期刊文献+
共找到778,682篇文章
< 1 2 250 >
每页显示 20 50 100
Structural Study, Vibrational, Optical, Thermal Properties and Hirshfeld Surface Analysis of a New Iron (III) Complex: FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) 认领
1
作者 Amal Arouri Rihab Dridi +1 位作者 Riadh Kefi Mohamed Faouzi Zid 《晶体结构理论与应用(英文)》 2021年第1期14-26,共13页
The title compound, FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) consists of tw... The title compound, FeCl<sub>4</sub>(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>) consists of two [(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>) (C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>)]<sup>+</sup> organic cations and [FeCl<sub>4</sub>]<sup>-</sup> anion. The geometry of the iron ion is tetrahedral, formed by four chlorine atoms. The complex was characterized by single crystal X-ray diffraction, Fourier Transform Infrared spectroscopy, thermal analysis and UV-Visible spectroscopy. Hirshfeld surface analysis was also used for understanding the intermolecular interactions in the crystal packing. Single-crystal X-ray diffraction analysis indicates that this complex crystallizes in the monoclinic system, P2<sub>1</sub>/c space group with a = 7.598 (3) &#197;, b = 13.694 (4) &#197;, c = 17.105 (5) &#197;, <i>β</i><i> </i>= 97.203 (6)° V = 1765.7 (10) &#197;<sup>3</sup> and Z = 4. The [FeCl<sub>4</sub>]<sup>-</sup> anion and [(C<sub>5</sub>N<sub>2</sub>H<sub>6</sub>)(C<sub>5</sub>N<sub>2</sub>H<sub>5</sub>)]<sup>+</sup> cations are linked through three-dimensional hydrogen-bonding network consisting of N-H...Cl and π-π interactions. Hirshfeld surface analysis and the related 2D fingerprint plots reveal that the complex is dominated by N-H...Cl contacts. 展开更多
关键词 COMPLEX Crystal Structure X-Ray Analysis Optical Study Thermal Analysis Hirshfeld Surface
在线阅读 免费下载
Water Quality Assessment in the Bamoun Plateau, Western-Cameroon: Hydrogeochemical Modelling and Multivariate Statistical Analysis Approach 认领
2
作者 Zakari Mfonka Amidou Kpoumié +7 位作者 Abdou Nasser Ngouh Oumar Farouk Mouncherou Daouda Nsangou Felaniaina Rakotondrabe Alain Fouépé Takounjou Mounira Zammouri Jules Rémy Ndam Ngoupayou Paul-Désiré Ndjigui 《水资源与保护(英文)》 2021年第2期112-138,共27页
This study focuses on the geochemical and bacteriological investigation of surface and ground water in the Bamoun plateau (Western-Cameroon). During the period from September 2013 to August 2014, 71 samples were colle... This study focuses on the geochemical and bacteriological investigation of surface and ground water in the Bamoun plateau (Western-Cameroon). During the period from September 2013 to August 2014, 71 samples were collected from two springs, one borehole, four wells and the Nchi stream for analysis of major elements. In order to obtain the characteristics of the various species of bacteria, 7 samples were selected. The analytical method adopted for this study is the conventional hydrochemical technic and multivariate statistical analysis, coupled with the hydrogeochemical modelling. The results revealed that, water from the zone under study are acidic to basic, very weakly to weakly mineralized. Four types of water were identified: 1) CaMg-HCO<sub>3</sub>;2) CaMg-Cl-SO<sub>4</sub>;3) NaCl-SO<sub>4</sub> and 4) NaK-HCO<sub>3</sub>. The major elements were all listed in the World Health Organization guidelines for drinking water quality, except for nitrates which was found at a concentration > 50 mg /l <span style="white-space:nowrap;">NO<sup>-</sup><sub style="margin-left:-7px;">3</sub> </span>in the borehole F401. As for the hydrobiological aspect, the entire sample contained all the bacteriological species except for spring S301 and well P401. According to the hydrogeochemical modelling, the Gibbs model and multivariate statistical tests, the quality of surface and ground water of the Foumban locality is influenced by two important factors: 1) the natural factors characterized by the water-rock interaction, evapotranspiration/crystallization, 2) the anthropogenic factors such as: uncontrolled discharges of liquid and solid effluents of all kinds and without any prior treatment within the ground and the strong urbanization accompanied by lack of sanitation and insufficient care. 展开更多
关键词 Foumban Surface and Ground Water Water-Rock Interaction Bacteriological Parameters Hierarchical Clustering Analysis Principal Component Analysis
在线阅读 免费下载
Effect of Antimicrobial Edible Films on the Sensory and Physical Properties of Organic Spinach in Salad Bags 认领
3
作者 Kamini Joshi Patricia Sparks +3 位作者 Mendel Friedman Carl Olsen Tara McHugh Sadhana Ravishankar 《食品与营养科学(英文)》 2021年第2期176-193,共18页
