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Journal of Environmental Sciences 2012年第5期24卷 790-799页

作者： Huub J. M. op den camp Department of Microbiology IWWR Radboud University Nijmegen

The spatial distribution and diversity of archaeal and bacterial ammonia oxidizers （AOA and AOB） were evaluated targeting amoA genes in the gradient of a littoral buffer zone which has been identified as a hot spot for N cycling. Here we found high spatial heterogeneity in the nitrification rate and abundance of ammonia oxidizers in the five sampling sites. The bacterial amoA gene was numerically dominant in most of the surface soil but decreased dramatically in deep layers. Higher nitrification potentials were detected in two sites near the land/water interface at 4.4–6.1 μg NO2-N/（g dry weight soil·hr）, while only 1.0–1.7 μg NO2-N/（g dry weight soil·hr） was measured at other sites. The potential nitrification rates were proportional to the amoA gene abundance for AOB, but with no significant correlation with AOA. The NH4＋ concentration was the most determinative parameter for the abundance of AOB and potential nitrification rates in this study. Higher richness in the surface layer was found in the analysis of biodiversity. Phylogenetic analysis revealed that most of the bacterial amoA sequences in surface soil were affiliated with the genus of Nitrosopira while the archaeal sequences were almost equally affiliated with candidatus ‘Nitrososphaera gargensis’ and candidatus ‘Nitrosocaldus yellowstonii’. The spatial distribution of AOA and AOB indicated that bacteria may play a more important role in nitrification in the littoral buffer zone of a N-rich lake.

关键词： littoral zone ammonia oxidation archaea bacteria heterogeneity abundance

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分度温度灯时对重复测量的研究

国外计量 1981年第5期 30-31页

作者： c.Б.opлов 孙鼎文

按照文献[1],对测量900～2000℃范围亮度温度的СИ-10-300型二等标准温度灯,应每隔100℃在12个点上进行分度。在每一点上,给标准灯以电流,使标准灯与被分度灯的亮度平衡,并测量被分度灯的电流。同时,不管上述测量结果如何,应接着再进... 详细信息

按照文献[1],对测量900～2000℃范围亮度温度的СИ-10-300型二等标准温度灯,应每隔100℃在12个点上进行分度。在每一点上,给标准灯以电流,使标准灯与被分度灯的亮度平衡,并测量被分度灯的电流。同时,不管上述测量结果如何,应接着再进行随后的测量。不过,对于确定温度灯的特性来说,以后的每一次测量的作用,随着测量次数的增加而减小。

关键词：温度灯分度亮度温度

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俄罗斯的固体矿产勘查工作

国土资源情报 2004年第7期 23-26,34页

作者： K.M.Бopиc 李青山俄自然资源部矿物原料资源局

俄罗斯的固体矿产矿物原料综合体带着一系列严重的问题走进21世纪,这些问题多数是因为在苏联时期形成的矿物原料基地在目前开放的市场条件下,都有必要进行实际评估.如果不算在90年代初期无偿交给私人采矿企业的那些好矿床,那么就一系列... 详细信息

俄罗斯的固体矿产矿物原料综合体带着一系列严重的问题走进21世纪,这些问题多数是因为在苏联时期形成的矿物原料基地在目前开放的市场条件下,都有必要进行实际评估.如果不算在90年代初期无偿交给私人采矿企业的那些好矿床,那么就一系列矿产来说,许多未分配的地下资源探明矿床开发的地质经济指标与国外同类矿床相比远为不利.一些矿种的竞争力差,还有一些加工企业和曾经向俄罗斯工业提供原料的许多矿床位于独联体其他国家境内,因而形成这样的情况,即俄罗斯采矿冶金综合体在一定程度上依靠国外提供矿物原料(锰、铬矿石、钛、锆石、铝土矿等).此外,国内形成的新经济关系体制造成的情况是,当采矿公司和支持它的银行机构做出投资开发偿还期较长的国内矿床的决策时,由于政治原因而被搁置一定的时间.

