bluuebunny/crossref_metadata_2025_split huggingface dataset:
An investigation on the tribological behaviors of steel/copper and steel/steel friction pairs via lubrication with a graphene additive
Authors: Mao Junyuan , Chen Guangyan , Zhao Jun , He Yongyong , Luo Jianbin 
Published: January 2020

AbstractIn this study, the tribological behaviors of graphene as a lubricant additive for steel/copper and steel/steel friction pairs were compared. For the steel/copper friction pair, the graphene sheets remarkably decreased the coefficient of friction and wear scar depth under low loads, but these slightly increased under high loads. The steel/steel friction pair showed excellent tribological properties even under high loads. Severe plastic deformation on the copper surface reduced the stability of the graphene tribofilm because of a rough copper transfer film on the steel during the running-in period. The results provide a better understanding of the mechanism of graphene as a lubricant additive.
Spatially Bandgap-Graded MoS2(1−x)Se2x Homojunctions for Self-Powered Visible–Near-Infrared Phototransistors
Authors: Xu Hao , Zhu Juntong , Zou Guifu , Liu Wei , Li Xiao , Li Caihong , Ryu Gyeong Hee , Xu Wenshuo , Han Xiaoyu , Guo Zhengxiao , Warner Jamie H. , Wu Jiang , Liu Huiyun 
Published: January 2020

AbstractTernary transition metal dichalcogenide alloys with spatially graded bandgaps are an emerging class of two-dimensional materials with unique features, which opens up new potential for device applications. Here, visible–near-infrared and self-powered phototransistors based on spatially bandgap-graded MoS2(1−x)Se2x alloys, synthesized by a simple and controllable chemical solution deposition method, are reported. The graded bandgaps, arising from the spatial grading of Se composition and thickness within a single domain, are tuned from 1.83 to 1.73 eV, leading to the formation of a homojunction with a built-in electric field. Consequently, a strong and sensitive gate-modulated photovoltaic effect is demonstrated, enabling the homojunction phototransistors at zero bias to deliver a photoresponsivity of 311 mA W−1, a specific detectivity up to ~ 1011 Jones, and an on/off ratio up to ~ 104. Remarkably, when illuminated by the lights ranging from 405 to 808 nm, the biased devices yield a champion photoresponsivity of 191.5 A W−1, a specific detectivity up to ~ 1012 Jones, a photoconductive gain of 106–107, and a photoresponsive time in the order of ~ 50 ms. These results provide a simple and competitive solution to the bandgap engineering of two-dimensional materials for device applications without the need for p–n junctions.
Highly sensitive thin‐film capacitive sensor for online moisture measurement in transformer oil
Authors: Islam Tarikul , Tehseen Zeba , Kumar Lokesh 
Published: January 2020

This study describes a low‐cost sensor‐based scheme for online moisture measurement in transformer oil. Considering a harsh environment, moisture measurement of oil at ppm level is challenging, so the sensor should be highly sensitive and thermally and chemically stable. The conventional methods are mostly offline, have long test times and are costly. A thin‐film parallel plate capacitive moisture sensor has been fabricated using inexpensive materials to measure the moisture of fresh, aged and 0.5% water content oil samples. The moisture sensing film is highly hydrophilic and is made of alumina oxide, a very stable material. Experiments were conducted to determine the response parameters of the sensor in the presence of moist nitrogen gas, the concentration of which was measured by a commercial SHAW dew point meter. Experiments were also performed to measure the moisture of different oil samples in the laboratory. Results show that the output of the sensor is sensitive (6 pF/ppm moisture), has negligible hysteresis (∼1% at 1 kHz) and has fast response and recovery times (Tres = 70 s, Trec = 170 s).
Reduced Basis Greedy Selection Using Random Training Sets
Authors: Cohen Albert , Dahmen Wolfgang , DeVore Ronald , Nichols James 
Published: January 2020