The effects of antimicrobial edible films containing carvacrol and cinnamaldehyde on organic baby spinach were determined via sensory analysis and changes in physical properties. Edible films made from pulp of hibiscu... The effects of antimicrobial edible films containing carvacrol and cinnamaldehyde on organic baby spinach were determined via sensory analysis and changes in physical properties. Edible films made from pulp of hibiscus, apple, or carrot containing carvacrol or cinnamaldehyde at 0.5%, 1.5%, or 3% concentrations were added to organic baby spinach in plastic bags. These bags were stored at 4<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#ffffff;"="">°</span>C for 20-24h before performing sensory evaluation and measuring changes in physical properties. A randomized block design with an affective test was used. Preference liking was evaluated based on a 9-point hedonic scale for aroma, color, freshness, mouthfeel, flavor, and overall acceptability. Additionally, panelists quantified each sample using a 5-point hedonic scale for pungency, browning, bitterness, off-odor, and sourness. The color and texture of spinach samples were measured. Edible films containing cinnamaldehyde had the highest preference liking based on aroma, color, freshness, mouthfeel, flavor, and overall acceptability than those containing carvacrol and were the most likely to be purchased by panelists;therefore, cinnamaldehyde can potentially be used as an alternative sanitization option. There were no significant (p ≤ 0.05) changes in firmness or color values between spinach treated with antimicrobial films and controls. The results provide the produce industry with options for incorporating antimicrobial films into salad bags without influencing the physical or sensory properties of baby spinach. 展开更多
关键词 Edible Films Plant Antimicrobials Sensory Analysis Organic Baby Spinach Texture Analysis Color Measurements
在线阅读 免费下载
Research trends, hot spots and prospects for necroptosis in the field of neuroscience 认领
4
作者 Wei-Tao Yan Shuang Lu +5 位作者 Yan-Di Yang Wen-Ya Ning Yan Cai Xi-Min Hu Qi Zhang Kun Xiong 《中国神经再生研究:英文版》 SCIE CAS 2021年第8期1628-1637,共10页
There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by env... There are two types of cell death-apoptosis and necrosis. Apoptosis is cell death regulated by cell signaling pathways, while necrosis has until recently been considered a passive mechanism of cell death caused by environmental pressures. However, recent studies show that necrosis can also be regulated by specific cell signaling pathways. This mode of death, termed necroptosis, has been found to be related to the occurrence and development of many diseases. We used bibliometrics to analyze the global output of literature on necroptosis in the field of neuroscience published in the period 2007–2019 to identify research hotspots and prospects. We included 145 necroptosisrelated publications and 2239 references published in the Web of Science during 2007–2019. Visualization analysis revealed that the number of publications related to necroptosis has increased year by year, reaching a peak in 2019. China is the country with the largest number of publications. Key word and literature analyses demonstrated that mitochondrial function change, stroke, ischemia/reperfusion and neuroinflammation are likely the research hotspots and future directions of necroptosis research in the nervous system. The relationship between immune response-related factors, damage-associated molecular patterns, pathogen-associated molecular patterns and necroptosis may become a potential research hotspot in the future. Taken together, our findings suggest that although the inherent limitations of bibliometrics may affect the accuracy of the literature-based prediction of research hotspots, the results obtained from the included publications can provide a reference for the study of necroptosis in the field of neuroscience. 展开更多
关键词 bibliometric analysis CITATIONS CiteSpace H-INDEX NECROPTOSIS network analysis NEUROSCIENCE output VOSviewer Web of Science
在线阅读 下载PDF
Flow Characteristics of Two-Dimensional Supersonic Under-Expanded Coanda-Reattached Jet 认领
5
作者 Tetsuji Ohmura Toshihiko Shakouchi +1 位作者 Shunsuke Fukushima Koichi Tsujimoto 《流量控制、测量及可视化(英文)》 2021年第1期1-14,共14页
<span><span style="font-family:;" "=""><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">When there is a wall near ... <span><span style="font-family:;" "=""><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">When there is a wall near the jet, it deflects and flows while being attached to the wall owing to the Coanda effect. The flow characteristics of the incompressible and two-imensional (2D) Coanda-reattached jets have been considerably explained. However, 2D supersonic under-expanded jets, reattached to side walls, have not been sufficiently investigated. These jets are used in gas-atomization to produce fine metal powder particles of several micrometers to several tens micrometers. In this case, the supersonic under-expanded jets are issued from an annular nozzle, which is set around a vertically in</span><span style="font-family:Verdana;">stalled circular nozzle for molten metal. The jet flow at the center</span><span style="font-family:Verdana;"> cross</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">-</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">section of the annular jet resembles a 2D Coanda-reattached jet that deflects and attaches on the central axis. In this study, the flow characteristics of a supersonic under-expanded Coanda air jet from a 2D nozzle that reattaches to an offset side wall are elucidated through experiment and numerical analysis. For numerical analysis, we show how much it can express experimental results. The effects of supply pressure </span><i><span style="font-family:Verdana;">P</span><span style="font-family:Verdana;"><sub></sub></span><span style="font-family:Verdana;"></span></i><sub><span style="font-family:Verdana;">0</span><span style="font-family:Verdana;"></span></sub></span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> on the flow characteristics such as the flow pattern, size of shock cell, reattachment distance, and velocity and pressure distributions, etc. are examined. The flow pattern was visualiz 展开更多
