bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterogeneity of Radial Glia-Like Cells in the Adult Hippocampus
Authors: Gebara Elias , Bonaguidi Michael Anthony , Beckervordersandforth Ruth , Sultan Sébastien , Udry Florian , Gijs Pieter-Jan , Lie Dieter Chichung , Ming Guo-Li , Song Hongjun , Toni Nicolas 
Published: January 2016

Abstract
Adult neurogenesis is tightly regulated by the neurogenic niche. Cellular contacts between niche cells and neural stem cells are hypothesized to regulate stem cell proliferation or lineage choice. However, the structure of adult neural stem cells and the contact they form with niche cells are poorly described. Here, we characterized the morphology of radial glia-like (RGL) cells, their molecular identity, proliferative activity, and fate determination in the adult mouse hippocampus. We found the coexistence of two morphotypes of cells with prototypical morphological characteristics of RGL stem cells: Type α cells, which represented 76% of all RGL cells, displayed a long primary process modestly branching into the molecular layer and type β cells, which represented 24% of all RGL cells, with a shorter radial process highly branching into the outer granule cell layer-inner molecular layer border. Stem cell markers were expressed in type α cells and coexpressed with astrocytic markers in type β cells. Consistently, in vivo lineage tracing indicated that type α cells can give rise to neurons, astrocytes, and type β cells, whereas type β cells do not proliferate. Our results reveal that the adult subgranular zone of the dentate gyrus harbors two functionally different RGL cells, which can be distinguished by simple morphological criteria, supporting a morphofunctional role of their thin cellular processes. Type β cells may represent an intermediate state in the transformation of type α, RGL stem cells, into astrocytes.
DNA-damage response gene GADD45A induces differentiation in hematopoietic stem cells without inhibiting cell cycle or survival
Authors: Wingert Susanne , Thalheimer Frederic B. , Haetscher Nadine , Rehage Maike , Schroeder Timm , Rieger Michael A. 
Published: January 2016

Abstract
Hematopoietic stem cells (HSCs) maintain blood cell production life-long by their unique abilities of self-renewal and differentiation into all blood cell lineages. Growth arrest and DNA-damage-inducible 45 alpha (GADD45A) is induced by genotoxic stress in HSCs. GADD45A has been implicated in cell cycle control, cell death and senescence, as well as in DNA-damage repair. In general, GADD45A provides cellular stability by either arresting the cell cycle progression until DNA damage is repaired or, in cases of fatal damage, by inducing apoptosis. However, the function of GADD45A in hematopoiesis remains controversial. We revealed the changes in murine HSC fate control orchestrated by the expression of GADD45A at single cell resolution. In contrast to other cellular systems, GADD45A expression did not cause a cell cycle arrest or an alteration in the decision between cell survival and apoptosis in HSCs. Strikingly, GADD45A strongly induced and accelerated the differentiation program in HSCs. Continuous tracking of individual HSCs and their progeny via time-lapse microscopy elucidated that once GADD45A was expressed, HSCs differentiate into committed progenitors within 29 hours. GADD45A-expressing HSCs failed to long-term reconstitute the blood of recipients by inducing multilineage differentiation in vivo. Importantly, γ-irradiation of HSCs induced their differentiation by upregulating endogenous GADD45A. The differentiation induction by GADD45A was transmitted by activating p38 Mitogen-activated protein kinase (MAPK) signaling and allowed the generation of megakaryocytic-erythroid, myeloid, and lymphoid lineages. These data indicate that genotoxic stress-induced GADD45A expression in HSCs prevents their fatal transformation by directing them into differentiation and thereby clearing them from the system.
Coalitional game‐based behavior analysis for spectrum access in cognitive radios
Authors: Belghiti Imane Daha , Elmachkour Mouna , Berrada Ismail , Kobbane Abdellatif , Ben‐Othman Jalel 
Published: January 2016

