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Journal of Geographical Sciences 2022年第2期32卷 280-290页

作者：钱宏张扬建 robert e.RICKLeFS 王宪礼 Research and Collections Center Illinois State Museum1011 East Ash StreetSpringfieldIL 62703USA Key Laboratory of ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Department of Biology University of Missouri–St.LouisSt.LouisMO 63121USA Northern Forestry Centre Canadian Forest ServiceNatural Resources Canada5320-122nd StreetEdmontonAB T6H 3S5Canada Department of Renewable Resources University of Alberta751 General Service Building EdmontonAB T6G 2H1Canada

Biologists have considered both winter coldness and temperature seasonality as major determinants of the northern limits of plants and animals in the Northern Hemisphere,which in turn drive the well-known latitudinal diversity ***,few studies have tested which of the two climate variables is the primary *** this study,we assess whether winter coldness or temperature seasonality is more strongly associated with the northern latitudinal limits of tree species and with tree species richness in North *** species were recorded in each of 1198 quadrats of 110 km×110 km in North *** used correlation and regression analyses to assess the relationship of the latitude of the northern boundary of each species,and of species richness per quadrat,with winter coldness and temperature *** richness was analyzed within 38 longitudinal,i.e.,north-south,bands(each being>1100 km long and 110 km wide).The latitudes of the northern range limits of tree species were three times better correlated with minimum temperatures at those latitudes than with temperature *** average,minimum temperature and temperature seasonality together explained 81.5%of the variation in the northern range limits of the tree species examined,and minimum temperature uniquely explained six-fold(33.7%versus 5.8%)more of this variation than did temperature *** of tree species richness with minimum temperatures were stronger than correlations with temperature seasonality for most of the longitudinal bands *** to temperature seasonality,winter coldness is more strongly associated with species distributions at high latitudes,and is likely a more important driver of the latitudinal diversity gradient.

关键词： cold tolerance latitudinal diversity gradient minimum temperature temperature seasonality temperature variation trees tropical conservatism hypothesis

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effect of losing a fight on later agonistic behavior toward unfamiliar conspecifics in male Syrian hamsters

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Current Zoology 2011年第4期57卷 449-452页

作者： Javier DeLBARCO-TRILLO robert e. JOHNSTON Comell University Department of Psychology Uris Hall Ithaca NY 14853 USA

In many species, agonistic interactions result in social relationships that are stable over time. In Syrian hamsters, two unfamiliar males that are placed together will fight vigorously and a clear winner/loser relationship is usually established. In subsequent interactions, the loser will flee soon after detecting the familiar winner. Here we tested the hypothesis that losing a fight with a conspecific will affect future agonistic interactions not only toward that individual (i.e., the familiar winner) but also toward unfamiliar conspecifics. To test this hypothesis we paired two Syrian hamster males in three trials on one day in which the loser had the opportunity to escape the winner. The next day the loser was paired with an unfamiliar male, also for three trials. If he lost again, he was tested on a third day with a third unfamiliar male. Subjects were those males that were losers on all three days. The latency to escape on the first trial on Days 2 and 3 was significantly shorter than on the first trial on Day 1, indicating that losing against the first male affected the response toward unfamiliar males. However, the latency to escape on the first trial on Days 2 and 3 was significantly longer than that on the third trial on the preceding day, indicating that a loser treats unfamiliar males differently than a familiar winner. These results suggest that a defeat during an interaction with one male affects later agonistic behavior towards other, unfamiliar males.

关键词：叙利亚男性仓鼠行为相互作用社会关系审判测试

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The impact of macroalgae on mean and turbulent flow fields

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Journal of Hydrodynamics 2015年第3期27卷 427-435页

作者： THOMAS robert e. MCLeLLAND Stuart J. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and major roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

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eastern Siberia permafrost transect(eSPT).A first stage:The Verkhoyansk Range part

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Journal of Mountain Science 2023年第6期20卷 1499-1507页

作者： robert SYSOLYATIN Svetlana KALINICHeVA Alexander FeDOROV Maria ROZHINA Melnikov Permafrost Institute Yakutsk 677010Russia

environmental and geomorphological processes in the mountainous areas of eastern Siberia is strongly conditioned by the thermal state of permafrost(permanently frozen ground).However,the scarce data about climate and weak of permafrost study have led to the unclarity of mountain permafrost condition in this *** increase in the mean annual air temperature over the past 50 years in the northeastern Siberia by various estimates is from 1.1℃to 3.3℃.So far,almost no information is available on the permafrost response to climatic changes in the *** Kolyma Route(around 2000 km length),connecting Yakutsk and Magadan that crosses 5 climatic types and more than 10 permafrost landscapes,so it seems a suitable path for establishing basic(reference)monitoring *** 12 target boreholes,on the first stage 5 boreholes up to 30 m in depth were drilled and instrumented for measuring temperature at sites adjacent to weather stations in the Verkhoyansk Range from 283 to 1288 m *** we present conception,purpose,and methods for permafrost study project with first preliminary results from the highest weather station of the east Siberia *** following research about geophysical investigations,permafrost landscape description,mapping and spatial modelling,numerical computing,physical modelling of permafrost thickness might be initiated by the eastern Siberia Permafrost Transect(eSPT)-project.

