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分子动力学模拟研究直链淀粉与α-亚油酸的包合行为

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中国粮油学报 2016年第4期31卷 35-40页

作者：冯涛王旭庄海宁 Feng Chen Bruce R Hamaker osvaldo Campanella 王凯上海应用技术学院香料香精技术与工程学院上海201418 上海市农业科学院食用菌研究所国家食用菌工程技术研究中心上海201403 美国普度大学食品系惠斯特勒碳水化合物研究中心美国印第安纳州479062009 云南中烟工业有限责任公司技术中心昆明650231

α-亚油酸和直链淀粉可以形成热力学稳定复合物。为了研究α-亚油酸影响直链淀粉构象的机理、复合物的构象趋势及复合作用过程中氢键的变化情况,在373 K条件下进行了长时间(500 ns)的全原子分子动力学模拟。模拟发现在有/无α-亚油酸存... 详细信息

α-亚油酸和直链淀粉可以形成热力学稳定复合物。为了研究α-亚油酸影响直链淀粉构象的机理、复合物的构象趋势及复合作用过程中氢键的变化情况,在373 K条件下进行了长时间(500 ns)的全原子分子动力学模拟。模拟发现在有/无α-亚油酸存在的情况下,在500 ns内都可以观察到大量有序到无序的构象转变,这表明直链淀粉和α-亚油酸之间结合作用微弱。原子均方根偏差(RMSD)、α-亚油酸与直链淀粉轴心间距、氢键增加都证明直链淀粉-α-亚油酸复合物的形成是热力学自发行为。

关键词：分子动力学模拟直链淀粉 α-亚油酸

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三聚体纳米颗粒自组装过程的分子动力学模拟

农业工程学报 2017年第3期33卷 300-306页

作者：冯涛王珂周进杰 Deepak Bhopatkar 陈枫 osvaldo Campanella Bruce R.Hamaker Marcelo Carignano 庄海宁上海应用技术学院香料香精技术与工程学院上海201418 普度大学食品科学系惠斯特勒碳水化合物研究中心西拉法耶特市479062009 普度大学信息技术中心罗森高级计算中心西拉法耶特市*** 卡塔尔环境与能源研究所上海市农业科学院食用菌研究所国家食用菌工程技术研究中心上海201403

为了更深入理解直链淀粉/β-乳球蛋白/α-亚油酸三元复合物体系自组装行为的机制,该研究借助Gromacs软件,采用分子动力学模拟对玉米直链淀粉、β-乳球蛋白、α-亚油酸三者在373 K温度下的结合过程进行研究。通过三元纳米粒子在500 ns内... 详细信息

为了更深入理解直链淀粉/β-乳球蛋白/α-亚油酸三元复合物体系自组装行为的机制,该研究借助Gromacs软件,采用分子动力学模拟对玉米直链淀粉、β-乳球蛋白、α-亚油酸三者在373 K温度下的结合过程进行研究。通过三元纳米粒子在500 ns内的自组装快照图,可以得出直链淀粉、α-亚油酸、β-乳球蛋白3种组分的结合顺序。通过三元纳米粒子的自由能曲面图,可知该三元纳米粒子的形成是热力学自发的过程。进一步对其水合半径及溶剂可接触表面积的分析表明,该三元复合物纳米颗粒溶解性良好。研究阐释了水溶性自组装纳米颗粒的形成机理,为纳米科学领域寻找合适的壁材提供了一种新的研究途径。

关键词：纳米颗粒分子动力学自组装直链淀粉 β-乳球蛋白 α-亚油酸

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转动翻卸车辆的解钩装置

国外铁道车辆 1991年第6期28卷 25-29页

作者： osvaldo F. Chierici 李渝生

本专利介绍单元列车转动翻卸车辆解钩装置的结构与动作及该装置的专利说明。

关键词：车辆解钩装置单元列车

Differential Effects of Voluntary Ethanol Consumption on Dopamine Output in the Nucleus Accumbens Shell of Roman High- and Low-Avoidance Rats: A Behavioral and Brain Microdialysis Study

