bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydrological gradients and functional diversity of plants drive ecosystem processes inPoyang Lakewetland
Authors: Fu Hui , Lou Qian , Dai Taotao , Yuan Guixiang , Huang Zhenrong , Ge Dabing , Zou Dongsheng , Li Wei , Liu Qiaolin , Wu Aiping , Guo Chunjing , Zhong Jiayou , Fang Shaowen , Hu Jianmin 
Published: February 2018

AbstractFunctional trait approaches have greatly improved the mechanistic understanding of the impacts of biodiversity in ecosystem. We evaluated how hydrological gradients (i.e., soil water content and elevation) affected the taxonomic diversity, functional identity, and functional diversity and assessed how changes in these measures of diversity ultimately drove variations in above‐ground biomass (AGB). Results showed that a combination of hydrological gradients and functional trait composition (i.e., the community weighted means, the single‐trait functional diversity and the multiple‐trait functional diversity) better explained variations (40.8%) of AGB. No significant relationships between taxonomic diversity and AGB were observed. The dominant species became taller with thicker stem, and co‐occurring species showed greater divergent distribution of stem diameter towards higher soil water content. As elevation increased, the dominant plant had thinner leaves with later onset of flowering and longer flowering duration, and co‐occurring species showed less divergent distribution of lamina thickness and leaf dry‐mass content. Our results highlighted that the positive biodiversity–ecosystem functioning relations were largely attributed to the co‐operations of selection and complementary effects, as evidences showed that the dominant trait values (i.e., community weighted mean of shoot height) and trait diversity (i.e., functional evenness) improved biomass production of wetland plants.
It takes a few to tango: changing climate and fire regimes can cause regeneration failure of two subalpine conifers
Authors: Hansen Winslow D. , Braziunas Kristin H. , Rammer Werner , Seidl Rupert , Turner Monica G. 
Published: February 2018

AbstractEnvironmental change is accelerating in the 21st century, but how multiple drivers may interact to alter forest resilience remains uncertain. In forests affected by large high‐severity disturbances, tree regeneration is a resilience linchpin that shapes successional trajectories for decades. We modeled stands of two widespread western U.S. conifers, Douglas‐fir (Pseudotsuga menziesii var. glauca), and lodgepole pine (Pinus contorta var. latifolia), in Yellowstone National Park (Wyoming, USA) to ask (1) What combinations of distance to seed source, fire return interval, and warming‐drying conditions cause postfire tree‐regeneration failure? (2) If postfire tree regeneration was successful, how does early tree density differ under future climate relative to historical climate? We conducted a stand‐level (1 ha) factorial simulation experiment using the individual‐based forest process model iLand to identify combinations of fire return interval (11–100 yr), distance to seed source (50–1,000 m), and climate (historical, mid‐21st century, late‐21st century) where trees failed to regenerate by 30‐yr postfire. If regeneration was successful, we compared stand densities between climate periods. Simulated postfire regeneration were surprisingly resilient to changing climate and fire drivers. Douglas‐fir regeneration failed more frequently (55%) than lodgepole pine (28% and 16% for non‐serotinous and serotinous stands, respectively). Distance to seed source was an important driver of regeneration failure for Douglas‐fir and non‐serotinous lodgepole pine; regeneration never failed when stands were 50 m from a seed source and nearly always failed when stands were 1 km away. Regeneration of serotinous lodgepole pine only failed when fire return intervals were ≤20 yr and stands were far (1 km) from a seed source. Warming climate increased regeneration success for Douglas‐fir but did not affect lodgepole pine. If regeneration was successful, postfire density varied with climate. Douglas‐fir and serotinous lodgepole pine regeneration density both increased under 21st‐century climate but in response to different climate variables (growing season length vs. cold limitation). Results suggest that, given a warmer future with larger and more frequent fires, a greater number of stands that fail to regenerate after fires combined with increasing density in stands where regeneration is successful could produce a more coarse‐grained forest landscape.
Establishing a sensitive capillary electrophoresis‐UV method for direct determination of amino acids to evaluate vinegar quality
Authors: Luo Tian , Dong Yue , He Shujuan , Yang Jing , Dong Yuming 
Published: February 2018