Reduced bases have been introduced for the approximation of parametrized PDEs in applications where many online queries are required. Their numerical efficiency for such problems has been theoretically confirmed in Binev et al. (SIAM J. Math. Anal. 43 (2011) 1457–1472) and DeVore et al. (Constructive Approximation 37 (2013) 455–466), where it is shown that the reduced basis space Vn of dimension n, constructed by a certain greedy strategy, has approximation error similar to that of the optimal space associated to the Kolmogorov n-width of the solution manifold. The greedy construction of the reduced basis space is performed in an offline stage which requires at each step a maximization of the current error over the parameter space. For the purpose of numerical computation, this maximization is performed over a finite training set obtained through a discretization of the parameter domain. To guarantee a final approximation error ε for the space generated by the greedy algorithm requires in principle that the snapshots associated to this training set constitute an approximation net for the solution manifold with accuracy of order ε. Hence, the size of the training set is the ε covering number for M and this covering number typically behaves like exp(Cε−1/s) for some C > 0 when the solution manifold has n-width decay O(n−s). Thus, the shear size of the training set prohibits implementation of the algorithm when ε is small. The main result of this paper shows that, if one is willing to accept results which hold with high probability, rather than with certainty, then for a large class of relevant problems one may replace the fine discretization by a random training set of size polynomial in ε−1. Our proof of this fact is established by using inverse inequalities for polynomials in high dimensions.
Effect of SiO2 Nanoparticles Addition on the Flexural Strength of Repaired Acrylic Denture Base
Authors: Gad Mohammed Moustafa Ahmed , Abualsaud Reem , Al-Thobity Ahmad M. , Almaskin Danah F. , AlZaher Zahra A. , Abushowmi Tahani H. , Qaw Masoumah S. , Akhtar Sultan , Al-Harbi Fahad A. 
Published: January 2020

Abstract
Objective The objective of this study was to evaluate the effect of nano-SiO2 addition on the flexural strength (FS) of repaired acrylic denture base.
Materials and Methods Heat-polymerized acrylic resin specimens were fabricated in dimensions of (65 × 10 × 2.5 ± 0.1 mm3 ) and then sectioned and prepared, creating repair gap with butt (90 degrees) and bevel (45 degrees) repair surface designs forming two main groups according to joint design. Further subdivision was done into four groups (n = 10) according to nano-SiO2 concentration: one unmodified group and three modified groups (0.25, 0.5, and 0.75 wt %) in the autopolymerized repair resin. Each pair of a specimen was assembled in a mold and repaired according to manufacturer’s recommendations.
Statistical Analysis Three-point bending test was done to measure FS, followed by scanning electron microscope (SEM) examination for fracture surface analysis. Data were analyzed using ANOVA and Tukey’s post hoc test (α = 0.05).
Results The addition of nano-SiO2 significantly improved FS of repaired acrylic resin in comparison to the unmodified group (p ˂ 0.05). For butt joint, significant differences between nano-SiO2 reinforced groups were noticed (p ˂ 0.05), while reinforced beveled groups did not differ significantly (p ˃ 0.05). Bevel design remarkably increased FS compared with butt design per respective filler concentration. From the SEM images, improved FS was presented with a homogeneous distribution of nano-SiO2 within polymethyl methacrylate.
Conclusion Nano-SiO2 addition to repair resin and 45 degree-beveled repair surface increased FS of repaired acrylic resin.
M06-SX screened-exchange density functional for chemistry and solid-state physics
Authors: Wang Ying , Verma Pragya , Zhang Lujia , Li Yaqi , Liu Zhonghua , Truhlar Donald G. , He Xiao 
Published: January 2020

Significance
Density functionals with Hartree–Fock exchange have been widely used for a wide range of chemical applications, but the nonlocal character of exchange makes long-range exchange computationally expensive for solid-state calculations with periodic boundary conditions, and full exchange is nonphysical for condensed-phase systems. Here, we present a screened-exchange (SX) density functional, M06-SX, that is especially designed to have good accuracy for both solid-state physics and chemical applications with less computational cost than full Hartree–Fock exchange. The M06-SX functional gives accuracy comparable to functionals with full Hartree–Fock exchange for predicting chemical properties of molecules, while also being practical with good accuracy for plane wave calculations on band gaps and lattice constants of solids.
Scd1 controls de novo beige fat biogenesis through succinate-dependent regulation of mitochondrial complex II
Authors: Liu Keli , Lin Liangyu , Li Qing , Xue Yueqing , Zheng Fanjun , Wang Guan , Zheng Chunxing , Du Liming , Hu Mingyuan , Huang Yin , Shao Changshun , Kong Xiangyin , Melino Gerry , Shi Yufang , Wang Ying 
Published: January 2020

