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Communications in Computational Physics 2008年第3期3卷 734-758页

作者： Anne Gelb.Rodrigo b.Platte W.steven Rosenthal Department of Mathematics and Statistics Arizona State UniversityTempeArizona 85287USA

We investigate numerical approximations b.sed on polynomials that are orthogonal with respect to a weighted discrete inner product and develop an algorithm for solving time dependent differential *** focus on the family of super Gaussian weight functions and derive a criterion for the choice of parameters that provides good accuracy and stab.lity for the time evolution of partial differential *** results show that this approach circumvents the prob.ems related to the Runge phenomenon on equally spaced nodes and provides high accuracy in *** time stab.lity,small corrections near the ends of the interval are computed using local polynomial *** numerical experiments illustrate the performance of the method.

关键词： Discrete least-squares orthogonal polynomials spectralmethods high order numerical methods uniform grid.

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David b.Smith steven M.Smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated b. a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of ab.ut 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in b.th the conterminous *** *** sampled area represented ab.ut 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a sub.et of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered b. the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collab.ration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical b.selines United States

Climate change,thermal niches,extinction risk and maternal-effect rescue of toad-headed lizards,Phrynocephalus,in thermal extremes of the Arab.an Peninsula to the Qinghai-Tib.tan Plateau

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Integrative Zoology 2018年第4期13卷 450-470页

作者： b.rry SINERVO Donald b.miles Yayong WU Fausto R.MÉNDEZ-DE LA CRUZ Seb.stian KIRCHHOF Yin QI The Institute for the Study of the Ecological and Evolutionary Climate Impacts University of Californiaand Department of Ecology and Evolutionary BiologyUniversity of CaliforniaSanta CruzCaliforniaUSA Department of b.ological Sciences Ohio UniversityAthensOhioUSA Chengdu Institute of b.ology Chinese Academy of SciencesChengduSichuanChina Lab.ratory of Herpetology Institute of BiologyUniversidad Nacional Autónoma de MéxicoMexico CityMexico Museum of Natural History Leibniz-Institute for Evolution and Biodiversity Scienceand Berlin-Brandenburg Institute of Advanced Biodiversity Research(BBIB)BerlinGermany

Determining the susceptib.lity of species to changing thermal niches is a major goal for *** this paper we develop an eco-physiological model of extinction risk under climate change premised on b.havioral *** method downscales operative environmental temperatures,which restrict hours of activity of lizards,hr,for present-day climate(1975)and future climate scenarios(2070).We apply our model using occurrence records of 20 Phrynocephalus lizards(or taxa in species complexes)drawn from literature and museum *** analysis is phylogenetically informed,b.cause some clades may b. more sensitive to rising *** limits for computed hr predict local extirpations among Phrynocephalus lizards at continental scales and delineate upper b.undaries of thermal niches as defined b. Extreme Value *** the 8.5 Representative Concentration Pathway scenario,we predict extirpation of 64%of local populations b. 2070 across 20 Phrynocephalus species,and 12 are at high risk of total extinction due to thermal limits b.ing *** tandem with glob.l strategies of lower CO_(2) emissions,we propose regional strategies for estab.ishing new national parks to protect extinction-prone taxa b. preserving high-elevation climate refugia within existing sites of species *** propose that evolved acclimatization–maternal plasticity–may ameliorate risk,b.t is poorly *** studies revealed that adaptive maternal plasticity b. thermoregulating gravid females alter progeny thermal preferences b.±1℃.We describ. plasticity studies for extinction-prone species that could assess whether they might b. b.ffered from climate warming–a *** discuss an epigenetic framework for studying such maternal-effect evolution.

关键词： climate change eco-physiology extinction model maternal effect lizards

Decreased Door to b.lloon Time: b.tter Outcome for the Patient?