关键词 Supersonic Flow Under-Expanded Jet Coanda Reattached Jet Flow Visualization Gas-Atomization Experimental Analysis Numerical Analysis
在线阅读 免费下载
Determination of Optimum Slope Design for Northern Boxcut in Zone 5 Khoemacau Copper Mine, Botswana 认领
6
作者 Maipelo Gaopatwe Tefo Kgopana +1 位作者 Bame Molebatsi Rahul Verma 《地质学期刊(英文)》 2021年第2期38-48,共11页
An optimum design of box cuts in soil formations is very crucial in order to obviate the major risk factors originating from the collapse of sidewalls and flooding of excavations during storm rainfall. The present pap... An optimum design of box cuts in soil formations is very crucial in order to obviate the major risk factors originating from the collapse of sidewalls and flooding of excavations during storm rainfall. The present paper aims to present a holistic classification of the Kalahari Formation stratigraphy in Zone 5 and define engineering properties of each lithological unit, in order to establish a safe working design. For the present objectives, collection of data was carried out through logging core from selected geotechnical boreholes drilled within vicinity of the proposed Northern mine box cut. Hydrogeological assessments and feasibility studies within the purview of study region were also considered. Geotechnical logging parameters gathered on site were derived from the Rock Mass Rating system (RMR) for design requirements [<a href="#ref1">1</a>]. Input parameters and material characteristics taken from laboratory test results provided by KCM were incorporated in the analysis. The box cut slopes were modelled in “Rocscience software” for evaluation of safety factor using “limit equilibrium method”. Slope optimization required the slope surface to be as steep as possible while maintaining an adequate factor of safety ranging from 1.5 - 1.8. For the box cut design with optimum safety, the recommended parameters are: stable slope angle—35<span style="white-space:nowrap;">&#176;</span> - 40<span style="white-space:nowrap;">&#176;</span>;ramp angle—8<span style="white-space:nowrap;">&#176;</span>, depth of pit—60 meters;bench width—4.9 meters and the bench length—13.25 meters. 展开更多
关键词 Boxcut Slope Slope Stability Finite Element Analysis Limit Equilibrium Analysis Rocscience Software
在线阅读 免费下载
Spectrochemical Analysis of Bottled and Tap Water from Selected Counties of Middle Tennessee, USA 认领
7
作者 Aminul Islam Chowdhury Ravneet Kaur +2 位作者 Anonya Akuley-Amenyenu Abua Ikem Sam O. Dennis 《水资源与保护(英文)》 2021年第1期20-31,共12页
A total of 37 elements were determined in tap and bottled water samples from six counties of Middle Tennessee (USA) by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The overarching goal of the st... A total of 37 elements were determined in tap and bottled water samples from six counties of Middle Tennessee (USA) by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The overarching goal of the study is to dispel the myth that bottled water is better than tap water or vice versa. Other parameters analyzed were pH, conductivity, and Total Dissolved Solids (TDS). The results were compared with the Maximum Contaminant Limit (MCL) reported by the US Environmental Protection Agency (US-EPA). The concentrations of phosphorus, silicon, fluoride, and chloride conformed to the established values by US-EPA maximum contaminant level corresponding value. The level of Aluminum (Al), Boron (B), Chromium (Cr), Cobalt (Co), Copper (Cu), Iron (Fe), Lithium (Li), Manganese (Mn), Nickel (Ni), Titanium (Ti), Vanadium (V), and Zinc (Zn) conformed to the established values by governmental agencies (USEPA). Heavy metals such as Arsenic (As), Cadmium (Cd), Cobalt (Co), Lead (Pb), Mercury (Hg), and Silver (Ag) were detected in the tap water of the urban (Davidson) and urbanizing (Rutherford and Williamson) counties;suggesting that rural counties had a less heavy metal concentration in their drinking water sources than urban counties (P < 0.05). However, the values were below the Maximum Contaminant Levels (MCLs). 展开更多
关键词 Heavy Metals FLUORIDE ICP-OES Maximum Contaminant Level (MCL) Principal Component Analysis (PCA) Cluster Analysis
在线阅读 免费下载
An integrative multivariate approach for predicting functional recovery using magnetic resonance imaging parameters in a translational pig ischemic stroke model 认领
8
作者 Erin E.Kaiser J.C.Poythress +6 位作者 Kelly M.Scheulin Brian J.Jurgielewicz Nicole A.Lazar Cheolwoo Park Steven L.Stice Jeongyoun Ahn Franklin D.West 《中国神经再生研究:英文版》 SCIE CAS 2021年第5期842-850,共9页
