bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of long‐term Holocene soil erosion rates in Polish loess areas using sedimentary archives from closed depressions
Authors: Kołodyńska‐Gawrysiak Renata , Poesen Jean , Gawrysiak Leszek 
Published: November 2017

AbstractSoil erosion is a particularly important problem in the loess areas of Central Europe. Numerous studies of past and present soil erosion based on colluvial sediments have so far been conducted. The main problem is the fact that colluvia usually do not represent the complete sedimentation record. Closed depressions (CDs) collect all colluvial sediments from their catchment, therefore, constitute sediment stores enabling the calculation of soil erosion rates.Colluvial sediments and fossil soils, infilling four CDs in the Polish loess belt, were OSL and C‐14 dated. Human settlements near the studied CDs were analyzed. Phases of soil erosion and colluviation from the Neolithic (5400–2900 bc), from the Middle Bronze Age to the Early Iron Age (1600–0 bc), and from the Early Middle Ages to Modern Times (500 AD until today) were documented within the CDs studied. Phases of low soil erosion rate and pedogenesis occurred from the Late Vistulian to the Early Neolithic and from the Iron Age to Early Middle Ages. This study reveals that these phases are not synchronous with the soil erosion phases in Central Europe, as the latter mainly occurred in the Bronze Age, Roman Period and Middle Ages. The obtained soil erosion rates were compared with erosion rates in different areas of Central Europe. This study indicates that in loess regions with long‐term agricultural land use, mean erosion rates (i.e. 3.7–5.9 t ha‐1 yr‐1) from the Middle Ages to Modern Times were ten times higher than during the entire prehistoric period (0.39–0.67 t ha‐1 yr‐1). The mean soil erosion rates for forested CDs was 0.24–0.74 t ha‐1 yr‐1.Soil erosion phases are most probably caused by human activities (i.e. land use change) but the early Holocene erosion phase (7.96 +/‐ 0.67 kyr) could have been induced by a climatic fluctuation (e.g. a 8.2 kyr Bond event). Copyright © 2018 John Wiley & Sons, Ltd.
Metal‐coordinated epoxy polymers with suppressed combustibility. Preparation technology, thermal degradation, and combustibility test of new epoxy‐amine polymers containing the curing agent with chelated copper(II) carbonate
Authors: Lavrenyuk Helen , Kochubei Victoria , Mykhalichko Oleg , Mykhalichko Borys 
Published: November 2017

SummaryThe diethylenetriamine chelate complex of copper(II) carbonate—DETA‐CuCO3 (a fire retardant hardener of epoxy resins)—and the CuCO3‐containing epoxy‐amine polymers—DGEBA/DETA‐CuCO3(6), DGEBA/DETA‐CuCO3(12), DGEBA/DETA‐CuCO3(40), and DGEBA/DETA‐CuCO3(80) with suppressed combustibility—have been obtained in the DETA‐DGEBA‐CuCO3 system (DETA and DGEBA are diethylenetriamine and bisphenol A diglycidyl ether, respectively). The DETA‐CuCO3 chelate complex was characterized by X‐ray powder diffraction, infrared spectra, and thermal analysis. The thermal gravimetric analysis results have revealed that thermal destruction of DETA‐CuCO3 was finished at 400°С, and the maximal temperature of the combustion gases amounted to 520°С. The thermal behavior and combustibility of the CuCO3‐containing epoxy‐amine polymers were studied using thermal analysis and “Ceramic tube” (CT) method. Thermal gravimetric analysis confirms that incorporation of the DETA‐CuCO3 into DGEBA appreciably heightens the thermal stability and antiflammability of the CuCO3‐containing epoxy‐amine polymers. Results of CT measurement reveal that maximal temperature of the combustion gases under burning of the DGEBA/DETA‐CuCO3(12) sample in comparison with unmodified epoxy‐amine polymer (DGEBA/DETA) is lowered on 219°С and the loss of weight is decreased on 20.5 wt%. According to ASTM 635‐14, ASTM D2863‐13, and ASTM D1929‐16, the flame propagation rate, limiting oxygen index, and temperatures of ignition and self‐ignition have been measured for the elaborated polymer samples.
Predictive accuracy of combined genetic and environmental risk scores
Authors: Dudbridge Frank , Pashayan Nora , Yang Jian 
Published: November 2017

