bluuebunny/crossref_metadata_2025_split huggingface dataset:
Historical and projected trends in landscape drivers affecting carbon dynamics in Alaska
Authors: Pastick Neal J. , Duffy Paul , Genet Hélène , Rupp T. Scott , Wylie Bruce K. , Johnson Kristofer D. , Jorgenson M. Torre , Bliss Norman , McGuire A. David , Jafarov Elchin E. , Knight Joseph F. 
Published: April 2017

AbstractModern climate change in Alaska has resulted in widespread thawing of permafrost, increased fire activity, and extensive changes in vegetation characteristics that have significant consequences for socioecological systems. Despite observations of the heightened sensitivity of these systems to change, there has not been a comprehensive assessment of factors that drive ecosystem changes throughout Alaska. Here we present research that improves our understanding of the main drivers of the spatiotemporal patterns of carbon dynamics using in situ observations, remote sensing data, and an array of modeling techniques. In the last 60 yr, Alaska has seen a large increase in mean annual air temperature (1.7°C), with the greatest warming occurring over winter and spring. Warming trends are projected to continue throughout the 21st century and will likely result in landscape‐level changes to ecosystem structure and function. Wetlands, mainly bogs and fens, which are currently estimated to cover 12.5% of the landscape, strongly influence exchange of methane between Alaska's ecosystems and the atmosphere and are expected to be affected by thawing permafrost and shifts in hydrology. Simulations suggest the current proportion of near‐surface (within 1 m) and deep (within 5 m) permafrost extent will be reduced by 9–74% and 33–55% by the end of the 21st century, respectively. Since 2000, an average of 678 595 ha/yr was burned, more than twice the annual average during 1950–1999. The largest increase in fire activity is projected for the boreal forest, which could result in a reduction in late‐successional spruce forest (8–44%) and an increase in early‐successional deciduous forest (25–113%) that would mediate future fire activity and weaken permafrost stability in the region. Climate warming will also affect vegetation communities across arctic regions, where the coverage of deciduous forest could increase (223–620%), shrub tundra may increase (4–21%), and graminoid tundra might decrease (10–24%). This study sheds light on the sensitivity of Alaska's ecosystems to change that has the potential to significantly affect local and regional carbon balance, but more research is needed to improve estimates of land‐surface and subsurface properties, and to better account for ecosystem dynamics affected by a myriad of biophysical factors and interactions.
Mapping and exploring variation in post‐fire vegetation recovery following mixed severity wildfire using airborne LiDAR
Authors: Gordon Christopher E. , Price Owen F. , Tasker Elizabeth M. 
Published: April 2017

AbstractThere is a public perception that large high‐severity wildfires decrease biodiversity and increase fire hazard by homogenizing vegetation composition and increasing the cover of mid‐story vegetation. But a growing literature suggests that vegetation responses are nuanced. LiDARtechnology provides a promising remote sensing tool to test hypotheses about post‐fire vegetation regrowth because vegetation cover can be quantified within different height strata at fine scales over large areas. We assess the usefulness of airborne LiDARdata for measuring post‐fire mid‐story vegetation regrowth over a range of spatial resolutions (10 × 10 m, 30 × 30 m, 50 × 50 m, 100 × 100 m cell size) and investigate the effect of fire severity on regrowth amount and spatial pattern following a mixed severity wildfire in Warrumbungle National Park, Australia. We predicted that recovery would be more vigorous in areas of high fire severity, because park managers observed dense post‐fire regrowth in these areas. Moderate to strong positive associations were observed between LiDARand field surveys of mid‐story vegetation cover between 0.5–3.0 m. Thus our LiDARsurvey was an apt representation of on‐ground vegetation cover. LiDAR‐derived mid‐story vegetation cover was 22–40% lower in areas of low and moderate than high fire severity. Linear mixed‐effects models showed that fire severity was among the strongest biophysical predictors of mid‐story vegetation cover irrespective of spatial resolution. However much of the variance associated with these models was unexplained, presumably because soil seed banks varied at finer scales than our LiDARmaps. Dense patches of mid‐story vegetation regrowth were small (median size 0.01 ha) and evenly distributed between areas of low, moderate and high fire severity, demonstrating that high‐severity fires do not homogenize vegetation cover. Our results are relevant for ecosystem conservation and fire management because they: indicate that native vegetation are responsive and resilient to high‐severity fire, and show the usefulness of remote sensing tools such as LiDARto monitor post‐fire vegetation recovery over large areas in situ.
Cytocompatibility assessment of Ti‐Zr‐Pd‐Si‐(Nb) alloys with low Young's modulus, increased hardness, and enhanced osteoblast differentiation for biomedical applications
Authors: Blanquer Andreu , Musilkova Jana , Barrios Leonardo , Ibáñez Elena , Vandrovcova Marta , Pellicer Eva , Sort Jordi , Bacakova Lucie , Nogués Carme 
Published: April 2017

