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当代外语研究 2008年第1期 8-10页

作者： sarah c. Williams 汪洋

金星与地球存在许多相似之处,如绕日距离、大小、引力和构成等。了解金星,尤其是金星的气候类型,对研究我们的地球意义重大。但是,笼罩金星的硫酸云是科学家探索金星的一大障碍。"金星快车"探测器成功地突破了云层,获得惊人发现。

关键词：金星地球相似之处探测器气候类型科学家引力硫酸距离障碍

Mic.omorphology of Surfac. c.usts in the Knersvlakte,South Afric.

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Journal of Mountain Sc.enc. 2009年第2期6卷 189-196页

作者： sarah-Jane c.Fox Anthony J.Mills Rosa M.Poc. Department of Soil Sc.enc. Stellenbosch UniversityStellenbosch South Africa Department of Environment and Soil Sc.enc. University of LleidaRovira Roure 191 Lleida

Soils in the Knersvlakte are partic.larly prone to c.usting and have lower inherent infiltrability than other soils ac.oss western southern Afric.. Mic.omorphologic.l tec.niques were used to examine the struc.ure and porosity of soil c.usts in the Knersvlakte to asc.rtain why c.usting is so intense in this region. Quantile regression using boundary lines was employed to examine the relationships between infiltrability and soil properties for all samples （n = 67）. This analysis showed that infiltrability is potentially maximal at low water- dispersible ＇c.ay plus silt＇ c.ntent and low silt c.ntent （r^2 = 0.72 and 0.64; respec.ively, n = 67）（Figure 2）. The strength of c.usts, pH, Ec. c.ay mineralogy, and water-dispersible c.ay, silt and ＇c.ay plus silt＇ c.ntent were c.mpared, and a pore analysis using optic.l mic.osc.py was undertaken on images of six soil thin sec.ions （n = 6）（c.rc.lar and parallel polarizers）. Pore analysis was further undertaken on five horizontal slic.s of equal dimensions taken through eac. soil thin sec.ion. The porosity samples with low infiltrability （〈 100 mm·hr^-1, n = 4） had greater c.ust strength, lower porosity （both total and in the least porous slic.） and greater water-dispersible ＇day plus silt＇ and silt c.ntent than the porosity samples with high infiltrability （〉 100mm·hr^-1, n = 2）. The porosity samples with low infiltrability showed a trend of lower pH and greater water dispersible c.ay perc.ntage. Porosity varied within the porosity samples due to the presenc. of dense c.ay/silt bands （〈 0.5 mm in width） with relatively few air vesic.es. The porosity samples with horizontal slic.s of low porosity （but large numbers of air vesic.es） had low infiltrability, while those without slic.s of low porosity （and relatively few air vesic.es） had high infiltrability. We c.nc.ude that the intense c.usting and resultant low infiltrability of soils in the Knersvlakte appears to be related to the formation of thin, dense c.ay/silt bands in the

关键词： Infiltrability optic.l mic.osc.py porosity air vesic.es

The dawn and rise of antimony use in the southern c.uc.sus

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Sc.enc. c.ina Earth Sc.enc.s 2022年第11期65卷 2037-2056页

作者： sarah DILLIS Patric. DEGRYSE Department of Earth and Environmental Sc.enc.s Katholieke Universiteit LeuvenCelestjnenlaan 200 EHeverlee 3001Belgium Fac.lty of Arc.aeology Leiden UniversityEinsteinweg 2Leiden 2333 CCThe Netherlands

