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Journal of Integrative plant biology 2008年第11期50卷 1388-1395页

作者： Joy K.Ward David A.Myers Richard b.Thomas Department of Ecology and Evolutionary biology University of Kansas Department of biology West Virginia University

During the last ice age, CO2 concentration （[CO2]） was 180-200 umol/mol compared with the modern value of 380 umol/mol, and global temperatures were -8 ℃ cooler. Relatively little is known about the responses of C3 and C4 species to longterm exposure to glacial conditions. Here Abutilon theophrasti Medik. （C3） and Amaranthus retroflexus L. （C4） were grown at 200 umol/mol CO2 with current （30/24℃） and glacial （22/16℃） temperatures for 22d. Overall, the C4 species exhibited a large growth advantage over the C3 species at low [CO2]. However, this advantage was reduced at low temperature, where the C4 species produced 5x the total mass of the C3 species versus 14x at the high temperature. This difference was due to a reduction in C4 growth at low temperature, since the C3 species exhibited similar growth between temperatures. physiological differences between temperatures were not detected for either species, although photorespiration/net photosynthesis was reduced in the C3 species grown at low temperature, suggesting evidence of improved carbon balance at this treatment. This system suggests that C4 species had a growth advantage over C3 species during low [CO2] of the last ice age, although concurrent reductions in temperatures may have reduced this advantage.

关键词： Abutilon theophrasti Amaranthus retroflexus C3 species C4 species climate change low CO2 low temperature photorespiration pleistocene.

Natural killer cell-triggered vascular transformation:maternal care before birth?

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Cellular & Molecular Immunology 2011年第1期8卷 1-11页

作者： Jianhong Zhang Zhilin Chen Graeme N Smith b.Anne Croy Department of Anatomy and Cell biology Queen’s UniversityKingstonONCanada Department of Obstetrics and Gynecology Queen’s UniversityKingstonONCanada

Natural killer(NK)cells are found in lymphoid and non-lymphoid *** addition to important roles in immune surveillance,some NK cells contribute to angiogenesis and circulatory *** uterus of early pregnancy is a non-lymphoid organ enriched in NK cells that are specifically recruited to placental attachment *** species with invasive hemochorial placentation,these uterine natural killer(uNK)cells,via secretion of cytokines,chemokines,mucins,enzymes and angiogenic growth factors,contribute to the physiological change of mesometrial endometrium into the unique stromal environment called decidua *** humans,uNK cells have the phenotype CD56^(bright) CD16^(dim) and they appear in great abundance in the late secretory phase of the menstrual cycle and early *** expression studies indicate that CD56^(bright) CD16^(dim) uterine and circulating cells are functionally *** humans but not mice or other species with post-implantation decidualization,uNK cells may contribute to blastocyst implantation and are of interest as therapeutic targets in female *** and genetic studies in mice first identified triggering of the process of gestation spiral arterial modification as a major uNK cell function,achieved via interferon(IFN)-c *** spiral arterial modification,branches from the uterine artery that traverse the endometrium/decidua transiently lose their muscular coat and ability to *** expression of vascular markers changes from arterial to venous as these vessels dilate and become low-resistance,high-volume *** understanding of the vascular interactions of human uNK cells is difficult to obtain because endometrial time-course studies are not possible in pregnant *** we briefly review key information concerning uNK cell functions from studies in rodents,summarize highlights concerning human uNK cells and describe our preliminary studies on development of a humanized,pregnant

关键词： decidua humanized mice pregnancy uterine natural killer cell

Structure and Thermal parameters of Ni_(20)pd_(80) Alloy

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Journal of Materials Science & Technology 2009年第2期25卷 208-210页

作者： S. Ahmad A.b. Ziya A. Aziz Z.I. Zafar Department of physics Bahauddin Zakariya University Department of Chemistry Bahauddin Zakariya University

The structure and thermal parameters of Ni20pd80 alloy were studied by X-ray diffraction（XRD）. The diffraction experiments performed in the temperature range of 308-1100 K revealed that the alloy formed a face centered cubic （fcc） Al-type structure. The temperature dependence of the lattice parameters was investigated by using the bragg line displacement method showing that the lattice parameter increases with the increase of temperature. The mean linear thermal expansion （MLTE（%））, coefficient of thermal expansion （CTE, α）, the characteristic Debye temperature （（θD） and mean square amplitudes of vibration were determined from XRD data. The value of Debye temperature was found to be 253 K. It was found that temperature factor was independent of the static displacements.

