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Elements of disturbance that affect epiphyte vitality in a temperate rainforest:an experimental approach

Journal of Plant Ecology 2019年第2期12卷 306-313页

作者： Nalini M.Nadkarni Kevin d.Kohl department of Biology University of Utah257 South 1400 EastSalt Lake CityUT 84112USA department of Biological Sciences University of Pittsburgh403B Clapp Hall4249 Fifth AvenuePittsburghPA 115260USA

Aims Epiphytes are an abundant and diverse component of many wet temperate forests and have significant roles in ecosystem *** is known about the processes and rates of their death and decomposition when they fall from the canopy,which limits our understanding of their role in forest carbon sequestration and nutri-ent *** the temperate rainforest of the Quinault River Valley,Washington State,our aim was to test hypotheses regarding four elements of disturbance that might contribute to their *** We established set of experiments in which we placed samples of canopy epiphytes and their branch segments:(i)in the canopy versus forest floor microenvironment(stratum);(ii)attached to live versus dead branch substrates;(iii)subjected to physical disruption and‘jarring’;and(iv)in direct versus indirect con-tact with the forest *** the 2-year study,we assigned a non-destructive‘vitality index’(based on color and appar-ent mortality and dryness)to each sample every 2-3 months to compare effects of the experimental treatments and analyzed with a statistical model and post hoc pairwise comparisons of *** Findings The canopy versus ground stratum and live/dead branch status sig-nificantly affected epiphyte *** of physical disruption and ground contact were not *** were seasonal effects(low vitality during the sampling times in the summer,revitalization upon sampling times in the winter)for all treatments except samples in contact with the *** implication of these results relates to effects of climate change,which is predicted to shift to hotter,drier summers and wetter *** change may affect forest dynamics and nutrient cycling in unpredictable *** also point to future experiments to understand biotic and abiotic effects on epiphyte disturbance and dynamics.

关键词： disturbance epiphytes forest canopy forest dynamics moss olympic rainforest

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Analysis of monitored ground support and rock mass response in a longwall tailgate entry

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International Journal of Mining Science and Technology 2018年第1期28卷 43-51页

作者： G.S.Esterhuizen d.F.Gearhart I.B.Tulu NIoSH Pittsburgh Mining Research division PittsburghPA 15236USA West Virginia University MorgantownWV 26506USA

A comprehensive monitoring program was conducted to measure the rock mass displacements, support response, and stress changes at a longwall tailgate entry in West *** was initiated a few days after development of the gateroad entries and continued during passage of the longwall panels on both sides of the *** included overcore stress measurements of the initial stress within the rock mass, changes in cable bolt loading, standing support pressure, roof deformation, rib deformation,stress changes in the coal pillar, and changes in the full three-dimensional stress tensor within the rock mass at six locations around the monitoring *** the passage of the first longwall, stress measurements in the rock and coal detected minor changes in loading while minor changes were detected in roof *** a result of the relatively favorable stress and geological conditions, the support systems did not experience severe loading or rock deformation until the second panel approached within 10–15 m of the instrumented *** reaching the peak loading at about 50–75 mm of roof sag, the cable bolts started to unload, and load was transferred to the standing *** standing support system was able to maintain an adequate opening inby the shields to provide ventilation to the first crosscut inby the face, as *** results were used to calibrate modeled cable bolt response to field data, and to validate numerical modeling procedures that have been developed to evaluate entry support *** is concluded that the support system was more than adequate to control the roof of the tailgate up to the longwall face *** monitoring results have provided valuable data for the development and validation of support design strategies for longwall tailgate entries.

关键词： Longwall mining Support Tailgate Monitoring Coal mining

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Common genetic variants in the TP53 pathway and their impact on cancer

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Journal of Molecular Cell Biology 2019年第7期11卷 578-585页

作者： Thibaut Barnoud Joshua L.d.parris Maureen E.Murphy Program in Molecular and Cellular oncogenesis The Wistar InstitutePhiladelphiaPA 19104USA Cell and Molecular Biology Program Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104USA

The TP53 gene is well known to be the most frequently mutated gene in human *** addition to mutations,there are > 20 different coding region single-nucleotide polymorphisms (SNPs) in the TP53 gene,as well as SNPs in MdM2,the negative regulator of *** of these SNPs are known to alter p53 pathway *** makes p53 rather unique among cancer-critical genes,*** coding regions of other cancer-critical genes like Ha-Ras,RB,and PI3KCA do not have non-synonymous coding region SNPs that alter their function in *** next frontier in p53 biology will consist of probing which of these coding region SNPs are moderately or strongly pathogenic and whether they influence cancer risk and the efficacy of cancer *** challenge after that will consist of determining whether we can tailor chemotherapy to correct the defects for each ofthese *** we review the SNPs in TP53 and MdM2 that show the most significant impact on cancer and other *** also propose avenues for how this information can be used to better inform personalized medicine approaches to cancer and other diseases.