AbstractTi‐based alloys have increased importance for biomedical applications due to their excellent properties. In particular, the two recently developed TiZrPdSi(Nb) alloys, with a predominant β‐Ti phase microstructure, have good mechanical properties, such as a relatively low Young's modulus and high hardness. In the present work, the cytocompatibility of these alloys was assessed using human osteoblast‐like Saos‐2 cells. Cells grown on the alloys showed larger spreading areas (more than twice) and higher vinculin content (nearly 40% increment) when compared with cells grown on glass control surfaces, indicating a better cell adhesion. Moreover, cell proliferation was 18% higher for cells growing on both alloys than for cells growing on glass and polystyrene control surfaces. Osteogenic differentiation was evaluated by quantifying the expression of four osteogenic genes (osteonectin, osteocalcin, osteopontin, and bone sialoprotein), the presence of three osteogenic proteins (alkaline phosphatase, collagen I, and osteocalcin) and the activity of alkaline phosphatase at different time‐points. The results demonstrated that TiZrPdSi and TiZrPdSiNb alloys enhance osteoblast differentiation, and that cells grown on TiZrPdSiNb alloy present higher levels of some late osteogenic markers during the first week in culture. These results suggest that the TiZrPdSi(Nb) alloys can be considered as excellent candidates for orthopaedical uses. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 834–842, 2018.
Retracted: Suppression of Basic Fibroblast Growth Factor Expression by Antisense Oligonucleotides Inhibits Neural Stem Cell Proliferation and Differentiation in Rat models With Focal Cerebral Infarction
Authors: Li Chao , Che Li‐He , Shi Lei , Yu Jin‐Lu 
Published: April 2017

ABSTRACTThis study is designed to investigate the role of basic fibroblast growth factor (bFGF) antisense oligonucleotide (ASODN) on the proliferation and differentiation of neural stem cells (NSCs) in rat models with focal cerebral infarction (CI). Seventy‐five Sprague‐Dawlay (SD) rats were randomly divided into the control, sham, middle cerebral artery occlusion (MCAO), MCAO + nonsense oligonucleotide (NODN), and MCAO + ASODN groups. Proliferation and differentiation of NSCs were detected by bromodeoxyuridine (BrdU) and immunofluorescence staining, respectively. ELISA was performed to detect the expressions of endogenous factors that include insulin‐like growth factor 1 (IGF‐1), glial cell line derived neurotrophic factor (GDNF), brain‐derived neurotrophic factor (BDNF), transforming growth factor‐α1 (TGF‐α1), bFGF, and nerve growth factor (NGF). Results show significant neurological deficits and focal CI in the MCAO and MCAO + NODN groups. An obvious increase of NSC proliferation, reactive proliferation of astrocytes in CI areas, differentiation of newly proliferated NSCs into mature neuronal cells, and expressions of endogenous growth factors exhibited in the MCAO, MCAO + NODN and MCAO + ASODN groups. Compared to the MCAO and MACO + NODN groups, the MCAO + ASODN group showed a significant decrease NSC proliferation and differentiation in CI areas as well as decrease expressions of endogenous growth factors. These findings may offer insight to help us understand more as to how bFGF ASODN can effectively suppress the proliferation and differentiation of NSCs. These findings are expected to help contribute to research for new targets in the treatment of focal CI. J. Cell. Biochem. 118: 3875–3882, 2017. © 2017 Wiley Periodicals, Inc.
The Non‐Peptide Vasopressin V1b Receptor Antagonist, SSR149415, Ameliorates Spermatogenesis Function in a Mouse Model of Chronic Social Defeat Stress
Authors: Wang Bin , Zhou Jian , Zhuang Yan‐Yan , Wang Liang‐Liang , Pu Jin‐Xian , Huang Yu‐Hua , Xia Fei , Lv Jin‐Xing 
Published: April 2017

