bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased depth to the water table during river drying decreases the resilience of Gammarus pulex and alters ecosystem function
Authors: Vander Vorste Ross , Mermillod‐Blondin F. , Hervant F. , Mons R. , Forcellini M. , Datry T. 
Published: December 2015

AbstractRiver drying has drastic immediate effects on benthic invertebrates, but their high resilience reduces long‐term effects on biodiversity and ecosystem functions (e.g. leaf litter decomposition). The hyporheic zone (saturated sediments below the riverbed) can be a refuge for invertebrates in dry rivers and a primary source of colonists supporting population resilience following flow resumption. However, factors such as the depth to the water table below the riverbed, which could determine the quality of the hyporheic refuge, are not well understood. We explored how depth to the water table (control, −5 cm, −30 cm and completely dry) during a 1‐week drying event affected the survival and return to the substrate surface (%RTS) of Gammarus pulex (Crustacea : Amphipoda) using laboratory mesocosms. We measured litter decomposition and Gammarus energy stores to examine effects on ecosystem function and energetic costs for organisms crawling deeper into the hyporheic zone. Two populations, collected from intermittent and perennial rivers, were used to evaluate inter‐population variability in response to drying. Survival and %RTS were reduced by ≤39% and 52%, respectively, in the −30 cm and dry treatments, and this had consequences for decomposition (≤46% reduction). Differences between populations in %RTS were high across treatments but did not generally affect survival and decomposition. Our results suggest that increases in depth to the water table during river drying, which often result from longer drying duration and water abstraction, could reduce invertebrate resilience and litter decomposition by diminishing the role of the hyporheic zone as a source of colonists. Copyright © 2015 John Wiley & Sons, Ltd.
Nonenzymatic Electrochemical Biosensor Based on Novel Hydrophilic Ferrocene‐terminated Hyperbranched Polymer and its Application in Glucose Detection
Authors: Li Hongling , Zhao Fengmei , Yue Lin , Li Song , Xiao Fengjuan 
Published: December 2015

AbstractWe designed a novel water soluble topological structure polymer‐ferrocene‐ terminated hyperbranched polyurethane (HPU‐Fc) with good water solubility. The redox behaviors and the electrochemical kinetics parameters of HPU‐Fcs were explored by cyclic voltammetry (CV) according to electrochemical principle. The topological structure polymer was applied for the design and engineering of non‐enzymatic glucose sensor. The designed sensor showed good response to glucose concentration with good stability, favorable accuracy and high selectivity. The electrode was also used to detect glucose in blood samples, and the glucose contents detected by the electrode were in good agreement with those from the hospital where a common automatic biochemical analyzer (HF240–300) was used. This finding makes HPU‐Fc a promising biosensor for directly sensing glucose.
Surface runoff and soil erosion under eucalyptus and oak canopy
Authors: Thompson Arnold , Davis Jerry D. , Oliphant Andrew J. 
Published: December 2015

AbstractTo assess potential differences in stormwater runoff and sediment yield between plots of blue gum eucalyptus (Eucalyptus globulus) and coast live oak (Quercus agrifolia), we measured runoff, sediment yield, water repellency and soil moisture at eight paired sites. Eucalyptus has been associated in many studies worldwide with elevated soil water repellency and increased runoff, a likely contributor to soil erosion. To better understand these connections and their relationship to land cover, there is a need for studies employing either rainfall simulators or natural rainfall. Our research employs the latter, and was subject to contrasting hydrologic conditions in the two years of the study. Fieldwork was conducted from October 2006 to February 2008 in the San Francisco Bay Area of central California. During the 2006–2007 winter wet season, runoff was significantly higher under eucalypts than at paired oak sites, and in the early phases of the season was connected with elevated water repellency. However, sediment yield at all sites during the 2006–2007 hydrologic year was below the detection limit of the Gerlach sediment collection traps, possibly due to a limited wet season, and only appeared as suspended sediment captured in overflow buckets. Intensive rainfall events in January 2008 however created substantial runoff of sediment and litter with significantly greater yield at oak sites compared to paired eucalyptus sites. Water repellency likely had little effect on runoff during these events, and the primary cause of greater erosion under oaks is the thinner cover of leaf litter in comparison to eucalyptus. Our study is limited to undisturbed sites with intact litter cover that have not experienced recent wildfires; if disturbed, we would expect a different picture given the propensity for crown fires of eucalypts, enhancement of rainsplash erosion, and the likely greater potential for stream‐connected sediment yield from post‐disturbance soil erosion events.
Paleotopographic controls on loess deposition in the Loess Plateau of China
Authors: Xiong Li‐Yang , Tang Guo‐An , Strobl Josef , Zhu A‐Xing 
Published: December 2015

