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Impacts of climate gradients on the vegetation phenology of major land use types in Central Asia （1981-2008）

Frontiers of Earth Science 2012年第2期6卷 206-225页

作者： jahan KARIYEVA willem j.d. van leeuwen Connie A. WOOdHOUSE School of Geography and development The University of Arizona Tucson AZ 85721 USA School of Natural Resources and the Environment - Office of Arid Lands Studies - Arizona Remote Sensing Center The University of Arizona Tucson AZ 85721 USA

Time-series of land surface phenology （LSP） data offer insights about vegetation growth patterns. They can be generated by exploiting the temporal and spectral reflectance properties of land surface components. Inter- annual and seasonal LSP data are important for under- standing and predicting an ecosystem＇s response to variations caused by natural and anthropogenic drivers. This research examines spatio-temporal change patterns and interactions between terrestrial phenology and 28 years of climate dynamics in Central Asia. Long-term （1981-2008） LSP records such as timing of the start, peak and length of the growing season and vegetation productivity were derived from remotely sensed vegetation greenness data. The patterns were analyzed to identify and characterize the impact of climate drivers at regional scales. We explored the relationships between phenologi- cal and precipitation and temperature variables for three generalized land use types that were exposed to decade- long regional drought events and intensified land and water resource use： rainfed agriculture, irrigated agriculture, and non-agriculture. To determine whether and how LSP dynamics are associated with climate patterns, a series of simple linear regression analyses between these two variables was executed. The three land use classes showed unique phenological responses to climate variation across Central Asia. Most of the phenological response variables were shown to be positively correlated to precipitation and negatively correlated to temperature. The most substantial climate variable affecting phenological responses of all three land use classes was a spring temperature regime. These results indicate that future higher temperatures would cause earlier and longer growing seasons.

关键词： phenology land use climate variability

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Vegetation productivity responses to drought on tribal lands in the four corners region of the Southwest USA

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Frontiers of Earth Science 2018年第1期12卷 37-51页

作者： Mohamed Abd Salam EL-VILALY Kamel dIdAN Stuart E. MARSH willem j.d. van leeuwen Michael A. CRIMMINS Armando Barreto MUNOZ The Intemational Food Policy Research Institute Washington DC 20006-1002 USA Vegetation Index and Phenology Lab Department of Agricultural and Biosystems Engineering The University of Arizona Tucson AZ 85721-0036 USA Arizona Remote Sensing Center School of Natural Resources and the Environment The University of Arizona Tucson AZ 85721-0043 USA department of Soils Water and Environmental Science The University of Arizona Tucson AZ 85721-0038 USA

For more than a decade, the Four Comers Region has faced extensive and persistent drought conditions that have impacted vegetation communities and local water resources while exacerbating soil erosion. These persistent droughts threaten ecosystem services, agriculture, and livestock activities, and expose the hypersensitivity of this region to inter-annual climate variability and change. Much of the intermountain Western United States has sparse climate and vegetation monitoring stations, making fine-scale drought assessments difficult. Remote sensing data offers the opportunity to assess the impacts of the recent droughts on vegetation productivity across these areas. Here, we propose a drought assessment approach that integrates climate and topographical data with remote sensing vegetation index time series. Multisensor Normalized difference Vegetation Index （NdVI） time series data from 1989 to 2010 at 5.6 km were analyzed to characterize the vegetation productivity changes and responses to the ongoing drought. A multi-linear regression was applied to metrics of vegetation productivity derived from the NdVI time series to detect vegetation productivity, an ecosystem service proxy, and changes. The results show that around 60.13% of the study area is observing a general decline of greenness （p 〈 0.05）, while 3.87% show an unexpected green up, with the remaining areas showing no consistent change. Vegetation in the area show a significant positive correlation with elevation and precipitation gradients. These results, while, confirming the region＇s vegetation decline due to drought, shed further light on the future directions and challenges to the region＇s already stressed ecosystems. Whereas the results provide additional insights into this isolated and vulnerable region, the drought assessment approach used in this study may be adapted for application in other regions where surfacebased climate and vegetation monitoring record is spatially and temporally limited.