ABSTRACTThe substantial heritability of most complex diseases suggests that genetic data could provide useful risk prediction. To date the performance of genetic risk scores has fallen short of the potential implied by heritability, but this can be explained by insufficient sample sizes for estimating highly polygenic models. When risk predictors already exist based on environment or lifestyle, two key questions are to what extent can they be improved by adding genetic information, and what is the ultimate potential of combined genetic and environmental risk scores? Here, we extend previous work on the predictive accuracy of polygenic scores to allow for an environmental score that may be correlated with the polygenic score, for example when the environmental factors mediate the genetic risk. We derive common measures of predictive accuracy and improvement as functions of the training sample size, chip heritabilities of disease and environmental score, and genetic correlation between disease and environmental risk factors. We consider simple addition of the two scores and a weighted sum that accounts for their correlation. Using examples from studies of cardiovascular disease and breast cancer, we show that improvements in discrimination are generally small but reasonable degrees of reclassification could be obtained with current sample sizes. Correlation between genetic and environmental scores has only minor effects on numerical results in realistic scenarios. In the longer term, as the accuracy of polygenic scores improves they will come to dominate the predictive accuracy compared to environmental scores.
Using imputed genotype data in the joint score tests for genetic association and gene–environment interactions in case‐control studies
Authors: Song Minsun , Wheeler William , Caporaso Neil E. , Landi Maria Teresa , Chatterjee Nilanjan 
Published: November 2017

ABSTRACTGenome‐wide association studies (GWAS) are now routinely imputed for untyped single nucleotide polymorphisms (SNPs) based on various powerful statistical algorithms for imputation trained on reference datasets. The use of predicted allele counts for imputed SNPs as the dosage variable is known to produce valid score test for genetic association. In this paper, we investigate how to best handle imputed SNPs in various modern complex tests for genetic associations incorporating gene–environment interactions. We focus on case‐control association studies where inference for an underlying logistic regression model can be performed using alternative methods that rely on varying degree on an assumption of gene–environment independence in the underlying population. As increasingly large‐scale GWAS are being performed through consortia effort where it is preferable to share only summary‐level information across studies, we also describe simple mechanisms for implementing score tests based on standard meta‐analysis of “one‐step” maximum‐likelihood estimates across studies. Applications of the methods in simulation studies and a dataset from GWAS of lung cancer illustrate ability of the proposed methods to maintain type‐I error rates for the underlying testing procedures. For analysis of imputed SNPs, similar to typed SNPs, the retrospective methods can lead to considerable efficiency gain for modeling of gene–environment interactions under the assumption of gene–environment independence. Methods are made available for public use through CGEN R software package.
A unified partial likelihood approach for X‐chromosome association on time‐to‐event outcomes
Authors: Xu Wei , Hao Meiling 
Published: November 2017

AbstractThe expression of X‐chromosome undergoes three possible biological processes: X‐chromosome inactivation (XCI), escape of the X‐chromosome inactivation (XCI‐E), and skewed X‐chromosome inactivation (XCI‐S). Although these expressions are included in various predesigned genetic variation chip platforms, the X‐chromosome has generally been excluded from the majority of genome‐wide association studies analyses; this is most likely due to the lack of a standardized method in handling X‐chromosomal genotype data. To analyze the X‐linked genetic association for time‐to‐event outcomes with the actual process unknown, we propose a unified approach of maximizing the partial likelihood over all of the potential biological processes. The proposed method can be used to infer the true biological process and derive unbiased estimates of the genetic association parameters. A partial likelihood ratio test statistic that has been proved asymptotically chi‐square distributed can be used to assess the X‐chromosome genetic association. Furthermore, if the X‐chromosome expression pertains to the XCI‐S process, we can infer the correct skewed direction and magnitude of inactivation, which can elucidate significant findings regarding the genetic mechanism. A population‐level model and a more general subject‐level model have been developed to model the XCI‐S process. Finite sample performance of this novel method is examined via extensive simulation studies. An application is illustrated with implementation of the method on a cancer genetic study with survival outcome.
Phagocytic clearance of presynaptic dystrophies by reactive astrocytes in Alzheimer's disease
Authors: Gomez‐Arboledas Angela , Davila Jose C. , Sanchez‐Mejias Elisabeth , Navarro Victoria , Nuñez‐Diaz Cristina , Sanchez‐Varo Raquel , Sanchez‐Mico Maria Virtudes , Trujillo‐Estrada Laura , Fernandez‐Valenzuela Juan Jose , Vizuete Marisa , Comella Joan X. , Galea Elena , Vitorica Javier , Gutierrez Antonia 
Published: November 2017