AbstractThe underlying pre‐existing paleotopography directly influences the loess deposition process and shapes the morphology of current loess landforms. An understanding of the controlling effects of the underlying paleotopography on loess deposition is critical to revealing the mechanism of loess‐landform formation. However, these controlling effects exhibit spatial variation as well as uncertainty, depending on a study's data sources, methodologies and particular research scope. In this study, the geological history of a study area in the Loess Plateau of China that is subject to severe soil erosion is investigated using detailed geological information and digital elevation models (DEMs), and an underlying paleotopographic model of the area is constructed. Based on the models of modern terrain and paleotopography, we introduce a watershed hierarchy method to investigate the spatial variation of the loess‐landform inheritance relationship and reveal the loess deposition process over different scales of drainage. The landform inheritance relationships were characterized using a terrain‐relief change index (TRCI) and a bedrock terrain controllability index (BTCI). The results show that the TRCI appears to have an inverse relationship with increasing research scope, indicating that, compared with the paleotopography of the region, modern terrain has lower topographic relief over the entire area, while it has higher topographic relief in the smaller, local areas. The BTCI strengthens with increasing drainage area, which demonstrates a strong controlling effect over the entire study area, but a weak effect in the smaller, local areas because of the effect of paleotopography on modern terrain. The results provide for an understanding of the spatial variation of loess deposition in relation to paleotopography and contribute to the development of a process‐based loess‐landform evolution model. Copyright © 2015 John Wiley & Sons, Ltd.
Differences in structural covariance brain networks between behavioral variant frontotemporal dementia and Alzheimer's disease
Authors: Hafkemeijer Anne , Möller Christiane , Dopper Elise G. P. , Jiskoot Lize C. , van den Berg‐Huysmans Annette A. , van Swieten John C. , van der Flier Wiesje M. , Vrenken Hugo , Pijnenburg Yolande A. L. , Barkhof Frederik , Scheltens Philip , van der Grond Jeroen , Rombouts Serge A. R. B. 
Published: December 2015

AbstractDisease‐specific patterns of gray matter atrophy in Alzheimer's disease (AD) and behavioral variant frontotemporal dementia (bvFTD) overlap with distinct structural covariance networks (SCNs) in cognitively healthy controls. This suggests that both types of dementia target specific structural networks. Here, we study SCNs in AD and bvFTD. We used structural magnetic resonance imaging data of 31 AD patients, 24 bvFTD patients, and 30 controls from two centers specialized in dementia. Ten SCNs were defined based on structural covariance of gray matter density using independent component analysis. We studied group differences in SCNs using F‐tests, with Bonferroni corrected t‐tests, adjusted for age, gender, and study center. Associations with cognitive performance were studied using linear regression analyses. Cross‐sectional group differences were found in three SCNs (all P < 0.0025). In bvFTD, we observed decreased anterior cingulate network integrity compared with AD and controls. Patients with AD showed decreased precuneal network integrity compared with bvFTD and controls, and decreased hippocampal network and anterior cingulate network integrity compared with controls. In AD, we found an association between precuneal network integrity and global cognitive performance (P = 0.0043). Our findings show that AD and bvFTD target different SCNs. The comparison of both types of dementia showed decreased precuneal (i.e., default mode) network integrity in AD and decreased anterior cingulate (i.e., salience) network integrity in bvFTD. This confirms the hypothesis that AD and bvFTD have distinct anatomical networks of degeneration and shows that structural covariance gives valuable insights in the understanding of network pathology in dementia. Hum Brain Mapp 37:978–988, 2016. © 2015 Wiley Periodicals, Inc.
High‐Performance Work Systems in Professional Service Firms: Examining the Practices‐Resources‐Uses‐Performance Linkage
Authors: Fu Na , Flood Patrick C. , Bosak Janine , Rousseau Denise M. , Morris Tim , O'Regan Philip 
Published: December 2015