ABSTRACTTo determine the effects of SSR149415 on testis and spermatogenesis in male mice subjected to chronic social defeat stress, C57BL/6 male mice were divided into two groups: Control and Stress. Then Stress group was subdivided into four subgroups administered water, SSR149415 (1 mg/kg/day), SSR149415 (10 mg/kg/day), SSR149415 (30 mg/kg/day), respectively. The behavioral alterations revealed by social interaction test and open field test were measured. The physical indices, including body weight and gonad weight (testis and epididymis) as well as testis/body weight and cauda epididymis/body weight were detected. Serum hormones, including testosterone, luteinizing hormone (LH), and follicle‐stimulating hormone (FSH) were determined. Sperm count and abnormality as well as testicular histology structure were assessed. The germ cells apoptosis were also evaluated. Chronic social defeat stress‐induced behavioral abnormality, as well as gonad atrophy (testis and epididymis) was significantly alleviated in stressed male mice exposed to SSR149415. Regressed serum testosterone levels and elevated serum FSH and LH levels exhibited by stressed male mice were observably reversed following SSR149415 administration. Chronic social defeat stress‐induced damage in testicular histology structure and semen quality were also improved after SSR149415 administration. In addition, SSR149415 significantly reversed chronic social defeat stress‐induced germ cells apoptosis. Overall, we provide clear evidence indicating the amelioration of chronic social defeat stress‐induced behavioral abnormality and testicular dysfunction via SSR149415, promoting the development of drug‐directed therapy against this disease. J. Cell. Biochem. 118: 3891–3898, 2017. © 2017 Wiley Periodicals, Inc.
Runt‐Related Transcription Factor 2 (Runx2) Is Responsible for Galectin‐3 Overexpression in Human Thyroid Carcinoma
Authors: Kaptan Engin , Sancar Bas Serap , Sancakli Aylin , Aktas Hatice Gumushan , Bayrak Bertan Boran , Yanardag Refiye , Bolkent Sehnaz 
Published: April 2017

ABSTRACTRunx2 promotes metastatic ability of cancer cells by directly activating some of the mediators regarding malignancy. Galectin‐3 (Gal‐3) extensively expressed in normal and transformed cells and it is responsible for many cellular processes. In this study, we aimed to investigate whether there is any relationship between runx2 transcription factor and regulation of galectin‐3 expression in different human thyroid carcinoma cell lines. To show effects of runx2 transcription factor on gal‐3 expression, we developed runx2 knockdown model in the thyroid carcinoma cell lines; anaplastic 8505C and 8305C and, papillary TPC‐1 and follicular FTC‐133 by using siRNA transfection. We analyzed the protein expressions and mRNA levels of gal‐3 and MMP2/9 in the runx2‐silenced cell lines using Western blotting, qPCR, and fluorescent microscopy. Our results showed that mRNA expression levels of gal‐3 and MMP2/9 were downregulated in runx2‐silenced cell lines. In this investigation, we revealed that regulation of gal‐3 expression was strongly correlated with runx2 transcription factor in human thyroid carcinoma. Considering the contribution of human gal‐3 in collaboration with MMP2/9 to the malignant characters of many cancers, regulation of their expressions through runx2 seems like one of the key regulatory mechanism for malignant potential of human thyroid carcinoma. Accordingly, runx2 transcription factor inhibitors can be a potential target in order to prevent gal‐3 mediated malignancy of human thyroid carcinoma. J. Cell. Biochem. 118: 3911–3919, 2017. © 2017 Wiley Periodicals, Inc.
Valve mediated hemodynamics and their association with distal ascending aortic diameter in bicuspid aortic valve subjects
Authors: Raghav Vrishank , Barker Alex J. , Mangiameli Daniel , Mirabella Lucia , Markl Michael , Yoganathan Ajit P. 
Published: April 2017