AbstractThe core of cognitive radio paradigm is to introduce cognitive devices able to opportunistically access the licensed radio bands. The coexistence of licensed and unlicensed users prescribes an effective spectrum hole‐detection and a non‐interfering sharing of those frequencies. Collaborative resource allocation and spectrum information exchange are required but often costly in terms of energy and delay. In this paper, each secondary user (SU) can achieve spectrum sensing and data transmission through a coalitional game‐based mechanism. SUs are called upon to report their sensing results to the elected coalition head, which properly decides on the channel state and the transmitter in each time slot according to a proposed algorithm. The goal of this paper is to provide a more holistic view on the spectrum and enhance the cognitive system performance through SUs behavior analysis. We formulate the problem as a coalitional game in partition form with non‐transferable utility, and we investigate on the impact of both coalition formation and the combining reports costs. We discuss the Nash Equilibrium solution for our coalitional game and propose a distributed strategic learning algorithm to illustrate a concrete case of coalition formation and the SUs competitive and cooperative behaviors inter‐coalitions and intra‐coalitions. We show through simulations that cognitive network performances, the energy consumption and transmission delay, improve evidently with the proposed scheme. Copyright © 2016 John Wiley & Sons, Ltd.
Hydrodynamics of swimming in stingrays: numerical simulations and the role of the leading-edge vortex
Authors: Bottom II R. G. , Borazjani I. , Blevins E. L. , Lauder G. V. 
Published: January 2016

Stingrays, in contrast with many other aquatic animals, have flattened disk-shaped bodies with expanded pectoral ‘wings’, which are used for locomotion in water. To discover the key features of stingray locomotion, large-eddy simulations of a self-propelled stingray, modelled closely after the freshwater stingray,Potamotrygon orbignyi, are performed. The stingray’s body motion was prescribed based on three-dimensional experimental measurement of wing and body kinematics in live stingrays at two different swimming speeds of 1.5 and$2.5L~\text{s}^{-1}$($L$is the disk length of the stingray). The swimming speeds predicted by the self-propelled simulations were within 12 % of the nominal swimming speeds in the experiments. It was found that the fast-swimming stingray (Reynolds number$Re=23\,000$and Strouhal number$St=0.27$) is approximately 12 % more efficient than the slow-swimming one ($Re=13\,500$,$St=0.34$). This is related to the wake of the fast- and slow-swimming stingrays, which was visualized along with the pressure on the stingray’s body. A horseshoe vortex was discovered to be present at the anterior margin of the stingray, creating a low-pressure region that enhances thrust for both fast and slow swimming speeds. Furthermore, it was found that a leading-edge vortex (LEV) on the pectoral disk of swimming stingrays generates a low-pressure region in the fast-swimming stingray, whereas the low- and high-pressure regions in the slow-swimming one are in the back half of the wing and not close to any vortical structures. The undulatory motion creates thrust by accelerating the adjacent fluid (the added-mass mechanism), which is maximized in the back of the wing because of higher undulations and velocities in the back. However, the thrust enhancement by the LEV occurs in the front portion of the wing. By computing the forces on the front half and the back half of the wing, it was found that the contribution of the back half of the wing to thrust in a slow-swimming stingray is several-fold higher than in the fast-swimming one. This indicates that the LEV enhances thrust in fast-swimming stingrays and improves the efficiency of swimming.
“If a Muslim says ‘homo’, nothing gets done”: Racist discourse and in-group identity construction in an LGBT youth group
Authors: Jones Lucy 
Published: January 2016

ABSTRACTThis article presents ethnographic data emerging from research with a group of LGBT young people, detailing the construction of a shared identity. Using discourse analysis, it shows how the group members position people of South Asian descent as a homogenous out-group, one framed as ‘other’ to their own in-group identity of ‘non-Asian’ due to the assumption that Asian people are homophobic. It is argued that this very local form of identity construction is facilitated by broader discourses of Islamophobia, as well as homonormative ideologies positioning gay people as white. The article therefore provides evidence to support Bucholtz & Hall's (2005) claim that identity positioning relates not only to the interactional moment and the norms of a given ethnographic context, but that it also encompasses macro-level discourses and ideologies. It also, however, reveals the pervasiveness of Islamophobic discourses in Britain today, and the marginalisation of LGBT people of colour. (LGBT identity, racist discourse, homonormativity, Islamophobia)*
S4AC Case Study: Enhancing Underserved Seniors’ Access to Health Promotion Programs
Authors: Koehn Sharon , Habib Sanzida , Bukhari Syeda 
Published: January 2016