AbstractReactive astrogliosis, a complex process characterized by cell hypertrophy and upregulation of components of intermediate filaments, is a common feature in brains of Alzheimer's patients. Reactive astrocytes are found in close association with neuritic plaques; however, the precise role of these glial cells in disease pathogenesis is unknown. In this study, using immunohistochemical techniques and light and electron microscopy, we report that plaque‐associated reactive astrocytes enwrap, engulf and may digest presynaptic dystrophies in the hippocampus of amyloid precursor protein/presenilin‐1 (APP/PS1) mice. Microglia, the brain phagocytic population, was apparently not engaged in this clearance. Phagocytic reactive astrocytes were present in 35% and 67% of amyloid plaques at 6 and 12 months of age, respectively. The proportion of engulfed dystrophic neurites was low, around 7% of total dystrophies around plaques at both ages. This fact, along with the accumulation of dystrophic neurites during disease course, suggests that the efficiency of the astrocyte phagocytic process might be limited or impaired. Reactive astrocytes surrounding and engulfing dystrophic neurites were also detected in the hippocampus of Alzheimer's patients by confocal and ultrastructural analysis. We posit that the phagocytic activity of reactive astrocytes might contribute to clear dysfunctional synapses or synaptic debris, thereby restoring impaired neural circuits and reducing the inflammatory impact of damaged neuronal parts and/or limiting the amyloid pathology. Therefore, potentiation of the phagocytic properties of reactive astrocytes may represent a potential therapy in Alzheimer's disease.
Advanced service offshore outsourcing: Exploring the determinants of capability development in emerging market firms
Authors: Brandl Kristin , Jensen Peter D. Ørberg , Lind Manya Jaura 
Published: November 2017

Research Summary: We analyze the effect of offshored service task types on the development of capabilities in emerging market service provider firms. Using multiple case studies, we find that, dependent on task interdependent service types, implying different client interactions (firm‐external determinants), organizational capabilities are developed. More specifically, reciprocal task interdependent services generate human capital and management capabilities, while sequential task interdependent services generate organizational capital and management capabilities. Moreover, we find a relationship between the capabilities, where the deficient development of one capability can be mitigated by the development of another capability (firm‐internal determinants). Grounded in organization and service production theory, the article contributes to the thematic literature on service offshoring and the literature on organizational capabilities, with a particular focus on emerging market firms.
Managerial Summary: Offshore outsourcing of advanced services is contributing to the development of capabilities for client firms, but is also expected to benefit service provider firms from emerging markets. Thus, we study how offshore outsourcing of services contributes to the development of these capabilities for service provider firms. We find that the characteristics of the services, which are causing different interactions with the client, help the firm develop a variety of capabilities. These capabilities affect the management, employees, and organization of service provider firms. Although the developed competencies are not a solution for all business development challenges of emerging market firms, the implications of this study could lead to competitive advantages for the firms if fully explored and exploited.
Angiotensin‐1‐converting enzyme inhibition, antioxidant activity, and modulation of cerebral Na+/K+ ATPase by free phenolics of African locust bean (Parkia biglobosa)
Authors: Komolafe Kayode , Akinmoladun Afolabi C. , Komolafe Titilope R. , Olaleye Mary T. , Boligon Aline A. , Akindahunsi Akintunde A. , Rocha Joao B.T. 
Published: November 2017

