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An Investigation of Freezing of Supercooled Water on Anti-Freeze Protein Modified Surfaces

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Journal of Bionic Engineering 2013年第2期10卷 139-147页

作者： Thibaut v J Charpentier Anne Neville paul Millner Rob Hewson Ardian Morina Institute of Engineering Thermofluids Surfaces and Interfaces (iETSI) Mechanical Engineering University of Leeds LS2 9JT Leeds UK

This work investigates how functionalization of aluminium surfaces with natural type III Anti-Freeze Protein （AFP） affects the mechanism of heterogeneous ice nucleation. First the bulk ice nucleation properties of distilled water and aqueous solution of AFP were evaluated by differential scanning calorimetry. Then the modified surface was characterized by Secondary Ions Mass Spectroscopy （SIMS）, Fourier Transform InfraRed （FTIR） spectroscopy and contact angle measurement. Freezing experiments were then conducted in which water droplets underwent a slow controlled cooling. This study shows that compared to uncoated aluminium, the anti-freeze proteins functionalized surfaces exhibit a higher and narrower range of freezing temperature. It was found that these proteins that keep living organisms from freezing in cold environment act in the opposite way once immobilized on surfaces by promoting ice nucleation. Some suggestions regarding the mechanism of action of the observed phenomena were proposed based on the Classical Nucleation Theory （CNT）.

关键词： anti-freeze protein surface functionalization ice nucleation temperature ice-like monolayer

DETERMINANTS OF STRUCTURE IN AQUATIC NON-PELAGIC PROTOZOAN COMMUNITIES

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Chinese Journal of Oceanology and Limnology 1993年第3期11卷 215-228页

作者： John Cairns Jr paul v.McCormick University Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.AUniversity Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.AUniversity Center for Environmental and Hazardous Materials Studies Virginia Polytechnic Institute and State University Blacksburg Virginia 24061 U.S.A

Although microbes have traditionally been used as models for testing ecological theory, research on the organization of these communities has largely been isolated from other areas of community ecology. Early studies indicated that microbial populations can form dynamic, interacting assemblages. Observations of distributional patterns suggest that certain deterministic forces regulate community structure. It appears that protozoans are tolerant of a wide range of environmental conditions although evidence for this is largely based on gross environmental analyses. Laboratory studies have suggested the importance of negative and positive biotic interactions in determining community membership, but little field evidence for this exists. The importance of transport processes in controlling community composition is being increasingly recognized. All three types of processes likely act to regulate the colonization and successional dynamics of these communities. A simple model is presented to promote the

关键词： determinants structure protozoan communities

A test on adverse selection of farmers in crop insurance:Results from Inner Mongolia,China

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Journal of Integrative Agriculture 2017年第2期16卷 478-485页

作者： ZHAO Yuan-feng CHAI Zhi-hui Michael S.Delgado paul v.Preckel College of Economics and Management Inner Mongolia Agricultural University Department of Agricultural Economics Purdue University

Adverse selection is an operating risk of crop insurance. Based on survey data on crop insurance collected by questionnaires in Inner Mongolia, China, the paper uses non-parametric analysis and econometric models to estimate the relationship between conditions for crop production and farmers＇ insurance decision in order to test the existence of farmers＇ adverse selection. The results show farmers＇ adverse selection does exist, but settling a claim by negotiation and premium subsidy from governments at all levels can defuse farmers＇ adverse selection under the current system of crop insurance. Risk regionalization, heterogeneous insurance contract and product innovation may decrease adverse selection to some extent.

关键词： crop insurance farmers adverse selection

Effect of processing routes on microstructure and mechanical properties of 2014 Al alloy processed by equal channel angular pressing

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Transactions of Nonferrous Metals Society of China 2010年第10期20卷 1822-1828页

作者： P.vENKATACHALAM S.RAMESH KUMAR B.RAvISANKAR v.THOMAS paul M.vIJAYALAKSHMI Department of Metallurgical and Materials Engineering National Institute of Technology Physical Metallurgy Division IGCAR

Al-Cu alloy was deformed through equal channel angular pressing(ECAP) by routes A,Ba,Bc and C up to 5 *** was done using a 90° die for three different conditions,namely 1) as received,2) solutionised at 768 K for 1 h and 3) solutionised at 768 K for 1 h + aged at 468 K for 5 *** microstructure,microhardness and tensile strength were studied for all the three conditions and four *** improvement in hardness(Hv 184 after five passes) and strength(602 MPa after three passes) was observed in solutionised and aged 2014 Al alloy deformed through route *** evolution was reasonably equiaxed in route Bc with aspect ratio of *** and aged 2014 Al alloy deformed through route Bc was identified to have better microstructure and mechanical property than the other processing routes and conditions.

