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Disturbance history,species diversity,and structural complexity of a temperate deciduous forest

Journal of Forestry Research 2020年第2期31卷 397-414页

作者： Jonathan D.Goode Carson R.Barefoot Justin L.hart Daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Stand structural complexity enhancement is an increasingly popular management objective,especially on public *** stand structures are hypothesized to support a relatively high degree of native forest diversity and be more resistant and resilient to *** structures are characterized by the presence of deadwood and heterogeneity of tree-size classes and tree *** little is known about how discrete disturbance events affect structural complexity and compositional diversity in Quercus-dominated stands at fine spatial scales(***).We established 200.05 ha fixed-radius plots on the Sipsey Wilderness of William *** National Forest in northern Alabama to quantify woody plant species composition and *** were mapped on each plot to quantify overstory structural complexity and compositional *** extracted two cores from all canopy Quercus spp.C 5 cm diameter at breast height to quantify age,recruitment pulses,and reconstruct canopy disturbance *** species diversity in the sampled area was 1.75 for trees,2.08 for saplings,and 1.69 for *** alba had the greatest basal area,and Ostrya virginiana had the highest *** stand exhibited a reverse J-shaped distribution with a q-factor of *** oldest Quercus dated to 1795,and the largest recruitment pulse occurred in the *** mean return interval for intermediateseverity disturbance was 38 *** we documented no relationships between disturbance frequency and compositional diversity at the neighborhood scale(0.05 ha),less frequent disturbance was associated with higher structural complexity(r^2=0.258,p=0.026)at the neighborhood *** suggest that localized disturbance increases species diversity and structural complexity,but these processes are manifest at the stand level and not at the neighborhood *** conclude that the spatial variability(***,shape,orientation,microsite conditions)is likel

关键词： Canopy gap Quercus(oak) Stand development Succession

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Macro-and microcirculation patterns of intrahepatic blood flow changes in patients with hereditary hemorrhagic telangiectasia

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World Journal of Gastroenterology 2017年第3期23卷 486-495页

作者： Roland C Schelker Ana P Barreiros Christina hart Wolfgang Herr Ernst-Michael Jung Department of Internal Medicine III Hematology and OncologyUniversity Hospital of Regensburg93051 RegensburgGermany Ernst-Michael Jung Department of RadiologyUniversity Hospital of Regensburg93051 RegensburgGermany

AIM To evaluated vascular dynamic processes in the liver of hereditary hemorrhagic telangiectasia(HHT) patients by ultrasound(US) considering quantitative analytic methods. METHODS The imaging features on US and contrast-enhanced ultrasound(CEUS) in 18 patients diagnosed with HHT were retrospectively analyzed. Regarding CEUS, realtime contrast harmonic imaging and sulfur hexafluoridefilled microbubbles were used. RESULTS HVa Ms were identified in all 18 patients. By US, the two major Caselitz criteria could be detected in 55.6% patients. "Color spots" were detected in 72.2% of the cases. Respecting sonographic grading criteria by Buscarini, grade 3 could be demonstrated most frequent(40%). By CEUS, all the patients showed quick and early hyperenhancement during the arterial phase. Significant lowest time to peak(TTP) and highest area under the curve(AUC) values were identified in the hepatic artery(TTP: 69.8%; AUC: 100%) and highest TTP and lowest AUC in the hepatic parenchyma and the portal vein. CONCLUSION For the first time we analyzed CEUS findings of a group of HHT patients regarding macro- and microcirculation. Our data demonstrate significant differences in TTP and AUC values in the four selected regions: hepatic artery, shunt region, portal vein and hepatic parenchyma.

关键词： Hereditary hemorrhagic telangiectasia Intrahepatic shunts Contrast-enhanced ultrasound Time-intensity-curve

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The Crossing Number of Two-Maps on Orientable Surfaces

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Journal of Mathematical Research and Exposition 2011年第4期31卷 643-648页

作者： Yong Xiang WU hart REN Tu XU Department of Mathematics Education Resource Center Ningbo Polytechnic Zhejiang 315800 P. R. China Department of Mathematics East China Normal University Shanghai 200062 P. R. China

In this paper, we discuss the crossing numbers of two one-vertex maps on orientable surfaces. By using a reductive method, we give the crossing number of two one-vertex maps with one face on an orientable surface and the crossing number of a one-vertex map with one face and a one-vertex map with two faces on an orientable surface. This provides a lower bound for the crossing number of two general maps on an orientable surface.

关键词： crossing number embedding orientable surface.