AbstractIn this study, the capillary electrophoresis method with ultraviolet detection was established to directly determine amino acids in vinegar, according to the coordination interaction between amino acids (AAs) and copper ions. The online sweeping technique was combined to improve the detection sensitivity. The quality of vinegar was evaluated with AAs as parameters by United Nations Food Agriculture Organization/Word Health Organization AAs model and principal component analysis. Optimum conditions were obtained under 50 mM CuSO4 and adjusted pH 4.40 with 8 mM acetate, 70 s injection time, 22.5 kV separation voltage, and 254 nm detected wavelength. Method validation, indicating good linearity (R2 > 0.9989), precision with an RSD less than 8.0% (n = 5), LOD (0.13–0.25 μg/mL), LOQ (0.43–0.83 μg/mL) and recovery (80.5–112.6%). Under the optimal conditions, AAs in vinegar can be directly separated which is propitious for the quality evaluation of vinegar.
Experimental Study of MgCl2 ⋅ 6 H2O as Thermochemical Energy Storage Material
Authors: Kohler Tobias , Biedermann Thomas , Müller Karsten 
Published: February 2018

AbstractHydrates of magnesium chloride are interesting as a thermochemical energy storage material. An open storage system was set‐up, which enables the reaction of water vapor with the salt hydrate at a given relative humidity. It is demonstrated that hydrates of magnesium chloride are only suited if the relative humidity is below 30 %. Otherwise the hygroscopic salt will cause the formation of an aqueous, liquid phase. This liquid inhibits mass transport and leads to the agglomeration of particles. As a consequence of the low partial pressure of the water, the reaction is very slow. Therefore, rather low effective energy densities of around 300 kJ kg−1 were measured. A way to enable higher humidities is to use a solid support like zeolite 13X. However, the adsorption of water vapor on the zeolite, without magnesium chloride, reached higher energy densities even at low relative humidity. Thus, it must be concluded that hydration of magnesium chloride for thermochemical energy storage cannot be recommended for most technical applications.
Seismic performance of buildings retrofitted with nonlinear viscous dampers and adjacent reaction towers
Authors: Impollonia Nicola , Palmeri Alessandro 
Published: February 2018

SummaryAn effective strategy of seismic retrofitting consists of installing nonlinear viscous dampers between the existing building, with insufficient lateral resistance, and some auxiliary towers, specially designed and erected as reaction structures. This allows improving the seismic performance of the existing building without any major alteration to its structural and nonstructural elements, which makes this approach particularly appealing for buildings with heritage value. In this paper, the nonlinear governing equations of the coupled lateral‐torsional seismic motion are derived from first principles for the general case of a multistory building connected at various locations in plan and in elevation to an arbitrary number of multistory towers. This formulation is then used to assess the performance of the proposed retrofitting strategy for a real case study, namely, a 5‐story student hall of residence in the city of Messina, Italy. The results of extensive time‐history analyses highlight the key design considerations associated with the stiffness of the reaction towers and the mechanical parameters of the nonlinear viscous dampers, confirming the validity of this approach.
A well‐preserved Eemian incised‐valley fill in the southern North Sea Basin, Belgian Continental Shelf ‐ Coastal Plain: Implications for northwest European landscape evolution
Authors: De Clercq M. , Missiaen T. , Wallinga J. , Zurita Hurtado O. , Versendaal A. , Mathys M. , De Batist M. 
Published: February 2018