关键词： drought remote sensing Hopi Navajo Nation

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High-quality-factor tantalum oxide nanomechanical resonators by laser oxidation of TaSe2

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Nano Research 2015年第9期8卷 2842-2849页

作者： Santiago j. CartamiI-Bueno Peter G. Steeneken Frans d. Tichelaar Efren Navarro-Moratalla Warner j. Venstra Ronald van leeuwen Eugenio Coronado Herre S.j. van der Zant Gary A. Steele Andres Castellanos-Gomez Kavli Institute of Nanoscience Delft University of Technology Lorentzweg 1 2628 CJ Delft The Netherlands Kavli Institute of Nanoscience Delft University of Technology National Centre for HREM Lorentzweg 1 2628 CJ Delft The Netherlands Instituto Ciencia Molecular (ICMol) Univ. Valencia C/Catedrdtico Jos@ Beltrdn 2 E-46980 Paterna Spain

Controlling the strain in two-dimensional （2d） materials is an interesting avenue to tailor the mechanical properties of nanoelectromechanical systems. Here, we demonstrate a technique to fabricate ultrathin tantalum oxide nanomechanical resonators with large stress by the laser oxidation of nano-drumhead resonators composed of tantalum diselenide （TaSe2）, a layered 2d material belonging to the metal dichalcogenides. Before the study of their mechanical properties with a laser interferometer, we verified the oxidation and crystallinity of the freely suspended tantalum oxide using high-resolution electron microscopy. We demonstrate that the stress of tantalum oxide resonators increases by 140 MPa （with respect to pristine TaSe2 resonators）, which causes an enhancement in the quality factor （14 times larger） and resonance frequency （9 times larger） of these resonators.

关键词： TaSe2,tantalum oxide,mechanical resonators,laser oxidation,optical interferometer,high quality factor

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Towards an integrated modeling of the plasma-solid interface

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Frontiers of Chemical Science and Engineering 2019年第2期13卷 201-237页

作者： Michael Bonitz Alexey Filinov jan-willem Abraham Karsten Balzer Hanno Kahlert Eckhard Pehlke Franz X.Bronold Matthias Pamperin Markus Becker dettlef Loffhagen Holger Fehske Institute for Theoretical Physics and Astrophysics Kiel University24098 KielGermany Leibniz Institute for Plasma Research (INP) D-17489 GreifswaldGermany joint Institute for High Temperatures RAS 125412 MoscowRussia Computing Center of Kiel University D-24118 KielGermany Institute of Physics Greifswald UniversityD-17489 GreifswaldGermany

Solids facing a plasma are a common situation in many astrophysical systems and laboratory ***,many plasma technology applications rely on the control of the plasma-surface interaction,i.e.,of the particle,momentum and energy fluxes across the plasma-solid ***,presently often a fundamental understanding of them is missing,so most technological applications are being developed via trial and *** reason is that the physical processes at the interface of a low-temperature plasma and a solid are extremely complex,involving a large number of elementary processes in the plasma,in the solid as well as fluxes across the *** accurate theoretical treatment of these processes is very difficult due to the vastly different system properties on both sides of the interface:Quantum versus classical behavior of electrons in the solid and plasma,respectively;as well as the dramatically differing electron densities,length and time ***,often the system is far from *** the majority of plasma simulations surface processes are either neglected or treated via phenomenological parameters such as sticking coefficients,sputter rates or secondary electron emission ***,those parameters are known only in some cases and with very limited ***,while surface physics simulations have often studied the impact of single ions or neutrals,so far,the influence of a plasma medium and correlations between successive impacts have not been taken into *** an approach,necessarily neglects the mutual influences between plasma and solid surface and cannot have predictive *** this paper we discuss in some detail the physical processes of the plasma-solid interface which brings us to the necessity of coupled plasma-solid *** briefly summarize relevant theoretical methods from solid state and surface physics that are suitable to contribute to such an approach and identify four *** first are

关键词： plasma physics surface science plasmasurface modeling dFT nonequilibrium Green functions