关键词： Ground temperature Mountain permafrost Temperature e monitoring Verkhoyansk Range Climate change.

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Discharge-Stage Relationship on Urban Streams evaluated at USGS Gauging Stations,***,Missouri

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Journal of earth Science 2020年第6期31卷 1133-1141页

作者： robert e.Criss David L.Nelson Department of earth and Planetary Sciences Washington UniversitySt.Louis MO 63130USA Columbia Cir Pasadena CA 91105USA

extensive USGS data tables and detailed,1 m2 Li DAR surveys are used to determine the optimal power n that relates discharge(Q)to stage(h*)above channel bottom(ho)at 39 gauging stations on small streams in the ***,Missouri area,all of which have catchments of 0.6 to 220 *** different methodologies are employed to determine both n and ho:(1)optimizing linearity in a plot of Q1/n *** stage(hL)using USGS field measurements at each site;(2)optimizing linearity in a plot of Q1/n *** using USGS rating tables at each site;(3)a mathematical inverse method applied to the same USGS rating tables;(4)use of Li DAR data on channel geometry to determine the power dependences of channel area A and hydraulic radius H on h*,combined with the Manning and rational equations to predict *** these methods,only methods 2 and 3 compare favorably,and these values compare poorly with Method 1 based on field data,and with method 4 based on theoretical and empirical *** Method 4 is predictive,it provides a useful alternative to methods 1–3 that are based on USGS field measurements,which are heavily weighted toward low *** conclude that the apparent values of n in the USGS rating tables are systematically too low for small streams.

关键词： stream gauging Li DAR topography urban flooding discharge hydrology

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Cardiac troponins in the elderly:interpretation of elevated levels

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Journal of Geriatric Cardiology 2007年第3期4卷 188-192页

作者： robert e Fromm Baylor College of Medicine Senior IntensivistVISICUinc. 2219 Dorrington Street HoustonTX 77030USA Jr

elderly patients with myocardial infarction commonly present with symptoms other than chest pain. The clinician evaluation of the elderly may rely on laboratory methods more so than in younger patients. Fortunately,advances in laboratory science have brought newer biomarkers of cardiac injury to the clinical arena including cardiac troponins I and T(cTnI,cTnT) . These regulatory components of the contractile apparatus are sensitive indicators of myocardial injury. Their central role in the current definition of acute myocardial infarction highlights their utility in the diagnosis of acute myocardial ischemic syndromes. The troponins are also released in some clinical situations where thrombotic complications of coronary artery disease and resultant acute myocardial infarction have not occurred. examples of these conditions include conditions like myocarditis,pulmonary embolism,sepsis,and acute stroke. elevated troponins in these conditions are thought to emanate from injured myocardial cells and in most circumstances have been associated with adverse outcomes. Interpretation of elevated troponin in the elderly requires consideration of other possible conditions.

关键词： acute myocardial infarction thrombolysis elderly

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experimental analysis of tip vortex cavitation mitigation by controlled surface roughness

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Journal of Hydrodynamics 2020年第6期32卷 1059-1070页

作者： Urban Svennberg Abolfazl Asnaghi robert Gustafsson Rickard e.Bensow Kongsberg Hydrodynamic Research Centre Kongsberg Maritime ABKristinehamnSweden Department of Mechanics and Maritime Sciences Chalmers University of TechnologyGothenburgSweden

This study presents results of experiments where roughness applications are evaluated in delaying the tip vortex cavitation inception of an elliptical ***-speed video recordings and laser doppler velocimetry(LDV)measurements are employed to provide further details on the cavitation behavior and tip vortex flow properties in different roughness pattern *** angular momentum measurements of the vortex core region at one chord length downstream of the tip indicate that roughness leads to a lower angular momentum compared with the smooth foil condition while the vortex core radius remains similar in the smooth and roughened *** observations show that the cavitation number for tip vortex cavitation inception is reduced by 33%in the optimized roughness pattern compared with the smooth foil condition where the drag force increase is observed to be around 2%.During the tests,no obvious differences in the cavitation inception properties of uniform and non-uniform roughness distributions are ***,the drag force is found to be higher with a non-uniform roughness distribution.

关键词： Roughness tip vortex mitigation cavitation suppression

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Research on encoding and decoding of non-binary polar codes over GF(2m)

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Digital Communications and Networks 2022年第3期8卷 359-372页

作者： Shufeng Li Mingyu Cai robert edwards Yao Sun Libiao Jin The State Key Laboratory of Media Convergence and Communication School of Information and EngineeringCommunication University of ChinaBeijing100024China The Wolfson School of Mechanical electrical and Manufacturing engineering Loughborough UniversityLeicestershireLE113TEUK James Watt School of engineering University of GlasgowG128QQScotlandUK

