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Magnetron co-sputtering synthesis and nanoindentation studies of nanocrystalline(TiZrHf)_(x)(NbTa)_(1–x)high-entropy al.oy thin films

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Nano Research 2022年第6期15卷 4873-4879页

作者： Changjun Cheng Xiaofu Zhang michel J.R.Haché Yu Zou department of Materials Science and engineering University of TorontoTorontoOntario M5S 3E4Canada State Key laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology and Center for Excellence in Superconducting ElectronicsChinese Academy of Sciences(CAS)Shanghai 200050China

Refractory high-entropy al.oys(HeAs)possess many useful properties such as high strength and high-temperature *** far,most studies on refractory HeAs have been limited to a few well-known compositions and on their coarse-grain bulk *** we fabricate nanocrystalline(TiZrHf)_(x)(NbTa)_(1−x)HeA thin films with a large range of compositions(x=0.07–0.90)by the direct current(DC)magnetron co-sputtering technique and measure their mechanical properties using the nanoindentation *** the as-deposited HeA thin films show a solid-solution body-centered cubic(bcc)*** the compositional ratio(x)increases,the elastic modulus decreases from 153 to 123 GPa,fol.owing the trend of the rule of *** x increases,the hardness first decreases from 6.5 GPa(x=0.07)to the lowest value(4.6 GPa,x=0.48)and then increases to the highest value(7.1 GPa,x=0.90),showing a concave *** change in hardness might be attributed to the combinational influence caused by the atomic size and modulus effects,as well as the texture *** authors al.o propose a few open questions for future studies on this and related HeA systems.

关键词： high-entropy al.oys nanocrystalline al.oys refractory metals thin films magnetron co-sputtering nanoindentation

The Asian lineage of Zika Virus: Transmission and evolution in Asia and the Americas

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Virologica Sinica 2019年第1期34卷 1-8页

作者： Tao Hu Juan li Michael J.Carr Sebastián Duchêne Weifeng Shi Key laboratory of etiology and epidemiology of emerging Infectious Diseases in Universities of Shandong Taishan Medical College Global Station for Zoonosis control Global Institution for Collaborative Research and Education (GI-CoRE)Hokkaido University National Virus Reference laboratory School of MedicineUniversity College Dublin department of Biochemistry and Molecular Biology Bio21 Molecular Science and Biotechnology InstituteUniversity of Melbourne

Since first isolation in 1947 from the Zika forest in Uganda, Zika virus(ZIKV) has been principally known as a benign agent associated with sporadic human infections in a restricted number of African countries. However, during 2015–2016,an Asian lineage of ZIKV caused an unprecedentedly large outbreak in the Americas and sizeable numbers of exported cases across the globe. In this review, we critically appraise the recent advances in molecular epidemiological studies of ZIKV performed to date, and we highlight the pivotal role played by genomic surveillance in elucidating the origins,dissemination and evolution of the Asian lineage of ZIKV in Asia and in the Americas.

关键词： Zika virus(ZIKV) Asian lineage Transmission evolution Re

Is platinum-loaded titania the best material for dye-sensitized hydrogen evolution under visible light?

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Chinese Journal.of Catalysis 2024年第8期63卷 124-132页

作者： Haruka Yamamoto langqiu Xiao Yugo Miseki Hiroto Ueki Megumi okazaki Kazuhiro Sayama Thomas e.Mal.ouk Kazuhiko Maeda department of Chemistry School of ScienceTokyo Institute of Technology2-12-1-NE-2 OokayamaMeguro-kuTokyo 152-8550Japan department of Chemistry University of Pennsylvania231 S.34th Street PhiladelphiaPA 19104United States Global Zero emission Research Center(GZR) National Institute of Advanced Industrial Science and Technology(AIST)West16-1OnogawaTsukubaIbaraki 305-8569Japan International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)TsukubaIbaraki 305-0044Japan Research Center for Autonomous Systems Materialogy(ASMat) Tokyo Institute of Technology4259 Nagatsuta-choMidori-kuYokohamaKanagawa 226-8501Japan

A dye-sensitized photocatalyst combining Pt-loaded Tio_(2)and Ru(Ⅱ)tris-diimine sensitizer(RuP)was constructed and its activity for photochemical hydrogen evolution was compared with that of Pt-intercalated HCa_(2)Nb_(3)o_(10)*** the sacrificial donor ethylenediaminetetraacetic acid(eDTA)disodium salt dihydrate was used,RuP/Pt/Tio_(2)showed higher activity than RuP/Pt/HCa_(2)Nb_(3)o_(10).In contrast,when NaI(a reversible electron donor)was used,RuP/Pt/Tio_(2)showed little activity due to back electron transfer to the electron acceptor(I3-),which was gener-ated as the oxidation product of I-.By modification with anionic polymers(sodium poly(styrenesul.onate)or sodium polymethacrylate)that could inhibit the scavenging of conduction band electrons by I3-,the H_(2)production activity from aqueous NaI was improved,but it did not exceed that of RuP/Pt/HCa_(2)Nb_(3)o_(10).Transient absorption measurements showed that the rate of semiconductor-to-dye back electron transfer was slower in the case of Tio_(2)than HCa_(2)Nb_(3)o_(10),but the electron transfer reaction to I3-was much *** results indicate that Pt/Tio_(2)is useful for reactions with sacrificial reductants(e.g.,eDTA),where the back electron transfer reaction to the more reducible product can be ***,more careful design of the catalyst will be nec-essary when a reversible electron donor is employed.