关键词：固体矿产地质勘查矿物原料基地俄罗斯

coating behavior and surface hardening of Pd_(77)cu_6Si_(17) thin film metallic glass on AZ31 magnesium alloy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第12期14卷 898-905页

作者： X.H.DU Y.c.cHANG H.J.PEI B.Y.cHEN M.c.KUO J.c.HUANG School of Materials Sciences and Engineering Shenyang Aerospace University Department of Materials and optoelectronic Science National Sun Yat-Sen University Department of Materials Engineering Kun Shan University

Pd77cu6Si17(PcS) thin film metallic glasses(TFMGs) with high glass forming ability and hardness were selected as a hard coating for improving the surface hardness of AZ31 magnesium alloy. Both microindentation and nanoindentation tests were conducted on specimens with various PcS film thicknesses from 30 to 2000 nm. The apparent hardness and the relative indentation depth(β) were integrated using a quantitative model. The interaction parameters involved and relative hardness values were extracted from iterative calculations. According to the results, surface hardness can be enhanced greatly by PcS TFMGs in the shallow region, followed by gradual decrease with increasing β ratio. In addition, specimens with thinner coatings(e.g., 200nm) showed greater substrate-film interaction and those with thick coatings(e.g., 2000nm) became prone to film cracking. The optimum TFMG coating thickness in this study was estimated to be around 200 nm.

关键词： Thin film metallic glass(TFMG) Magnesium alloy Sputtering process Nanoindentation coating thickness

卒中或短暂性脑缺血发作后住院和门诊的护理质量:对荷兰卒中调查的认识

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世界核心医学期刊文摘(神经病学分册) 2006年第12期 48-49页

作者： op Reimer W.J.M.S. Dippel D.W.J. Franke c.L. 郭俊 Dr.Erasmus Mc Department of CardiologyPO Box 20403000 CA RotterdamNetherlands

BAcKGROUND AND PURPOSE-Limited data are available on management of outpatients with stroke or transient ischemic attack(TIA)and on clinicians'reasons for withholding procedures recommended by *** assessed to what extent guidelines are appropriately applied after ischemic stroke or TIA,in admitted patients as well as ***-A survey was conducted in 11 centers in the Netherlands,which prospectively enrolled 579 admitted patients and 393 *** were collected by trained research *** assessment in 10%of patients showed good agreement with neurologists(median κ=0.86).Treating neurologists were asked to provide arguments for withholding recommended procedures in eligible ***-Recommended acute procedures were provided in the majority of admitted patients,but less often in outpatients:brain imaging(98%and 93%,respectively),12-lead EcG(96%and 81%),laboratory tests(97%and 86%),aspirin within 48 hours(90%and 68%of eligible patients).Secondary preventive measures were not always taken in both eligible inpatients and eligible outpatients:carotid endarterectomy(provided in 31%and 30%of patients),antiplatelet agents(93%and 90%),oral anticoagulants(60%and 48%),antihypertensive agents(57%and 44%),and cholesterol-lowering therapy(71%and 52%).Reasons for withholding recommended procedures were plausible for almost all admitted patients,but were unclear in the majority of ***-compared with other national stroke surveys,we found high-quality acute care in admitted ischemic stroke patients,whereas secondary prevention was comparably *** the majority of our centers have rapid-access TIA clinics,there is still substantial potential to improve quality of stroke care in outpatients.

关键词：卒中 TIA 中风短暂性脑缺血暂时性脑缺血护理质量荷兰

Invasion genetics： Lessons from a ubiquitous bird, the house sparrow Passer domesticus

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current Zoology 2015年第3期61卷 465-476页

作者： Andrea L. LIEBL Aaron W. ScHREY Samuel c. ANDREW Elizabeth L.SHELDON Simon c. GRIFFITH University of Exeter ComwaU Campus Penryn Cornwall TR10 9EZ UK Department of Biology Armstrong State University Savannah GA31419 USA Department of Biological Sciences Macquarie University Sydney NSW 2109 Australia