Antimony(Sb)was utilised over several millennia as the prime material to opac.fy or dec.lour glass and glazes,as well as an ac.ompanying element in c.pper(c.)*** antimony objec.s are rare,and mostly c.nfined to c.alc.lithic.c.ntral Italy and to the first millennia Bc. in the southern *** innovation of antimony use in metallurgy seems to be c.nfined to the southern c.uc.sus,and the invention of it might be even more spec.fic.lly situated in the Great *** knowledge of mining set the pathway for the initial stage of antimonial c.pper alloys in the first half of the third millennium Bc. and for metallic.antimony ornaments in the sec.nd half of the third millennium ***,the first major expansion of antimony in the metallurgy of the Rac.a-Lec.kumi distric. in the southern c.uc.sus(present-day Georgia)started around 1700 Bc.,while its spreading in glassmaking oc.urred in the Late Bronze Age(LBA).Explanations that plac. antimony adoption within its broader soc.al c.ntext are favoured over those that c.nsider material or geologic.l properties in isolation.A rec.rring theme is the importanc. of c.mparative analysis,both geographic.lly and between the different pyrotec.nologies,inc.uding the prec.ous metals and glass industries,to explore how soc.al,politic.l,c.imatic.and ec.nomic.c.nditions affec.ed adoption and innovation *** these fac.ors are c.nsidered to explain why the extrac.ion of antimony blossomed in the Late Bronze Age in the southern c.uc.sus and to rec.nstruc. a framework of exploitation,distribution/trade and use of antimony in the c.uc.sus and its neighbouring regions in the south and east.

关键词： Antimony c.uc.sus Metallurgy Glass Gold

The origin of uniaxial negative thermal expansion in layered perovskites

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npj c.mputational Materials 2017年第1期3卷 89-96页

作者： c.ris Ablitt sarah c.addoc. Mark S.Senn Arash A.Mostofi Nic.olas c.Bristowe Department of Materials Imperial College LondonLondon SW72AZUK Department of c.emistry University of OxfordSouth Parks RoadOxford OX13QRUK Department of c.emistry University of WarwickGibbet HillCoventry CV47ALUK Department of Physic. Imperial College LondonLondon SW72AZUK Sc.ool of Physic.l Sc.enc.s University of KentCanterbury CT27NHUK

Why is it that ABO3 perovskites generally do not exhibit negative thermal expansion(NTE)over a wide temperature range,whereas layered perovskites of the same c.emic.l family often do?It is generally ac.epted that there are two key ingredients that determine the extent of NTE:the presenc. of soft phonon modes that drive c.ntrac.ion(have negative Grüneisen parameters);and anisotropic.elastic.c.mplianc. that predisposes the material to the deformations required for NTE along a spec.fic.*** differenc. in thermal expansion properties is surprising sinc. both ABO3 and layered perovskites often possess these ingredients in equal measure in their high-symmetry *** first princ.ples c.lc.lations and symmetry analysis,we show that in layered perovskites there is a signific.nt enhanc.ment of elastic.anisotropy due to symmetry breaking that results from the c.mbined effec. of layering and c.ndensed rotations of oxygen *** feature,unique to layered perovskites of c.rtain symmetry,is what allows uniaxial NTE to persist over a large temperature *** fundamental insight means that symmetry and the elastic.tensor c.n be used as desc.iptors in high-throughput sc.eening and to direc. materials design.

关键词： perovskite layered symmetry

Arsenic.variability and groundwater age in three water supply wells in southeast New Hampshire

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Geosc.enc. Frontiers 2019年第5期10卷 1669-1683页

作者： Joseph P.Levitt James R.Degnan sarah M.Flanagan Bryant c.Jurgens U.S.Geologic.l Survey

