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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

1999年

作者： Ashok Saxena, Stephen D. Antolovich, thomas h. Sanders, jr., Steven B. Warner James P. Schaffer

来源：畅想之星图书光盘版（南... 评论

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Ecological Processes 2024年第1期13卷 132-143页

作者： Luiz Santini jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena Torres Fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-Gonzalez hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

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衬衫面料的Tough Cotton整理

纺织导报 2009年第5期 79-80,82页

作者： h. Kenneth Greeson jr. James E. Rowe 美国棉花公司

Tough Cotton技术早在2005年就作为一项创新的防皱整理技术而公布于世，最初是用于厚重斜纹织物的整理。从那时起，人们开始对100％棉衬衫面料进行研究，关注点为白度和耐久压烫效果。通过化学整理剂和应用条件的优化，能够在保持可以... 详细信息

Tough Cotton技术早在2005年就作为一项创新的防皱整理技术而公布于世，最初是用于厚重斜纹织物的整理。从那时起，人们开始对100％棉衬衫面料进行研究，关注点为白度和耐久压烫效果。通过化学整理剂和应用条件的优化，能够在保持可以接受的强度的同时达到最佳抗皱和白度效果。

关键词：整理技术衬衫面料化学整理剂斜纹织物白度防皱压烫耐久

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SiDaCoS: Product and Process Models on Construction Sites

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SiDaCoS: Product and Process Models on Construction Sites

用面积平衡原理预测伸展断陷盆地中岩层内部应变及亚分辨正断层的方法

国际桥梁2004年大会

作者： Jan REINhARDT James h.GARRETT jr. Burcu AKINCI Assistant Engineer Turner Construction Company ArlingtonVA USA. Professor of Civil Engineering at Carnegie Mellon University. Professor of Civil Engineering at Carnegie Mellon University. Assislant Professor of Civil Enginccring at Carncgic Mellon University.

＜正＞ In the future, product and process models will handle and store information relevant for all phases of a construction project. For many project management tasks this information needs to be accessed and updated locally at the construction site. Due to the complexity of product and process models, such data access and data collection tasks are challenging from a human computer interaction perspective. In order to interact with information contained in product and process models, users on construction sites need information contained in these mo’dels in flexible representations corresponding to the specific task and the environment of the user. The Site Data Collection System （SiDaCoS） described in this paper provides data access and data collection support that is effective and more efficient compared to existing systems.

关键词： data collection construction management product and process models system architecture mobile computing.

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地球科学（中国地质大学学报） 2002年第6期27卷 696-702页

作者：漆家福 Groshong R h jr.杨桥教育部石油天然气成藏机理重点实验室北京102249 Department of Geological Sciences

大多数地堑和半地堑是由深度近水平的拆离正断层控制的 .根据面积平衡原理 ,这些伸展断陷盆地岩层的区域基准面至拆离断层面高度 (h)与其损失面积 (S)呈线性比例 .拆离断层之上的盆地基底岩层的水平伸展量相同 ,因此 ,用“S -h图解法”... 详细信息

大多数地堑和半地堑是由深度近水平的拆离正断层控制的 .根据面积平衡原理 ,这些伸展断陷盆地岩层的区域基准面至拆离断层面高度 (h)与其损失面积 (S)呈线性比例 .拆离断层之上的盆地基底岩层的水平伸展量相同 ,因此 ,用“S -h图解法”可以确定拆离断层深度 ,并能在此基础上计算出岩层的总水平伸展量 .伸展盆地中的总水平伸展量主要是由不同尺度的正断层的水平离距体现出来的 .可观测解释的断层的水平位移可以通过测量盆地宽度、岩层长度等直接得到 .用剖面面积平衡方法可计算出盆地各岩层的平行岩层面的应变 ,其中相当部分是由在观测尺度上不能直接解释出来的“亚分辨正断层”的小尺度位移造成的 .因此 ,在分析伸展断陷盆地的构造样式、岩层力学性质基础上 ,有可能对计算得到的平行岩层的伸展应变进行合理评估 ,进而可以定量地预测“亚分辨正断层”的密度和可能的分布部位 .

关键词：伸展断陷盆地岩层面积平衡伸展应变亚分辨断层地堑半地堑 S-h图解

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Schistosomiasis is more prevalent than previously thought:what does it mean for public health goals,policies,strategies,guidelines and intervention programs?