AbstractThis paper demonstrates that the Belgian Continental Shelf and coastal plain occupy a key position between the depositional North Sea Basin and the erosional area of the Dover Strait as it is an area where erosional landforms and fragmented sedimentary sequences provide new evidence on northwest European landscape evolution. The study area hosts 20–30 m thick penultimate to last glacial sand‐dominated sequences that are preserved within the buried palaeo‐Scheldt Valley. Here, we build on the results of previous seismo‐ and lithostratigraphical studies, and present new evidence from biostratigraphical analysis, OSL dating and depth‐converted structure maps, together revealing a complex history of deposition and landscape evolution controlled by climate change, sea‐level fluctuations and glacio‐isostasy. This study presents strong new supportive evidence on the development of the incised palaeo‐Scheldt Valley landform that became established towards the end of the penultimate glacial period (MIS 6; Saalian) as a result of glacio‐isostatic forebulge updoming, proglacial lake drainage and subsequent collapse of a forebulge between East Anglia and Belgium following ice‐sheet growth, disintegration and retreat in areas to the north. The majority of the incised‐valley fill is of estuarine to shallow marine depositional context deposited during the transgression and high‐stand of the last interglacial (MIS 5e: Eemian). A thin upper part of the valley fill consists of last glacial (MIS 5d‐2: Weichselian) fluvial sediments that show a gradual decrease and retreat of fluvial activity to inland, upstream reaches of the valley system until finally the valley ceases to exist as the combined result of climate‐driven aeolian activity and possibly also glacio‐isostatic adjustment. Thus, strong contrasts exist between the palaeo‐Scheldt Valley and estuary systems of the penultimate glacial maximum to Last Interglacial (Saalian, Eemian), the beginning of the Last Glacial (Weichselian Early Glacial and Early‐Middle Pleniglacial), and the Last Glacial Maximum to Holocene. Copyright © 2018 John Wiley & Sons, Ltd.
Performance analysis of SFBC‐OFDM system with channel estimation error over generalized fading channels
Authors: Singh Daljeet , Joshi Hem Dutt 
Published: February 2018

AbstractIn this paper, the performance of space‐frequency block code orthogonal frequency‐division multiplexing (SFBC‐OFDM) system is analyzed over different fading channels using a generalized approach. General closed‐form expressions of average bit error rate (ABER) are derived for SFBC‐OFDM system. Both M‐ary phase‐shift keying and M‐ary quadrature amplitude modulation techniques have been considered in this analysis. The effect of imperfect channel estimation on ABER is included while deriving the ABER expression. The derived expressions are applicable under any given fading conditions provided that the moment‐generating function of fading channel is known. Simulation results are provided to verify the numerical results obtained from the derived expressions.
An SPH multi‐fluid model based on quasi buoyancy for interface stabilization up to high density ratios and realistic wave speed ratios
Authors: Kruisbrink A.C.H. , Pearce F.R. , Yue T. , Morvan H.P. 
Published: February 2018

SummaryWe introduce a smoothed particle hydrodynamics (SPH) concept for the stabilization of the interface between 2 fluids. It is demonstrated that the change in the pressure gradient across the interface leads to a force imbalance. This force imbalance is attributed to the particle approximation implicit to SPH. To stabilize the interface, a pressure gradient correction is proposed. In this approach, the multi‐fluid pressure gradients are related to the (gravitational and fluid) accelerations. This leads to a quasi‐buoyancy correction for hydrostatic (stratified) flows, which is extended to nonhydrostatic flows. The result is a simple density correction that involves no parameters or coefficients. This correction is included as an extra term in the SPH momentum equation. The new concept for the stabilization of the interface is explored in 5 case studies and compared with other multi‐fluid models. The first case is the stagnant flow in a tank: The interface remains stable up to density ratios of 1:1000 (typical for water and air), in combination with artificial wave speed ratios up to 1:4. The second and third cases are the Rayleigh‐Taylor instability and the rising bubble, where a reasonable agreement between SPH and level‐set models is achieved. The fourth case is an air flow across a water surface up to density ratios of 1:100, artificial wave speed ratios of 1:4, and high air velocities. The fifth case is about the propagation of internal gravity waves up to density ratios of 1:100 and artificial wave speed ratios of 1:4. It is demonstrated that the quasi‐buoyancy model may be used to stabilize the interface between 2 fluids up to high density ratios, with real (low) viscosities and more realistic wave speed ratios than achieved by other weakly compressible SPH multi‐fluid models. Real wave speed ratios can be achieved as long as the fluid velocities are not very high. Although the wave speeds may be artificial in many cases, correct and realistic wave speed ratios are essential in the modelling of heat transfer between 2 fluids (eg, in engineering applications such as gas turbines).
Spatial elongation of population receptive field profiles revealed by model‐free fMRI back‐projection
Authors: Merkel Christian , Hopf Jens‐Max , Schoenfeld Mircea Ariel 
Published: February 2018