AbstractProfessional service firms (PSFs) play an important role in the knowledge‐based economy. Their success is highly dependent on their people, the knowledge resources they possess, and how they use these resources. However, how to systematically manage human resources to attain high performance is not fully understood. This study addresses this issue by investigating the linkage mechanisms through which high‐performance work systems (HPWS) influence the performance of PSFs. We integrate resource‐based and dynamic capability theories in order to identify and investigate two intervening mechanisms that link HR practices to firm performance. The first mechanism is the intellectual capitalresourcescomprising the human, social, and organizational capital that HPWS create. The second mechanism is theusesto which both HPWS and resources can be applied, operationalized as organizational ambidexterity, the simultaneous exploitation of existing knowledge and exploration of new knowledge. These mechanisms are hypothesized to link HPWS to firm performance in the form of a practices‐resources‐uses‐performance linkage model. Results from a longitudinal study of 93 accounting firms support this linkage model. © 2015 Wiley Periodicals, Inc.
A simple method to establish calcite:aragonite ratios in archaeological mollusc shells
Authors: Loftus Emma , Rogers Keith , Lee‐Thorp Julia 
Published: December 2015

ABSTRACTOxygen isotope thermometry from archaeological mollusc shells relies on preservation of the original crystal structure; in particular that metastable aragonite has not undergone recrystallization to calcite. Conventional methods for detecting recrystallization, however, require large sample sizes and extensive calibration, so that they cannot address variable shifts across sampling surfaces and in practice are rarely fully applied. Here we show that attenuated total reflectance Fourier transform infrared spectroscopy (FTIR‐ATR) can be applied to rapidly quantify biogenic aragonite and recrystallized calcite contents in mollusc shells at a sufficient level of accuracy. We established a series of calibration curves based on artificial mixtures of calcite and aragonite for comparison with archaeological samples. This method offers an improvement over existing tools. Most importantly, spectra can be determined from small samples that can be recovered for subsequent isotope analysis, thus allowing assessments of crystal structure at high spatial resolution across the shell surface and within an entire assemblage.
An Emerging Unified View of Dynamic Interphases in Polymers
Authors: Simmons David S. 
Published: December 2015

The properties of nanostructured polymeric materials reflect the presence of a dynamic interphase in which polymer segmental dynamics, glass formation, mechanics, and transport properties are altered from their bulk states. Examples include nanoconfinement effects on polymer nanofilms, reinforcement effects in polymer nanocomposites and filled rubbers, formation of a rigid amorphous fraction in semicrystalline polymers, and observation of suppressed‐mobility domains around ionic aggregates in ionomers. Whereas many of these phenomena have been viewed as emerging from system‐specific mechanisms, here recent work is highlighted that contributes to an emerging unified understanding of the dynamic interphase in all of these systems. This view suggests that the size scales of dynamic interphases in polymers are generally determined by the scale of cooperative rearrangements intrinsic to relaxation dynamics in supercooled glass‐forming liquids. It also implicates alterations in local segmental rattling as playing a central role in the dynamic interphase, and it suggests that near‐interface modifications in dynamics exhibit a general dependence on the interfacial work of adhesion and the relative high‐frequency moduli of the interface‐adjacent domains.
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The proline‐rich region of glyceraldehyde‐3‐phosphate dehydrogenase from human sperm may bind SH3 domains, as revealed by a bioinformatic study of low‐complexity protein segments
Authors: Tatjewski Marcin , Gruca Aleksandra , Plewczynski Dariusz , Grynberg Marcin 
Published: December 2015