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一个中国人群的免疫球蛋白同种异型的研究

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中华医学遗传学杂志 1986年第1期 1-4页

作者：仲发明 Gerda de Lange jürgenHenke 冯宗忱 Ralph Bernhardt Fred van leeuwen Peter van Eede 同济医科大学微生物学教研室 Central Laboratory of the Netherlands Red Cross Blood Transfusion Service department of Immunogenetics Amsterdam The Netherlands Institute for Forensic Medicine University of düsseldorf. Germany 同济医科大学生物化学教研室 Clinical Institue for Heartinfarct Research Medical University Clinic Heidelberg Germany 同济医科大学微生物学教研室同济医科大学微生物学教研室

血清免疫球蛋白(Ig)同种异型是一种遗传标志,是指同一类、亚类或亚型的Ig分子在同一种系,不同个体间存在差异,这种差异反映了重链或轻链稳定区(或可变区)某一个或几个氨基酸的变异,这种变异构成了不同的遗传标志。

关键词：同种异型人类血清轻链单倍型单元型中国人群亚洲人群

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人肝脏可清除不对称性和对称性二甲基精氨酸

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世界核心医学期刊文摘（胃肠病学分册） 2005年第7期1卷 36-37页

作者： Siroen M.P.C. van der Sijp j.R.M. Teerlink T. P.A.M. van leeuwen 杨瑗 VU University Medical Center Department of Surgery PO Box 7057 1007 MB Amsterdam Netherlands Dr.

Asymmetric (AdMA) and symmetric dimethylarginine (SdMA) inhibit production of nitric oxide. The concentration of both dimethylarginines is regulated by urina ry excretion, although AdMA, but not SdMA, is also subject to degradation by dim ethylarginine dimethylaminohydrolase, which is highly expressed in the liver but also present in the kidney. The exact roles of the human liver and kidney in th e metabolism of dimethylarginines are currently unknown. Therefore, we aimed to investigate renal and hepatic handling of AdMA and SdMA in detail in 24 patients undergoing hepatic surgery. To calculate net organ fluxes and fractional extrac tion (FE) rates, blood was collected from an arterial line, the portal vein, hep atic vein, and renal vein, and blood flow of the hepatic artery, portal vein, an d renal vein was determined using doppler ultrasound techniques. Results showed a significant net uptake (median [IQR]) of AdMA in both the liver (9.6 nmol/min [5.6- 13.2] ) and the kidney (12.1 nmol/min [1.3- 17.1]). SdMA uptake was pres ent not only in the kidney (12.7 nmol/min [3.5- 25.4]), but also in the liver ( 7.7 nmol/min [2.8- 16.4]). FE rates of AdMA for the liver and kidney were 5.0% (3.5% - 7.4% ) and 8.4% (1.3% - 13.9% ), respectively. For SdMA, hepat ic and renal FE rates were 3.4% (2.1% - 7.5% ) and 12.5% (3.6% - 16.2% ), respectively. In conclusion, this study gives a detailed description of the hepatic and renal elimination of dimethylarginines and shows that the clearing o f SdMA is not only confined to the kidney, but the human liver also takes up sub stantial amounts of SdMA from the portal and systemic circulation.

关键词：二甲基精氨酸不对称性尿液排泄肝静脉动脉导管多普勒超声技术肝动脉血液样本血流量肾静脉

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体外循环期间血液稀释和红细胞输注与肾脏和其他内脏损伤生化标记物的相关性

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麻醉与镇痛 2011年第3期7卷 23-31页

作者： Rien A. j. M. Huybregts, Md Roel deVroege, Phd Evert K. jansen, Md AnneW. van Schij.d.l, Md Herman M. T. Christiaans, Md willem van Oeveren Phd 唐建成(译) 刘晓(译) departments of Cardiac Surgery University of Groningen University MedicalCenter Groningen Groningen The Netherlands departments of Anesthesiology University Hospital "Vrije Universiteit"Amsterdam University of Groningen University MedicalCenter Groningen Groningen The Netherlands department of Biomaterials University of Groningen University Medical Center Groningen Groningen The Netherlands 不详

背景体外循环中血液稀释是导致血细胞比容下降的主要原因。血细胞比容降低往往导致血液向组织运氧能力下降，从而需要输注浓缩红细胞。本研究的目的是探讨手术中血细胞比容和输注同种异体血与手术后肾脏和其他脏器损伤标记物的关系。方... 详细信息