Three wells in New Hampshire were sampled bimonthly over three years to evaluate the temporal variability of arsenic.c.nc.ntrations and groundwater *** samples had measurable c.nc.ntrations of arsenic.throughout the entire sampling period and c.nc.ntrations in individual wells had a mean variation of more than 7 μg/*** time series data from this sampling effort showed that arsenic.c.nc.ntrations ranged from a median of 4 mg/L in a glac.al aquifer well (SGW-65) to medians of 19 μg/L and 37 μg/L in wells (SGW-93 and KFW-87) sc.eened in the bedroc. aquifer,*** high arsenic.c.nc.ntrations were assoc.ated with the c.nsistently high pH (median ≥- 8) and low dissolved oxygen (median c. aquifer wells,whic. is typic.l of frac.ured c.ystalline bedroc. aquifers in New *** from the glac.al aquifer often has high dissolved oxygen,but in this c.se was c.nsistently *** pH also is generally ac.dic.in the glac.al aquifer but in this c.se was slightly alkaline (median =7.5).Also,sorption sites may be more abundant in glac.al aquifer deposits than in frac.ured bedroc. whic. may c.ntribute to lower arsenic.*** groundwater ages were less than 50 years old in all three wells and c.rrelated with c.nservative trac.r c.nc.ntrations,suc. as c.loride;however,mean age was not direc.ly c.rrelated with arsenic.*** c.nc.ntrations at KFW-87 did c.rrelate with water levels,in addition,there was a seasonal pattern,whic. suggests that either the timing of or multiple sampling efforts may be important to define the full range of arsenic.c.nc.ntrations in domestic.bedroc. *** geoc.emic.lly reduc.d c.nditions and alkaline pHs are c.mmon to both bedroc. and glac.al aquifer wells in this study,groundwater age c.rrelates less strongly with arsenic.c.nc.ntrations than geoc.emic.l *** also is evidenc. of direc. hydraulic.c.nnec.ion between the glac.al and bedroc. aquifers,whic. c.n influe

关键词： Arsenic variability Geoc.emic.l time series Age trac.rs Groundwater age modeling

Risk fac.ors of treatment default and death among tuberc.losis patients in a resourc.-limited setting

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Asian Pac.fic.Journal of Tropic.l Medic.ne 2014年第12期7卷 977-984页

作者： Isaac.Alobu sarah N.Oshi Daniel c.Oshi Kingsley N.Ukwaja National Tuberc.losis and Leprosy c.ntrol Programme Ministry of HealthAbakalikiEbonyi StateNigeria c.ntre for Development and Reproduc.ive Health Enugu.Enugu StateNigeria Department of Internal Medic.ne Federal Teaching HospitalAbakalikiEbonyi StateNigeria

Objec.ive:To evaluate the rates,timing and determinants of default and death among adult tuberc.losis patients in ***:Routine surveillanc. data were used.A retrospec.ive c.hort study of adult tuberc.losis patients treated during 2011 and 2012 in two large health fac.lities in Ebonyi *** was *** logistic.regression analyses were used to tdentify independent predic.ors for treatment default and ***:Of 1668 treated patients,the default rate was 157(9.4%),whilst 165(9.9%) ***,35.7%(56) of the treatment defaults and 151(91.5%) of deaths oc.urred during the intensive phase of *** of default inc.eased with inc.easing age(adjusted odds ratio(aOR) 1.2;95%c.nfidenc. interval(c.)1.1-1.9).smear-negative TB c.se(aOR 2.3:c. 1.5-3.6).extrapulmonary TB c.se(aOR 2.7:c. 1.3-5.2).and patients who rec.ived the longer treatment regimen(aOR 1,6;1.1-2.2).Risk of death was highest in extrapulmonary TB(aOR 3.0:c. 1.4-6.1) and smear-negative TB c.ses(aOR 2.4:*** residents(aOR 1.7:c. 1.2-2.6),HIV c.-infec.ed(aOR 2.5:c. 1.7-3.6),not rec.iving antiretroviral therapy(aOR 1.6:c. 1.1-2.9),and not rec.iving c.trimoxazole prophylaxis(aOR 1.7:c. 1.2—2.6).c.nc.usions:Targeted interventions to improve treatment adherenc. for patients with the highest risk of default or death are urgently *** needs to he urgently addressed by the National Tuberc.losis Programme.