Significance
Adipose tissue-derived mesenchymal stem cells (ADSCs) are well-known in the generation of both white and beige adipocytes and the maintenance of adipose tissue homeostasis. Stearoyl-coenzyme A desaturase 1 (Scd1) is a rate-limiting enzyme for monounsaturated fatty acids. Here, we show that deficiency of Scd1 promotes the formation of beige adipocytes in white adipose tissue by directing de novo beige adipogenesis. In the absence of Scd1, succinate accumulation was enhanced in ADSCs and fueled mitochondrial complex II activities. Notably, we demonstrate that succinate controls the potential of beige adipogenesis of ADSCs both in vitro and in vivo. These findings reveal an unidentified negative regulatory relationship between Scd1 and succinate during adipogenesis, holding great potential for combating obesity.
A strategy for designing allosteric modulators of transcription factor dimerization
Authors: Oasa Sho , Vukojević Vladana , Rigler Rudolf , Tsigelny Igor F. , Changeux Jean-Pierre , Terenius Lars 
Published: January 2020

Significance
Transcription factors in the bHLH family are potentially relevant for tumor growth. Activation requires homodimerization or heterodimerization. Thus, the dimerization step is a likely significant drug target. The oligodendrocyte transcription factor 2 (OLIG2) is overexpressed in gliomas. Here, we developed a fluorescence cross-correlation spectroscopy protocol to examine 10 compounds selected using a pharmacophore-based computational strategy targeting OLIG2 dimerization. We showed that the potency to interact with OLIG2 dimerization in live cells correlates with carcinostatic efficacy. The data indicate a promising approach toward drug development targeting transcription factor overactivity and protein–protein interaction more generally.
Variability of running coordination in experts and novices: A 3D uncontrolled manifold analysis
Authors: Möhler Felix , Marahrens Sonja , Ringhof Steffen , Mikut Ralf , Stein Thorsten 
Published: January 2020

ABSTRACTThe uncontrolled manifold (UCM) approach has been widely used in recent studies to examine variability in daily tasks; however, it has not yet been used to study running or the effects of expertise. Therefore, the aim of this study was to analyse the synergy structure stabilizing the centre of mass (CoM) trajectory in experts compared to novices during running at two different speeds using a subject‐specific 3D model. A total of 25 healthy young adults (13 experts, 12 novices) participated in the study. All subjects ran at 10 and 15 km h−1 on a treadmill. In each case, kinematics of 20 consecutive gait cycles were recorded and the effects of expertise and gait cycle phase on the synergy structure were investigated at both speeds. Specifically, the variance affecting the CoM , the variance not affecting the CoM , and their ratio were analysed. Descriptively, in both groups there was a synergy stabilizing the CoM trajectory in running. However, the ANOVA showed no differences in between the two groups. In novices, and were significantly higher compared to experts at the 15 km h−1 condition. In both groups, there was more variability in the stance phase compared to the flight phase in the majority of cases. The results indicate that experts adopted a more consistent running style. The stride‐to‐stride variability was diminished but not abolished. This difference was only visible at the 15 km h−1 condition. Furthermore, variability was less constrained in the stance phase compared to the flight phase.
Effects of vitamin D3 supplementation for 12 weeks on serum levels of anabolic hormones, anaerobic power, and aerobic performance in active male subjects: A randomized, double‐blind, placebo‐controlled trial
Authors: Ramezani Ahmadi Amirhossein , Mohammadshahi Majid , Alizadeh Aliakbar , Ahmadi Angali Kambiz , Jahanshahi Alireza 
Published: January 2020