背景体外循环中血液稀释是导致血细胞比容下降的主要原因。血细胞比容降低往往导致血液向组织运氧能力下降，从而需要输注浓缩红细胞。本研究的目的是探讨手术中血细胞比容和输注同种异体血与手术后肾脏和其他脏器损伤标记物的关系。方法选择50例连续冠状动脉旁路移植手术的患者作为研究对象，通过测定乳酸水平来评价全身组织缺氧程度。测定尿中N-乙酰-β-d-氨基葡糖苷酶（NAG）和肠脂肪酸结合蛋白（IFABP）的浓度来评估肾脏及其他内脏器官的缺血程度。回顾性地根据体外循环过程中最低血细胞比容的水平将患者分为2组（Hct〈24％或≥24％）进行分析。结果血细胞比容较低组（〈24％）手术中乳酸浓度和手术后NAG和IFABP的浓度均高于血细胞比容较高组（≥24％；P〈0．05）。低血细胞比容分别与高乳酸水平（R^2=0．150，P〈0．01）和高NAG（R^2=0．138，P〈0．01）及IFABP（R^2=0．107，P〈0．0k）浓度相关。体外循环期间输注红细胞与较高乳酸水平（R^2=0．089，P〈0．05）、NAG浓度（R^2=0．431，P〈O．01）及IFABP浓度（R^2=0．189，P〈O．01）相关。结论研究结果表明手术中血液稀释至血细胞比容低于24％和输注红细胞都与肾脏及其他内脏器官损伤标记物相关。

关键词：体外循环期间红细胞输注生化标记物血液稀释内脏损伤肾脏冠状动脉旁路移植手术相关性

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在跌落撞击负载条件下的键合互连可靠性测试(英文)

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电子工业专用设备 2008年第1期37卷 1-9页

作者： j.j.M. Zaal W.d. van driel H.P.Hochstenbachl G.Q.Zhang NXP Semiconductors The NetherlandsThe Netherlands Gerstweg 26534AE Nijmegen The Netherlands delft University of Technology The Netherlands Gerstweg 2 6534AE Nijmegen The Netherlands

在大多数移动通信装置的寿命中最常见的故障是通过跌落撞击产生的。这是当今通过跌落撞击测试的方法测得的,该方法已经通过了j.d.C标准。然而这种方法相当耗时,且复验性方面还存在着一些问题。报道的研究是在与焊凸冷拉相关联的跌落撞... 详细信息

在大多数移动通信装置的寿命中最常见的故障是通过跌落撞击产生的。这是当今通过跌落撞击测试的方法测得的,该方法已经通过了j.d.C标准。然而这种方法相当耗时,且复验性方面还存在着一些问题。报道的研究是在与焊凸冷拉相关联的跌落撞击测试情况下完成的,这两者之间可以替代。本研究方法旨在了解引起故障的机械负载,并不仅仅是适合于数据。因此,跌落撞击测试便成为一种模式并备用来验证这一模式的试验,它将成为未来的处理方式。完成的焊凸冷拉测试研究证实,该测试未将焊凸偏移至一种确定的故障模式,测试研究的结果以及有关焊凸的模拟情况一并作了阐述。两种测试似乎是测试了相同的现象,根据来自CBP(cold bump pull)的结果表明与跌落撞击测试的情况相同,但由于模拟和试验工作尚未完全结束,其中的详情暂无法提供。

关键词：互连可靠性 PCB 跌落撞击测试焊凸冷拉测试

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较大直肠腺瘤中经肛门内镜显微手术与内镜下黏膜切除术的随机对照试验(TRENd研究)

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英国医学杂志中文版 2018年第11期21卷 676-676页

作者： Renee M Barendse Gijsbert d Musters Eelco j R de Graaf Frank j C van den Broek Esther C j Consten Pascal G doornebosch james C Hardwick Ignace H j T de Hingh Chrisiaan Hoft jeroen M jansen A W Marc van Milligen de Wit George P van der Schelling Erik j Schoon Matthijs P Schwartz Bas L A M Weusten Marcel G dijkgraaf Paul Fockens willem A Bemelman Evelien dekker TRENd研究小组李佳宁(译) 吴东(校) 不详北京协和医院消化科

