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Der Nuklearmediziner 2014年第1期37卷 45-49页

作者： D. Hellwig Klinik für Nuklearmedizin Universitätsklinikum des Saarlandes Homburg

One of the most common causes of death worldwide is myocardial ischemia from a ruptured atherosclerotic plaque in a coronary artery. Not every plaque is at risk for rupture. Up to now there was no imaging modality to non-invasively identify a vulnerable plaque and to initiate treatment needed to prevent rupture or consecutive obstruction. f-18 sodium fluoride is a PET radiopharmaceutical for the imaging of bone formation. A while ago f-18 sodium fluoride was observed to accumulate in active calcifications of the aortic wall and of the coronary arteries. A recent study in patients shortly after myocardial infarction showed that ruptured plaques accumulate f-18 fluoride. In patients with stable angina, a close correlation was found between f-18 fluoride uptake and the signs of a plaque rupture as demonstrated by means of intra-coronary ultrasound. Based on histological analysis of specimens from carotid endarterectomy it was confirmed that f-18 fluoride accumulates in ruptured atherosclerotic tissue. With f-18 sodium fluoride PET/CT, for the first time a non-invasive method for the imaging of incipient plaque rupture is clinically feasible. Especially in acute coronary syndromes, maybe also in patients with stable angina, additional information guiding therapy is expected from this new indication of f-18 sodium fluoride PET/CT.

关键词： arteriosklerotischer Plaque f 18 Natriumfluorid PET/CT atherosclerotic plaque f 18 sodium fluoride PET/CT

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Cluster Analysis of Diffusion Tensor fields with Application to the Segmentation of the Corpus Callosum

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Procedia Computer Science 2016年 90卷 15-21页

作者： Safa Elsheikh Andrew fish Roma Chakrabarti Diwei Zhou School of Computing Engineering and Mathematics University of Brighton Brighton UK Department of Mathematical Sciences Loughborough University Loughborough UK

Accurate segmentation of the Corpus Callosum (CC) is an important aspect of clinical medicine and is used in the diagnosis of various brain disorders. In this paper, we propose an automated method for two and three dimensional segmentation of the CC using diffusion tensor imaging. It has been demonstrated that Hartigan's K-means is more efficient than the traditional Lloyd algorithm for clustering. We adapt Hartigan's K-means to be applicable for use with the metrics that have a f -mean (e.g. Cholesky, root Euclidean and log Euclidean). Then we applied the adapted Hartigan's K-means, using Euclidean, Cholesky, root Euclidean and log Euclidean metrics along with Procrustes and Riemannian metrics (which need numerical solutions for mean computation), to diffusion tensor images of the brain to provide a segmentation of the CC. The log Euclidean and Riemannian metrics provide more accurate segmentations of the CC than the other metrics as they present the least variation of the shape and size of the tensors in the CC for 2D segmentation. They also yield a full shape of the splenium for the 3D segmentation.