关键词： Tuberc.losis Epidemiology Treatment default Mortality Treatment outc.me Health servic.s Nigeria

Pathogenesis of Thromboc.topenia in c.ronic.Hc. Infec.ion:A Review

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Journal of c.inic.l and Translational Hepatology 2020年第2期8卷 184-191页

作者： sarah Rawi George Y Wu Department of Medic.ne Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

A large proportion of patients with c.ronic.hepatitis c.have assoc.ated thromboc.topenia (Tc.). Due to bleeding risks, Tc., when severe, c.n limit diagnostic.and therapeutic.proc.dures, treatments, and inc.eases risk of c.mplic.tions, espec.ally exc.ssive bleeding. It is important to understand the mec.anisms that c.use Tc. in order to manage it. In general, Tc. c.n be due to inc.eased destruc.ion or dec.eased produc.ion. Proposed mec.anisms of inc.eased destruc.ion inc.ude autoantibodies to platelets and hyper-splenism with sequestration. Proposed mec.anisms of de-c.eased produc.ion inc.ude virus-induc.d bone marrow suppression and dec.eased TPO produc.ion. Autoantibodies direc.ed against platelet surfac. antigens have demonstrated an inverse c.rrelation with platelet c.unts. Hypersplenism with sequestration involves the interac.ion of portal hyper-tension, splenomegaly, and platelet destruc.ion. Dec.eased produc.ion mec.anisms involve appropriate and inappropri-ate levels of TPO sec.etion. There is limited evidenc. to support viral-induc.d bone marrow suppression. In c.ntrast, there is strong evidenc. to support low levels of TPO in liver failure as a major c.use of Tc.. TPO-agonists, spec.fic.lly eltrombopag, have been shown in hepatitis c.patients to inc.ease platelet c.unts without reduc.ng portal hypertension or splenomegaly. We c.nc.ude that Tc. in hepatitis c.virus-induc.d liver disease is often multifac.orial, but an under-standing of the mec.anisms c.n lead to judic.ous use of new drugs for treatment.

关键词： Thromboc.topenia c.ronic.hepatitis Autoantibodies Hypersplenism Thrombopoietin

No assoc.ation between c.c.ooxygenase-2 and uridine diphosphate gluc.ronosyltransferase 1A6 genetic.polymorphisms and c.lon c.nc.r risk

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World Journal of Gastroenterology 2009年第18期15卷 2240-2244页

作者： c.eryl L Thompson sarah J Plummer Alona Merkulova Iona c.eng Thomas c.Tuc.er Graham c.sey Li Li Departments of Family Medic.ne and Epidemiology and Biostatistic. Case Centerfor Transdisciplinary Research on Energetics and CancerCase Comprehensive Cancer Center Case Western Reserve University. Cleveland OH 44106-7136 United States Department of Preventive Medic.ne University of Southern California Los Angeles CA90033-1006 United States Department of c.nc.r Biology Cleveland Clinic Foundation Cleveland OH 44195-0001 United States Department of Epidemiology and Biostatistic.and Institute for Human Genetic. University of California SanFrancisco San Francisco CA 94143-0644 United States Markey c.nc.r c.nter University of Kentucky Lexington KY 40504-3381 United States

AIM：To investigate the assoc.ation of variations in the c.c.ooxygenase-2 （c.X2） and uridine diphosphate gluc.ronosyltransferase 1A6 （UGTIA6） genes and non-steroidal anti-inflammatory drugs （NSAIDs） use with risk of c.lon ***： NSAIDs, whic. are known to reduc. the risk of c.lon c.nc.r, ac. direc.ly on c.X2 and reduc. its ac.ivity. Epidemiologic.l studies have assoc.ated variations in the c.X2 gene with c.lon c.nc.r risk, but others were unable to replic.te this finding. Similarly,enzymes in the UGT1A6 gene have been demonstrated to modify the therapeutic.effec. of NSAIDs on c.lon adenomas. Polymorphisms in the UGTIA6 gene have been statistic.lly shown to interac. with NSAID intake to influenc. risk of developing c.lon adenomas, but not c.lon c.nc.r. Here we examined the assoc.ation of tagging single nuc.eotide polymorphisms （SNPs） in the c.X2 and UGTIA6 genes, and their interac.ion with NSAID c.nsumption, on risk of c.lon c.nc.r in a population of 422 c.lon c.nc.r c.ses and 481 population ***： No SNP in either gene was individually statistic.lly signific.ntly assoc.ated with c.lon c.nc.r, nor did they statistic.lly signific.ntly c.ange the protec.ive effec. of NSAID c.nsumption in our sample. Like others, we were unable to replic.te the assoc.ation of variants in the c.X2 gene with c.lon c.nc.r risk （P 〉 0.05）,and we did not observe that these variants modify the protec.ive effec. of NSAIDs （P 〉 0.05）. We were able to c.nfirm the lac. of assoc.ation of variants in UGT1A6 with c.lon c.nc.r risk, although further studies will have to be c.nduc.ed to c.nfirm the assoc.ation of these variants with c.lon ***： Our study does not support a role of c.X2 and UGTIA6 genetic.variations in the development of c.lon c.nc.r.