关键词： Alloys Structure Thermal parameters X-ray diffraction (XRD)

Topological dependence of mechanical responses of solidification microstructures in aluminum brazed joints

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中国有色金属学会会刊：英文版 2003年第6期13卷 1296-1300页

作者：高峰钱乙余 D.p.Sekulic 马鑫 F.Yoshida State Key Laboratory of Advanced production Technology Center for Robotics and Manufacturing Systems Department of Mechanical System Engineering

The main objective is to provide an evidence of spatial dependence of mechanical responses of a heterogeneous aluminum brazed joint re-solidified clad, and to confirm a sufficient sensitivity of a nano-indentation—load curve method for identifying the dependence. Topological features of a network of solidification microstructures(α phase and eutectic), formed during quench in a brazing process of aluminum alloy, influence significantly dynamic mechanical responses of resulting heterogeneous material. Nano/micro indentation depth vs load characteristics of differing phases suggest a spatially sensitive mechanical response of a re-solidified fillet in the joint zone. Hence, a spatial distribution, pattern formations and other morphological characteristics of microstructures have a direct impact on an ultimate joint integrity. Topology-induced variations of indentation—load curves was presented. A hypothesis involving microstructures’ spatial distribution vs mechanical response was formulated.

关键词：铝铜焊显微结构凝固拓扑相关机械响应焊接铝合金

Simplified seismic fatigue evaluation for rigid steel connections

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 245-253页

作者： AymanA.Shama John b.Mander Stuart.S.Chen parsons Corporation 100 BroadwayNew York.NY 10005USA Ph.D.P.E Department of Civil Engineering University of CanterburyNew Zealand Professor Department of Civil Structural & Environmental EngineeringState University of New York at BuffaloBuffaloNY 14260USA Associated Professor

A simplified fatigue-life model is proposed for assessing the seismic inelastic rotational capacity of steel *** relations are developed for rigid steel connections under lateral *** this is extended to account for the effects of the welded steel moment frame(WSMF)connections of the so-called pre-Northridge *** seismic fatigue theory is validated against experimental *** experiments were conducted under increasing ductility amplitudes until the onset of ***'rule was used to convert the test results to given an equivalent constant amplitude cyclic fatigue *** agreement is obtained when comparing the experimental observations with the theoretical predictions.

关键词： fatigue cyclic load seismic pile-to-cap moment frames connections steel

The Novel Mechanical property of Tongue of a Woodpecker

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Journal of bionic Engineering 2009年第3期6卷 214-218页

作者： p Zhou X Q Kong C W Wu Z Chen National Key Laboratory for Structural Analysis of Industrial Equipment Dalian University of Technology Department of Civil and Environmental Engineering University of Missouri

biomaterials such as bone,teeth,nacre and silk are known to have superior mechanical properties due to their specific nanocomposite *** we report that the woodpecker's tongue exhibits a novel strength and flexibility due to its special composite micro/*** tongue consists of a flexible cartilage-and-bone skeleton covered with a thin layer tissue of high strength and *** the interface between the cartilage-and-bone skeleton and the tissue layer,there is a hierarchical fiber-typed *** is this special design of the tongue that makes the woodpeckers efficient in catching the insects inside *** special micro/nanostructures of the woodpecker's tongue show us a potential method to enhance the interfacial connection between soft and hard material layers for bio-inspired composite system designs.

关键词： woodpeckcr hyoid cartllage multilevel structure tensile strength

A Comparison of the bacterial Microflora between Coastal Sites in Qingdao, p.R. China and Loch Fyne, Scotland

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Journal of Ocean University of Qingdao 2002年第2期1卷 148-152页

作者： MacInnes J. Robertson p.A.W. Austin b. Centre for Marine biodiversity and biotechnology CMbb Department of Biological Sciences Heriot-Watt UniversityCentre for Marine Biodiversity and Biotechnology CMBB Department of Biological Sciences Heriot-Watt UniversityCentre for Marine Biodiversity and Biotechnology CMBB Department of Biological Sciences Heriot-Watt University Riccarton Edinburgh EH14 4AS Scotland UKRiccarton Edinburgh EH14 4AS Scotland UKRiccarton Edinburgh EH14 4AS Scotland UK

Aerobic, heterotrophic bacteria, recovered from two sites located on the west coast of Scotland, were compared to cultures obtained in a similar way from industrial, aquacultural and clean sites in the vicinity of Qingdao, Shandong, p.R. China. Gram-negative bacterial cultures were examined by bIOLOG-GN, and the data analysed by the simple matching (S SM) and Jaccard coefficients (S J) and unweighted average linkage clustering using NTSys. The output revealed that 20% of the bacteria, namely, Acinetobacter johnsonii, Aquaspirillum dispar, pseudomonas spp. (two groups), Sphingobacterium sp., Vibrio sp., V. campbellii, V. mimicus and V. hollisae, were common between the two geographical locations. However, the study revealed shortcomings with the bIOLOG-GN system for the study of coastal Gram-negative bacteria.