AbstractEstimates of visual field topographies in human visual cortex obtained through fMRI traveling wave techniques usually provide the parameters of population receptive field (pRF) location (polar angle, eccentricity) and receptive field size. These parameters are obtained by fitting the recorded data to a standard model population receptive field. In this work, pRF profiles are measured directly by back‐projecting preprocessed fMRI time‐series to sweeps of a bar across the visual field in different angles. The current data suggest that the model‐free pRF profiles contain information not only about receptive field location and size but also about the pRF shape characteristics. The elongation (ellipticity) of pRFs decreases along the early visual hierarchy to a different degree for the ventral and the dorsal stream. Furthermore, ellipticity changes as a function of eccentricity. pRF orientation shows a high degree of collinearity with its angular position within the visual field. Using model‐free pRF measurements, the traveling wave technique provides additional characteristics of pRF topographies that are not restricted to size and provide robust measures within the single subject.
Exploring the rationale for combining ionizing radiation and immune checkpoint blockade in head and neck cancer
Authors: Morisada Megan , Chamberlin Michael , Allen Clint 
Published: February 2018

AbstractBackgroundThe ability of radiation to enhance antitumor immunity under specific experimental conditions is well established. Here, we explore preclinical data and the rationale for combining different radiation doses and fractions with immune checkpoint blockade immunotherapy.MethodsWe conducted a review of the literature.ResultsThe ability of high‐dose or hypofractionated radiation to enhance antitumor immunity resulting in additive or synergistic tumor control when combined with checkpoint blockade is well studied. Whether low‐dose daily fractionated radiation does the same is less well studied and available data suggests it may be immunosuppressive.ConclusionAlthough daily fractionated radiation is well established as the standard of care for the treatment of patients with head and neck cancer, how this radiation schema alters antitumor immunity needs further study. If the radiation doses and fractions alter antitumor immunity differently can have profound implications in the rational design of clinical trials investigating whether radiation can enhance response rates to immune checkpoint blockade.
Surface and subsurface water contributions to streamflow from a mesoscale watershed in complex mountain terrain
Authors: Zhang Qinghuan , Knowles John F. , Barnes Rebecca T. , Cowie Rory M. , Rock Nathan , Williams Mark W. 
Published: February 2018

AbstractAn understanding of surface and subsurface water contributions to streamflow is essential for accurate predictions of water supply from mountain watersheds that often serve as water towers for downstream communities. As such, this study used the end‐member mixing analysis technique to investigate source water contributions and hydrologic flow paths of the 264 km2 Boulder Creek Watershed, which drains the Colorado Front Range, USA. Four conservative hydrochemical tracers were used to describe this watershed as a 3 end‐member system, and tracer concentration reconstruction suggested that the application of end‐member mixing analysis was robust. On average from 2009 to 2011, snowmelt and rainwater from the subalpine zone and groundwater sampled from the upper montane zone contributed 54%, 22%, and 24% of the annual streamflow, respectively. These values demonstrate increased rainwater and decreased snow water contributions to streamflow relative to area‐weighted mean values derived from previous work at the headwater scale. Young water (2.3 ± 0.8 months) fractions of streamflow decreased from 18–22% in the alpine catchment to 8–10% in the lower elevation catchments and the watershed outlet with implications for subsurface storage and hydrological connectivity. These results contribute to a process‐based understanding of the seasonal source water composition of a mesoscale watershed that can be used to extrapolate headwater streamflow generation predictions to larger spatial scales.
A novel multimodal medical image fusion using sparse representation and modified spatial frequency
Authors: Aishwarya N. , Bennila Thangammal C. 
Published: February 2018

