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Journal of mountain Science 2015年第3期12卷 558-570页

作者： Parveen Kumar CHHETRI David m.CAIRNS Department of Geography Texas A&M UniversityCollege Station

Treeline ecotone dynamics of Abies spectabilis （D. don） mirb. in the Barun valley, makalu Barun National Park, eastern Nepal Himalaya were studied by establishing seven plots （20 m x variable length） from the foresfline to the tree species limit： three plots on the south- and north-facing slopes each （S1-S3, N1-N3）, and one plot on the east- facing slope （E） in the relatively undisturbed forests. A dendroecological method was used to study treeline advance rate and recruitment pattern. In all the plots, most trees established in the early 20th century, and establishment in the second half of the 20th century was confined to the foresfline area. Treeline position has not advanced substantially in the Barun valley, with 0nly 22 m average elevational shift in the last 13o years, and with average current shifting rate of 14 cm/yr. moreover, no significant relationship was found between tree age and elevation on the south-, north-, and east-facing slopes. The number of seedlings and saplings in near the treeline area was negligible compared to that near the foresfline area. Therefore, A. spectabilis treeline response to the temperature change was slow, despite the increasing temperature trend in the region. Beside the temperature change, factors such as high inter-annual variability in temperature, dense shrub cover, and local topography also play an important role in treeline advance and controlling recruitment pattern above the treeline.

关键词： Climate change Treeline ecotone Treeline advance Recruitment pattern

The size-dependent elastohydrodynamic lubrication contact of a coated half-plane with non-Newtonian fluid

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Applied mathematics and mechanics(English Edition) 2021年第7期42卷 915-930页

作者： Jie SU Hongxia SONG Liaoliang KE S.m.AIZIKOVICH School of mechanical Engineering Tianjin UniversityTianjin 300350China School of mathematical Science Inner Mongolia UniversityHohhot 010021China Laboratory of Functionally Graded and Composite materials Research and Education Center"Materials"Don State Technical UniversityRostov-on-Don 344000Russia

Based on the couple-stress theory,the elastohydrodynamic lubrication(EHL)contact is analyzed with a consideration of the size *** lubricant between the contact surface of a homogeneous coated half-plane and a rigid punch is supposed to be the non-Newtonian *** density and viscosity of the lubricant are dependent on fluid *** of film thickness,in-plane stress,and fluid pressure are calculated by solving the nonlinear fluid-solid coupled equations with an iterative *** effects of the punch radius,size parameter,coating thickness,slide/roll ratio,entraining velocity,resultant normal load,and stiffness ratio on lubricant film thickness,in-plane stress,and fluid pressure are *** results demonstrate that fluid pressure and film thickness are obviously dependent on the size parameter,stiffness ratio,and coating thickness.

关键词： elastohydrodynamic lubrication(EHL) non-Newtonian fluid size effect couple-stress theory coating

浅层高分辨率地震反射法在各种环境问题中的应用

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国外地质勘探技术 1996年第3期 10-15页

作者： Richard D.miller don W.Steeples 张翠兰

浅层地震反射法已成功地应用于各种地质下沉和环境问题。记录仪器的动态范围的增大、处理硬件和软件费用的降低、使地震反射法成为一种具有高性能价格比的手段而应用于浅层目标成象之中。许多地区的地震资料都具有很高的分辨率,能探测... 详细信息

浅层地震反射法已成功地应用于各种地质下沉和环境问题。记录仪器的动态范围的增大、处理硬件和软件费用的降低、使地震反射法成为一种具有高性能价格比的手段而应用于浅层目标成象之中。许多地区的地震资料都具有很高的分辨率,能探测出小于3m位移造成的断层以及仅1m厚的地层。目前,我们已经探测到了仅2m深的浅层反射,还可以探测并成象地下20m内与废弃煤矿有关的地下空穴;地震反射法已成功地应用于受盐岩溶蚀矿影响的地下区域的成象;利用地震反射所探测和追踪到的一个地堑表明是一个化学储存池漏液渗析的优选路径。这些实例分析表明,浅层高分辨率地震反射法具有很大的应用潜力,可以既经济又高效地应用于预防和/或解决许多环境问题。