AbstractAimsTo investigate the antioxidant activities and effects of free phenols (FPPB) and bound phenols (BPPB) of Parkia biglobosa leaves on some enzymes of neuro‐cardiovascular relevance.Methods and ResultsHPLC‐DAD fingerprinting of FPPB and BPPB, and the antihemolytic, radical (1,1‐diphenyl‐2 picrylhydrazyl, DPPH; 2,2‐azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid), ABTS) scavenging and ferric reducing antioxidant properties of extracts, were assessed. In addition, the effects of the phenolics on angiotensin‐1‐converting enzyme (ACE), cerebral acetylcholinesterase/butyrylcholinesterase (AChE/BuChE), and Na+/K+ATPase were determined in vitro. FPPB was more potent than BPPB in terms of ABTS (EC50:4.06 ± 0.3 vs 24.07 ± 2.1 μg/mL) and DPPH (EC50:3.82 ± 0.2 vs 10.22 ± 0.1 μg/mL) radicals scavenged, respectively. The free phenolic extract was a better DPPH. scavenger than ascorbic acid (EC50 = 12.58 ± 0.4 μg/mL; DPPH reference) and compared well with Trolox (EC50:4.44 ± 0.08 μg/mL; ABTS reference). The anti‐hemolytic effect of FPPB (36%) and BPPB (53%) was highest at 15 μg/mL but lower than that recorded for ascorbic acid (67% at 10 μg/mL). Even though FPPB (IC50 = 15.35 ± 4.0 μg/mL) and BPPB (IC50 = 46.85 ± 3.3 μg/mL) showed considerably lower ACE‐inhibitory effect than ramipril (IC50:0.173 ± 0.04 μg/mL), both extracts demonstrated dose‐dependent, significant (p < 0.01/p < 0.05) inhibition of the enzyme. FPPB increased cerebral Na+/K+ATPase activity but neither phenolic extract affects cerebral AChE/BuChE activities. HPLC‐DAD revealed catechin, caffeic acid, and quercetin, respectively, as the major phenolics (mg/g) in FPPB (29.85, 30.29, and 17.10) and BPPB (32.70, 30.51, and 19.25).ConclusionThe effects of P biglobosa on ACE and cerebral ATPase are related to its constituent phenolics. ACE inhibition could be an important mechanism underlying the documented hypotensive effect of the plant.
Microvascular characteristics of the acoustic fats: Novel data suggesting taxonomic differences between deep and shallow‐diving odontocetes
Authors: Gabler Molly K. , Gay D. Mark , Westgate Andrew J. , Koopman Heather N. 
Published: November 2017

AbstractOdontocetes have specialized mandibular fats, the extramandibular (EMFB) and intramandibular fat bodies (IMFB), which function as acoustic organs, receiving and channeling sound to the ear during hearing and echolocation. Recent strandings of beaked whales suggest that these fat bodies are susceptible to nitrogen (N2) gas embolism and empirical evidence has shown that the N2 solubility of these fat bodies is higher than that of blubber. Since N2 gas will diffuse from blood into tissue at any blood/tissue interface and potentially form gas bubbles upon decompression, it is imperative to understand the extent of microvascularity in these specialized acoustic fats so that risk of embolism formation when diving can be estimated. Microvascular density was determined in the EMFB, IMFB, and blubber from 11 species representing three odontocete families. In all cases, the acoustic tissues had less (typically 1/3 to 1/2) microvasculature than did blubber, suggesting that capillary density in the acoustic tissues may be more constrained than in the blubber. However, even within these constraints there were clear phylogenetic differences. Ziphiid (Mesoplodon and Ziphius, 0.9 ± 0.4% and 0.7 ± 0.3% for EMFB and IMFB, respectively) and Kogiid families (1.2 ± 0.2% and 1.0 ± 0.01% for EMFB and IMFB, respectively) had significantly lower mean microvascular densities in the acoustic fats compared to the Delphinid species (Tursiops, Grampus, Stenella, and Globicephala, 1.3 ± 0.3% and 1.3 ± 0.3% for EMFB and IMFB, respectively). Overall, deep‐diving beaked whales had less microvascularity in both mandibular fats and blubber compared to the shallow‐diving Delphinids, which might suggest that there are differences in the N2 dynamics associated with diving regime, phylogeny, and tissue type. These novel data should be incorporated into diving physiology models to further understand potential functional disruption of the acoustic tissues due to changes in normal diving behavior.
Global transition of human serum albumin to prefibrillar aggregates induced by temsirolimus: Insight into implications of anti‐renal cancer drug
Authors: Shamsi Anas , Ahmed Azaj , Bano Bilqees 
Published: November 2017