SUMMARYGlyceraldehyde‐3‐phosphate dehydrogenase from human sperm (GAPDHS) provides energy to the sperm flagellum, and is therefore essential for sperm motility and male fertility. This isoform is distinct from somatic GAPDH, not only in being specific for the testis but also because it contains an additional amino‐terminal region that encodes a proline‐rich motif that is known to bind to the fibrous sheath of the sperm tail. By conducting a large‐scale sequence comparison on low‐complexity sequences available in databases, we identified a strong similarity between the proline‐rich motif from GAPDHS and the proline‐rich sequence from Ena/vasodilator‐stimulated phosphoprotein‐like (EVL), which is known to bind an SH3 domain of dynamin‐binding protein (DNMBP). The putative binding partners of the proline‐rich GAPDHS motif include SH3 domain‐binding protein 4 (SH3BP4) and the IL2‐inducible T‐cell kinase/tyrosine‐protein kinase ITK/TSK (ITK). This result implies that GAPDHS participates in specific signal‐transduction pathways. Gene Ontology category‐enrichment analysis showed several functional classes shared by both proteins, of which the most interesting ones are related to signal transduction and regulation of hydrolysis. Furthermore, a mutation of one EVL proline to leucine is known to cause colorectal cancer, suggesting that mutation of homologous amino acid residue in the GAPDHS motif may be functionally deleterious. Mol. Reprod. Dev. 83: 144–148, 2016. © 2015 Wiley Periodicals, Inc.
Bone morphogenetic protein 4 and retinoic acid trigger bovine VASA homolog expression in differentiating bovine induced pluripotent stem cells
Authors: Malaver‐Ortega Luis F. , Sumer Huseyin , Jain Kanika , Verma Paul J. 
Published: December 2015

SUMMARYPrimordial germ cells (PGCs) are the earliest identifiable and completely committed progenitors of female and male gametes. They are obvious targets for genome editing because they assure the transmission of desirable or introduced traits to future generations. PGCs are established at the earliest stages of embryo development and are difficult to propagate in vitro—two characteristics that pose a problem for their practical application. One alternative method to enrich for PGCs in vitro is to differentiate them from pluripotent stem cells derived from adult tissues. Here, we establish a reporter system for germ cell identification in bovine pluripotent stem cells based on green fluorescent protein expression driven by the minimal essential promoter of the bovine Vasa homolog (BVH) gene, whose regulatory elements were identified by orthologous modelling of regulatory units. We then evaluated the potential of bovine induced pluripotent stem cell (biPSC) lines carrying the reporter construct to differentiate toward the germ cell lineage. Our results showed that biPSCs undergo differentiation as embryoid bodies, and a fraction of the differentiating cells expressed BVH. The rate of differentiation towards BVH‐positive cells increased up to tenfold in the presence of bone morphogenetic protein 4 or retinoic acid. Finally, we determined that the expression of key PGC genes, such as BVH or SOX2, can be modified by pre‐differentiation cell culture conditions, although this increase is not necessarily mirrored by an increase in the rate of differentiation. Mol. Reprod. Dev. 83: 149–161, 2016. © 2015 Wiley Periodicals, Inc.
Atomistic analysis of the electronic structure of m‐plane InGaN/GaN quantum wells: Carrier localization effects in ground and excited states due to random alloy fluctuations
Authors: Tanner Daniel P. , Caro Miguel A. , O'Reilly Eoin P. , Schulz Stefan 
Published: December 2015

AbstractWe present a detailed atomistic analysis of the electronic properties of m‐plane InGaN/GaN quantum wells. The tight‐binding model used treats realistically sized systems atomistically and accounts for compositional and structural inhomogeneities. Local variation in strain and built‐in potential arising from random alloy fluctuations are explicitly included in the model. Many energy states of the supercells considered are calculated in order to determine the impact of the alloy fluctuations on the electronic structure of the system under investigation. We find that while the electrons are relatively insensitive to the local indium environment, the hole states are highly sensitive to it and are subject to very strong localization effects. These effects persist several states into the valence band. This strong localization of the hole states leads to a very broad distribution of ground state energies in different random configurations. Furthermore, we see that the localization leads to poor overlap between different hole states resulting in a reduced probability of transfer of carriers between different states. This feature should play an important role for transport properties in m‐plane InGaN/GaN QWs.
An improved method of high‐precision determination of Δ17O of CO2 by catalyzed exchange with O2 using hot platinum
Authors: Mahata Sasadhar , Bhattacharya S. K. , Liang Mao‐Chang 
Published: December 2015

