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Improved Hepascore in hepatitis C predicts reversal in risk of adverse outcome

World Journal of Hepatology 2017年第19期9卷 850-856页

作者： Angus W jeffrey Yi Huang W Bastiaan de Boer Leon A Adams Gerry MacQuillan David Speers John Joseph Gary P jeffrey School of Medicine University of Notre Dame School of Medicine and Pharmacology University of Western Australia department of Hepatology Sir Charles Gairdner Hospital department of Anatomical Pathology Path West QEII Medical Centre department of Microbiology Path West QEII Medical Centre department of Biochemistry Path West QEII Medical Centre

AIM To establish if serial Hepascore tests(referred to as delta Hepascore) in those with chronic hepatitis C(CHC) correlate with the increase and/or decrease in risk of liver related *** Three hundred and forty-six CHC patients who had two Hepascore tests performed were studied. During 1944 patient years follow-up 28(8.1%) reached an endpoint. The Hepascore is a serum test that provides clinically useful data regarding the stage of liver fibrosis andsubsequent clinical outcomes in chronic liver *** Patients with a baseline Hepascore > 0.75 had a significantly increased rate of reaching a composite endpoint consisting of hepatocellular carcinoma, liver death, and/or decompensation(P 0.75, a subsequent improved Hepascore showed a significantly decreased risk for the composite endpoint(P = 0.004). There were no negative outcomes in those with a stable or improved delta Hepascore. The minimum time between tests that was found to give a statically significant result was in those greater than one year(P = 0.03).CONCLUSION In conclusion, Hepascore is an accurate predictor of liver related mortality and liver related morbidity in CHC patients. Of note, we have found that there is a decreased risk of mortality and morbidity in CHC patients when the patient has an improving delta Hepascore. Repeat Hepascore tests, when performed at a minimum one-year interval, may be of value in routine clinical practice to predict liver related clinical outcomes and to guide patient management.

关键词： Chronic Prognosis Direct acting antivirals Serum Hepatitis C

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密度泛函理论研究无水环境下铂基催化剂上氧还原反应活性位点和反应机制

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Chinese Journal of Catalysis 2022年第12期43卷 3126-3133页

作者：刘广东邓辉球 Greeley jeffrey 曾振华湖南大学物理与微电子科学学院中国湖南长沙410082 普渡大学化学工程学院美国

2050-2060年实现碳净零排放已经成为世界上很多国家的战略使命.为实现该目标,氢燃料电池将在汽车燃料方面发挥重要作用.虽然客运燃料电池电动汽车已经成功推出,但其广泛应用仍是一个挑战,主要是因为质子交换膜燃料电池的铂阴极氧还原反... 详细信息

2050-2060年实现碳净零排放已经成为世界上很多国家的战略使命.为实现该目标,氢燃料电池将在汽车燃料方面发挥重要作用.虽然客运燃料电池电动汽车已经成功推出,但其广泛应用仍是一个挑战,主要是因为质子交换膜燃料电池的铂阴极氧还原反应动力学过于缓慢.理论上,提高氢燃料电池的运行温度有助于改善氧还原反应动力学,例如低温质子交换膜燃料电池的工作温度在80℃,如果反应活性位点和反应机制不变,将操作温度提升到120℃就可以使反应速率提高一个数量级.但是在实际应用过程中,目前最先进的高温质子交换膜燃料电池的性能仍然低于低温质子交换膜燃料电池的性能.为了进一步提高高温质子交换膜燃料电池的性能,研究人员在优化质子交换膜、电解质、催化剂结构、纳米颗粒的稳定性等方面开展了大量的研究工作并取得了显著进展,但对活性位点和反应机制仍缺乏了解.虽然已知高温质子交换膜燃料电池中的铂催化剂在温度高于100℃的无水条件下的活性位点和氧还原机制可能与低温质子交换膜燃料电池的不同,但以往研究并没有从原子尺度上获得相关的认识.本文结合平整的Pt(111)表面上以及含有(110)和(100)型台阶的Pt(332)和Pt(322)台阶表面上的氧还原反应,采用密度泛函理论计算研究了无水条件下铂基催化剂的氧还原反应的活性位点和催化机理.结合反应自由能和表面相图,发现在典型的氧还原反应电位下,Pt(111),Pt(332)和Pt(322)表面上分别集聚0.25,0.2和0.4 ML的氧原子.与有水环境下Pt(111)平台面的氧还原反应不同,由于无水条件下平台面上O*的聚集,使得氧还原中间体的吸附减弱,过电势远大于实验值.此外氧的聚集会增加O_(2)的解离势垒,这些都表明平台面在无水环境下不是氧还原反应的活性位.虽然台阶边缘位置在有水环境下不是氧还原反应的活性位,但是理论计算表明,它们是无水环境下的活性位点.这是因为台阶边缘的存在能稳定O_(2)的吸附,促进O_(2)的解离势垒.独特O聚集构型的(110)型台阶边缘尤其如此:与0.25 ML O集聚的Pt(111)表面相比,O_(2)的吸附能增强了0.36 eV,O_(2)的解离势垒降低了0.32 eV,反应过电势为0.38 V.综上,本文研究为设计具有更高性能的高温质子交换膜燃料电池的氧还原催化剂提供了理论指导.