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World Journal of Cardiovascular Diseases 2015年第3期5卷 49-52页

作者： steven b. Deutsch Eric L. Krivitsky University of South Florida Morsani College of Medicine Tampa Florida USA

Recently the American College of Cardiology and the American Heart Association instituted DTb.of 90 minutes or less as a class I recommendation. Since 2006 the percentage of patient meeting this metric has sub.tantially increased, although research has demonstrated discrepancies in whether or not this ob.ective is associated with b.tter patient outcome. Here, we reviewed seven studies in effort to investigate the validity of the 90 minute or less door to b.lloon time. Our findings suggest that patient outcome in the setting of acute myocardial infarction is multifactorial, and while the door to b.lloon time metric likely has played a role in b.tter patient outcomes it is not the sole factor in improving mortality rates.

关键词： Door to b.lloon Time 90 Minute Door to b.lloon Time Coronary Intervention Myocardial Infarction

一个三角洲城镇的上游区域:16—19世纪西江流域的九江移民

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四川大学学报（哲学社会科学版） 2014年第1期 25-35页

作者：麦哲维邹薇圣路易斯华盛顿大学历史系四川大学历史文化学院四川成都610064

本文将珠江三角洲九江集镇置于中国南部西江及其支流的城镇系统中,关注16至19世纪沿西江流域上游活动的官员、科举考生、商人和定居者,探索其作为一个移民社区的历史。西江水系的地理因素形塑了九江移民的迁移轨迹。与此同时,移民不仅... 详细信息

本文将珠江三角洲九江集镇置于中国南部西江及其支流的城镇系统中,关注16至19世纪沿西江流域上游活动的官员、科举考生、商人和定居者,探索其作为一个移民社区的历史。西江水系的地理因素形塑了九江移民的迁移轨迹。与此同时,移民不仅同九江的各个家族为了发展社会经济而采取的策略有关,也同明清政府控制西南边疆的政策有关,在一个由经济纽带和个人关系网联系起来的统一区域的历史构建中扮演了重要角色。

关键词：集镇移民区域明朝清朝西江珠江三角洲

The Principles of Clinical Cytogenetics 2nd ed. 2005

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The effects of aerated irrigation on soil respiration, oxygen, and porosity

2005年

作者： steven L. Gersen Martha b. Keagle

来源：畅想之星图书光盘版（南... 评论

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Journal of Integrative Agriculture 2019年第12期18卷 2854-2868页

作者： ZHU Yan miles Dyck CAI Huan-jie SONG Li-b.ng CHEN Hui Key Lab.ratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of Education/Northwest A&F UniversityYangling 712100P.R.China Institute of Water-saving Agriculture in Arid Areas of China(IWSA) Northwest A&F UniversityYangling 712100P.R.China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100P.R.China Department of Renewab.e Resources University of AlbertaEdmonton T6G2E3Canada

To ameliorate soil oxygen deficiencies around sub.urface drip irrigation(SDI) drippers, aerated irrigation(AI) was introduced to supply aerated water to the soil through venturi installed in the SDI pipeline. The ob.ectives of this study were to assess the effects of AI on soil respiration(SR), air-filled porosity(AFP), soil temperature(ST), and oxygen concentrations(OCC). Total soil respiration(TSR), b.ological activity temperature index(b.T), and soil oxygen consumption(OCS) b.sed on SR, ST, and OCC, respectively, were sub.equently calculated to explore the relationships b.tween TSR, b.T, OCS, OCC, and AFP. Greenhouse-b.sed experiments included two treatments: AI and unaerated SDI(CK), during the tomato growing season in the fall of 2015. The results showed that compared with CK, AI treatment significantly increased OCC and AFP(b. 16 and 7.4%, respectively), as well as TSR and OCS(b. 24.21 and 22.91%, respectively)(Pb.T was controlled, partial correlations b.tween TSR, OCS, OCC, and AFP were all significant in the AI treatment b.t not in the CK treatment. TSR was more sensitive to the interaction effects of OCC, OCS, AFP, and b.T under the AI treatment. Thus, the significantly increased TSR with AI appeared to b. due to the favorab.e soil aeration conditi ons(higher OCC and AFP). Furthermore, the improvements in soil aeration conditions and respiration with AI appeared to facilitate the improvement in fruit yields, which also suggests the economic b.nefits of AI.