Magnetic resonance imaging(MRI)is a clinically relevant,real-time imaging modality that is frequently utilized to assess stroke type and severity.However,specific MRI biomarkers that can be used to predict long-term f... Magnetic resonance imaging(MRI)is a clinically relevant,real-time imaging modality that is frequently utilized to assess stroke type and severity.However,specific MRI biomarkers that can be used to predict long-term functional recovery are still a critical need.Consequently,the present study sought to examine the prognostic value of commonly utilized MRI parameters to predict functional outcomes in a porcine model of ischemic stroke.Stroke was induced via permanent middle cerebral artery occlusion.At 24 hours post-stroke,MRI analysis revealed focal ischemic lesions,decreased diffusivity,hemispheric swelling,and white matter degradation.Functional deficits including behavioral abnormalities in open field and novel object exploration as well as spatiotemporal gait impairments were observed at 4 weeks post-stroke.Gaussian graphical models identified specific MRI outputs and functional recovery variables,including white matter integrity and gait performance,that exhibited strong conditional dependencies.Canonical correlation analysis revealed a prognostic relationship between lesion volume and white matter integrity and novel object exploration and gait performance.Consequently,these analyses may also have the potential of predicting patient recovery at chronic time points as pigs and humans share many anatomical similarities(e.g.,white matter composition)that have proven to be critical in ischemic stroke pathophysiology.The study was approved by the University of Georgia(UGA)Institutional Animal Care and Use Committee(IACUC;Protocol Number:A2014-07-021-Y3-A11 and 2018-01-029-Y1-A5)on November 22,2017. 展开更多
关键词 behavior testing canonical correlation analysis gait analysis Gaussian graphical models ischemic stroke magnetic resonance imaging pig model principal component analysis
在线阅读 下载PDF
Bibliometric analysis of researches of Orem self-care model in China based on BICOMB 认领
9
作者 Miao Li Yue Cheng 《TMR整合护理》 2021年第1期21-29,共9页
Objective:To analyze the hotspots of the Orem self-care model research from the construction of CNKI database to May 2019,and to understand the research status in this field and to explore its development trend.Method... Objective:To analyze the hotspots of the Orem self-care model research from the construction of CNKI database to May 2019,and to understand the research status in this field and to explore its development trend.Methods:"Orem self-care model"was used as the search term to search CNKI database,and the Bibliographic Items Co-occurrence Matrix Builder(BICOMB)was used to perform bibliometric analysis on the annual distribution,authors,keywords,etc.in related articles,and SPSS 23.0 was utilized to cluster analysis of high-frequency keywords.Results:A total of 1845 associated articles were included.The annual change of Orem self-care model literatures showed an increasing trend and a total of 1604 first authors were extracted.Today Nurse published the most relevant literatures.The research extracted 56 high-frequency keywords,accounting for 50.88%of the total frequency.Co-word cluster analysis obtained five research hotspots:clinical application effect and patient satisfaction of Orem self-care model;self-care ability and quality of life of breast cancer patients;self-care behaviors for the elderly and community care;rehabilitation nursing of stroke and spinal cord injury;Orem self-care model,nursing theory.Conclusion:Analyzing the research hotspots of Orem self-care model in recent years is helpful to understand the current status in this field and future development trends,and provide references for future nursing clinical practice work and education and scientific research. 展开更多
关键词 Orem self-care model Co-occurrence analysis system Research hotspot Bibliometric analysis
在线阅读 下载PDF
Homotopy Analysis Method for a Conservative Nonlinear Oscillator with Fractional Power 认领
10
作者 Huaxiong Chen Yanyan Wang 《应用数学与应用物理(英文)》 2021年第1期31-40,共10页
In this paper, the homotopy analysis method is applied to deduce the periodic solutions of a conservative nonlinear oscillator for which the elastic force term is proportional to<em> u</em><sup>1/3&l... In this paper, the homotopy analysis method is applied to deduce the periodic solutions of a conservative nonlinear oscillator for which the elastic force term is proportional to<em> u</em><sup>1/3</sup>. By introducing the auxiliary linear operator and the initial guess of solution, the homotopy analysis solving is set up. By choosing the suitable convergence-control parameter, the accurate high-order approximations of solution and frequency for the whole range of initial amplitudes can easily be obtained. Comparison of the results obtained using this method with those obtained by different methods reveals that the former is more accurate, effective and convenient for these types of nonlinear oscillators. 展开更多
关键词 Homotopy Analysis Method Approximate Solutions Fractional Power Nonlinear Oscillation
在线阅读 免费下载
Thermal Effect of a Revolving Gaussian Beam on Activating Heat-Sensitive Nociceptors in Skin 认领
11
作者 Hongyun Wang Wesley A. Burgei Hong Zhou 《应用数学与应用物理(英文)》 2021年第1期88-100,共13页