关键词： Corpus Callosum Hartigan's K-means f -mean Cholesky Procrustes Riemannian

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甲酰基肽受体1对BV-2细胞迁移的影响及机制的体外研究

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第三军医大学学报 2016年第1期38卷 44-49页

作者：薛鑫陈星星王冠郭乔楠刘明永赵建华第三军医大学大坪医院野战外科研究所脊柱外科重庆400042 第三军医大学新桥医院病理科重庆400037

目的探讨甲酰基肽受体1(formyl peptide receptor 1,fPR1)对BV-2细胞迁移的影响及潜在机制。方法免疫荧光染色检测BV-2细胞fPR1的表达,Transwell小室实验分别检测浓度为1、10、50、100、500 nmol/L的fPR1特异性激动剂(formylmethionyl-leucyl-phenylalanine,f MLP)对细胞迁移的影响,划痕实验及Transwell小室实验验证f MLP促进细胞迁移的作用可以被fPR1特异性阻断剂BocMLf所抑制。Western blot检测激动剂组、阻断剂组和阻断剂+激动剂组BV-2细胞经干预后其fPR1蛋白和磷酸化细胞外信号调节激酶(phospho-extracellular regulate kinase,p-ERK)蛋白表达量的变化。结果经免疫荧光染色结果显示,BV-2细胞表达fPR1,主要位于细胞膜表面。随着f MLP浓度的升高,Transwell迁移实验结果显示BV-2细胞的迁移能力明显增加(P<0.05),呈现出明显的剂量依赖性。100 nmol/L及500 nmol/L激动剂组效果最明显,f MLP促进BV-2细胞迁移的最适浓度为100 nmol/L。划痕及Transwell小室实验结果显示5μmol/L的Boc-MLf可显著阻断上述现象(P<0.05)。f MLP可以上调BV-2细胞中fPR1的表达(P<0.05),并且显著活化胞内ERK信号通路,上调p-ERK蛋白的表达水平(P<0.05),Boc-MLf又可显著抑制上述改变(P<0.05)。结论 BV-2细胞表达fPR1,且fPR1在促进BV-2细胞迁移中具有重要作用。

关键词： fPR1 f MLP Boc-MLf 细胞迁移小胶质细胞

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United States agricultural stakeholder views and decisions on climate change

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WILEY INTERDISCIPLINARY REVIEWS-CLIMATE CHANGE 2017年第5期8卷 e469页

作者： Chatrchyan, Allison M. Erlebacher, Rachel C. Chaopricha, Nina T. Chan, Joana Tobin, Daniel Allred, Shorna B. Cornell Univ Cornell Inst Climate Smart Solut Ithaca NY 14850 USA Penn State Univ Dept Agr Econ Sociol & Educ University Pk PA 16802 USA

Climate change poses unprecedented challenges to agricultural production globally and in the United States;it is both vulnerable to the impacts of a changing climate and a contributor to greenhouse gas emissions. Because farmers need to quickly adapt to reduce their risks and emissions, there is a pressing need to better understand the process by which they make decisions. This complex decision-making process includes many factors, such as farmers' beliefs;knowledge and capacity to make changes;the information they receive from Extension, industry, and social networks (e.g., family and peers);economics and regulations;and farm-scale and environmental issues (including personal experience with extreme weather). This study assesses the published literature on U.S. agricultural stakeholder views and decisions on climate change, focusing on farmers and ranchers from different regions. We identify key themes that emerge from the literature on how stakeholder views about extreme weather and climate change relate to decisions about adaptation and mitigation practices. This review finds that although the majority of U.S. farmers believe the climate is changing, many remain skeptical of the issue and uncertain about the anthropogenic causes of climate change. farmers' climate change mitigation and adaptation decisions also vary widely and are often correlated with belief or other factors such as personal experience with extreme weather, costs of change, or fear of regulation. We conclude with the implications of the research, including the importance of understanding farmers' view and actions and issue framing, and implications for researchers, Extension and policy makers, both nationally and globally. (c) 2017 Wiley Periodicals, Inc.

关键词： f

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La Unión Europea y su problemática de integración

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Economía Informa 2017年 403卷 4-20页

作者： Santiaga Ánima Puentes

La Unión Europea ha enfrentado en los últimos años serios problemas que han puesto en duda su viabilidad, frente a esa situación se plantea en este trabajo cuáles serían las posibles vías por las cuales los países integrantes de la Unión pueden superar las dificultades de la integración. Europa se ha visto cimbrada por la crisis global y ha mostrado su vulnerabilidad frente a embates externos de carácter financiero; en ese sentido, la Unión Europea no se ha visto fortalecida como era el objetivo de su creación. Los indicadores económicos han mostrado que los países de la Unión Europea están enfrentando fluctuaciones en su actividad económica a partir de la recesión de 2009, obligando a responder en un primer momento con políticas expansivas de la demanda agregada vía aumento del déficit público y de los niveles de endeudamiento, y en un segundo momento con políticas de ajuste y reducción del gasto. El contexto de crisis global en el cual la Unión Europea es un protagonista central la obliga a tener una mayor participación económica y social. El mayor reto que tiene es resolver sus problemas internos, una vez que lo logre podrá actuar en bloque frente a problemas provenientes de fuera de la zona europea, sino lo resuelven, se acrecentaran los conflicto económicos y sociales, mismos que pueden complicar más el escenario actual y retardar el proceso de integración europea. The European Union has faced in recent years serious problems that have called into question its viability, considering these facts, this work shares possible routes by which members of the Union can overcome the difficulties of the integration process. Europe has been shaken by the global crisis and has shown its vulnerability to external financial shocks; in this regard, the European Union has not been strengthened as it was intended with its creation. The economic indicators have shown that the countries of the European Union are facing constant fluctuations in their economic activity since the re