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Biomarkers of Aging: An Overview

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Biomedical and Environmental Sciences 1991年第Z1期 130-133页

作者： ANGELO TURTURRO,RONALD W.hart National Center for Toxicological Research Jefferson National Center for Toxicological Research Jefferson Akansas 72079 Akansas 72079

INTRODUCTION Although aging has often been thought of as some intrinsic, immutable process, an alternative is to approach aging as a toxic endpoint resulting from a combination of endogenous and exogenous damage. Aging is then defined as consisting of a combination of functional declines observed in every organism system, occurring at different ages for different systems (Shock, 1985). One measure of this decline is death, and mortality is often used as a surrogate for aging. The sources of endogenous

关键词： Biomarkers of Aging An Overview

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Multi-scale drivers of soil resistance predict vulnerability of seasonally wet meadows to trampling by pack stock animals in the Sierra Nevada,USA

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Ecological Processes 2020年第1期9卷 364-377页

作者： Joy S.Baccei Mitchel P.McClaran Tim J.Kuhn Stephen C.hart Environmental Systems Graduate Group University of CaliforniaMercedCA 95343USA UC Merced Vernal Pools and Grassland Reserve UC Merced Natural Reserve SystemMercedCA 95343USA School of Natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Resources Management and Science Yosemite National ParkEl PortalCA 95318USA Department of Life&Environmental Sciences and Sierra Nevada Research Institute University of CaliforniaMercedCA 95343USA.

Background:Meadow ecosystems have important ecological functions and support socioeconomic services,yet are subject to multiple stressors that can lead to rapid *** the Sierra Nevada of the western USA,recreational pack stock(horses and mules)use in seasonally wet mountain meadows may lead to soil trampling and meadow degradation,especially when soil water content is high and vegetation is ***:In order to improve the ability to predict meadow vulnerability to soil disturbance from pack stock use,we measured soil resistance(SR),which is an index of vulnerability to trampling disturbance,at two spatial scales using a stratified-random sampling *** then compared SR to several soil and vegetation explanatory variables that were also measured at the two spatial scales:plant community type(local scale)and topographic gradient class(meadow scale).Results:We found that local-scale differences in drivers of SR were contingent on the meadow scale,which is important because multiple spatial scale evaluation of ecological metrics provides a broader understanding of the potential controls on ecological processes than assessments conducted at a single spatial *** also found two contrasting explanatory models for drivers of SR at the local scale:(1)soil gravimetric water content effects on soil disaggregation and(2)soil bulk density and root mass influence on soil *** resistance was insufficient to sustain pack stock use without incurring soil deformation in wet plant communities,even when plant cover was maximal during a major ***:Our study provides new information on seasonally wet meadow vulnerability to trampling by pack stock animals using multi-scale drivers of SR,including the contrasting roles of soil disaggregation,friction,and *** work aims to inform meadow management efforts in the Sierra Nevada and herbaceous ecosystems in similar regions that are subject to seasonal soil saturation and livestock u

关键词： Hydrogeomorphic classification Hydrologic regime Pack stock Plant communities Soil properties Soil strength

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HoLEP does not affect the overall sexual function of BPH patients： a prospective study

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Asian Journal of Andrology 2014年第6期16卷 873-877页

作者： Sung hart Kim Hyung-Kook Yang Hahn-Ey Lee Jae-Seung Paick Seung-June Oh Department of Urology Prostate Cancer Center National Cancer Center Goyang Korea Department of Epidemiology and Statistics and Cancer Policy Branch of National Cancer Control Research Institute National Cancer Center Goyang Korea Department of Urology Seoul National University Hospital Seoul Korea.

We aimed to prospectively evaluate the influence of holmium laser enucleation of the prostate （HoLEP） on the overall postoperative sexual function of benign prostatic hyperplasia （BPH） patients with lower urinary tract symptoms （LUTS） and to explore the relationship between sexual function and LUTS. From January 2010 to December 2011, sixty sexually active consecutive patients with BPH who underwent HoLEP were prospectively enrolled in the study. All patients filled out the Male Sexual Health Questionnaire （MSHQ） for evaluation of their overall sexual function and the International Prostatic Symptom Score （IPSS） for pre- and post-operative 6 months evaluation of their voiding symptoms. The LUTS and sexual function changes were statistically analyzed. The preoperative and 6 months postoperative status of the patients was compared using uroflowmetry and IPSS questionnaires. The analysis revealed significant improvements following HoLEP. Among the sub-domains of the MSHQ, postoperative sexual function, including erection, ejaculation, sexual satisfaction, anxiety or sexual desire, did not significantly change after HoLEP （P 〉 0.05）, whereas satisfaction scores decreased slightly due to retrograde ejaculation in 38 patients （63.3%）. Sexual satisfaction improved significantly and was correlated with the improvements of all LUTS and the quality-of-life （QoL） domains in IPSS after surgery （QoL; relative risk [RR]： -0.293; total symptoms, RR： -0.411; P 〈 0.05）. The nocturia score was associated with the erectile function score （odds ratio 0.318, P = 0.029）. The change in ejaculatory scores did not show significant association with IPSS scores. HoLEP did not influence overall sexual function, including erectile function. In addition, sexual satisfaction improved in proportion with the improvement of LUTS.