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World Journal of Neuroscience 2014年第3期4卷 279-292页

作者： Maria G. Corda Giovanna Piras Maria A. Piludu osvaldo Giorgi Department of Life and Environmental Sciences Section of Pharmacological Pharmaceutical and Nutraceutical Sciences University of Cagliari Cagliari Italy

The Roman high(RHA) and low-Avoidance (RLA) rats were selectively bred for rapid vs poor acquisition of two-way active avoidance behavior. These lines differ in numerous behavioral traits, with RLA rats being more fearful/anxious than RHA rats, and the latter being novelty-seekers and showing larger intake of, and preference for, addictive substances including ethanol (ETH). Moreover, several differences in central dopaminergic, serotonergic, and GABAergic functions have been reported in these two lines. Since those neural systems are involved in the regulation of ETH consumption, it was considered of interest to investigate: 1) the differences in ETH intake and preference between RHA and RLA rats, 2) the effects of ETH on DA release in the shell of the nucleus accumbens (AcbSh) using brain microdialysis. ETH solutions of increasing concentrations (2% - 10%) were presented on alternate days in a free choice with water. To examine ETH intake and preference stability, animals were subsequently switched to daily presentations of 10% ETH for 10 consecutive days. RHA rats consumed significantly larger amounts of ETH and displayed higher ETH preference than did RLA rats throughout the acquisition and maintenance phases. Following chronic exposure to ETH the animals were habituated to a restricted access to ETH schedule (2% ETH, 2 h per day × 4 days) before surgical implantation of a dialysis probe in the AcbSh. Under these experimental conditions, voluntary ETH intake (2%, 1 h, p.o.) produced a significant increase in accumbal DA output in RHA rats but not in their RLA counterparts. Finally, the i.p. administration of ETH (0.25 g/kg) to na?ve Roman rats produced a significant increment in accumbal DA output only in RHA rats. These results indicate that the mesolimbic dopaminergic system of RHA rats is more responsive to the effects of ETH than that of RLA rats.

关键词： Roman High- and Low-Avoidance Rats Voluntary Ethanol Consumption Mesolimbic Dopaminergic System Nucleus Accumbens Shell Novelty-Seeking Behavior

Does Location or Sector Matters？ Analysis of Euro-Zone Energy Companies

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材料科学与工程（中英文A版） 2013年第8期3卷 584-589页

作者： Valdir de Jesus Lameira Roberto Guimaraes Pereir osvaldo Luis Goncalves Quelhas National Institute of Systems Engineering and Computer of Coimbra Portugal Fluminense Federal University Niteroi R J 24210-240 Brazilr

Failure Analysis of Austenitic Stainless Steel Implant Screws and Prospection of Chemical Composition Using Artificial Intelligence

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World Journal of Engineering and Technology 2022年第1期10卷 98-118页

作者： Alfonso Monzamodeth Román-Sedano Bernardo Campillo Fermín Castillo osvaldo Flores Facultad de Química Universidad Nacional Autónoma de México Ciudad de México México Instituto de Ciencias Físicas Universidad Nacional Autónoma de México Cuernavaca Morelos México

In this work, austenitic stainless steel screws employed in a locking compression plate for veterinarian use were investigated. These types of implants are widely utilized in bone fractures healing. Two surgical screws were extracted due to the observation of slight superficial red rust colorizing on one of the screw implants, visual evidence of probable screw rusting. From the same implant, another screw was extracted simultaneously without visual evidence of rusting. In order to characterize and analyze the different behavior of both screws, the chemical composition was characterized by atomic absorption and energy dispersive X-ray spectroscopy (EDS) coupled to a scanning electron microscope (SEM). Also, the screws were studied by metallography, optical microscopy (OM), Vickers microhardness tests, and SEM analysis. On the other hand, a prospection for alloy chemical composition limits of these types of implants was performed based on the Schaeffler-Delong diagram and the ASTM F-138 standard. To analyze the effect of the chemical composition, heat treatment, microstructure, pitting resistance equivalent number (PRE) and stacking fault energy (SFE), a genetic algorithm (GA) and an artificial neural network (ANN) were used. In accordance with the elemental analysis, the surgical screws do not fulfill the ranges of the chemical composition established by the ASTM F-138 standard. Furthermore, there were found differences between the microstructures of the screws. In regard to the prospection, the results of GA and ANN support the proposed chemical composition region on the Schaeffler-Delong diagram. The corrosion failure was associated with severe plastic deformation and the presence of precipitates. The proposal can minimize the cause of failures in these types of austenitic stainless steel implants.