关键词：地震勘探高分辨率地震反射法环境地质

At the Intersection： merging Ca2＋ and ROS Signaling Pathways in Pollen

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molecular Plant 2014年第11期7卷 1595-1597页

作者： michael m. Wudick José A. Feijó Department of Cell Biology and molecular Genetics University of Maryland College Park MD 20742–5815 USA Instituto Gulbenkian de Ciencia 2780-156 Oeiras Portugal

THE mIXED BLESSING OF ROS： don＇T YOU KNOW THAT I＇m TOXIC？Due to plants＇ aerobic metabolism, reactive oxygen species （ROS） continuously accrue in different tissues and organs as a by-product of many metabolic reactions. Despite their toxic activity, plants also rely on ROS as a major form of second messenger to integrate, induce, and/or propagate biotic and abiotic signals and signaling cascades. Being small, short-lived, and rapidly diffusible makes ROS ideal messenger molecules for local biochemi- cal reactions. Hence, a delicate fine-tuning of localized ROS production and signaling events is crucial for many physi- ologic processes.

关键词： PROTEIN-KINASE CIPK26 NADPH OXIDASE SENSORS CBL1 TUBE GROWTH TIP GROWTH CHANNEL

A stochastic approach for integrating market and technical uncertainties in economic evaluations of petroleum development

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Petroleum Science 2009年第3期6卷 319-326页

作者： Changhyup Park Joe m. Kang Taewoong Ahn BK21 Research Division for Energy Resources Seoul National University Division of Energy Systems Engineering Seoul National University

The paper presents a stochastic and economic analysis for petroleum development under uncertain market and technical environments. mean-reversion with jumps for price forecasting is used to consider market uncertainty, while various scenarios for the reservoir properties and cost are employed to consider technical uncertainty. monte Carlo simulation is carried out to obtain the feasible range of net present values and internal rates of return. The influence of stochastic parameters is examined through correlation coefficients. The stochastic approach yields more reliable evaluation and effectively investigates the characteristics of development. The integration of uncertainties and contractual terms results in an irregular tendency in the future cash flow and reveals that a larger reserve does not guarantee a greater profit. The reserve and the well rate affect the economic values whereas the parameters for price prediction don＇t. The research confirms the necessity of qualifying uncertainties for realistic decision-making at the initial stage of development.

关键词： Uncertainty petroleum development decision-making stochastic approach mean reversion with jumps

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卢卡诺伯爵

Aspirin use for primary prophylaxis: Adverse outcomes in non-variceal upper gastrointestinal bleeding

丛书名：西班牙文学名著丛书

1996年

作者：（西班牙）堂胡安·曼努埃尔（don Juan manuel）申宝楼译

全书有51个故事组成，以卢卡诺伯爵和他的谋士帕特罗尼向奥两个人为轴线贯串始终，以他们两个人之间的谈话为主要叙事形式，开创了西班牙小说创作的先声，也是欧洲小说创作的先声。

ISBN: (纸本)7207031173

关键词：长篇小说地点:西班牙年代:中世纪

来源：汇雅图书（南通市图书馆... 评论

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世界胃肠外科杂志：英文版（电子版） 2016年第7期8卷 501-507页

作者： Karina m Souk Hani m Tamim Hussein A Abu Daya don C Rockey Kassem A Barada Department of Internal medicine American University of Beirut-Medical Center Biostatistics Support Unit Clinical Research Institute American University of Beirut-Medical Center Department of Internal medicine University of Pittsburgh Medical Center Department of Internal medicine the Medical University of South Carolina Division of Gastroenterology and Hepatology American University of Beirut-Medical Center