We consider the problem of inducing withdrawal reflex on a test subject by exposing the subject’s skin to an electromagnetic beam. Heat-sensitive nociceptors in the skin are activated wherever the temperature is abov... We consider the problem of inducing withdrawal reflex on a test subject by exposing the subject’s skin to an electromagnetic beam. Heat-sensitive nociceptors in the skin are activated wherever the temperature is above the activation temperature. Withdrawal reflex occurs when the activated volume reaches a threshold. Previously we studied static beams with 3 types of power density distribution: Gaussian, super-Gaussian, and flat-top. We found that the flaptop is the best and the Gaussian is the worst in their performance with regard to 1) minimizing the time to withdrawal reflex, 2) minimizing the energy consumption and 3) minimizing the maximum temperature increase. The less-than-desirable performance of Gaussian beams is attributed to the uneven distribution of power density resulting in low energy efficiency: near the beam center the high power density does not contribute proportionally to increasing the activated volume;outside the beam effective radius the low power density fails to activate nociceptors. To overcome the drawbacks of Gaussian beams, in this study, we revolve a Gaussian beam around a fixed point to make the power density more uniformly distributed. We optimize the performance over two parameters: the spot size of static beam and the radius of beam revolution. We find that in comparison with a static Gaussian beam, a revolving Gaussian beam can reduce the energy consumption, and at the same time lower the maximum temperature. 展开更多
关键词 Heat-Sensitive Nociceptor Heat-Induced Withdrawal Reflex Revolving Gaussian Beam Optimizing Energy Consumption Non-Dimensional Analysis
在线阅读 免费下载
Taxonomic Studies on Some Members of the Genus <i>Abutilon</i>Mill. (Malvaceae) 认领
12
作者 Dhafer A. Alzahrani Enas J. Albokhari Abrar Khoj 《美国植物学期刊(英文)》 2021年第2期199-220,共22页
The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using diffe... The relationship between six </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species was examined using different taxonomic investigation tools. The investigation was carried out using morphological and numerical studies. Fresh materials of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> species were collected from different localities in Saudi Arabia during 2018 and 2019. Numerical analysis was based on the Principle Coordinates, the Principle Component and the Unweighted Pair Group Method with Arithmetic Algorithm Clustering. The results indicated that there were significant differences based on the morphological characters especially in the leaves, fruits and flowers features. Morphometric studies revealed that the six species of </span><i><span style="font-family:Verdana;">Abutilon</span></i><span style="font-family:Verdana;"> clearly separated in all different analysis. 展开更多
关键词 Taxonomy MALVACEAE Abutilon Morphological Characters Morphometric Analysis UPGMA PCoA PCA
在线阅读 免费下载
Transcriptomic analysis reveals essential microRNAs after peripheral nerve injury 认领
13
作者 Yu Wang Shu Wang Jiang-Hong He 《中国神经再生研究:英文版》 SCIE CAS 2021年第9期1865-1870,共6页
Studies have shown that microRNAs(miRNAs) mediate posttranscriptional regulation of target genes and participate in various physiological and pathological processes, including peripheral nerve injury. However, it is h... Studies have shown that microRNAs(miRNAs) mediate posttranscriptional regulation of target genes and participate in various physiological and pathological processes, including peripheral nerve injury. However, it is hard to select key miRNAs with essential biological functions among a large number of differentially expressed miRNAs. Previously, we collected injured sciatic nerve stumps at multiple time points after nerve crush injury, examined gene changes at different stages(acute, sub-acute, and post-acute), and obtained mRNA expression profiles. Here, we jointly analyzed mRNAs and miRNAs, and investigated upstream miRNAs of differentially expressed mRNAs using Ingenuity Pathway Analysis bioinformatic software. A total of 31, 42, 30, and 23 upstream miRNAs were identified at 1, 4, 7, and 14 days after rat sciatic nerve injury, respectively. Temporal expression patterns and biological involvement of commonly involved upstream miRNAs(miR-21, let-7, miR-223, miR-10 b, miR-132, miR-15 b, miR-127, miR-29 a, miR-29 b, and miR-9) were then determined at multiple time points. Expression levels of miR-21, miR-132, miR-29 a, and miR-29 b were robustly increased after sciatic nerve injury. Biological processes involving these miRNAs include multicellular organismal response to stress, positive regulation of the epidermal growth factor receptor signaling pathway, negative regulation of epithelial cell differentiation, and regulation of myocardial tissue growth. Moreover, we constructed mechanistic networks of let-7, miR-21, and miR-223, the most significantly involved upstream miRNAs. Our findings reveal that multiple upstream miRNAs(i.e., let-7, miR-21, and miR-223) were associated with gene expression changes in rat sciatic nerve stumps after nerve injury, and these miRNAs play an important role in peripheral nerve regeneration. This study was approved by the Experimental Animal Ethics Committee of Jiangsu Province of China(approval No. 20190303-18) on March 3, 2019. 展开更多
关键词 bioinformatic analysis Ingenuity Pathway Analysis mechanistic network MICRORNA peripheral nerve injury peripheral nerve regeneration RNA sequencing sciatic nerve crush