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Infectious Diseases of Poverty 2017年第1期6卷 540-547页

作者： Daniel G.Colley Tamara S.Andros Carl h.Campbell jr Schistosomiasis Consortium for Operational Research and Evaluation(SCORE) Center for Tropical and Emerging Global Diseases(CTEGD)University of Georgia500 DW Brooks DriveRoom 330B Coverdell CenterAthensGeorgia 30602USA Department of Microbiology University of GeorgiaAthensGeorgia 30602USA

Mapping and diagnosis of infections by the three major schistosome species(Schistosoma haematobium,*** and ***)has been done with assays that are known to be specific but increasingly insensitive as prevalence declines or in areas with already low prevalence of *** becomes a true challenge to achieving the goal of elimination of schistosomiasis because the multiplicative portion of the life-cycle of schistosomes,in the snail vector,favors continued transmission as long as even a few people maintain low numbers of worms that pass eggs in their *** mapping tools based on detection of worm antigens(circulating cathodic antigen-CCA;circulating anodic antigen-CAA)in urine of those infected are highly sensitive and the CAA assay is reported to be highly *** these tools in areas of low prevalence of all three of these species of schistosomes has demonstrated that more people harbor adult worms than are regularly excreting eggs at a level detectable by the usual stool assay(Kato-Katz)or by urine *** very low prevalence areas this is sometimes 6-to10-fold *** with what appears to be a sizable population of“egg-negative/worm-positive schistosomiasis”especially in areas of very low prevalence,national NTD programs are confounded about what guidelines and strategies they should enact if they are to proceed toward a goal of *** is a critical need for continued evaluation of the assays involved and to understand the contribution of this“egg-negative/worm-positive schistosomiasis”condition to both individual morbidity and community *** is also a critical need for new guidelines based on the use of these more sensitive assays for those national NTD programs that wish to move forward to strategies designed for elimination.

关键词： Schistosomiasis mansoni Circulating cathodic antigen Kato-Katz Mapping Diagnosis

Best Bounds on Measures of Risk and Probability of Ruin for Alpha Unimodal Random Variables When There Is Limited Moment Information

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Applied Mathematics 2016年第8期7卷 765-783页

作者： Patrick L. Brockett Samuel h.Cox, jr. Richard D. MacMinn Bo Shi Department of Information Risk and Operations Management University of Texas Austin TX USA Robinson College of Business Georgia State University Atlanta GA USA Center for Risk Management University of Texas Austin TX USA National Chengchi University Taipei City College of Business and Technology Morehead State University Morehead KY USA

This paper presents explicit formulae giving tight upper and lower bounds on the expectations of alpha-unimodal random variables having a known range and given set of moments. Such bounds can be useful in ordering of random variables in terms of risk and in PERT analysis where there is only incomplete stochastic information concerning the variables under investigation. Explicit closed form solutions are also given involving alpha-unimodal random variables having a known mean for two particularly important measures of risk—the squared distance or variance, and the absolute deviation. In addition, optimal tight bounds are given for the probability of ruin in the collective risk model when the severity distribution has an alpha-unimodal distribution with known moments.

关键词： Alpha-Unimodal Bounds on Risk Measures Partial Moment Knowledge Actuarial Applications Measures of Dispersion

Astigmatic correction with implantation of a light adjustable vs monofocal lens: a single site analysis of a randomized controlled trial

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International Journal of Ophthalmology(English edition) 2019年第7期12卷 1101-1107页

作者： Majid Moshirfar William D.Wagner Steven h.Linn David F.Skanchy Tanner W.Brown Aaron T.Gomez Jackson L.Goldberg Yasmyne C.Ronquillo Phillip C.hoopes jr. hDR Research Center Hoopes VisionDraper UT 84020USA John A. Moran Eye Center Department of Ophthalmology and Visual SciencesUniversity of Utah School of MedicineSalt Lake CityUT 84132USA Utah Lions Eye Bank MurrayUT 84107USA Virginia Commonwealth University School of Medicine RichmondVA23298USA McGovem Medical School at the University of Texas health Science Center HoustonTX77030USA The University of Texas Rio Grande Valley School of Medicine EdinburgTX78539USA

AIM: To evaluate the light adjustable lens(LAL) vs a standard monofocal lens in achieving target astigmatic refraction and improving postoperative uncorrected distance visual acuity(UDVA). METhODS: This randomized controlled clinical trial included 40 patients with pre-existing astigmatism and visually significant cataract. Twenty-eight patients received the LAL and 12 control patients received a monofocal intraocular lens(IOL) after cataract extraction at a single institution. The patients with the LAL underwent adjustment by ultraviolet(UV) light postoperatively plus subsequent lock-in procedures and all patients returned to clinic for follow up of study parameters at 6, 9, and 12 mo. Manifest refraction, distance visual acuity, and adverse events were recorded at each ***: The mean cylinder before adjustment in eyes with the LAL was-0.89±0.58 D(-2.00 to 0.00 D) and-0.34±0.34 D(-1.25 to 0.00 D) after lock-in(P=1.68 x10-8). The mean cylinder in patients with the monofocal lens was-1.00±0.32 D(-1.50 to-0.50 D) at 17-21 d postoperatively, which was statistically different from the LAL cylinder postlock-in(P=1.43 x10-6). UDVA in the LAL group was 20/20 or better in 79% of patients post lock-in with good stability over 12 mo compared with 33% of the control patients with UDVA of 20/20 or better. CONCLUSION: These results demonstrate that the LAL is more effective in achieving target refractions and improving postoperative UDVA in patients with pre-existing corneal astigmatism than a standard monofocal lens.