AIm: To compare outcomes of patients with nonvariceal upper gastrointestinal bleeding(NVUGIB) taking aspirin for primary prophylaxis to those not taking ***: Patients not known to have any vascular disease(coronary artery or cerebrovascular disease) who were admitted to the American University of Beirut medical Center between 1993 and 2010 with NVUGIB were included. The frequencies of in-hospital mortality, re-bleeding, severe bleeding, need for surgery or embolization, and of a composite outcome defined as the occurrence of any of the 4 bleeding related adverse outcomes were compared between patients receiving aspirin and those on no antithrombotics. We also compared frequency of in hospital complications and length of hospital stay between the two ***: Of 357 eligible patients, 94 were on aspirin and 263 patients were on no antithrombotics(controlgroup). Patients in the aspirin group were older, the mean age was 58 years in controls and 67 years in the aspirin group(P more co-morbidities, including diabetes mellitus and hypertension [25(27%) vs 31(112%) and44(47%) vs 74(28%) respectively,(P = 0.001)], as well as dyslipidemia [21(22%) vs 16(6%), P moking was more frequent in the aspirin group [34(41%) vs 60(27%), P = 0.02)]. The frequencies of endoscopic therapy and surgery were similar in both groups. Patients who were on aspirin had lower inhospital mortality rates(2.1% vs 13.7%, P = 0.002),shorter hospital stay(4.9 d vs 7 d, P = 0.01), and fewer composite outcomes(10.6% vs 24%, P = 0.01). The frequencies of in-hospital complications and re-bleeding were similar in the two ***: Patients who present with NVUGIB while receiving aspirin for primary prophylaxis had fewer adverse outcomes. Thus aspirin may have a protective effect beyond its cardiovascular benefits.

关键词： Aspirin morbidity mortality Non-variceal upper gastrointestinal bleeding Outcomes

Dissolved Organic Nitrogen in mediterranean Ecosystems

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Pedosphere 2011年第3期21卷 309-318页

作者： m.DELGADO-BAQUERIZO F.COVELO A.GALLARDO Department of Physical Chemical and Natural Systems University Pablo de Olavide Ctra. de Utrera km.1Seville 41013 (Spain)

Dissolved organic nitrogen （don） in soils has recently gained increasing interest because it may be both a direct N source for plants and the dominant available N form in nutrient-poor soils, however, its prevalence in mediterranean ecosystems remains unclear. The aims of this study were to i） estimate soil don in a wide set of mediterranean ecosystems and compare this levels with those for other ecosystems; ii） describe temporal changes in don and dissolved inorganic nitrogen （DIN） forms （NH＋ and NO3）, and characterize spatial heterogeneity within plant communities; and iii） study the relative proportion of soil don and DIN forms as a test of Schimel and Bennett＇s hypothesis that the prevalence of different N forms follows a gradient of nutrient availability. The study was carried out in eleven plant communities chosen to represent a wide spectrum of mediterranean vegetation types, ranging from early to late successional status. don concentrations in the studied mediterranean plant communities （0-18.2 mg N kg-1） were consistently lower than those found in the literature for other ecosystems. We found high temporal and spatial variability in soil don for all plant communities. As predicted by the Schimel and Bennett model for nutrient-poor ecosystems, don dominance over ammonium and nitrate was observed for most plant communities in winter and spring soil samples. However, mineral-N dominated over don in summer and autumn. Thus, soil water content may have an important effect on don versus mineral N dominance in mediterranean ecosystems

关键词： dissolved inorganic nitrogen nitrogen cycle soil ammonium soil N availability soil nitrate

Clones identification of Sequoia sempervirens (D. don) Endl. in Chile by using PCR-RAPDs technique

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第2期10卷 112-119页

作者： manuel TORALIBAEZ margarita CARU miguel A. HERRERA Luis GONZALEZ Luis m. mARTIN Jorge mIRANDA Rafael m. NAVARRO-CERRILLO Department of Forest management Faculty of ForestryUniversity of Chile Santa Rosa 11315La PintanaSantiagoChile Department of Ecological Sciences Faculty of SciencesUniversity of ChileSanta Rosa 11315La PintanaSantiagoChile Department of Forestry School of Agriculture and Forestry University of Córdoba14080 CórdobaSpain Department of Genetic School of Agriculture and ForestryUniversity of Córdoba14080 CórdobaSpain Department of Forest management Faculty of ForestryUniversity of ChileSanta Rosa 11315La PintanaSantiagoChile