在线阅读 下载PDF
A two-dimensional limit equilibrium computer code for analysis of complex toppling slope failures 认领
14
作者 Akbar Ardestani Mehdi Amini Kamran Esmaeili 《岩石力学与岩土工程学报:英文版》 SCIE 2021年第1期114-130,共17页
Evaluation of blocky or layered rock slopes against toppling failures has remained of great concern for engineers in various rock mechanics projects.Several step-by-step analytical solutions have been developed for an... Evaluation of blocky or layered rock slopes against toppling failures has remained of great concern for engineers in various rock mechanics projects.Several step-by-step analytical solutions have been developed for analyzing these types of slope failures.However,manual application of these analytical solutions for real case studies can be time-consuming,complicated,and in certain cases even impossible.This study will first examine existing methods for toppling failure analyses that are reviewed,modified and generalized to consider the effects of a wide range of external and dead loads on slope stability.Next,based on the generalized presented formulae,a Windows form computer code is programmed using Visual C#for analysis of common types of toppling failures.Input parameters,including slope geometry,joint sets parameters,rock and soil properties,ground water level,dynamic loads,support anchor loads as well as magnitudes and forms of external forces,are first loaded into the code.The input data are then saved and used to graphically draw the slope model.This is followed by automatic identification of the toppling failure mode and a deterministic analysis of the slope stability against this failure mode.The results are presented using a graphical approach.The developed code allows probabilistic introduction of the input parameters via probability distribution functions(PDFs)and thus a probabilistic analysis of the toppling failure modes using Monte-Carlo simulation technique.This allows calculation of the probability of slope failure.Finally,several published case studies and typical examples are analyzed with the developed code.The outcomes are compared with those of the main references to assess the performance and robustness of the developed computer code.The comparisons demonstrate good agreement between the results. 展开更多
关键词 Rock slope Toppling failures Analytical solution Windows form application Deterministic analysis Probabilistic analysis
在线阅读 下载PDF
Identification of predictive MRI and functional biomarkers in a pediatric piglet traumatic brain injury model 认领
15
作者 Hongzhi Wang Emily W.Baker +3 位作者 Abhyuday Mandal Ramana M.Pidaparti Franklin D.West Holly A.Kinder 《中国神经再生研究:英文版》 SCIE CAS 2021年第2期338-344,共7页
Traumatic brain injury(TBI) at a young age can lead to the development of long-term functional impairments. Severity of injury is well demonstrated to have a strong influence on the extent of functional impairments;ho... Traumatic brain injury(TBI) at a young age can lead to the development of long-term functional impairments. Severity of injury is well demonstrated to have a strong influence on the extent of functional impairments;however, identification of specific magnetic resonance imaging(MRI) biomarkers that are most reflective of injury severity and functional prognosis remain elusive. Therefore, the objective of this study was to utilize advanced statistical approaches to identify clinically relevant MRI biomarkers and predict functional outcomes using MRI metrics in a translational large animal piglet TBI model. TBI was induced via controlled cortical impact and multiparametric MRI was performed at 24 hours and 12 weeks post-TBI using T1-weighted, T2-weighted, T2-weighted fluid attenuated inversion recovery, diffusion-weighted imaging, and diffusion tensor imaging. Changes in spatiotemporal gait parameters were also assessed using an automated gait mat at 24 hours and 12 weeks post-TBI. Principal component analysis was performed to determine the MRI metrics and spatiotemporal gait parameters that explain the largest sources of variation within the datasets. We found that linear combinations of lesion size and midline shift acquired using T2-weighted imaging explained most of the variability of the data at both 24 hours and 12 weeks post-TBI. In addition, linear combinations of velocity, cadence, and stride length were found to explain most of the gait data variability at 24 hours and 12 weeks post-TBI. Linear regression analysis was performed to determine if MRI metrics are predictive of changes in gait. We found that both lesion size and midline shift are significantly correlated with decreases in stride and step length. These results from this study provide an important first step at identifying relevant MRI and functional biomarkers that are predictive of functional outcomes in a clinically relevant piglet TBI model. This study was approved by the University of Georgia Institutional Animal Care and Use Committee(AUP: 展开更多
关键词 controlled cortical impact gait analysis linear regression magnetic resonance imaging motor function pediatric pig model principal component analysis traumatic brain injury
在线阅读 下载PDF
Evaluating Methods for Dealing with Missing Outcomes in Discrete-Time Event History Analysis: A Simulation Study 认领