Following an introduction, non-native species are exposed to environments that differ from those found in their native range; further, as these non-native species expand beyond the site of introduction, they must constantly adapt to novel environ- ments. Although introduced species are present across most ecosystems, few species have successfully established themselves on a truly global scale. One such species, the house sparrow Passer domesticus, is now one of the world＇s most broadly distributed vertebrate species and has been introduced to a great part of its current range. To date, work on four continents suggests both ge- netic and phenotypic variation exists between native and introduced ranges. As such, house sparrows represent an excellent op- portunity to study adaptations to novel environments and how these adaptations are derived. The global distribution of this spe- cies and the multiple independent introductions to geographically isolated sites allow researchers to ask questions regarding ge- netic variation and adaptation on a global scale. Here, we summarize the molecular studies of invasive house sparrows from the earliest work using allozymes through more recent work on epigenetics; using these studies, we discuss patterns of dispersal of this species. We then discuss future directions in techniques （e.g. next generation sequencing） and how they will provide new in- sight into questions that are fundamental to invasion biology. Finally, we discuss how continued research on the house sparrow in light of these genetic changes and adaptations will elucidate answers of adaptation, invasion biology, range expansion, and resi- lience in vertebrate systems generally

关键词： House sparrow Invasive Passer domesticus

Novel heart valve leaflet designs with stiff polymeric materials and biomimetic kinematics

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Bio-Design and Manufacturing 2024年第6期7卷 1018-1034页

作者： caroline c.Smid Georgios A.Pappas Nikola cesarovic Volkmar Falk Paolo Ermanni Laboratory of composite Materials and Adaptive Structures ETH ZürichLeonhardstrasse 218092 ZürichSwitzerland Translational cardiovascular Technologies ETH ZürichLeopold-Ruzicka-Weg 48093 ZürichSwitzerland Department for cardiothoracic and Vascular Surgery Deutsches Herzzentrum der CharitéCharitéUniversitätsmedizin BerlinAugustenburger Pl.113353 BerlinGermany German center for cardiovascular Research(DZHK) Partner Site BerlinAugustenburger Pl.113353 BerlinGermany

Despite continuous efforts to improve the robustness of cardiac valve implants,neither bioprosthetic nor mechanical valves fulfill both hemodynamic and durability *** study discussed novel flexible leaflet designs,focusing on polymeric materials with proven hemocompatibility,such as polyether ether ketone,of much higher stiffness than native tissue,aiming at optimal valve implants.A biomimetic valve with a single-curvature belly-curve(B-c)was used as a reference for new design variants with a double-curvature B-c with varying ***(13.2 MPa)and stiff(2.4 GPa)leaflet materials and different thicknesses were studied using lean simulations and in vitro experiments under physiologic hemodynamic *** performance was assessed using opening pressure(op)and orifice area(OA).The latter was determined by a newly developed automatized image processing *** trends are in agreement with simulations and demonstrated that a buckling-inspired double-curvature leaflet design significantly enhances the trileaflet valve opening behavior,which is particularly advantageous for stiffer leaflet *** to the reference,the best-performing variant showed an op improvement of 47%and 44%based on simulations and experiments,*** contrast,the achieved mean pressure differential was directly comparable to state-of-the-art bioprosthetic *** OA was slightly reduced for new variants but still in the satisfying range.

关键词： Fully polymeric heart valve Parametric leaflet design Finite element analysis Leaflet kinematics In vitro testing

Intraocular inflammation after Ultrasound cyclo Plasty for the treatment of glaucoma

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International Journal of ophthalmology(English edition) 2019年第2期12卷 338-341页

作者： Marco Pellegrini Stefano Sebastiani Giuseppe Giannaccare Emilio c.campos ophthalmology Unit S.Orsola-Malpighi University Hospital DIMES University of Bologna

This is a prospective interventional clinical study evaluating intraocular inflammation developed after Ultrasound cyclo Plasty(UcP) for the treatment of glaucoma. Eighteen eyes of 18 patients were treated with UcP second-generation probes(Eye op1). After treatment, the mean intraocular pressure(Iop) significantly decreased from 26.8±7.2 to 18.8±6.1 mm Hg at day 1 and to 14.7±3.4 mm Hg at month 6(all Pcell photometry value steeply increased after surgery from 12.1±7.5 to 64.1±53.9 ph/ms(P=0.001) at day 1, and then progressively decreased to respectively 60.6±49.7 at day 7, 43.5±38.5 at day 14 and 28.2±18.3 at month 1(all Pctively 16.7±6.2 and 12.8±10.2, both P>0.05). A significant negative correlation was found between postoperative increase of aqueous flare values and anterior chamber depth(R=-0.568, P=0.014). This timeframe may be considered reasonable for repeating UcP treatment, when required.