关键词： Implant Screw Failure Analysis Genetic Algorithm Artificial Neural Network Austenitic Stainless Steel

Cirrus Clouds and Multiple Tropopause Events over Buenos Aires

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Atmospheric and Climate Sciences 2011年第3期1卷 113-119页

作者： Susan Gabriela Lakkis Mario Lavorato Pablo osvaldo Canziani Héctor Lacomi 不详

Lidar measurements of midlatitude cirrus clouds over Buenos Aires, collected between 2002 and 2003 are compared with multiple tropopauses (MT) retrieved from rawinsonde temperature retrievals. Results derived from the rawinsondes display MT events with an annual cycle which are fewest in March. Comparison with lidar observations shows that cirrus clouds are mostly located closely below the first tro-popause, but when cloud top is above the first tropopause, in 25% of cases, the cloud base is not above it, resulting in a cirrus cloud crossing the inter-tropopause region. Compared with the distribution of the whole population of midlatitude cirrus clouds, cross-tropopause cirrus clouds display a similar geometrical thick-ness as inter-tropopause cirrus clouds.

关键词： Multitropopause Events Cirrus Clouds Lidar

Root proliferation in native perennial grasses of arid Patagonia,Argentina

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Journal of Arid Land 2014年第2期6卷 195-204页

作者： Yanina A TORRES Carlos A BUSSO Oscar A MONTENEGRO Leticia ITHURRART Hugo D GIORGETT Gustavo RODRíGUEZ Diego BENTIVEGNA Roberto E BREVEDAN osvaldo A FERNáNDEZ María M MUJICA Sandra S BAIONI José ENTíO María N FIORETTI Guillermo TUCAT Agronomy Department National University of the South and CERZOS (CONICET) Experimental Farm EEA INTA Patagones Ministery of Agrarian Issues Faculty of Agrarian Sciences National University of La Plata

Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that （1） defoliation reduce net primary productivity, and root length density and weight in the native species, and （2） root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species （i.e., Aristida spegazzinfi, A. subulata and Sporobolus cryptandrus）. Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season （2008-2009）, cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid- and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den- sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

关键词： Aristida species competitive ability Pappophorum vaginatum Sporobolus cryptandrus warm-season perennial grasses

Peristomal variceal bleeding treated by coil embolization using a percutaneous transhepatic approach

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World Journal of Clinical Cases 2016年第1期4卷 25-29页

作者： Macello José Sampaio Maciel osvaldo Ignácio Pereira Joaquim Maurício Motta Leal Filho Enio Ziemiecki Junior Susyanne Lavor Cosme Moisés Amancio Souza Francisco Cesar Carnevale Radiology Department of Heart Institute Hospital das ClínicasFaculdade de Medicina da Universidade de São Paulo

Peristomal variceal bleeding due to portal hypertension is an entity that has rarely been reported with 3%-4% risk of death.A 68-year-old woman who had undergone a palliative colostomy(colorectal carcinoma) presented with a massive hemorrhage from the colostomy *** her oncological status with medial and right hepatic veins thrombosis due to liver metastasis invasion,an emergency transhepatic coil embolization was successfully *** treatment modality for these cases has not been *** transhepatic coil embolization of varices is a safe and effective choice in patients who present with life threatening bleeding and exhibit contraindications to transjugular intrahepatic portosystemic shunt.

关键词： Ectopic variceal bleeding Stomal bleeding Percutaneous transhepatic embolization Colostomy Cirrhosis Hemostasis