16
作者 Shahab Jolani Nils L. M. van de Ven +1 位作者 Maryam Safarkhani Mirjam Moerbeek 《统计学期刊(英文)》 2021年第1期36-76,共41页
<strong>Background:</strong><span style="font-family:;" "=""><span style="font-family:Verdana;"> In discrete-time event history analysis, subjects are measure... <strong>Background:</strong><span style="font-family:;" "=""><span style="font-family:Verdana;"> In discrete-time event history analysis, subjects are measured once each time period until they experience the event, prematurely drop out, or when the study concludes. This implies measuring event status of a subject in each time period determines whether (s)he should be measured in subsequent time periods. For that reason, intermittent missing event status causes a problem because, unlike other repeated measurement designs, it does not make sense to simply ignore the corresponding missing event status from the analysis (as long as the dropout is ignorable). </span><b><span style="font-family:Verdana;">Method:</span></b><span style="font-family:Verdana;"> We used Monte Carlo simulation to evaluate and compare various alternatives, including event occurrence recall, event (non-)occurrence, case deletion, period deletion, and single and multiple imputation methods, to deal with missing event status. Moreover, we showed the methods’ performance in the analysis of an empirical example on relapse to drug use. </span><b><span style="font-family:Verdana;">Result:</span></b><span style="font-family:Verdana;"> The strategies assuming event (non-)occurrence and the recall strategy had the worst performance because of a substantial parameter bias and a sharp decrease in coverage rate. Deletion methods suffered from either loss of power or undercoverage</span><span style="color:red;"> </span><span style="font-family:Verdana;">issues resulting from a biased standard error. Single imputation recovered the bias issue but showed an undercoverage estimate. Multiple imputations performed reasonabl</span></span><span style="font-family:Verdana;">y</span><span style="font-family:;" "=""><span style="font-family:Verdana;"> with a negligible standard error bias leading to a gradual decrease in power. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> On the basis of the simulation resu 展开更多
关键词 Missing Data DELETION IMPUTATION Retrospective Observations Survival Analysis
在线阅读 免费下载
Interpreting Nestedness and Modularity Structures in Affiliation Networks: An Application in Knowledge Networks Formed by Software Project Teams 认领
17
作者 Jorge Luiz dos Santos Renelson Ribeiro Sampaio 《社交网络(英文)》 2021年第1期1-18,共18页
An understanding of the knowledge creation and diffusion process in the organizational context is extremely relevant. Because from this understanding, organizations can restructure processes, reorient teams and implem... An understanding of the knowledge creation and diffusion process in the organizational context is extremely relevant. Because from this understanding, organizations can restructure processes, reorient teams and implement methodologies to assist in the construction of an evolutionary process of knowledge creation and diffusion aimed at sustainable growth and innovation. The theory of complex social networks has been applied in several fields to help understand organizational cognitive processes. However, these approaches still insipiently consider the analysis of the nestedness and modularity of the studied networks. In this article, we presented an approach that sought to identify patterns of nestedness and modularity in networks of affiliation of people in projects in the organizational context. The study sought to identify these patterns in affiliation networks in a public organization providing information technology services in the period from 2006 to 2013. The detection of these patterns was performed using the NODF (Nestedness metric based on Overlap and Decreasing Fill) algorithm described by <a href="#ref1">[1]</a>. The nestedness and modularity metrics can influence patterns of knowledge creation and diffusion in formal and informal networks constituted for the execution of projects in organizations. This study showed that the network structures of the organization during the study period presented a high degree of nestedness, and it was possible to identify combined structures of nestedness and modularity. 展开更多
关键词 Social Network Analysis Affiliation Networks MODULARITY NESTEDNESS
在线阅读 免费下载
Uncovering and Displaying the Coherent Groups of Rank Data by Exploratory Riffle Shuffling 认领
18
作者 Vartan Choulakian Jacques Allard 《统计学期刊(英文)》 2021年第1期178-212,共35页