AbstractMaintenance of the serum 25‐hydroxyvitamin D (25‐OH‐D) concentration at recommended levels is essential due to its role in the regulation of anabolic hormones and athletic performance. However, the results of the clinical experiments in athletes are controversial. The present study aimed to investigate the effect of vitamin D3 supplement on serum levels of anabolic hormones, cortisol, anaerobic and aerobic performance in active males. In this double‐blind, randomized controlled trial, 46 active males randomly assigned to vitamin D3 supplement (VDS; 2000 IU/day) or placebo for 12 weeks. The Wingate test, VO2max, and serum levels of 25‐OH‐D, Parathyroid hormone (PTH), total testosterone, growth hormone (GH), Insulin‐like growth factor‐1 (IGF‐1), and cortisol were assessed. Subjects in the VDS group had a higher serum level of 25‐OH‐D (p = 0.004), VO2max (p = 0.016), and average power (p = 0.044) compared to the placebo at the end of the study. Also, lower levels of PTH (p = 0.004) and fatigue index (p < 0.001) were observed in VDS group at the end of the study. The serum cortisol levels were reduced significantly only in subjects with vitamin D deficiency in VDS group (p = 0.042). There was a significant reduction in serum testosterone levels in VDS group (p = 0.013). No change was indicated in serum levels of GH and IGF‐1 in VDS group compared to the placebo (p > 0.05). The present study showed an improvement in aerobic capacity, anaerobic performance, and vitamin D status following vitamin D3 supplementation. However, more studies are required for the effect of vitamin D3 on serum concentration of anabolic hormones.
Joint reconstruction of multiple gene networks by simultaneously capturing inter-tumor and intra-tumor heterogeneity
Authors: Tu Jia-Juan , Ou-Yang Le , Yan Hong , Zhang Xiao-Fei , Qin Hong 
Published: January 2020

AbstractMotivationReconstruction of cancer gene networks from gene expression data is important for understanding the mechanisms underlying human cancer. Due to heterogeneity, the tumor tissue samples for a single cancer type can be divided into multiple distinct subtypes (inter-tumor heterogeneity) and are composed of non-cancerous and cancerous cells (intra-tumor heterogeneity). If tumor heterogeneity is ignored when inferring gene networks, the edges specific to individual cancer subtypes and cell types cannot be characterized. However, most existing network reconstruction methods do not simultaneously take inter-tumor and intra-tumor heterogeneity into account.ResultsIn this article, we propose a new Gaussian graphical model-based method for jointly estimating multiple cancer gene networks by simultaneously capturing inter-tumor and intra-tumor heterogeneity. Given gene expression data of heterogeneous samples for different cancer subtypes, a non-cancerous network shared across different cancer subtypes and multiple subtype-specific cancerous networks are estimated jointly. Tumor heterogeneity can be revealed by the difference in the estimated networks. The performance of our method is first evaluated using simulated data, and the results indicate that our method outperforms other state-of-the-art methods. We also apply our method to The Cancer Genome Atlas breast cancer data to reconstruct non-cancerous and subtype-specific cancerous gene networks. Hub nodes in the networks estimated by our method perform important biological functions associated with breast cancer development and subtype classification.Availability and implementationThe source code is available at https://github.com/Zhangxf-ccnu/NETI2.Supplementary informationSupplementary data are available at Bioinformatics online.
CytoSeg 2.0: automated extraction of actin filaments
Authors: Nowak Jacqueline , Gennermann Kristin , Persson Staffan , Nikoloski Zoran 
Published: January 2020

Abstract

Motivation
Actin filaments (AFs) are dynamic structures that substantially change their organization over time. The dynamic behavior and the relatively low signal-to-noise ratio during live-cell imaging have rendered the quantification of the actin organization a difficult task.

Results
We developed an automated image-based framework that extracts AFs from fluorescence microscopy images and represents them as networks, which are automatically analyzed to identify and compare biologically relevant features. Although the source code is freely available, we have now implemented the framework into a graphical user interface that can be installed as a Fiji plugin, thus enabling easy access by the research community.

Availability and implementation
CytoSeg 2.0 is open-source software under the GPL and is available on Github: https://github.com/jnowak90/CytoSeg2.0.

Supplementary information
Supplementary data are available at Bioinformatics online.
Human Anterior Insula Encodes Performance Feedback and Relays Prediction Error to the Medial Prefrontal Cortex
Authors: Billeke Pablo , Ossandon Tomas , Perrone-Bertolotti Marcela , Kahane Philippe , Bastin Julien , Jerbi Karim , Lachaux Jean-Philippe , Fuentealba Pablo 
Published: January 2020

