that is conserved from bacteria to mammals. Yet, little is known about the mechanism and the logic that govern the distribution of RNA transcripts within the cell. Here, we present a novel organ culture system, which enables the isolation of RNA specifically from NGF dependent re‐growing peripheral axons of mouse embryo, sensory neurons. In combination with massive parallel sequencing technology, we determine the subcellular localization of most transcripts in the transcriptome. We found that the axon is enriched in mRNAs that encode secreted proteins, transcription factors, and the translation machinery. In contrast, the axon was largely depleted from mRNAs encoding transmembrane proteins, a particularly interesting finding, since many of these gene products are specifically expressed in the tip of the axon at the protein level. Comparison of the mitochondrial mRNAs encoded in the nucleus with those encoded in the mitochondria, uncovered completely different localization pattern, with the latter much enriched in the axon fraction. This discovery is intriguing since the protein products encoded by the nuclear and mitochondrial genome form large co‐complexes. Finally, focusing on alternative splice variants that are specific to axonal fractions, we find short sequence motifs that are enriched in the axonal transcriptome. Together our findings shed light on the extensive role of RNA localization and its characteristics. © 2013 Wiley Periodicals, Inc. Develop Neurobiol 74: 365–381, 2014
Multilocus analyses indicate a mosaic distribution of hybrid populations in ground squirrels (genusIctidomys)
Authors: Thompson Cody W. , Anwarali Khan Faisal Ali , Stangl Frederick B. , Baker Robert J. , Bradley Robert D. 
Published: October 2013

AbstractDNAsequence data from mitochondrial cytochrome‐b(Cytb) and Y‐linked structural maintenance of chromosomes (SmcY) genes were combined with 478 nuclear loci obtained from amplified fragment length polymorphisms (AFLP) to assess the extent of hybridization and genetic spatial structure of populations in two hybridizing species of ground squirrel (Ictidomys parvidensandIctidomys tridecemlineatus). Based onAFLPanalyses of 134 individuals from 28 populations, 10 populations were identified that possessed hybrid individuals. Overall estimates ofFSTvalues revealed strong support for population structure in theCytb data set; however, analyses of theSmcYgene and theAFLPdata indicated ongoing gene flow between species. PairwiseFSTcomparisons of populations were not significant for theSmcYgene; although they were significant for theCytb gene, indicating that these populations were structured and that gene flow was minimal. Therefore, gene flow betweenI. parvidensandI. tridecemlineatusappeared to be restricted to populations that exhibited hybridization. In addition, the fragmented nature of the geographic landscape suggested limited gene flow between populations. As a result, the distributional pattern of interspersed parental and hybrid populations were compatible with a mosaic hybrid zone model. Because ground squirrels display female philopatry and male‐biased dispersal, the ecology of these species is compatible with this hypothesis.
Metacommunity structuring in stream networks: roles of dispersal mode, distance type, and regional environmental context
Authors: Grönroos Mira , Heino Jani , Siqueira Tadeu , Landeiro Victor L. , Kotanen Juho , Bini Luis M. 
Published: October 2013

AbstractWithin a metacommunity, both environmental and spatial processes regulate variation in local community structure. The strength of these processes may vary depending on species traits (e.g., dispersal mode) or the characteristics of the regions studied (e.g., spatial extent, environmental heterogeneity). We studied the metacommunity structuring of three groups of stream macroinvertebrates differing in their overland dispersal mode (passive dispersers with aquatic adults; passive dispersers with terrestrial adults; active dispersers with terrestrial adults). We predicted that environmental structuring should be more important for active dispersers, because of their better ability to track environmental variability, and that spatial structuring should be more important for species with aquatic adults, because of stronger dispersal limitation. We sampled a total of 70 stream riffle sites in three drainage basins. Environmental heterogeneity was unrelated to spatial extent among our study regions, allowing us to examine the effects of these two factors on metacommunity structuring. We used partial redundancy analysis and Moran's eigenvector maps based on overland and watercourse distances to study the relative importance of environmental control and spatial structuring. We found that, compared with environmental control, spatial structuring was generally negligible, and it did not vary according to our predictions. In general, active dispersers with terrestrial adults showed stronger environmental control than the two passively dispersing groups, suggesting that the species dispersing actively are better able to track environmental variability. There were no clear differences in the results based on watercourse and overland distances. The variability in metacommunity structuring among basins was not related to the differences in the environmental heterogeneity and spatial extent. Our study emphasized that (1) environmental control is prevailing in stream metacommunities, (2) dispersal mode may have an important effect on metacommunity structuring, and (3) some factors other than spatial extent or environmental heterogeneity contributed to the differences among the basins.