RÉSUMÉLes Services de soutien pour les aînés projet communautaire sud-asiatique (SSAPCSA) ont été développé en réponse à la sous-utilisation des loisirs disponibles et des installations pour les aînés par des aînés sud-asiatiques qui étaient particulièrement nombreux dans une banlieue en Colombie-Britannique. Abordant ce problème a nécessité la collaboration de la municipalité et un organisme enregistré à but non-lucratif offrant un large éventail de services et de programmes aux communautés immigrantes et réfugiées. Grâce à la sensibilisation créative et l’hébergement, le projet a engagé plus de 100 personnes âgées qui parlent panjabi chaque année à diverses activités impliquant l’exercice. Les méthodes de recherche ont porté sur l’étude de cas avec le personnel et les participants actuels et anciens cadres de SSAPCSA comprennent l’observation participante, entretiens individuels, et des groupes de discussion. Les conclusions, vues à travers le prisme d'interprétation critique de la “cadre de la candidature,” révèlent les multiples façons dans lesquelles l’accès à la promotion de la santé et l’activité physique pour les immigrants plus âgés est un processus complexe et itératif de négociation à plusieurs niveaux.
A novel role for the tumour suppressor Nitrilase1 modulating the Wnt/β-catenin signalling pathway
Authors: Mittag Sonnhild , Valenta Tomas , Weiske Jörg , Bloch Laura , Klingel Susanne , Gradl Dietmar , Wetzel Franziska , Chen Yuan , Petersen Iver , Basler Konrad , Huber Otmar 
Published: January 2016

AbstractNitrilase1 was classified as a tumour suppressor in association with the fragile histidine-triad protein Fhit. However, knowledge about nitrilase1 and its tumour suppressor function is still limited. Whereas nitrilase1 and Fhit are discrete proteins in mammals, they are merged in Drosophila melanogaster and Caenorhabditis elegans. According to the Rosetta-Stone hypothesis, proteins encoded as fusion proteins in one organism and as separate proteins in another organism may act in the same signalling pathway. Although a direct interaction of human nitrilase1 and Fhit has not been shown, our previous finding that Fhit interacts with β-catenin and represses its transcriptional activity in the canonical Wnt pathway suggested that human nitrilase1 also modulates Wnt signalling. In fact, human nitrilase1 forms a complex with β-catenin and LEF-1/TCF-4, represses β-catenin-mediated transcription and shows an additive effect together with Fhit. Knockdown of human nitrilase1 enhances Wnt target gene expression. Moreover, our experiments show that β-catenin competes away human nitrilase1 from LEF-1/TCF and thereby contributes to the activation of Wnt-target gene transcription. Inhibitory activity of human nitrilase1 on vertebrate Wnt signalling was confirmed by repression of Wnt-induced double axis formation in Xenopus embryogenesis. In line with this finding, the Drosophila fusion protein Drosophila NitFhit directly binds to Armadillo and represses the Wingless pathway in reporter gene assays. Genetic experiments confirmed the repressive activity of Drosophila NitFhit on Wingless signalling in the Drosophila wing imaginal disc. In addition, colorectal tumour microarray analysis revealed a significantly reduced expression of human nitrilase1 in poorly differentiated tumours. Taken together, repression of the canonical Wnt pathway represents a new mechanism for the human nitrilase1 tumour suppressor function.
Local viscoelasticity of living cells measured by rotational magnetic spectroscopy
Authors: Berret J.-F. 
Published: January 2016

AbstractWhen submitted to a magnetic field, micron-size wires with superparamagnetic properties behave as embedded rheometers and represent interesting sensors for microrheology. Here we use rotational magnetic spectroscopy to measure the shear viscosity of the cytoplasm of living cells. We address the question of whether the cytoplasm is a viscoelastic liquid or an elastic gel. The main result of the study is the observation of a rotational instability between a synchronous and an asynchronous regime of rotation, found for murine fibroblasts and human cancer cells. For wires of susceptibility 3.6, the transition occurs in the range 0.01–1 rad s−1. The determination of the shear viscosity (10–100 Pa s) and elastic modulus (5–20 Pa) confirms the viscoelastic character of the cytoplasm. In contrast to earlier studies, it is concluded that the interior of living cells can be described as a viscoelastic liquid, and not as an elastic gel.
Structure of the polyisoprenyl-phosphate glycosyltransferase GtrB and insights into the mechanism of catalysis
Authors: Ardiccioni Chiara , Clarke Oliver B. , Tomasek David , Issa Habon A. , von Alpen Desiree C. , Pond Heather L. , Banerjee Surajit , Rajashankar Kanagalaghatta R. , Liu Qun , Guan Ziqiang , Li Chijun , Kloss Brian , Bruni Renato , Kloppmann Edda , Rost Burkhard , Manzini M. Chiara , Shapiro Lawrence , Mancia Filippo 
Published: January 2016