关键词： bacteria marine environment biodiversity bIOLOG-GN

Enterocolic phlebitis:a rare cause of bowel ischemia and review of the literature

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Gastroenterology Report 2023年第1期11卷 24-31页

作者： Stefanie bowee Sophia b.Matter Heather Dawson Roman A.Inglin Department of General Surgery Spital InterlakenUnterseenSwitzerland Institute of pathology University of BernBernSwitzerland

Enterocolic phlebitis(Ep)is a rare cause of bowel ischemia due to isolated venulitis of the bowel wall and mesentery without arterial *** is often misdiagnosed as inﬂammatory bowel disease,carcinoma,or diverticulitis due to non-speciﬁc symptoms as well as non-speciﬁc clinical and radiologicalﬁ*** unresponsive to pharmacotherapy,surgical resection of the affected bowel appears to be the only successful therapy with a very low recurrence *** of Ep remains *** report a case of Ep with rare presentation in the left hemicolon and unusual histologicalﬁndings emphasizing the heterogeneity of this cause of enterocolic *** review and comparison of the three enti-ties—Ep,mesenteric inﬂammatory veno-occlusive disease(MIVOD),and idiopathic myointimal hyperplasia of mesenteric veins(IMHMV),all describing patterns of bowel ischemia due to isolated pathology of mesenteric veins—reveal that the current terminology is *** and MIVOD are very similar and may be considered the same ***,though,differs in localization,symptom duration,and histologicalﬁndings but also shares features with Ep and *** studies and harmonized terminology are inevitable for better understanding of the disease,prevention of unnecessary pharmacotherapy,and reduction in time to diagnosis.

关键词： phlebitis acute abdomen mesenteric vascular occlusion mesenteric ischemia colectomy case report

Effect of debris on seasonal ice melt (2016−2018) on ponkar Glacier, Manang, Nepal

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Research in Cold and Arid Regions 2020年第5期12卷 261-271页

作者： Reeju Shrestha Rijan b.Kayastha Rakesh Kayastha Himalayan Cryosphere Climate and Disaster Research Center(HiCCDRC)Department of Environmental Science and EngineeringSchool of ScienceKathmandu UniversityDhulikhel 45200Nepal

Supraglacial debris is widely present on glaciers in alpine environments and its distribution greatly affects glacier *** present study aims to determine the effect of debris on glacier ice melt on ponkar Glacier,Manang District,*** estimated ice melt under various debris thickness using Energy balance(Eb)model and conductive heat flux methods,which are compared with in-situ *** stakes are installed on the glacier at different debris thickness of 11−40 *** data from March 2016 to May 2018 are obtained from the Automatic Weather Station(AWS)installed on the glacier surface at an elevation of 3,881 m *** the energy balance *** surface temperature and different debris depths are also measured on the *** calculated ablation rates from the conductive heat flux method are 0.9,1.62 and 0.41 cm/d on pre-monsoon,monsoon and post-monsoon,respectively,with mean debris thermal conductivity 1.04 W/(m∙K).The net radiation shows little variation between the seasons,while turbulent heat flux varies in the *** heat flux was found to be highest in post-monsoon season due to a larger temperature gradient between surface and air.

关键词： debris-covered glacier thermal conductivity energy flux ponkar Glacier ice melt Hindu-Kush Himalaya

Assessment of oxide nanoparticle stability in liquid phase transmission electron microscopy

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Nano Research 2019年第9期12卷 2355-2363页

作者： Mark J. Meijerink Krijn p. de Jong Jovana Zecevic Inorganic Chemistry and Catalysis Debye Institute of Nanomaterials ScienceUtrecht UniversityUniversiteitsweg 993584 CG UtrechtThe Netherlands

Studying liquid phase nanoscale dynamic processes of oxide nanoparticles is of considerable interest to a wide variety of *** developed liquid phase transmission electron microscopy(Lp-TEM)is a promising technique,but destabilization of oxides by solid-liquid?electron interactions remains an important *** this work we present a methodology to assess Lp-TEM oxide stability in an aqueous phase,by subjecti ng several oxides of tech no logical importa nee to a controlled electr on dose in *** show a correlati on based on the Gibbs free en ergy of oxide hydrati on that can be used to assess the stability of oxides and dem on strate the existenee of several remarkably stable oxides,with no observable structural changes after one hour of electron beam irradiation in *** such destabilization phenomena combined with the identification of stable oxides allows for designing Lp-TEM experiments free from adverse beam effects and thus in vestigati ons of numerous releva ntnano scale processes in water.

关键词： liquid phase transmission electron microscopy(Lp-TEM) transmission electron microscopy electron beam damage metal oxide nano materials oxide stability