关键词： light adjustable lens monofocal lens astigmatism cataract

金属硫化物NMTS-2吸附剂研制及去除水中锶的研究

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金属硫化物NMTS-2吸附剂研制及去除水中锶的研究

作者： Varney Kromah,jr. 天津大学

学位级别：硕士

近年来随着核工业的快速发展,以及福岛和切尔诺贝利核电站泄漏事故,引起公众对水体放射性污染的广泛关注。放射性锶是核燃料的主要裂变产物之一和核废物的主要组分,半衰期长,在水环境中有较强的迁移性,危害人类健康和环境,因此研究如何... 详细信息

近年来随着核工业的快速发展,以及福岛和切尔诺贝利核电站泄漏事故,引起公众对水体放射性污染的广泛关注。放射性锶是核燃料的主要裂变产物之一和核废物的主要组分,半衰期长,在水环境中有较强的迁移性,危害人类健康和环境,因此研究如何从水中分离去除Sr非常重要。采用水热法合成了一种含钠、锰、锡和硫的金属硫化物吸附剂(NMTS-2),通过改变锰的用量、水量、反应温度和反应时间等优化吸附剂的合成。此外,为进一步降低成本,用锡盐替代金属锡,且控制锡盐的用量最低,同时保持了较高的Sr去除率;与Na ZTS和Na TS的相比,NMTS-2的原料分别下降69%和76%。合成NMTS-2的优化原料配比为1.150 kg NaCO/kg、0.550 kg Mn SO/kg、0.411 kg Sn Cl/kg、0.696 kg S/kg、0.361 kg hO/kg,优化反应条件和参数为200°C和24小时。采用SEM、XPS、PXRD等多种手段表征NMTS-2的形貌特征、元素组成和结构稳定性,发现元素均匀分布在吸附剂表面,其在p h值不低于4时能够保持化学稳定性,低于365℃时保持热稳定性。为确定NMTS-2对水中Sr的吸附特性,完成了吸附动力学、等温线、影响因素和吸附选择性的研究,结果表明:NMTS-2吸附水中初始浓度为5.000mg/L的Sr,在5min后达到吸附平衡,符合拟二级动力学模型;298 K时最佳拟合吸附等温线符合Langmuir吸附等温模型,最大吸附量为47.04 mg/g,与实验值46.10 mg/g非常吻合;吸附剂投加量为0.5000 g/L、初始Sr浓度为5.000mg/L、NMTS-2在p h值为4-12时,对Sr的去除率为96.81%-99.96%,分配系数(K)为6.06×10-4.70×10 m L/g;水中共存离子会降低Sr的吸附去除率,影响顺序为Ca>Mg>>Na>K;NMTS-2对自来水和湖水的锶具有优异的吸附选择性;此外,NMTS-2吸附去除Sr的机理为离子交换和配位作用,去离子水中Sr的解吸速率可以忽略不计。综上所述,即使在强酸性或强碱性的放射性废水中,NMTS-2对放射性Sr的吸附也具有快速、有效和高选择性,可以为放射性含锶废水的应急处理提供支持。

关键词：放射性污染水四元金属硫化物吸附剂NMTS-2 制备优化高选择性

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洋中脊热液交代过程的实验与理论研究

地质地球化学 1989年第2期17卷 41-48页

作者： W.E.Seyfried jr. 丁抗

通过对辉绿岩的高温高压交代实验及理论计算,研究了洋中脊的热液交代过程。这一交代过程的存在可以从洋中脊的热液化学组成、挖掘到的变质玄武岩样品的化学、矿物学以及陆地上的蛇绿岩露头得到证实。所获结果表明,Mg、Ca、Na的固定反应... 详细信息

通过对辉绿岩的高温高压交代实验及理论计算,研究了洋中脊的热液交代过程。这一交代过程的存在可以从洋中脊的热液化学组成、挖掘到的变质玄武岩样品的化学、矿物学以及陆地上的蛇绿岩露头得到证实。所获结果表明,Mg、Ca、Na的固定反应分别发生在不同的交代条件下。Mg的固定反应发生在海底热液对流圈的下降翼,Ca、Na的固定主要和上升翼有关,其中Ca反应发生于深部,Na反应则位于上升翼近于海底的部位。热液中Ca的迁出,伴随着h^+的产生。减压过程大大地增进了这一反应。和其他含钙交代相相比,绿帘石的稳定性也因此而提高。在热液体系中,绿帘石和斜长石这两个固溶体制约着热液的化学成分和ph值。东太平洋隆起21°N黑烟囱中喷出的热液来自于385—400℃、300—400bar的反应带。只要弄清了盐度的影响、由传导冷却而造成的退变质过程以及混合过程,就可确定所有热液的反应带的温压条件。

关键词：洋中脊热液交代作用地球化学

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