A protocol of polymerase chain reaction-random amplified polymorphic DNAs (PCR-RAPDs) was established to analyse the gene diversity and genotype identification for clones of Sequoia sempervirens (D. don) Endl. in Chile. Ten (out of 34) clones from introduction trial located in Voipir-Villarrica, Chile, were studied. The PCR-RAPDs technique and a modified hexadecyltrimethylammonium bromide (CTAB) protocol were used for genomic DNA extraction. The PCR tests were carried out employing 10-mer random primers. The amplification products were detected by electrophoresis in agarose gels. Forty nine polymorphic bands were obtained with the selected primers (BG04, BF07, BF12, BF13, and BF14) and were ordered according to their molecular size. The genetic similarity between samples was calculated by the Jaccard index and a dendrogram was con- structed using a cluster analysis of unweighted pair group method using arithmetic averages (UPGmA). Of the primers tested, 5 (out of 60) RAPD primers were selected for their reproducibility and high polymorphism. A total of 49 polymorphic RAPD bands were detected out of 252 bands. The genetic similarity analysis demonstrates an extensive genetic variability between the tested clones and the dendrogram depicts the genetic relationships among the clones, suggesting a geographic relationship. The results indicate that the RAPD markers permitted the identification of the assayed clones, although they are derived from the same geo- graphic origin.

关键词： Sequoia sempervirens (D. don) Endl. Random amplified polymorphic DNAs (PCR-RAPDs) molecular markers Clone assays Chile Genetic relationships

华北地台北缘集宁地区古元古代片麻状石榴花岗岩的深熔成因及地质意义

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岩石学报 2018年第9期34卷 2754-2772页

作者：石强董晓杰徐仲元关庆彬李鹏川张超崔芳华吉林大学地球科学学院长春130061 山东理工大学资源与环境工程学院淄博255000

本文对华北克拉通北缘集宁地区空间上密切共生的片麻状石榴花岗岩和孔兹岩系富铝片麻岩的岩相学、地球化学及年代学特征进行了对比研究。SHRImP锆石U-Pb定年方面,在富铝片麻岩中获得了1910±10ma和1839±13ma变质锆石年龄,在片麻状石榴... 详细信息

本文对华北克拉通北缘集宁地区空间上密切共生的片麻状石榴花岗岩和孔兹岩系富铝片麻岩的岩相学、地球化学及年代学特征进行了对比研究。SHRImP锆石U-Pb定年方面,在富铝片麻岩中获得了1910±10ma和1839±13ma变质锆石年龄,在片麻状石榴花岗岩中获得了1919±17ma的变质重结晶锆石年龄。在石榴花岗岩的石榴石包裹体中识别出与富铝片麻岩相对应的进变质阶段(m1)和峰期阶段(m2)的矿物组合,由此确认富铝片麻岩的变质作用和导致石榴花岗岩形成的深熔作用是同一构造热事件的产物。通过对二者变质作用演化及特征变质矿物的对比,认为深熔作用主要发生在峰期后等温降压阶段(m3),石榴花岗岩中的石榴石为深熔作用过程中的残留矿物相或转熔矿物相,而石榴花岗岩则是混合有大量残留矿物相的熔体结晶的产物。对片麻状石榴花岗岩和富铝片麻岩的地球化学组成特征进行了对比分析,片麻状石榴花岗岩既有一定的继承性,又有十分明显的变异性。变异性表现为:1)石榴花岗岩主量和微量元素含量分布极不均匀,微量元素含量普遍低于源岩(Cs、Rb、Th、U、Nb、Ta、Zr、Hf等);2)大离子亲石元素Cs和生热元素U、Th亏损明显,Sr相对富集;3)高场强元素Nb、Ta、P、Ti的明显亏损;4)铕异常变化大,存在铕富集型、铕平坦型和铕亏损型共存的稀土配分曲线的岩石,这是深熔成因石榴花岗岩最突出的表现,也可能是原地-半原地深熔花岗岩的主要地球化学标志。综合区域上的地质资料,认为深熔作用与碰撞后伸展构造背景下基性岩浆底侵事件有关。

关键词：古元古代孔兹岩系 SHRImP锆石U-Pb测年片麻状石榴花岗岩深熔作用集宁