关键词：氧还原反应活性位无水环境高温质子交换膜燃料电池密度泛函理论

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Finite element analysis on the static and fatigue characteristics of composite multi-leaf spring

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第3期13卷 159-164页

作者： Joo-teck jeffrey KUEH Tarlochan FARIS department of Mechanical Engineering Universiti Tenaga Nasional

This paper investigated the static and fatigue behaviors of steel and composite multi-leaf spring using the ANSYS V12 software. The dimensions of an existing conventional leaf spring of a light commercial vehicle were used. The same dimensions were used to design composite multi-leaf spring for the two materials, E-glass fiber/epoxy and E-glass fiber/vinyl ester, which are of great interest to the transportation industry. Main consideration was given to the effects of material composition and its fiber orientation on the static and fatigue behaviors of leaf spring. The design constraints were bending stresses, deflection and fatigue life. Compared to the steel leaf spring, the designed composite spring has much lower bending stresses and deflections and higher fatigue life cycles.

关键词：叶春天 Composites 有限元素应力偏转疲劳

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Ranking grey numbers based on dominance grey degrees

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Journal of Systems Engineering and Electronics 2014年第4期25卷 618-626页

作者： Yong Liu jeffrey Forrest Naiming Xie College of Economics and Management Nanjing University of Aeronautics and Astronautics School of Business Jiangnan University Mathematics department Slippery Rock University of USA

With respect to the decision making problems where a lot of fuzzy and grey information always exists in the real-life decision making information system methods as fuzzy mathematics, it is difficult for such uncertainty probability, and interval numbers to deal with. To this end, based on the thought and method of grey numbers, grey degrees and interval numbers, the concept of dominance grey degree is defined. And then a method of ranking interval grey numbers based on the dominance grey degree is proposed. After discussing the relevant properties, the paper finally uses an example to demonstrate the effectiveness and applicability of the model. The result shows that the proposed model can more accurately describe uncertainty decision making problems, and realize the total ordering process for multiple-attribute decision-making problems.

关键词： grey information dominance grey degree intervalgrey number total ordering.

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Bioinspired Dry Adhesive Materials and Their Application in Robotics： A Review

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Journal of Bionic Engineering 2016年第2期13卷 181-199页

作者： Yasong Li jeffrey Krahn Carlo Menon MENRVA Research Group School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC V5A 1S6 Canada

Dry adhesives inspired from climbing animals, such as geckos and spiders, rely on van der Waals forces to attach to the opposing surface. Biological fibrillar dry adhesives have a hierarchical structure closely resembling a tree： the surface of the skin on the animal＇s feet is covered in arrays of slender micro-fibrils, each of which supports arrays of fibrils in submicron dimensions. These nano-meter size fibrils can conform closely to the opposing surfaces to induce van der Waals interaction. Bioinspired dry adhesives have been developed in research laboratories for more than a decade. To mimic the biological fibrillar adhesives, fibrillar structures have been prepared using a variety of materials and geometrical arrangements. In this review article, the mechanism and selected fabrication methods of fibrillar adhesives are summarized for future reference in adhesive development. Robotic applications of these bioinspired adhesives are also introduced in this article. Various successful appli- cations of bioinspired fibrillar adhesives can shed light on developing smart adhesives for use in automation.

关键词： bioinspired gecko adhesive van der Waals forces biomimetic climbing robot bioinspired tape

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Fabrication and Testing of Self Cleaning Dry Adhesives Utilizing Hydrophobicity Gradient

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Journal of Bionic Engineering 2015年第2期12卷 270-275页

作者： Enrico Bovcro jeffrey Krahn Carlo Menon MENRVA Lab School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC Canada V5A 1S6

In this paper we present a method to create a hydrophobicity gradient on the surface of a Polydimethylsiloxane （PDMS） dry adhesive. The method consists of the partial silanization of the surface of the dry adhesive by Chemical Vapour deposition （CVD） of octadecyltrichlorosilane （OTS）. The partial silanization of the surface of the sample results in a hydrophobic to hy- drophilic gradient across the surface of the dry adhesive. The resulting change in hydrophobicity across the surface of the dry adhesive results in the uphill motion of a droplet of water, which appears to be directly proportional to the area of contact between the droplet and the adhesive. Normal adhesion testing is performed to quantify the effect of the hydrophobic gradient across the surface of the sample. While a variation in adhesion are only minimally affected by the silanization, and the motion strength across the sample is measured, the adhesive properties of the droplet of water doesn＇t cause any loss of adhesion.