AbstractThe attachment of a sugar to a hydrophobic polyisoprenyl carrier is the first step for all extracellular glycosylation processes. The enzymes that perform these reactions, polyisoprenyl-glycosyltransferases (PI-GTs) include dolichol phosphate mannose synthase (DPMS), which generates the mannose donor for glycosylation in the endoplasmic reticulum. Here we report the 3.0Å resolution crystal structure of GtrB, a glucose-specific PI-GT from Synechocystis, showing a tetramer in which each protomer contributes two helices to a membrane-spanning bundle. The active site is 15 Å from the membrane, raising the question of how water-soluble and membrane-embedded substrates are brought into apposition for catalysis. A conserved juxtamembrane domain harbours disease mutations, which compromised activity in GtrB in vitro and in human DPM1 tested in zebrafish. We hypothesize a role of this domain in shielding the polyisoprenyl-phosphate for transport to the active site. Our results reveal the basis of PI-GT function, and provide a potential molecular explanation for DPM1-related disease.
HSP90 regulates temperature-dependent seedling growth in Arabidopsis by stabilizing the auxin co-receptor F-box protein TIR1
Authors: Wang Renhou , Zhang Yi , Kieffer Martin , Yu Hong , Kepinski Stefan , Estelle Mark 
Published: January 2016

AbstractRecent studies have revealed that a mild increase in environmental temperature stimulates the growth of Arabidopsis seedlings by promoting biosynthesis of the plant hormone auxin. However, little is known about the role of other factors in this process. In this report, we show that increased temperature promotes rapid accumulation of the TIR1 auxin co-receptor, an effect that is dependent on the molecular chaperone HSP90. In addition, we show that HSP90 and the co-chaperone SGT1 each interact with TIR1, confirming that TIR1 is an HSP90 client. Inhibition of HSP90 activity results in degradation of TIR1 and interestingly, defects in a range of auxin-mediated growth processes at lower as well as higher temperatures. Our results indicate that HSP90 and SGT1 integrate temperature and auxin signalling in order to regulate plant growth in a changing environment.
A series connection architecture for large-area organic photovoltaic modules with a 7.5% module efficiency
Authors: Hong Soonil , Kang Hongkyu , Kim Geunjin , Lee Seongyu , Kim Seok , Lee Jong-Hoon , Lee Jinho , Yi Minjin , Kim Junghwan , Back Hyungcheol , Kim Jae-Ryoung , Lee Kwanghee 
Published: January 2016

AbstractThe fabrication of organic photovoltaic modules via printing techniques has been the greatest challenge for their commercial manufacture. Current module architecture, which is based on a monolithic geometry consisting of serially interconnecting stripe-patterned subcells with finite widths, requires highly sophisticated patterning processes that significantly increase the complexity of printing production lines and cause serious reductions in module efficiency due to so-called aperture loss in series connection regions. Herein we demonstrate an innovative module structure that can simultaneously reduce both patterning processes and aperture loss. By using a charge recombination feature that occurs at contacts between electron- and hole-transport layers, we devise a series connection method that facilitates module fabrication without patterning the charge transport layers. With the successive deposition of component layers using slot-die and doctor-blade printing techniques, we achieve a high module efficiency reaching 7.5% with area of 4.15 cm2.
Overlap microtubules link sister k-fibres and balance the forces on bi-oriented kinetochores
Authors: Kajtez Janko , Solomatina Anastasia , Novak Maja , Polak Bruno , Vukušić Kruno , Rüdiger Jonas , Cojoc Gheorghe , Milas Ana , Šumanovac Šestak Ivana , Risteski Patrik , Tavano Federica , Klemm Anna H. , Roscioli Emanuele , Welburn Julie , Cimini Daniela , Glunčić Matko , Pavin Nenad , Tolić Iva M. 
Published: January 2016