PurposeValve mediated hemodynamics have been postulated to contribute to pathology of the ascending aorta (AAo). The objective of this study is to assess the association of aortic valve morphology and hemodynamics with downstream AAo size in subjects with bicuspid aortic valve (BAV) disease.Materials and MethodsFour‐dimensional flow MRI at 1.5 or 3 Tesla was used to evaluate the hemodynamics in the proximal AAo of 52 subjects: size‐matched controls with tricuspid aortic valves (n = 24, mid ascending aorta [MAA] diameter = 38.0 ± 4.9 mm) and BAV patients with aortic dilatation (n = 14 right and left coronary leaflet fusion [RL]‐BAV, MAA diameter = 38.1 ± 5.3 mm; n = 14 right and noncoronary leaflet fusion [RN]‐BAV, MAA diameter = 36.5 ± 6.6 mm). A validated semi‐automated technique was used to evaluate hemodynamic metrics (flow angle, flow displacement, and jet quadrant) and valve morphology (orifice circularity) for all subjects. Regression analysis of these metrics to AAo diameter was performed.ResultsRN‐BAV subjects displayed a stronger correlation between hemodynamic metrics in the proximal AAo with diameter in the distal AAo compared with size‐matched tricuspid aortic valve (TAV) controls and RL‐BAV subjects. The distal AAo diameter was found to be strongly correlated to the upstream flow displacement (R2adjusted = 0.75) and flow angle (R2adjusted = 0.66) measured at the sino‐tubular junction (STJ). Orifice circularity was also strongly correlated (R2adjusted = 0.53) to the distal AAo diameter in RN‐BAV subjects. For TAV controls and RL‐BAV subjects, correlations were weaker (R2adjusted < 0.2).ConclusionHemodynamics in the STJ were strongly correlated to the distal AAo diameter for the RN‐BAV subjects. Hemodynamic metrics were more strongly correlated to the downstream aortic size when compared with valve morphology metrics.Level of Evidence: 3Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2018;47:246–254.
Prediction of normal bone anatomy for the planning of corrective osteotomies of malunited forearm bones using a three‐dimensional statistical shape model
Authors: Mauler Flavien , Langguth Christoph , Schweizer Andreas , Vlachopoulos Lazaros , Gass Tobias , Lüthi Marcel , Fürnstahl Philipp 
Published: April 2017

ABSTRACTCorrective osteotomies of the forearm based on 3D computer simulation using contralateral anatomy as a reconstruction template is an approved method. Limitations are existing considerable differences between left and right forearms, and that a healthy contralateral anatomy is required. We evaluated if a computer model, not relying on the contralateral anatomy, may replace the current method by predicting the pre‐traumatic healthy shape. A statistical shape model (SSM) was generated from a set of 59 CT scans of healthy forearms, encoding the normal anatomical variations. Three different configurations were simulated to predict the pre‐traumatic shape with the SSM (cross‐validation). In the first two, only the distal or proximal 50% of the radius were considered as pathological. In a third configuration, the entire radius was assumed to be pathological, only the ulna being intact. Corresponding experiments were performed with the ulna. Accuracy of the prediction was assessed by comparing the predicted bone with the healthy model. For the radius, mean rotation accuracy of the prediction between 2.9 ± 2.2° and 4.0 ± 3.1° in pronation/supination, 0.4 ± 0.3° and 0.6 ± 0.5° in flexion/extension, between 0.5 ± 0.3° and 0.5 ± 0.4° in radial‐/ulnarduction. Mean translation accuracy along the same axes between 0.8 ± 0.7 and 1.0 ± 0.8 mm, 0.5 ± 0.4 and 0.6 ± 0.4 mm, 0.6 ± 0.4 and 0.6 ± 0.5 mm, respectively. For the ulna, mean rotation accuracy between 2.4 ± 1.9° and 4.7 ± 3.8° in pronation/supination, 0.3 ± 0.3° and 0.8 ± 0.6° in flexion/extension, 0.3 ± 0.2° and 0.7 ± 0.6° in radial‐/ulnarduction. Mean translation accuracy between 0.6 ± 0.4 mm and 1.3 ± 0.9 mm, 0.4 ± 0.4 mm and 0.7 ± 0.5 mm, 0.5 ± 0.4 mm and 0.8 ± 0.6 mm, respectively. This technique provided high accuracy, and may replace the current method, if validated in clinical studies. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2630–2636, 2017.
A “Mitsubishi emblem” tetrauclear aluminum complex containing two unsymmetric N2O2‐ligands and a symmetric NO3‐ligand as initiator for polymerization of rac‐lactide
Authors: Hu Minggang , Wang Fugui , Han Fuzhong , Deng Qigang , Ma Wenhui , Yan Hailong , Dong Guohua , Song Weiming 
Published: April 2017