关键词： Economía internacional Integración económica Politica comercial International Economics Economic Integration Trade Negotiations f f02 f13

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Recombinant baculoviruses expressing f proteins in combination with VISA molecule confer protection against respiratory syncytial virus infection

Recombinant baculoviruses expressing F proteins in combinati...

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第十一届全国病毒学学术研讨会暨第六届武汉现代病毒学国际研讨会

作者： Yuan Zhang Lei Qiao Yiluo Tan Zishu Pan

Human respiratory syncytial virus(RSV),a negative-strand,non-segmented RNA virus,is the primary cause of viral lower respiratory tract illness in infancy and early childhood *** extensive efforts,highly effective treatments for RSV disease and a licensed vaccine to prevent this disease are not *** has been exploited for use as a novel vaccine vector.

关键词： Baculovirus Respiratory syncytial virus f protein Vaccine VISA

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Effects of sodium hypochlorite on structural/surface characteristics, filtration performance and fouling behaviors of PVDf membranes

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Journal of Membrane Science 2016年 519卷 22-31页

作者： fei Gao Jie Wang Hongwei Zhang Yang Zhang Mingqi April Hang School of Environmental Science and Engineering Tianjin University Tianjin 300072 China School of Environmental and Chemical Engineering State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Polytechnic University Tianjin 300387 China East Carolina University College of Allied Health Department of Audiology 3310 Health Sciences Building Health Science Dr Greenville NC 27858 United States

Sodium hypochlorite (NaClO) is a common chemical cleaning agent in water treatment due to its effective removal of irreversible pollutants that cannot be removed by physical cleaning. In this research, PVDf ultrafiltration (Uf) membranes were exposed to NaClO for 120–960 h, and then the structural/surface characteristics of the control and exposed membranes were compared. Results showed that different exposure doses lead to variations in PVDf membrane structural/surface characteristics according to different mechanisms and further influence the permeability and fouling behaviors of PVDf membranes during ultrafiltration (Uf) processes. Reversible fouling was the most common fouling behavior of membranes and exposure to NaClO resulted in higher degree of irreversible fouling. The irreversible flux decline of the membranes could not only caused by physically irremovable fouling but also irreversible compaction of the membranes due to the formation of macro-voids in the membrane skin layer. The changes in membrane mechanical properties caused a sharp increase in the inherent membrane resistance (R m ) which was generally considered as a constant. ‘Dynamic resistance mechanism’ could be proposed based on the impact of different NaClO exposure doses on the total membrane resistance (R t ), which is the sum of the changes in R m and the variation of fouling resistance (R f ) resulted from the changes in surface characteristics of the membranes. According to this concept, the filtration operating conditions and cleaning processes could be optimized in water treatment.

关键词： PVDf polyvinylidene fluoride Uf ultrafiltration ATR-fTIR attenuated total reflectance-fourier transform infrared PEG polyethylene glycol PVP polyvinyl pyrrolidone NOM natural organic matter HA humic acids BSA bovine albumin serum DOC dissolved organic carbon DMA dynamical mechanical analysis TGA thermogravimetric analysis TMP trans-membrane pressure Tf total fouling If irreversible fouling Rf reversible fouling R m inherent membrane resistance R f fouling resistance Sodium hypochlorite PVDf hollow fiber membrane Mechanical and thermal stability Cleaning fouling mechanisms

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Two-Dimensional fluorinated Graphene: Synthesis, Structures, Properties and Applications

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ADVANCED SCIENCE 2016年第7期3卷 1500413页