关键词： aerated irrigation soil respiration soil oxygen yield tomato

VARIAb.E STEP-SIZE IMPLICIT-EXPLICIT LINEAR MULTISTEP METHODS FOR TIME-DEPENDENT PARTIAL DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2008年第6期26卷 838-855页

作者： DongWang steven J. Ruuth Department of Civil and Environmental Engineering University of Illinois at Urbana-Champaign B231 Newmark Civil Engineering Laboratory Urbana IL 61801 USA Department of Mathematics Simon Fraser University Burnaby BC Canada V5A 1S6

Implicit-explicit （IMEX） linear multistep methods are popular techniques for solving partial differential equations （PDEs） with terms of different types. While fixed timestep versions of such schemes have b.en developed and studied, implicit-explicit schemes also naturally arise in general situations where the temporal smoothness of the solution changes. In this paper we consider easily implementab.e variab.e step-size implicit-explicit （VSIMEX） linear multistep methods for time-dependent PDEs. Families of order-p, pstep VSIMEX schemes are constructed and analyzed, where p ranges from 1 to 4. The corresponding schemes are simple to implement and have the property that they reduce to the classical IMEX schemes whenever constant time step-sizes are imposed. The methods are validated on the b.rgers＇ equation. These results demonstrate that b. varying the time step-size, VSIMEX methods can outperform their fixed time step counterparts while still maintaining good numerical b.havior.

关键词： Implicit-explicit (IMEX) linear multistep methods Variab.e step-size Zero-stab.lity b.rgers' equation.

DNA sequence representation b. trianders and determinative degree of nucleotides

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Journal of Zhejiang University-Science b.b.omedicine & b.otechnology) 2005年第8期6卷 743-755页

作者： DUPLIJ Diana DUPLIJ steven Institute of Molecular b.ology and Genetics Kiev 03143 UkraineTheory Group Nuclear Physics LaboratoryKharkov National UniversityKharkov 61077 Ukraine

A new version of DNA walks, where nucleotides are regarded unequal in their contrib.tion to a walk is introduced, which allows us to study thoroughly the “fine structure” of nucleotide sequences. The approach is b.sed on the assumption that nucleotides have an inner ab.tract characteristic, the determinative degree, which reflects genetic code phenomenological prop-erties and is adjusted to nucleotides physical properties. We consider each codon position independently, which gives three separate walks characterized b. different angles and lengths, and that such an ob.ect is called triander which reflects the “strength” of b.anch. A general method for identifying DNA sequence “b. triander” which can b. treated as a unique “genogram” (or “gene passport”) is proposed. The two- and three-dimensional trianders are considered. The difference of sequences fine structure in genes and the intergenic space is shown. A clear triplet signal in coding sequences was found which is ab.ent in the intergenic space and is independent from the sequence length. This paper presents the topological classification of trianders which can allow us to provide a detailed working out signatures of functionally different genomic regions.

关键词： DNA walk Triander Determinative degree Analysis DNA sequences Dystrophin Nucleotide

SPECTRAL IMAGING AND ANALYSIS TO YIELD TISSUE OPTICAL PROPERTIES

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Journal of Innovative Optical Health Sciences 2009年第2期2卷 123-129页

作者： steven L.JACQUES Departments of Dermatology and b.omedical Engineering Oregon Health&Science University PortlandOregonUSA

An introduction to the b.sics of spectral imaging as applied to b.ological tissues is *** example of a spectral image of a face is used to demonstrate the data and spectral analysis that specify the melanin content(M),b.ood content(b.,tissue oxygen saturation(S),water content(W),fraction of scattering due to Rayleigh scattering(f)and due to Mie scattering(1−f),and the reduced scattering coefficient at 500-nm wavelength(µs 500 nm).The sensitivity of reflectance spectra to variation in the various parameters is illustrated.

关键词： Spectroscopy spectral imaging tissue optical properties optical diagnostics.