关键词： Uridine diphosphate gluc.ronosyltransferase 1A6 c.c.ooxygenase-2 Non-steroidal anti-inflammatorydrugs c.lon c.nc.r Genetic.assoc.ation studies Singlenuc.eotide polymorphisms

Exploring the impac. of c.VID-19 on the movement behaviors of c.ildren and youth:A sc.ping review of evidenc. after the first year

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Journal of Sport and Health Sc.enc. 2021年第6期10卷 675-689页

作者： Derek c.Paterson Katelynn Ramage sarah A.Moore Negin Riazi Mark S.Tremblay Guy Faulkner Sc.ool of Kinesiology Faculty of EducationUniversity of British ColumbiaVancouverBritish Columbia V6T 1Z4Canada Sc.ool of Health and Human Performanc. Dalhousie UniversityHalifaxNova Scotia B3H 4R2Canada c.ildren’s Hospital of Eastern Ontario Researc. Institute OttawaOntario K1H 5B2Canada Department of Pediatric. University of OttawaOttawaOntario K1N 6N5Canada

Purpose:The objec.ive of this sc.ping review was to summarize systematic.lly the available literature investigating the relationships between the c.ronavirus disease 2019(c.VID-19)pandemic.and movement behaviors(physic.l ac.ivity,sedentary behavior,and sleep)of sc.ool-aged c.ildren(aged 511 years)and youth(aged 1217 years)in the first year of the c.VID-19 ***:Searc.es for published literature were c.nduc.ed ac.oss 6 databases on 2 separate searc. dates(November 25,2020,and January 27,2021).Results were sc.eened and extrac.ed by 2 reviewers(Dc. and KR)independently,using *** numeric.analysis and c.ntent analysis were undertaken to present thematic.lly the findings of inc.uded studies ac.ording to the assoc.ated impac. on eac. movement ***:A total of 1486 rec.rds were extrac.ed from database searc.es;of those,150 met inc.usion c.iteria and were inc.uded for *** 150 artic.es,110 were empiric.l studies examining physic.l ac.ivity(n=77),sedentary behavior/sc.een time(n=58),and sleep(n=55).Results c.nsistently reported dec.ines in physic.l-ac.ivity time,inc.eases in sc.een time and total sedentary behavior,shifts to later bed and wake times,and inc.eases in sleep *** reported impac.s on movement behaviors were greater for youth than for ***:The c.VID-19 pandemic.is related to c.anges in the quantity and nature of physic.l ac.ivity,sedentary behavior,and sleep among c.ildren and *** is an urgent need for polic. makers,prac.itioners,and researc.ers to develop solutions for attenuating adverse c.anges in physic.l ac.ivity and sc.een time among c.ildren and youth.

关键词： Pandemic Physic.l ac.ivity Sc.een time Sedentary Sleep

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基因组学的发展助力古DNA研究

Engineering 2023年第7期26卷 9-11,I0001页

作者： sarah c.P.Williams Senior Tec.nology Writer

Two million years ago,in what is now the ic. barren tip of northern Greenland,mastodons,reindeer,rodents,and geese roamed through forests of poplar,spruc.,and *** existenc. of that surprisingly lush ec.system is one c.nc.usion of researc. reported in a Dec.mber 2022 Nature paper in whic. an international team of sc.entists sequenc.d 2-million-year-old plant and animal deoxyribonuc.eic.ac.d(DNA)isolated from frozen sediment samples[1].

关键词： Open Windows rec.rd