作者： feng, Wei Long, Peng feng, Yiyu Li, Yu Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Collaborat Innovat Ctr Chem Sci & Engn Tianjin Tianjin 300072 Peoples R China Minist Educ Key Lab Adv Ceram & Machining Technol Tianjin 300072 Peoples R China Tianjin Key Lab Composite & Funct Mat Tianjin 300072 Peoples R China

fluorinated graphene, an up-rising member of the graphene family, combines a two-dimensional layer-structure, a wide bandgap, and high stability and attracts significant attention because of its unique nanostructure and carbon-fluorine bonds. Here, we give an extensive review of recent progress on synthetic methods and C-f bonding;additionally, we present the optical, electrical and electronic properties of fluorinated graphene and its electrochemical/biological applications. fluorinated graphene exhibits various types of C-f bonds (covalent, semi-ionic, and ionic bonds), tunable f/C ratios, and different configurations controlled by synthetic methods including direct fluorination and exfoliation methods. The relationship between the types/amounts of C-f bonds and specific properties, such as opened bandgap, high thermal and chemical stability, dispersibility, semiconducting/insulating nature, magnetic, self-lubricating and mechanical properties and thermal conductivity, is discussed comprehensively. By optimizing the C-f bonding character and f/C ratios, fluorinated graphene can be utilized for energy conversion and storage devices, bioapplications, electrochemical sensors and amphiphobicity. Based on current progress, we propose potential problems of fluorinated graphene as well as the future challenge on the synthetic methods and C-f bonding character. This review will provide guidance for controlling C-f bonds, developing fluorine-related effects and promoting the application of fluorinated graphene.

关键词： C-f bonds f C ratio fluorinated graphene fluorographene

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Using Lif crystals for high-performance neutron imaging with micron-scale resolution

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High Power Laser Science and Engineering 2015年第4期3卷 1-9页

作者： A.faenov M.Matsubayashi T.Pikuz Y.fukuda M.Kando R.Yasuda H.Iikura T.Nojima T.Sakai M.Shiozawa R.Kodama Y.Kato Institute for Academic Initiatives Suita Osaka University Joint Institute for High Temperatures Russian Academy of Sciences Quantum Beam Science Center Japan Atomic Energy Agency PPC and Graduate School of Engineering Suita Osaka University Nippon SOKEN Inc. The Graduate School for the Creation of New Photonics Industries

This paper describes an overview of our recent discovery – clear demonstration that Li f crystals can be efficiently used as a high-performance neutron imaging detector based on optically stimulated luminescence of color centers generated by neutron irradiation. It is shown that the neutron images we have obtained are almost free from granular noise, have a spatial resolution of～5.4 μm and a linear response with a dynamic range of at least 103. The high contrast and good sensitivity of Li f crystals allow us to distinguish two holes with less than 2% transmittance difference. We propose to use such detectors in areas where high spatial resolution with high image gradation resolution is needed, including diagnostics of different plasma sources such as laser and z-pinch produced plasmas.

关键词： color centers Li f crystals neutron imaging neutrons plasma diagnostics

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C_f/ZrC-SiC复合材料抗氧化性能及机理分析

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济南大学学报（自然科学版） 2014年第2期28卷 123-126页

作者：马妍王英姿李庆刚王志史国普吴超济南大学材料科学与工程学院山东济南250022 济南大学山东省建筑材料制备与测试技术重点实验室山东济南250022

采用有机前驱体转化法制备C f/ZrC-SiC复合材料,探讨其抗氧化性能及机理,研究界面、氧化时间及氧化温度对材料抗氧化性能的影响。结果表明,有PyC沉积层的复合材料的抗氧化性能最好,纤维表面的玻璃相明显较多,能更好地保护纤维不被氧化;... 详细信息

采用有机前驱体转化法制备C f/ZrC-SiC复合材料,探讨其抗氧化性能及机理,研究界面、氧化时间及氧化温度对材料抗氧化性能的影响。结果表明,有PyC沉积层的复合材料的抗氧化性能最好,纤维表面的玻璃相明显较多,能更好地保护纤维不被氧化;随着氧化时间(10 min、15 min和30 min)和氧化温度(1 500℃、1 600℃和1 700℃)的增加,玻璃相逐渐增加,材料表面被氧化形成的ZrO2和SiO2覆盖,能阻止外部氧的进入,提高材料的抗氧化性能。

关键词： C f ZrC-SiC复合材料抗氧化性能机理分析

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