关键词： Ultrasound cyclo Plasty glaucoma intraocular pressure ciliary body intraocular inflammation laser flare-cell photometry

Description of trauma among French service members in the Department of Defense Trauma Registry: Understanding the nature of trauma and the care provided

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Military Medical Research 2019年第4期6卷 275-283页

作者： Marc A.Schweizer Jud c.Janak Zsolt T.Stockinger Tristan Monchal United States Department of Defense Joint Trauma System Joint Base San Antonio Fort Sam HoustonHoustonTX 78234USA Naval Medical Readiness Training command Jacksonville JacksonvilleFL 32212USA Sainte Anne Military Hospital 600-83800 Toulon Cedex 9BPFrance

Background:Since 2001,the French Armed Forces have sustained many casualties during the Global War on Terror;however,even today,there is no French Military trauma *** French service members(SMs)were treated in US Military Medical Treatment Facilities(MTFs)and were recorded in the US Department of Defense Trauma Registry(Do DTR).Our objective was to conduct a descriptive analysis of the injuries sustained by French SMs reported in the Do DTR and subsequent care provided to them to assist in understanding the importance of building a French Military trauma ***:Using Do DTR data collected from 2001 to 2017,a retrospective descriptive analysis was *** identified 59 French SMs treated in US *** characteristics of the SMs’demographics,injuries,care provided to them,and discharge outcomes were ***:Among the 59 French SMs identified,46(78%)sustained battle injuries(BIs)and 13(22%)sustained nonbattle injuries(NBIs).There were 47(80%)SMs injured in Afghanistan(opération Pamir),while 12(20%)were injured in opération chammal in Iraq and *** accounted for 52.5%of injuries,while 25.4%were due to gunshot wounds;all were *** majority of reported injuries were penetrating(59.3%),most of which were BIs(71.7%).The mean Injury Severity Score for BIs was 12(SD=8.9)compared to 6(SD=1.7)for *** half of SMs(n=30;51%)were injured in Afghanistan between the years 2008–*** a total of 246 injuries sustained by 59 patients,extremities were the body part most prone to BIs followed by the head and *** SMs died after admission(6.8%).conclusions:The Do DTR provides extensive data on trauma injuries that can be used to inform injury prevention and clinical *** majority of injuries sustained by French SMs were BIs,caused by explosives,and predominantly occurring to the extremities;these findings are similar to those of other studies conducted in combat *** is a need to establish a French Military tr

关键词： French service members US military treatment facility Trauma registry

Deployment of wireless sensor network in dispersed renewable energy sources for increasing efficiency of power distribution networks

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Journal of Modern Power Systems and clean Energy 2015年第4期3卷 610-618页

作者： Theodoros A.TSIFTSIS Paschalis c.SOFOTASIOS Nick PAPANIKOLAOU Michael I.LOUPIS Technological Educational Institute(T.E.I.)of central Greece 35100 LamiaGreece Tampere University of Technology 33101 TampereFinland Democritus University of Thrace Kimmeria67100 XanthiGreece

In this work,a novel performance analysis method for evaluating the robustness of emerging power distribution networks(PDNs),which involve deployable renewable energy sources,is *** is realized with the aid of the outage probability(op)criterion in the context of cooperative communications,which is widely considered in modern wireless communication *** main usefulness of this method is that it allows the involved components to communicate to each-other by means of a robust and flexible wireless sensor network *** this context,any conventional medium voltage(MV)bus of the PDN is represented as a wireless relay node where data signals gathered from each MV bus can be forwarded reliably to a control station for the subsequent *** received signals at wireless nodes are decoded and then forwarded to ensure minimal errors and maximal robustness at the receiving *** considered op analysis denotes the probability that the power of a received information signal drops below a pre-defined threshold which satisfies the acceptable Quality of Service requirements of a reliable signal *** this end,simple closed-form expressions are proposed for the op of a regenerative cooperative-based PDN in the presence of various multipath fading effects,which degrade information signals during wireless *** offered results are rather simple and provide meaningful insights for the design and deployment of smart grid systems.

关键词： Smart grid cooperative communications(ccs) Power distribution network(PDN) Outage probability Renewable energy source(RES) Wireless sensor network(WSN)