关键词： ECAP processing route 2014 aluminium alloy

Ballistic impact response of flexible and rigid UHMWPE textile composites:Experiments and simulations

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Defence Technology（防务技术） 2023年第4期22卷 37-53页

作者： Hongxu Wang Dakshitha Weerasinghe paul J.Hazell Damith Mohotti Evgeny v.Morozov Juan P.Escobedo-Diaz School of Engineering and Information Technology The University of New South WalesCanberraACT2600Australia

This study elaborates on the effects of matrix rigidity on the high-velocity impact behaviour of UHMWPE textile composites using experimental and numerical *** composite samples were manufactured of a plain-weave fabric(comprising Spectra?1000 fibres)and four different matrix ***-velocity impact tests were conducted by launching a spherical steel projectile to strike on the prepared samples via a gas *** experimental results showed that the textile composites gradually changed from a membrane stretching mode to a plate bending mode as the matrix rigidity and thickness *** composites deformed in the membrane stretching mode had higher impact resistance and energy absorption capacity,and it was found that the average energy absorption per ply was much higher in this mode,although the number of broken yarns was smaller in the perforated ***,the flexible matrix composites always had higher perforation resistance but larger deformation than the rigid matrix counterparts in the tested thickness and velocity range.A novel numerical modelling approach with enhanced computational efficiency was proposed to simulate textile composites in mesoscale *** simulation results revealed that stress and strain development in the more rigid matrix composite was localised in the vicinity of the impact location,leading to larger local deformation and inferior perforation resistance.

关键词： Impact behaviour Textile composite UHMWPE fibre Energy absorption Finite element analysis

Genotypes and viral variants in chronic hepatitis B: A review of epidemiology and clinical relevance

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World Journal of Hepatology 2015年第3期7卷 289-303页

作者： Catherine MN Croagh paul v Desmond Sally J Bell Department of Gastroenterology St Vincent's Hospital

The Hepatitis B virus(HBv) has a worldwide distribu-tion and is endemic in many populations. It is constantly evolving and 10 genotypic strains have been identified with varying prevalences in different geographic regions. Numerous stable mutations in the core gene and in the su-rface gene of the HBv have also been identified in untreated HBv populations. The genotypes and viral variants have been associated with certain clinical featu-res of HBv related liver disease and Hepatocellu-lar carcinoma. For example Genotype C is associated withlater hepatitis B e antigen(HBe Ag) seroconversion, and more advanced liver disease. Genotype A is associated with a greater risk of progression to chronicity in adu-lt acqu-ired HBv infections. Genotype D is particu-larly associated with the precore mu-tation and HBe Ag negative chronic hepatitis B(CHB). The genotypes prevalent in parts of West Africa, Central and Sou-th America, E, F and H respectively, are less well stu-died. viral variants especially the Basal Core Promotor mutation is associated with increased risk of fibrosis and cancer of the liver. Althou-gh not cu-rrently part of rou-tine clinical care, evalu-ation of genotype and viral variants may provide u-sefu-l adju-nctive information in predicting risk abou-t liver related morbidity in patients with CHB.

关键词： Chronic hepatitis B Genotype Pre-core Basal core promotor Mutations

Phytochemical and anti-bacterial activity of epidermal glands extract of Christella parasitica (L.) H. Lev.

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Asian Pacific Journal of Tropical Biomedicine 2011年第1期1卷 8-11页

作者： paul Raj K Irudayaraj v Johnson M Patric Raja D Dartment of Plant Biology and Plant Biotechnology St.Xavier's College(Autonomous)

Objective:To study the morphology,biochemistry and bioactivity of the epidermal glands of the glandular morphotype of Christella parasitica(***)(L.) ***: Morphological studies on epidermal glands were earned out by using light microscope and scanning electron *** prepare the extract,the shade-dried fronds of glandular morphotype were soaked in *** antibacterial studies paper disc method was followed by using various pathogenic ***:Detailed micromorphological,phytochemical and bioactivity studies on a medicinal fern ***(L.) *** its inlraspecific variation in antibacterial *** presence or absence of the epidermal glands was the key factor for antibacterial activity in the morphovariants of this *** epidermal glands were orange-coloured,stalked and elongated ones of about 84.2μm×45μm,and distributed on the undersurface of cosla,coslules and veins in croziers,young and mature *** of glands varied from 15/cm on costa in mature leaves to 140/cm on costules in *** acetone extract of the glands showed antibacterial activities and also toxic effect against mosquito larvae and tadpoles of *** phytochemical analysis and HPLC studies of the gland extract showed the presence of various kinds of terpenoids,alkaloids,tannins,saponins and flavonoids in ***:The present study shows that epidermal glands of the glandular morphotype of C. parasitica(L.) *** several bioactive compounds and such rare moiphovariant should be conserved in *** next step is to isolate the pure compounds and to screen the bioactivity of individual compounds of the epidermal glands.