RationaleCO2 and O2 can exchange their oxygen isotopes rapidly in the presence of hot (~670 °C) platinum and this has led to a method for determining the δ17O value of a CO2 sample. We have improved the method to achieve a precision of 0.008 ‰ (1‐σ standard deviation) in the determination of δ17O values. Such high precision is essential to identify the stratospheric component in tropospheric CO2 and use it for global carbon flux studies. The crucial issue in the accurate determination of the δ17O value is estimation of a correction factor, which depends on the amount ratio CO2/O2. An attempt was also made to investigate the mechanism of exchange with their controlling parameters.MethodsThe oxygen isotopes of a CO2 sample gas are exchanged with those of an appropriate amount of tank O2 in the presence of hot platinum. The pre‐exchange CO2 and O2 gas samples as well as the post‐exchange O2 sample are analyzed by isotope ratio mass spectrometry. A mixing model was developed involving the δ18O value of the CO2 and δ17O and δ18O values of pre‐ and post‐exchange O2 to obtain the δ17O value of the CO2 sample. A correction to the measured value was determined to obtain the actual value with high accuracy and precision.ResultsTo obtain a precision better than 0.01 ‰ requires the amount ratio CO2/O2 to be controlled to better than ~15 %. We also find that the oxygen isotopes are nearly homogeneously distributed between the O2 and the CO2 molecules. In addition, determination of the 16O13C18O/16O12C16O isotopologue ratio in the CO2 shows that the abundance of 16O13C18O is close to that expected for random partitioning of the isotopes among the CO2 isotopologues.ConclusionsThe isotopic scrambling between O2 and CO2 that occurs on hot platinum allows one to accurately determine the δ17O values of CO2 through isotopic analysis of O2. Copyright © 2015 John Wiley & Sons, Ltd.
TGF-β1 and GDF5 Act Synergistically to Drive the Differentiation of Human Adipose Stromal Cells toward Nucleus Pulposus-like Cells
Authors: Colombier Pauline , Clouet Johann , Boyer Cécile , Ruel Maëva , Bonin Gaëlle , Lesoeur Julie , Moreau Anne , Fellah Borhane-Hakim , Weiss Pierre , Lescaudron Laurent , Camus Anne , Guicheux Jérôme 
Published: December 2015

Abstract
Degenerative disc disease (DDD) primarily affects the central part of the intervertebral disc namely the nucleus pulposus (NP). DDD explains about 40% of low back pain and is characterized by massive cellular alterations that ultimately result in the disappearance of resident NP cells. Thus, repopulating the NP with regenerative cells is a promising therapeutic approach and remains a great challenge. The objectives of this study were to evaluate the potential of growth factor-driven protocols to commit human adipose stromal cells (hASCs) toward NP-like cell phenotype and the involvement of Smad proteins in this differentiation process. Here, we demonstrate that the transforming growth factor-β1 and the growth differentiation factor 5 synergistically drive the nucleopulpogenic differentiation process. The commitment of the hASCs was robust and highly specific as attested by the expression of NP-related genes characteristic of young healthy human NP cells. In addition, the engineered NP-like cells secreted an abundant aggrecan and type II collagen rich extracellular matrix comparable with that of native NP. Furthermore, we demonstrate that these in vitro engineered cells survived, maintained their specialized phenotype and secretory activity after in vivo transplantation in nude mice subcutis. Finally, we provide evidence suggesting that the Smad 2/3 pathway mainly governed the acquisition of the NP cell molecular identity while the Smad1/5/8 pathway controlled the NP cell morphology. This study offers valuable insights for the development of biologically-inspired treatments for DDD by generating adapted and exhaustively characterized autologous regenerative cells.
Unified cyclic stress‐strain model for FRP‐confined concrete circular, square and rectangular prisms
Authors: Ziaadiny Hadi , Abbasnia Reza 
Published: December 2015

AbstractThe behaviour and modelling of concrete columns confined with FRP composites under monotonic compression has been extensively studied, but far fewer studies of the cyclic behaviour of FRP‐confined circular and rectangular columns have been carried out. A reliable model indicating the cyclic stress‐strain behaviour of FRP‐confined columns is of great importance, especially for seismic retrofits and the design of these columns. In this paper, based on the results from a series of cyclic compressive loading tests on FRP‐confined specimens, a unified cyclic stress‐strain model is proposed for circular, square and rectangular columns confined with FRP composites. The model contains different parts of the cyclic stress‐strain curve, including plastic strain, maximum strain in unloading path and corresponding stress, stress deterioration, effect of loading history, partial unloading and partial reloading. New expressions are also proposed for predicting unloading and reloading paths. The proposed model agrees well with the test results.