AbstractIn our study, we have characterized the prefibrillar aggregates of human serum albumin (HSA) induced by temsirolimus, anti‐renal cancer drug. Molecular docking was retorted to confirm binding of HSA and temsirolimus. Temsirolimus caused the structural transition of native HSA to non‐native species after prolonged incubation of 20 days. These non‐native species were characterized as prefibrillar aggregates as evident by decreased intrinsic fluorescence and enhanced 8‐anilino‐1‐naphthalene‐sulphonic acid (ANS) fluorescence. Further, enhanced thioflavin T fluorescence and shift in congo red (CR) spectra of temsirolimus‐incubated HSA as compared to native HSA are suggestive of global transition of HSA in presence of temsirolimus towards prefibrillar aggregates. Circular dichroism spectroscopy revealed α to β transition upon prolonged incubation with temsirolimus suggesting the formation of prefibrillar aggregates as aggregates are known to possess high β content. Scanning electron microscopy confirmed these non‐native species to be prefibrillar aggregates evident by observed sheath‐like structures. Comet assay was retorted to confirm genotoxic nature of these prefibrillar aggregates; DNA damage was observed for temsirolimus‐incubated HSA confirming the genotoxic nature of prefibrillar aggregates. These prefibrillar aggregates are observed at heart of many pathological conditions, thus making our study clinically significant.
Developing and validating a multivariable prediction model to improve the diagnostic accuracy in determination of cervical versus endometrial origin of uterine adenocarcinomas: A prospective MR study combining diffusion‐weighted imaging and spectroscopy
Authors: Lin Gigin , Lin Yu‐Chun , Wu Ren‐Chin , Yang Lan‐Yan , Lu Hsin‐Ying , Tsai Shang‐Yueh , Huang Yu‐Ting , Huang Yen‐Ling , Lu Kuan‐Ying , Ng Koon‐Kwan , Yen Tzu‐Chen , Chao Angel , Lai Chyong‐Huey , Hong Ji‐Hong 
Published: November 2017

BackgroundA triage test to assist clinical decision‐making on choosing primary chemoradiation for cervical carcinomas or primary surgery for endometrial carcinomas is important.Purpose or HypothesisTo develop and validate a multiparametric prediction model based on MR imaging and spectroscopy in distinguishing adenocarcinomas of uterine cervical or endometrial origin.Study TypeProspective diagnostic accuracy study.PopulationEighty‐seven women: 25 cervical and 62 endometrial adenocarcinomas divided into training (n = 43; cervical/endometrial adenocarcinomas = 11/32) and validation (n = 44; 14/30) datasets.Field Strength/SequenceThe 3T diffusion‐weighted (DW) MR imaging and MR spectroscopy.AssessmentMorphology, volumetric DW MR imaging and spectroscopy (MDS) scoring system with total points 0–5, based on presence of the following MR features assessed independently by two radiologists: (a) epicenter at the cervix, (b) rim enhancement, (c) disrupted cervical stromal integrity, (d) mean volumetric apparent diffusion coefficient values (ADCmean) higher than 0.98 × 10‐3 mm2/s, (e) fatty acyl δ 1.3 ppm more than 161.92 mM. Histopathology as gold standard.Statistical TestsLogistic regression and receiver operator characteristic (ROC) curves analysis.ResultsFor both the training and validation datasets, the MDS score achieved an accuracy of 93.0% and 84.1%, significantly higher than that of morphology (88.4% and 79.5%), ADC value (74.4% and 68.2%), and spectroscopy (81.4% and 68.2%; P < 0.05 for all). The performances of the scoring were superior to the morphology in the training dataset (areas under the receiver operating characteristics curve [AUC] = 0.95 vs. 0.89; P = 0.046), but not in the validation dataset (AUC = 0.90 vs. 0.85; P = 0.289).Data ConclusionMDS score has potentials to improve distinguishing adenocarcinomas of cervical or endometrial origin, and warrants large‐scale studies for further validation.Level of Evidence: 1Technical Efficacy: Stage 3J. Magn. Reson. Imaging 2018;47:1654–1666.
Need for recovery after emotional labor: Differential effects of daily deep and surface acting
Authors: Xanthopoulou Despoina , Bakker Arnold B. , Oerlemans Wido G.M. , Koszucka Maria 
Published: November 2017

SummaryThis diary study examines the psychological processes that contribute to daily recovery from emotional labor by combining emotion regulation with work‐home resources theories. We hypothesized that overall perceptions of display rules relate positively to daily deep and surface acting. Daily surface acting was expected to relate positively to exhaustion and negatively to flow during work and consequently, to a higher need for recovery at the end of the workday. In contrast, daily deep acting was hypothesized to relate positively to flow and negatively to exhaustion and consequently, to a lower need for recovery at the end of the workday. In turn, need for recovery was expected to associate negatively to vigor at bedtime through reduced relaxation during leisure. Fifty Dutch and Polish employees first filled in a survey, and then a diary for five consecutive workdays, twice per day: at the end of the workday and before sleep. Multilevel path analyses largely supported these hypotheses suggesting that surface acting has unfavorable implications, whereas deep acting has favorable implications for daily well‐being at work and recovery after work.