AbstractAdaptive behavior requires the comparison of outcome predictions with actual outcomes (e.g., performance feedback). This process of performance monitoring is computed by a distributed brain network comprising the medial prefrontal cortex (mPFC) and the anterior insular cortex (AIC). Despite being consistently co-activated during different tasks, the precise neuronal computations of each region and their interactions remain elusive. In order to assess the neural mechanism by which the AIC processes performance feedback, we recorded AIC electrophysiological activity in humans. We found that the AIC beta oscillations amplitude is modulated by the probability of performance feedback valence (positive or negative) given the context (task and condition difficulty). Furthermore, the valence of feedback was encoded by delta waves phase-modulating the power of beta oscillations. Finally, connectivity and causal analysis showed that beta oscillations relay feedback information signals to the mPFC. These results reveal that structured oscillatory activity in the anterior insula encodes performance feedback information, thus coordinating brain circuits related to reward-based learning.
Enriching Topic Coherence on Reviews for Cross-Domain Recommendation
Authors: Saraswat Mala , Chakraverty Shampa 
Published: January 2020

Abstract
With the advent of e-commerce sites and social media, users express their preferences and tastes freely through user-generated content such as reviews and comments. In order to promote cross-selling, e-commerce sites such as eBay and Amazon regularly use such inputs from multiple domains and suggest items with which users may be interested. In this paper, we propose a topic coherence-based cross-domain recommender model. The core concept is to use topic modeling to extract topics from user-generated content such as reviews and combine them with reliable semantic coherence techniques to link different domains, using Wikipedia as a reference corpus. We experiment with different topic coherence methods such as pointwise mutual information (PMI) and explicit semantic analysis (ESA). Experimental results presented demonstrate that our approach, using PMI as topic coherence, yields 22.6% and using ESA yields 54.4% higher precision as compared with cross-domain recommender system based on semantic clustering.
Raging elephants: effects of human disturbance on physiological stress and reproductive potential in wild Asian elephants
Authors: Tang Ruchun , Li Wenwen , Zhu Di , Shang Xiaotong , Guo Xianming , Zhang Li 
Published: January 2020

AbstractHuman disturbance has become a widespread threat to wildlife viability. The Asian elephant (Elephas maximus), an endangered and disturbance-prone species, is under severe threat from habitat loss and fragmentation, human–elephant conflict and poaching. Establishing connections between human disturbance, stress responses and reproduction is crucial for assessing the long-term survivability of a species and will provide critical information for conservation management. The current study investigated the effects of human disturbance on population-level stress responses and stress-related effects on reproductive potential of wild Asian elephants in Xishuangbanna Dai Autonomous Prefecture, China. We used a radioimmunoassay to measure the concentration of fecal cortisol and estradiol in 257 samples collected from five local populations at 15 sites over 4 years. Human disturbance in Xishuangbanna was quantified based on the Ecological-Niche Factor Analysis model. We found that fecal cortisol concentrations were strongly positively correlated with the degree of human disturbance and increased markedly with the expansion of tea plantations. Percentage of non-stressed individuals in a population was higher depending on the extend of undisturbed area in their home ranges. Fecal estradiol concentrations decreased significantly with increasing stress levels. Our results suggest that human disturbance poses environmental challenges to wild Asian elephant populations, and chronic exposure to human disturbance could lead to population decline. The study demonstrates the efficacy of non-invasive endocrine monitoring for further informing management decisions and developing conservation strategies.
MitraClip® as bridging strategy for heart transplantation in Chagas cardiomyopathy: a case report
Authors: Vasquez-Rodríguez Juan Felipe , Medina Héctor Manuel , Cabrales Jaime Ramón , Torres Adriana Gisella 
Published: January 2020

AbstractBackgroundPatients with end-stage heart failure, suffering from severe pulmonary hypertension (PH) and elevated pulmonary vascular resistance, are not eligible for heart transplant due to high mortality risk and primary graft dysfunction. Severe PH may be favoured by functional severe mitral regurgitation, which is present in many cardiopathies like end-stage Chagasic cardiomyopathy.Case summaryWe present a case of a young man with end-stage heart failure secondary to Chagas cardiomyopathy with severe functional mitral regurgitation (FMR) and severe PH. The patient received percutaneous correction with MitraClip® system reducing PH and making him a suitable candidate for heart transplant.DiscussionIn patients with advanced heart failure, FMR, and severe PH, optimal treatment according to current guide lines is recommended. MitraClip® therapy appears to be safe and effective for control of severe PH as a bridge measure for cardiac transplantation.