ABSTRACTA novel hydroxy‐, methoxy‐, and phenoxy‐bridge “Mitsubishi emblem” tetranuclear aluminum complex (1) is synthesized from an unsymmetric amine‐pyridine‐bis(phenol) N2O2‐ligand (H2L1) and a symmetric amine‐tris(phenol) NO3‐ligand (H2L2). Two same configuration chiral nitrogen atoms are formed in the tetranuclear Al complex upon coordination of the unsymmetric tertiary amine ligand to central Al. Complex 1 initiates controlled ring‐opening polymerization (ROP) of rac‐lactide and afford polylactide (PLA) with narrow molecular weight distributions (Mw/Mn = 1.05–1.19). The analysis of 1H NMR spectra of the oligomer indicates that the methoxy group is the initiating group and the ring‐opening polymerization of lactide follows a coordination‐insertion mechanism. The Homonuclear decoupled 1H NMR spectroscopy suggests the isotactic‐rich chains is preferentially formed in PLA. The study on kinetics of the ROP of lactide reveals the homopropagation rate is higher than the cross‐propagation rate, which is in agreement with the observed isotactic selectivity in the ROP of rac‐lactide. The stereochemistry of the polymerization was also supported by activation parameters. The introduction of unsymmetric ligand H2L1 has an effect on stereoslectivity of polymerization. This result may be of interest for the design of multinuclear metal complex catalysts containing functionalized ligands. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2084–2091
Spontaneous evolution of nanostructures by light‐driven growth of micelles obtained from in situ nanoparticlization of conjugated polymers
Authors: Kang Eun‐Hye , Yang Sanghee , Yu So Young , Kim Jeongeun , Choi Tae‐Lim 
Published: April 2017

ABSTRACTTo simplify processes to produce self‐assembled nanostructures from polymeric materials, there have been several attempts for in situ self‐assembly of block copolymers. As one of these strategies, we developed the in situ nanoparticlization of conjugated polymers (INCP) process to construct various stable nanostructures without postsynthetic treatments. To get spontaneous mesoscopic evolution of the nanostructures obtained by INCP, a new strategy utilizing a unique conformational change of the conjugated polymer is reported herein. The combination of living ring‐opening olefin metathesis polymerization (ROMP) and cyclopolymerization produced block and gradient copolymers through one‐pot or one‐shot polymerization, which initially formed spherical micelles via INCP. Then, the core block of the micelle stiffened through a coil‐to‐rod conformational change by simple aging in organic solvents because of cis‐to‐trans isomerization of the conjugated polymer under light. Subsequently, this enhanced the π‐π interaction among the cores, and eventually promoted the growth of stable nanostructures from spheres to 1D‐nanocaterpillars or 2D‐sheet‐like architectures. This time‐dependent macroscopic evolution provides deeper insight into the production of a variety of kinetically fixed nano‐ and mesoscale structures through INCP. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3058–3066
Theoretical studies for forecasting the power conversion efficiencies of polymer‐based organic photovoltaic cells
Authors: Zanlorenzi Cristiano , Akcelrud Leni 
Published: April 2017

ABSTRACTModifying the electron‐withdrawing capability in donor–acceptor conjugated copolymers allows designing new polymers with better optical properties. These materials have been successfully applied in bulk heterojunction solar cell devices, and recently a great progress in the enhancement of power conversion efficiencies (PCE) has been achieved. In 2006 Scharber proposed a design rule to obtain PCE values over 10%, optimizing the orbital energy levels of the donor material. The present work proposes a methodology capable to predict theoretically the best efficiencies imparted by a group of 65 conjugated monomeric units selected from the literature, generating 2080 possible DA combinations. The geometries, frontier levels and optical properties were estimated by DFT methods. Based on the results, it was possible to predict the PCE of the most promising 22 copolymers. The results of the calculations indicated that several polymers investigated showed the predicted PCE between 9% and 10%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 919–927
Crystallization and melting of isotactic polypropylene crystallized from quiescent melt and stress‐induced localized melt
Authors: Lu Ying , Wang Yaotao , Chen Ran , Men Yongfeng 
Published: April 2017

ABSTRACTTemperature dependency of crystalline lamellar thickness during crystallization and subsequent melting in isotactic polypropylene crystallized from both quiescent molten state and stress‐induced localized melt was investigated using small angle X‐ray scattering technique. Both cases yield well‐defined crystallization lines where inverse lamellar thickness is linearly dependent on crystallization temperature with the stretching‐induced crystallization line shifted slightly to smaller thickness direction than the isothermal crystallization one indicating both crystallization processes being mediated a mesomorphic phase. However, crystallites obtained via different routes (quiescent melt or stress‐induced localized melt) show different melting behaviors. The one from isothermal crystallization melted directly without significant changing in lamellar thickness yielding well‐defined melting line whereas stress‐induced crystallites followed a recrystallization line. Such results can be associated with the different extent of stabilization of crystallites obtained through different crystallization routes. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 957–963