AbstractDuring metaphase, forces on kinetochores are exerted by k-fibres, bundles of microtubules that end at the kinetochore. Interestingly, non-kinetochore microtubules have been observed between sister kinetochores, but their function is unknown. Here we show by laser-cutting of a k-fibre in HeLa and PtK1 cells that a bundle of non-kinetochore microtubules, which we term ‘bridging fibre’, bridges sister k-fibres and balances the interkinetochore tension. We found PRC1 and EB3 in the bridging fibre, suggesting that it consists of antiparallel dynamic microtubules. By using a theoretical model that includes a bridging fibre, we show that the forces at the pole and at the kinetochore depend on the bridging fibre thickness. Moreover, our theory and experiments show larger relaxation of the interkinetochore distance for cuts closer to kinetochores. We conclude that the bridging fibre, by linking sister k-fibres, withstands the tension between sister kinetochores and enables the spindle to obtain a curved shape.
Pantheon 1.0, a manually verified dataset of globally famous biographies
Authors: Yu Amy Zhao , Ronen Shahar , Hu Kevin , Lu Tiffany , Hidalgo César A. 
Published: January 2016

AbstractWe present the Pantheon 1.0 dataset: a manually verified dataset of individuals that have transcended linguistic, temporal, and geographic boundaries. The Pantheon 1.0 dataset includes the 11,341 biographies present in more than 25 languages in Wikipedia and is enriched with: (i) manually verified demographic information (place and date of birth, gender) (ii) a taxonomy of occupations classifying each biography at three levels of aggregation and (iii) two measures of global popularity including the number of languages in which a biography is present in Wikipedia (L), and the Historical Popularity Index (HPI) a metric that combines information on L, time since birth, and page-views (2008–2013). We compare the Pantheon 1.0 dataset to data from the 2003 book, Human Accomplishments, and also to external measures of accomplishment in individual games and sports: Tennis, Swimming, Car Racing, and Chess. In all of these cases we find that measures of popularity (L and HPI) correlate highly with individual accomplishment, suggesting that measures of global popularity proxy the historical impact of individuals.
Probiotic treatment reduces appetite and glucose level in the zebrafish model
Authors: Falcinelli Silvia , Rodiles Ana , Unniappan Suraj , Picchietti Simona , Gioacchini Giorgia , Merrifield Daniel Lee , Carnevali Oliana 
Published: January 2016

AbstractThe gut microbiota regulates metabolic pathways that modulate the physiological state of hunger or satiety. Nutrients in the gut stimulate the release of several appetite modulators acting at central and peripheral levels to mediate appetite and glucose metabolism. After an eight-day exposure of zebrafish larvae to probiotic Lactobacillus rhamnosus, high-throughput sequence analysis evidenced the ability of the probiotic to modulate the microbial composition of the gastrointestinal tract. These changes were associated with a down-regulation and up-regulation of larval orexigenic and anorexigenic genes, respectively, an up-regulation of genes related to glucose level reduction and concomitantly reduced appetite and body glucose level. BODIPY-FL-pentanoic-acid staining revealed higher short chain fatty acids levels in the intestine of treated larvae. These results underline the capability of the probiotic to modulate the gut microbiota community and provides insight into how the probiotic interacts to regulate a novel gene network involved in glucose metabolism and appetite control, suggesting a possible role for L. rhamnosus in the treatment of impaired glucose tolerance and food intake disorders by gut microbiota manipulation.
The role of dung beetles in reducing greenhouse gas emissions from cattle farming
Authors: Slade Eleanor M. , Riutta Terhi , Roslin Tomas , Tuomisto Hanna L. 
Published: January 2016

AbstractAgriculture is one of the largest anthropogenic sources of greenhouse gases (GHGs), with dairy and beef production accounting for nearly two-thirds of emissions. Several recent papers suggest that dung beetles may affect fluxes of GHGs from cattle farming. Here, we put these previous findings into context. Using Finland as an example, we assessed GHG emissions at three scales: the dung pat, pasture ecosystem and whole lifecycle of milk or beef production. At the first two levels, dung beetles reduced GHG emissions by up to 7% and 12% respectively, mainly through large reductions in methane (CH4) emissions. However, at the lifecycle level, dung beetles accounted for only a 0.05–0.13% reduction of overall GHG emissions. This mismatch derives from the fact that in intensive production systems, only a limited fraction of all cow pats end up on pastures, offering limited scope for dung beetle mitigation of GHG fluxes. In contrast, we suggest that the effects of dung beetles may be accentuated in tropical countries, where more manure is left on pastures and dung beetles remove and aerate dung faster and that this is thus a key area for future research. These considerations give a new perspective on previous results and suggest that studies of biotic effects on GHG emissions from dung pats on a global scale are a priority for current research.