关键词： benign prostatic hyperplasia ejaculation erectile dysfunction lasers prostatectomy sex disorders

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Weighted Polar Decomposition

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Journal of Mathematical Research and Exposition 2009年第5期29卷 787-798页

作者： YANG Hu LI hart Yu College of Mathematics and Physics Chongqing University Chongqing 400044 China

In this paper,a new matrix decomposition called the weighted polar decomposition is *** uniqueness theorems of weighted polar decomposition are presented,and the best approximation property of weighted unitary polar f... 详细信息

关键词： generalized polar decomposition weighted polar decomposition weighted unitary polar factor weighted norm perturbation bound.

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Conceptual design of the HIRFL-CSR external-target experiment

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Science China(Physics,Mechanics & Astronomy) 2017年第1期60卷 65-71页

作者： LiMing Lu hart Yi ZhiGang Xiao Ming Shao Song Zhang GuoQing Xiao Nu Xu Department of Physics Tsinghua University Beijing 100084 China Collaborative Innovation Center of Quantum Matter Beijing 100084 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China Institute of Particle Physics Central China Normal University Wuhan 430079 China

One of the main purposes of heavy-ion collisions over a wide range of beam energy is to study the bulk properties of strong interaction matter and understand the Quantum Chromo Dy- namics （QCD） phase diagram, which carries wealth of infor- mation of the phase transition and the possibly existing criti- cal point of the strongly interacting system [1]. Such system exists as hadron gases at lower temperature and low baryon density. By increasing the temperature or density, the bound- ary of the hadrons disappears and the confined quarks move freely in the whole system.

关键词： MRPC Conceptual design of the HIRFL-CSR external-target experiment HIRFL TPC CSR

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Xi Jinping＇s Methodology for the Governance of China

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Qiu Shi 2015年第3期7卷 53-59页

作者： hart Lingwiang Deputy Provost School of the CPC Central Committee.

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Social media video analysis methodology for sarin exposure

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Forensic Sciences Research 2022年第2期7卷 279-284页

作者： Sadik Toprak Emine Yilmaz Can Bulent Altinsoy John hart Zekeriya Dogan Mustafa Ozcetin Department of Forensic Medicine Istanbul UniversityIstanbulTurkey Department of Medical Pharmacology Bulent Ecevit UniversityZonguldakTurkey Department of Pulmonary Medicine Bulent Ecevit UniversityZonguldakTurkey James Martin Center for Nonproliferation Studies MontereyCAUSA Department of Civil Engineering Bulent Ecevit UniversityZonguldakTurkey Department of Pediatrics Istanbul UniversityIstanbulTurkey

As social media becomes increasingly ubiquitous,many events are recorded and released on social media platforms,including chemical weapon *** develop an objective tool in order to evaluate brief and unstructured social media videos for analysing sarin exposure from a civilian medical pathology *** developed and validated this new questionnaire using a standardized procedure that includes content domain specification,item pool generation,content validity evaluation,a pilot study,and assessment of reliability and *** total,51 sarin attacks and 48 matched videos were ***’s a for all 20 items was 0.75,which indicates adequate internal *** test–retest reliability was 0.96,which indicates good internal *** inter-observer intraclass correlation coefficient was *** verifying sampling adequacy with the Kaiser–Meyer–Olkin measure and the factorability of the items with Barlett’s test of sphericity,a factor analysis was *** to the principal axis factoring,a six-factor solution explained 51.86%of the total *** receiver-operating characteristic curve analysis showed that the Video Score Questionnaire has a sensitivity of 0.817,a specificity of 0.478,and an efficiency of ***,the Video Score Questionnaire is reliable and valid for evaluating sarin attacks from brief and unstructured social media videos.

关键词： Forensic sciences social media sarin scale questionnaire chemical weapon nerve agent YouTube

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