关键词： Epidermal glands Christella parasitica Bioactivity Phytochemical activity Anti-bacterial activity Morphology Biochemistry Glandular morphotype Light microscope Shade-dried frond Bioactive compound Morphovariant Preliminary phytochemical analysis Gland extract Flavonoid

Why ‘the uplift of the Tibetan Plateau’ is a myth

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National Science Review 2021年第1期8卷 156-174页

作者： Robert A.Spicer Tao Su paul J.valdes Alexander Farnsworth Fei-Xiang Wu Gongle Shi Teresa E.v.Spicer Zhekun Zhou CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Center of Plant Ecology Core Botanical GardensChinese Academy of Sciences School of Environment Earth and Ecosystem Sciences The Open University School of Geographical Sciences University of Bristol Key Laboratory of vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of Sciences State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of Sciences

The often-used phrase ‘the uplift of the Tibetan Plateau’ implies a flat-surfaced Tibet rose as a coherent entity, and that uplift was driven entirely by the collision and northward movement of India. Here, we argue that these are misconceptions derived in large part from simplistic geodynamic and climate modeling, as well as proxy misinterpretation. The growth of Tibet was a complex process involving mostly Mesozoic collisions of several Gondwanan terranes with Asia, thickening the crust and generating complex relief before the arrival of India. In this review, Earth system modeling, paleoaltimetry proxies and fossil finds contribute to a new synthetic view of the topographic evolution of Tibet. A notable feature overlooked in previous models of plateau formation was the persistence through much of the Cenozoic of a wide east–west orientated deep central valley, and the formation of a plateau occurred only in the late Neogene through compression and internal sedimentation.

关键词： Tibet paleoaltimetry paleogeography paleontology Himalaya

Hepatocellular carcinoma with child Pugh-A Cirrhosis treated with stereotactic body radiotherapy

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World Journal of Gastrointestinal Surgery 2017年第12期9卷 256-263页

作者： Shaakir Hasan Ngoc Thai Tadahiro Uemura vijay Kudithipudi paul Renz Stephen Abel Alexander v Kirichenko Division of Radiation Oncology Allegheny General Hospital Cancer Institute Division of Transplant Surgery Allegheny General Hospital Cancer Institute

AIM To evaluate the control, survival, and hepatic function for Child Pugh(CP)-A patients after Stereotactic body radiotherapy(SBRT) in hepatocellular carcinoma(HCC).METHODS From 2009 to 2016, 40 patients with Barcelona Liver Clinic(BCLC) stages 0-B HCC and CP-A cirrhosis completed liver SBRT. The mean prescription dose was 45 Gy(40 to 50 Gy in 4-5 fractions). Local relapse, defined as recurrence within the planning target volume was assessed with intravenous multiphase contrast computed tomography or magnetic resonance imaging every 4-6 mo after completion of SBRT. Progression of cirrhosis was evaluated by CP and Model for End Stage Liver Disease scores every 3-4 mo. Toxicities were graded per the Common Terminology Criteria for Adverse Events(v4.03). Median follow-up was 24 *** Forty-nine HCC lesions among 40 patients were analyzed in this IRB approved retrospective study. Median tumor diameter was 3.5 cm(1.5-8.9 cm). Six patients with tumors ≥ 5 cm completed planned selected transarterial chemoembolization(TACE) in combination with SBRT. Eight patients underwent orthotropic live transplant(OLT) with SBRT as a bridging treatment(median time to transplant was 12 mo, range 5 to 23 mo). The Pathologic complete response(PCR) rate in this group was 62.5%. The 2-year in-field local control was 98%(1 failure). Intrahepatic control was 82% and 62% at 1 and 2 years, respectively. Overall survival(OS) was 92% and 60% at 1 and 2 years, with a median survival of 41 mo per Kaplan Meier analysis. At 1 and 2 years, 71% and 61% of patients retained CPA status. Of the patients with intrahepatic failures, 58% developed progressive cirrhosis, compared to 27% with controlled disease(P = 0.06). Survival specific to hepatic failure was 92%, 81%, and 69% at 12, 18, and 24 mo. There was no grade 3 or higher toxicity. On univariate analysis, gross tumor volume(GTv) vival(P = 0.02), and tr

关键词： Stereotactic body radiotherapy Hepatocellular carcinoma Child-Pugh A Cirrhosis Hepatoma Local control Radiotherapy Radiation