关键词： dry adhesion self cleaning hydrophobic silanization polymers PDMS

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A zoological perspective on payments for ecosystem services

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Integrative Zoology 2007年第2期2卷 68-78页

作者： jeffrey A.McNEELY IUCN–The World Conservation Union GlandSwitzerland

The concept of payments for ecosystem services is being developed as an important means of providing a more diverse flow of benefits to people living in and around habitats valuable for *** Kyoto Protocol,under the United Nations Framework Convention on Climate Change,includes a Clean development Mechanism to provide for payments for certain forms of carbon sequestration that may benefit animal species(at least as an incidental benefit).Other market-based approaches for paying for carbon sequestration services outside the Kyoto framework are being promoted in various parts of the *** common form of payment for ecosystem services is compensating upstream landowners for managing their land in ways that maintain downstream water quality;this can include habitat management that benefits wild animal *** biodiversity itself is difficult to value,it can be linked to other markets,such as certification in the case of sustainably-produced forest *** paper expands on some of the markets for ecosystem services that also benefit wildlife,identifies relevant sources of information,and highlights some of the initiatives linking such markets to poverty *** markets work for ecosystem services requires an appropriate policy framework,government support,operational institutional support,and innovation at scales from the site level to the national *** have much to contribute to all of these steps.

关键词： biodiversity carbon trading ecosystem services payments watersheds

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“世界经济与中国2022:聚焦全球经济金融体系的未来”国际观点荟萃

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国际金融研究 2022年第1期 7-12页

作者： Joseph Stiglitz jeffrey Sachs 哥伦比亚大学

回顾2021年,新冠肺炎疫情仍未得到有效控制,发达经济体货币政策转向导致跨境资本流动波动性增强,国际金融市场风险增大,全球价值链面临重塑,各经济体复苏仍面临诸多不确定因素。为促进对国际及国内经济金融形势和重大经济金融热点问题... 详细信息

回顾2021年,新冠肺炎疫情仍未得到有效控制,发达经济体货币政策转向导致跨境资本流动波动性增强,国际金融市场风险增大,全球价值链面临重塑,各经济体复苏仍面临诸多不确定因素。为促进对国际及国内经济金融形势和重大经济金融热点问题的探讨,中国国际金融学会举办了以"世界经济与中国2022:聚焦全球经济金融体系的未来"为主题的学术年会,邀请众多国内外知名专家学者共同探讨后疫情时代全球经济复苏面临的新挑战,展望未来经济金融发展新趋势和新变化。本刊从国际嘉宾演讲中择发有代表性的演讲,分别从新冠肺炎疫情冲击及全球政治经济格局重塑视角展望全球与中国经济金融形势,希望以此推动经济金融相关问题的学术研究。

关键词：新冠肺炎疫情气候风险绿色增长国际合作

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Using economic instruments to overcome obstacles to in situ conservation of biodiversity

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Integrative Zoology 2006年第1期1卷 25-31页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

The leading direct cause of the loss of biodiversity is habitat alteration and *** we are to address this cause directly,we need to find ways of changing the behavior of rural *** has shown that this is done most effectively through the use of economic instruments,ranging from taxes that discourage over-exploitation,to direct payments for conservation activities carried out by rural land-owners or those occupying the *** many parts of the world,governments provide incentives such as tax breaks to private *** countries recognize specific use rights on particular parts of the land,enabling the land-owners to earn appropriate *** many protected areas have resident human populations,it is especially important that they be encouraged to contribute to the objectives of the protected area,and economic incentives offer an important way of doing so;they might,for example,be given employment in the protected area or in associated tourism *** payments to farmers for conserving watersheds is becoming increasingly popular,in both developed and developing *** conservation will require both removing perverse subsidies and developing a wide range of approaches for rewarding land-owners for biodiversity conservation activities.

关键词： ecosystem services incentives indigenous peoples protected areas resource rights

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Systems or species? Approaches to conservation for the 21st century

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Integrative Zoology 2006年第2期1卷 86-95页

作者： jeffrey A.McNEELY IUCN-The World Conservation Union GlandSwitzerland

One of the hot debates in the conservation community is whether to focus on individual species(for example,through species recovery plans,or lists of threatened species)or on systems approaches(such as the ecosystem approach advocated by the Convention on Biological Diversity).This paper will discuss some of the various options,before reaching a conclusion that both approaches are valid and mutually reinforcing,and that the dichotomy is a false *** more importantly,no conservation investment is likely to be effective if economic,social,and political factors are driving in the opposite ***,we need multiple approaches that build a stronger political constituency,new ways of providing knowledge for decisions,better ways of mobilizing information and dynamic approaches that enable us to adapt to changing conditions,and new ways to generate funding for conservation.

关键词： biodiversity conservation ecosystem approach protected areas species

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