AbstractFusion of multimodal imaging data supports medical experts with ample information for better disease diagnosis and further clinical investigations. Recently, sparse representation (SR)‐based fusion algorithms has been gaining importance for their high performance. Building a compact, discriminative dictionary with reduced computational effort is a major challenge to these algorithms. Addressing this key issue, we propose an adaptive dictionary learning approach for fusion of multimodal medical images. The proposed approach consists of three steps. First, zero informative patches of source images are discarded by variance computation. Second, the structural information of remaining image patches is evaluated using modified spatial frequency (MSF). Finally, a selection rule is employed to separate the useful informative patches of source images for dictionary learning. At the fusion step, batch‐OMP algorithm is utilized to estimate the sparse coefficients. A novel fusion rule which measures the activity level in both spatial domain and transform domain is adopted to reconstruct the fused image with the sparse vectors and trained dictionary. Experimental results of various medical image pairs and clinical data sets reveal that the proposed fusion algorithm gives better visual quality and competes with existing methodologies both visually and quantitatively.
Live Imaging of Type I Collagen Assembly Dynamics in Osteoblasts Stably Expressing GFP and mCherry-Tagged Collagen Constructs
Authors: Lu Yongbo , Kamel-El Sayed Suzan A , Wang Kun , Tiede-Lewis LeAnn M , Grillo Michael A , Veno Patricia A , Dusevich Vladimir , Phillips Charlotte L , Bonewald Lynda F , Dallas Sarah L 
Published: February 2018

ABSTRACT

Type I collagen is the most abundant extracellular matrix protein in bone and other connective tissues and plays key roles in normal and pathological bone formation as well as in connective tissue disorders and fibrosis. Although much is known about the collagen biosynthetic pathway and its regulatory steps, the mechanisms by which it is assembled extracellularly are less clear. We have generated GFPtpz and mCherry-tagged collagen fusion constructs for live imaging of type I collagen assembly by replacing the α2(I)-procollagen N-terminal propeptide with GFPtpz or mCherry. These novel imaging probes were stably transfected into MLO-A5 osteoblast-like cells and fibronectin-null mouse embryonic fibroblasts (FN-null-MEFs) and used for imaging type I collagen assembly dynamics and its dependence on fibronectin. Both fusion proteins co-precipitated with α1(I)-collagen and remained intracellular without ascorbate but were assembled into α1(I) collagen-containing extracellular fibrils in the presence of ascorbate. Immunogold-EM confirmed their ultrastuctural localization in banded collagen fibrils. Live cell imaging in stably transfected MLO-A5 cells revealed the highly dynamic nature of collagen assembly and showed that during assembly the fibril networks are continually stretched and contracted due to the underlying cell motion. We also observed that cell-generated forces can physically reshape the collagen fibrils. Using co-cultures of mCherry- and GFPtpz-collagen expressing cells, we show that multiple cells contribute collagen to form collagen fiber bundles. Immuno-EM further showed that individual collagen fibrils can receive contributions of collagen from more than one cell. Live cell imaging in FN-null-MEFs expressing GFPtpz-collagen showed that collagen assembly was both dependent upon and dynamically integrated with fibronectin assembly. These GFP-collagen fusion constructs provide a powerful tool for imaging collagen in living cells and have revealed novel and fundamental insights into the dynamic mechanisms for the extracellular assembly of collagen. © 2018 American Society for Bone and Mineral Research.
Suppression of microRNA‐144‐3p attenuates oxygen–glucose deprivation/reoxygenation‐induced neuronal injury by promoting Brg1/Nrf2/ARE signaling
Authors: Li Yanru , Zhao Yongli , Cheng Mingkun , Qiao Yingjie , Wang Yongtao , Xiong Wancheng , Yue Wei 
Published: February 2018

AbstractAccumulating evidence has reported that microRNA‐144‐3p (miR‐144‐3p) is highly related to oxidative stress and apoptosis. However, little is known regarding its role in cerebral ischemia/reperfusion‐induced neuronal injury. Herein, our results showed that miR‐144‐3p expression was significantly downregulated in neurons following oxygen–glucose deprivation and reoxygenation (OGD/R) treatment. Overexpression of miR‐144‐3p markedly reduced cell viability, promoted cell apoptosis, and increased oxidative stress in neurons with OGD/R treatment, whereas downregulation of miR‐144‐3p protected neurons against OGD/R‐induced injury. Brahma‐related gene 1 (Brg1) was identified as a potential target gene of miR‐144‐3p. Moreover, downregulation of miR‐144‐3p promoted the nuclear translocation of nuclear factor erythroid 2‐related factor 2 (Nrf2) and increased antioxidant response element (ARE) activity. However, knockdown of Brg1 significantly abrogated the neuroprotective effects of miR‐144‐3p downregulation. Overall, our results suggest that miR‐144‐3p contributes to OGD/R‐induced neuronal injury in vitro through negatively regulating Brg1/Nrf2/ARE signaling.