Binary Polar Codes (BPCs) have advantages of high-efficiency and capacity-achieving but suffer from large latency due to the Successive-Cancellation List (SCL) decoding. Non-Binary Polar Codes (NBPCs) have been investigated to obtain the performance gains and reduce latency under the implementation of parallel architectures for multi-bit decoding. However, most of the existing works only focus on the Reed-Solomon matrix-based NBPCs and the probability domain-based non-binary polar decoding, which lack flexible structure and have a large computation amount in the decoding process, while little attention has been paid to general non-binary kernel-based NBPCs and Log-Likelihood Ratio (LLR) based decoding methods. In this paper, we consider a scheme of NBPCs with a general structure over GF(2m). Specifically, we pursue a detailed Monte-Carlo simulation implementation to determine the construction for proposed NBPCs. For non-binary polar decoding, an SCL decoding based on LLRs is proposed for NBPCs, which can be implemented with non-binary kernels of arbitrary size. Moreover, we propose a Perfect Polarization-Based SCL (PPB-SCL) algorithm based on LLRs to reduce decoding complexity by deriving a new update function of path metric for NBPCs and eliminating the path splitting process at perfect polarized (i.e., highly reliable) positions. Simulation results show that the bit error rate of the proposed NBPCs significantly outperforms that of BPCs. In addition, the proposed PPB-SCL decoding obtains about a 40% complexity reduction of SCL decoding for NBPCs.

关键词： Non-binary polar code Log-likelihood ratio Successive-cancellation list Perfect polarization based-SCL Decoding complexity

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Occupational injuries and burn out among orthopedic oncology surgeons

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World Journal of Orthopedics 2022年第12期13卷 1056-1063页

作者： Abdulrahman M Alaseem robert e Turcotte Nathalie Ste-Marie Mohammad M Alzahrani Saad M Alqahtani Krista A Goulding Department of Orthopedic Surgery College of MedicineKing Saud UniversityRiyadh 12372Saudi Arabia Department of Orthopedic Surgery McGill University Health CentreMontreal H4A3J1Canada Department of Orthopedic Surgery College of MedicineImam Abdulrahman Bin Faisal universityDammam 34212Saudi Arabia Department of Orthopaedic Surgery Mayo ClinicPhoenixArizona 85054USA

BACKGROUND Orthopedic oncology surgeons commonly engage in prolonged and complex surgical *** types of surgeries increase the risk of physical and psychological stressors,which may in turn make these physicians prone to workrelated occupational *** The aim of this study was to explore in orthopedic oncologists,the prevalence of work-related physical injuries and psychological *** A modified version of the physical discomfort survey was developed to assess occupational injuries among orthopedic oncology surgeon members of the Musculoskeletal Tumor Society,the Canadian Orthopedic Oncology Society and european Musculoskeletal Oncology *** survey was sent by email,and it explored musculoskeletal complaints,psychological disturbances,treatment required for these complaints and the requirement of time off *** A total of 67 surgeon responses were collected.A high number of orthopedic oncologists(84%)reported an occupational *** back pain(39%)was the most prevalent musculoskeletal condition,followed by lumbar disk herniation(16%),shoulder tendinitis(15%)and lateral epicondylitis(13%).Of the cohort,46%required surgery and 31%required time off work due to their ***-three respondents reported a psychological ***(27%),anxiety(20%)and insomnia(20%)were the most commonly *** required off work due to injury was associated with old age and years in *** Orthopedic oncology surgeons report a high prevalence of work-related *** back related injury and burnout were the most reported *** operative room ergonomics and prevention of stress related to the work environment should be areas to explore in upcoming research.

关键词： Orthopedic oncology Surgeons Occupational Musculoskeletal Injuries

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Hypoxic training methods for improving endurance exercise performance

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Journal of Sport and Health Science 2015年第4期4卷 325-332页

作者： Jacob A. Sinex robert e Chapman School of Public Health Department of Kinesiology Human Performance Laboratory Indiana University Bloomington IN 47401 USA

耐力运动表现与很多因素都高度相关,这些因素可以通过高原训练和低氧训练改变,包括增加红细胞量、提高最大有氧运动能力、增加毛细血管密度和提高有氧运动的经济性。针对短期和长期暴露在低氧环境中的生理适应性已有很多研究,发现从短... 详细信息

耐力运动表现与很多因素都高度相关,这些因素可以通过高原训练和低氧训练改变,包括增加红细胞量、提高最大有氧运动能力、增加毛细血管密度和提高有氧运动的经济性。针对短期和长期暴露在低氧环境中的生理适应性已有很多研究,发现从短期的不利影响到长期适应的过程可提高在高原和海平面比赛的运动表现。许多高原和低氧训练方案逐步被改良,包括通过在海平面、低、中、高不同海拔,以及自然或人工的海拔中生活和训练的各种组合,产生不同程度的训练效果。部分因素已被证实与低氧训练的个体反应有关,鉴定这些运动员最有可能受益于低氧训练的技术值得进一步研究。本研究建议的高住低练方案为;低海拔地区训练的同时,在足够的高度(2 000-3 000 m)每天至少生活12 h,周期最少为21天。尽管此类高住低练建议普遍存在.但有关高原训练时间和比赛运动表现的关系仍存在争论。

关键词：训练方法低氧运动成绩耐力缺氧环境低海拔地区运动表现细胞体积

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