关键词： p53 Pro47Ser Pro72Arg paS MdM2 SNP309

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Bidirectional relationships of physical activity and gross motor skills before and after summer break:Application of a cross-lagged panel model

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Journal of Sport and Health Science 2022年第2期11卷 244-251页

作者： Ryan d.Burns Yang Bai Wonwoo Byun Taylor E.Colotti Christopher d.Pfledderer Sunku Kwon Timothy A.Brusseau department of Health Kinesiologyand RecreationUniversity of UtahSalt Lake CityUT 84112USA

Background:Gross motor skills are postulated to have a bidirectional relationship with physical activity(pa);however,no study has tested this relationship before and after a summer *** purpose of this study was to examine the bidirectional relationships between school pa and gross motor skills in children before and after a summer ***:participants were a sample of 440 children recruited from 3 low-income schools(age=8.9±1.2 years,mean±Sd).pa was assessed as average school-day step counts using Yamax digiWalker pedometers(Yamasa Tokei Keiki,Tokyo,Japan)worn for 5 consecutive school *** motor skills were assessed using the Test for Gross Motor development,3 rd *** were collected at 2 timepoints:at the end of spring semester(T1)and at the beginning of the subsequent fall semester(T2).An age-and body mass index-adjusted cross-lagged model was employed to relate T1 school step counts with T2 gross motor skills and T1 gross motor skills with T2 school step ***:T1 gross motor skills significantly predicted T2 school step counts(β=0.24,95%confidence interval(95%CI):0.08-0.40,p=0.003);however,Tl school step counts did not predict T2 gross motor skills(β=0.04,95%CI:-0.06 to 0.14,p=0.445).The model explained 35.4%and 15.9%of the variances of T2 gross motor skills and T2 school step counts,*** analyses indicated that these relationships were driven primarily by ball ***:The relationship between gross motor skills and school pa was not bidirectional;however,higher gross motor skills,specifically ball skills,predicted higher school pa after a 3-month summer break.

关键词： Children Motor competence Physical activity Schools

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小麦背景中簇毛麦染色质的鉴定(英文)

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四川大学学报（自然科学版） 2000年第S1期37卷 91-95页

作者：余懋群陈静邓光兵 M.Cerbah 马欣荣 o.panaud S.Yakovlev 中国科学院成都生物研究所成都610041 Universite paris-Sud Laboratoire d’Evolutionet Systematique

作者应用染色体组原位杂交 (FISH) ,C 带和酸性聚丙烯酰胺凝胶电泳 (A paGE)技术对杂交选育的抗白粉病小麦簇毛麦附加系“95 0 39” ,以及利用 6VS/ 6AL易位系回交转育的抗白粉病后代植株染色体组成进行分析 ,结果表明 ,“95 0 39”... 详细信息

作者应用染色体组原位杂交 (FISH) ,C 带和酸性聚丙烯酰胺凝胶电泳 (A paGE)技术对杂交选育的抗白粉病小麦簇毛麦附加系“95 0 39” ,以及利用 6VS/ 6AL易位系回交转育的抗白粉病后代植株染色体组成进行分析 ,结果表明 ,“95 0 39”中附加染色体为簇毛麦染色体 6V短臂 ,该臂携有抗白粉病基因和高蛋白含量基因 ,是利用染色体显微操作技术进行基因分离、克隆研究的极好材料。 6VS/ 6AL易位染色体已被转移到四川推广小麦品种“川育 1 2”遗传背景中。通过染色体原位杂交显示 ,有丝分裂间期、前期 ,同源的 6VS/ 6AL易位染色体呈相邻排列 ,而不是随机地分布在整个细胞中。

关键词： A-paGE C-带 GISH 端体附加系易位系

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Effects of laparoscopic cholecystectomy on lung function:A systematic review

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World Journal of Gastroenterology 2014年第46期20卷 17603-17617页

作者： George d Bablekos Stylianos A Michaelides Antonis Analitis Konstantinos A Charalabopoulos department of Experimental Physiology Medical SchoolDemocritous University of Thrace68100 AlexandroupolisGreece Technological Educational Institute of Athens 12243 EgaleoGreece First Thoracic Medicine department "Sismanogleio" General Hospital15126 AthensGreece department of Hygiene Epidemiology and Medical StatisticsMedical SchoolNational and Kapodistrian University of Athens11527 GoudiAthensGreece

AIM: To present and integrate findings of studies investigating the effects of laparoscopic cholecystectomy on various aspects of lung function.

关键词： Laparoscopic open procedure Cholecystectomy Respiratory function Respiratory physiology

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Modeling simulation and experimental validation for mold filling process

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中国有色金属学会会刊：英文版 2006年第A2期16卷 335-338,339页

作者：侯华巨东英毛红奎 d．SAITo College of Materials Science and Technology North University of China Taiyuan 030051 China department of Mechanical Engineering Saitama Institute of Technology Fusaiji Saitama369-0239 Japan

Based on the continuum equation, momentum conservation and energy conservation equations, the numerical model of turbulent flow filling was introduced; the 3-d free surface vof method was improved. Whether or not the numerical simulation results are reasonable, it needs corresponding experimental validations. General experimental techniques for casting fluid flow process include: thermocouple tracking location method, hydraulic simulating method, heat-resistant glass window method and X-ray observation etc. The hydraulic analogue experiment with dPIV technique is arranged to validate the fluent flow program for low-pressure casting with 0.1 X 10(5) pa and 0.6 X 10(5) pa pressure visually. By comparing the flow head, liquid surface, flow velocity, it is found that the filling pressure value influences the flow state strongly. With the increase of the filling pressure, the fluid flow state becomes'unstable, the flow head becomes higher, and the filling time is reduced. The simulated results are accordant with the observed results approximately, which can prove the reasonability of our numerical program for filling process further.

关键词：铸模浇注过程数学模型数值模拟实验验证

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