Let <i><span>n</span></i><span> respondents rank order </span><i><span>d</span></i><span> items, and suppose that <img src="Edit_c36450fa-1b61-... Let <i><span>n</span></i><span> respondents rank order </span><i><span>d</span></i><span> items, and suppose that <img src="Edit_c36450fa-1b61-4116-be40-5bede8274d30.bmp" alt="" /></span><span><span>. Our main task is to uncover and display the structure of the observed rank data by an exploratory riffle shuffling procedure which sequentially decomposes the n voters into a finite number of coherent groups plus a noisy group: where the noisy group represents the outlier voters and each coherent group is composed of a finite number of coherent clusters. We consider exploratory riffle shuffling of a set of items to be equivalent to optimal two blocks seriation of the items with crossing of some scores between the two blocks. A riffle shuffled coherent cluster of voters within its coherent group is essentially characterized by the following facts: 1) Voters have identical first TCA factor score, where TCA designates taxicab correspondence analysis, an L</span><sub><span>1</span></sub><span> variant of corresponden</span><span>ce analysis;2) Any preference is easily interpreted as riffle shuffling of its items;3) The nature of different riffle shuffling of items can be seen in the structure of the contingency table of the first-order marginals constructed from the Borda scorings of the voters;4) The first TCA factor scores of the items of a coherent cluster are interpreted as Borda scale of the items. We also introduce a crossing index, which measures the extent of crossing of scores of voters between the two blocks seriation of the items. The novel approach is explained on the benchmarking SUSHI data set, where we show that this data set has a very si</span><span>mple structure, which can also be communicated in a tabular form.</span></span> 展开更多
关键词 Borda Score and Scale Exploratory Riffle Shuffle Coherent Group Coherent Cluster Crossing Index Taxicab Correspondence Analysis
在线阅读 免费下载
Comparison of Conventional and Advanced Exergy Analysis for Dual-Loop Organic Rankine Cycle used in Engine Waste Heat Recovery 认领
19
作者 WANG Zhiqi HU Yanhua XIA Xiaoxia 《热科学学报:英文版》 SCIE EI CAS 2021年第1期177-190,共14页
At present,the dual-loop organic Rankine cycle(DORC)is regarded as an important solution to engine waste heat recovery(WHR).Compared with the conventional exergy analysis,the advanced exergy analysis can better descri... At present,the dual-loop organic Rankine cycle(DORC)is regarded as an important solution to engine waste heat recovery(WHR).Compared with the conventional exergy analysis,the advanced exergy analysis can better describe the interactions between system components and the irreversibility caused by economic or technical limitations.In order to systematically study the thermodynamic performance of DORC,the conventional and advanced exergy analyses are compared using an inline 6-cylinder 4-stroke turbocharged diesel engine.Meanwhile,the sensitivity analysis is implemented to further investigate the influence of operating parameters on avoidable-endogenous exergy destruction.The analysis result of conventional exergy analysis demonstrates that the priorities for the components that should be improved are in order of the high-temperature evaporator,the low-temperature turbine,the first low-temperature evaporator and the high-temperature condenser.The advanced exergy analysis result suggests that the avoidable exergy destruction values are the highest in the low-temperature turbine,the high-temperature evaporator and the high-temperature turbine because they have considerable endogenous-avoidable exergy destruction.The sensitivity analysis indicates that reducing the evaporation pinch point and raising the turbine efficiency can decrease the avoidable exergy destruction. 展开更多
关键词 advanced exergy analysis conventional exergy analysis dual-loop organic Rankine cycle(DORC) internal combustion engine waste heat recovery(WHR)
A probabilistic-based method to evaluate hygrothermal performance of an internally insulated brick wall 认领
20
作者 Jianhua Zhao Jianshun Zhang +1 位作者 John Grunewald Shuo Feng 《建筑模拟(英文)》 SCIE EI 2021年第2期283-299,共17页
Uncertainty exists in many aspects of building simulation.A deterministic hygrothermal analysis may not sufficiently give a reliable guidance if a number of input variables are subject to uncertainty.In this paper,a p... Uncertainty exists in many aspects of building simulation.A deterministic hygrothermal analysis may not sufficiently give a reliable guidance if a number of input variables are subject to uncertainty.In this paper,a probabilistic-based method was developed to evaluate the hygrothermal performance of building components.The approach accounts for the uncertainties from model inputs and propagates them to the outputs through the simulation model,thus it provides a likelihood of performance risk.Latin hypercube sampling technique,incorporated with correlation structure among the inputs,was applied to generate the random samples that follows the intrinsic relations.The performance of an internally insulated masonry wall was evaluated by applying the proposed approach against different criteria.Thermal performance,condensation and mould growth potential of the renovated wall can overall satisfy the requirements stipulated in multifold standards.The most influential inputs were identified by the standardized regression sensitivity analysis and partial correlation technique.Both methods deliver the same key parameters for the single and time-dependent output variables in the case study.The probabilistic method can provide a comprehensive risk analysis and support the decision-maker and engineer in the design and optimization of building components. 展开更多
关键词 probabilistic approach hygrothermal performance building component uncertainty analysis sensitivity analysis
上一页 1 2 250 下一页 到第
使用帮助 返回顶部 意见反馈