摘要目的非随机研究表明内镜下黏膜切除术(endoscopic mucosal resection,EMR)在切除直肠较大腺瘤时与经肛门内镜显微手术(transanal endoscopic microsurgery,TEM)同样有效,但EMR可能更具成本效益且相对安全。本试验旨在对比摘除较... 详细信息

摘要目的非随机研究表明内镜下黏膜切除术(endoscopic mucosal resection,EMR)在切除直肠较大腺瘤时与经肛门内镜显微手术(transanal endoscopic microsurgery,TEM)同样有效,但EMR可能更具成本效益且相对安全。本试验旨在对比摘除较大直肠腺瘤时EMR与TEM的临床结局与成本效益。

关键词：随机对照试验显微手术切除术内镜黏膜肛门肠腺成本效益

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Efficacy and Safety of Triazavirin Therapy for Coronavirus disease 2019:A Pilot Randomized Controlled Trial

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Engineering 2020年第10期6卷 1339-1347页

作者： Xiaoke Wu Kaijiang Yu Yongchen Wang Wanhai Xu Hongli Ma Yan Hou Yue Li Benzhi Cai Liying Zhu Min Zhang Xiaoli Hu jingshu Gao Yu Wang Huichao Qin Wenjie Wang Mingyan Zhao Xia Wu Yong Zhang Lu Li Kang Li Zhimin du Ben willem j.Mol Baofeng Yang College of Pharmacology Harbin Medical UniversityHarbin 150001China Heilongjiang Provincial Hospital Harbin Institute of TechnologyHarbin 150030China First Affiliated Hospital Heilongjiang University of Chinese MedicineHarbin 150040China First Affiliated Hospital Harbin Medical UniversityHarbin 150001China Second Affiliated Hospital Harbin Medical UniversityHarbin 150001China Fourth Affiliated Hospital Harbin Medical UniversityHarbin 150001China College of Basic Medical Sciences Zhejiang Chinese Medical UniversityHangzhou 310053China Monash Medical Centre.Monash University MelbourneVIC 3800Australia

目前,尚无有效疗法可治愈由严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)引起的新型冠状病毒肺炎(coronavirus disease 2019,COVId-19)。为了评估抗病毒药物特力阿扎维林治疗COVId-19的有效性和安全性,本研究针对感染COVId-19的成年住院患者开展了一项随机双盲对照试验。本研究从10个分中心招募COVId-19患者,并将患者按1:1的比例随机分为两组。试验组的患者每天服用250 mg的特力阿扎维林药物3~4次,对照组患者则服用安慰剂,为期共7 d。主要结局指标为临床改善时间,临床改善时间的定义为随机分组28d内患者的体温、呼吸频率、血氧饱和度、咳嗽频率和肺CT(计算机断层扫描,computed tomography)所显示的肺部感染吸收情况全部恢复正常的时间。次要结局指标包括主要结局指标的5个组成指标,及肺部感染吸收的平均时间和吸收比例,以及用咽拭子采样法连续两次SARS-CoV-2核酸检测阴性的转阴率。与此同时,记录合并的治疗药物、不良事件和严重不良事件。由于需要进行住院治疗的新增感染病例的减少,本研究在招募52名患者后便停止招募。将52名受试者随机分为服用特力阿扎维林药物的试验组(n=26)和服用安慰剂的对照组(n=26)。结果显示,两组临床改善时间并无明显差异[中位数,7 d vs.12 d;风险比(RR)为2.0;95%置信区间(CI)为0.7~5.6;p=0.2]。服用特力阿扎维林的试验组中有10名患者发生临床改善,服用安慰剂的对照组中有6名患者出现临床改善(38.5%vs.23.1%,RR为2.1;95%CI为0.6~7.0;p=0.2)。除了肺部感染的吸收情况外(试验组50.0%,对照组26.1%),其余主要结局所观察指标均在28 d内恢复正常。此外,试验组的患者在呼吸系统、心脏、肾、肝或凝血功能等方面的合并治疗较对照组少。尽管特力阿扎维林药物对COVId-19患者的疗效尚未达到统计学上的显著性水平,但本研究结果表明,由于特力阿扎维林药物具有抗病毒作用,将其用于COVId-19的治疗也可能具有一定的疗效。对此,需要进一步的研究进行验证。

关键词：新型冠状病毒肺炎特力阿扎维林有效性安全性

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