关键词： Artificial photosynthesis Solar fuel Water splitting Z-scheme

Pancreaticβ-cell dysfunction in type 2 diabetes:Implications of inflammation and oxidative stress

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World Journal.of Diabetes 2023年第3期14卷 130-146页

作者： Phiwayinkosi V Dludla Sihle e Mabhida Khanyisani Ziqubu Bongani B Nkambule Sithandiwe e Mazibuko-Mbeje Sidney Hanser Albert Kotze Basson Carmen Pheiffer Andre pascal Kengne Biomedical Research and Innovation Platform South African Medical Research CouncilCape Town 7505South Africa department of Biochemistry and Microbiology University of ZululandKwaDlangezwa 3880South Africa department of Biochemistry North-West UniversityMmabatho 2745South Africa School.of laboratory Medicine and Medical Sciences University of KwaZulu-NatalDurban 4000South Africa department of Physiology and environmental Health University of LimpopoSovenga 0727South Africa department of Medicine University of Cape TownCape Town 7500South Africa Non-communicable Diseases Research Unit South African Medical Research CouncilTygerberg 7505South Africa

Insulin resistance and pancreaticβ-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes(T2D).Beyond the detrimental effects of insulin resistance,inflammation and oxidative stress have emerged as critical features of T2D that defineβ-cell *** markers of inflammation such as C-reactive protein,tumor necrosis factor alpha,and interleukin-1βare consistently associated withβ-cell failure in preclinical models and in people with ***,important markers of oxidative stress,such as increased reactive oxygen species and depleted intracellular antioxidants,are consistent with pancreaticβ-cell damage in conditions of *** effects illustrate a pathological relationship between an abnormal inflammatory response and generation of oxidative stress during the progression of *** current review explores preclinical and clinical research on the pathological implications of inflammation and oxidative stress during the development ofβ-cell dysfunction in ***,important molecular mechanisms and relevant biomarkers involved in this process are discussed to divulge a pathological link between inflammation and oxidative stress duringβ-cell failure in *** the clinical relevance of the review,a systematic analysis of evidence from randomized controlled trials is covered,on the potential therapeutic effects of some commonly used antidiabetic agents in modulating inflammatory makers to improveβ-cell function.

关键词： Type 2 diabetes Insulin resistance β-cell dysfunction Inflammation oxidative stress

Acute calculous cholecystitis: Review of current best practices

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World Journal.of Gastrointestinal Surgery 2017年第5期9卷 118-126页

作者： Carlos Augusto Gomes Cleber Soares Junior Salomone Di Saveiro Massimo Sartelli michel denis Kelly Camila couto Gomes Felipe couto Gomes lívia Dornellas correa Camila Brandao Alves Samuel de Fádel Guimaraes Surgery depart-ment Hospital Universitário Therezinha de Jesus Faculdade de Ciências Médicas e da Saúde Juiz de Fora Trauma Surgery Unit Maggiore Hospital department of Surgery Macerata Hospital Acute Surgical Unit Canberra Hospital Surgery department Hospital Gover-nador Israel Pinheiro (HGIP IPSEMG) Internal Medicine Unit Hospital Universitário Therezinha de Jesus Faculdade de Ciências Médicas e da Saúde Juiz de Fora

Acute calculous cholecystitis(ACC) is the most frequent complication of cholelithiasis and represents one-third of all surgical emergency hospital admissions, many aspects of the disease are still a matter of debate. Knowledge of the current evidence may al.ow the surgical team to develop practical bedside decision-making strategies, aiming at a less demanding procedure and lower frequency of complications. In this regard, recommendations on the diagnosis supported by specific criteria and severity scores are being implemented, to prioritize patients eligible for urgency surgery. laparoscopic cholecystectomy is the best treatment for ACC and the procedure should ideally be performed within 72h. early surgery is associated with better results in comparison to delayed surgery. In addition, when to suspect associated common bile duct stones and how to treat them when found are still debated. The antimicrobial agents are indicated for high-risk patients and especially in the presence of gallbladder necrosis. The use of broad-spectrum antibiotics and in some cases with antifungal agents is related to better prognosis. Moreover, an emerging strategy of not converting to open, a difficult laparoscopic cholecystectomy and performing a subtotal cholecystectomy is recommended by adept surgical teams. Some authors support the use of percutaneous cholecystostomy as an alternative emergency treatment for acute Cholecystitis for patients with severe comorbidities.

关键词： Cholecystitis Cholelithiasis Biliary stones Cholecystectomy laparoscopy

Numerical simulations of water flow and contaminants transport near mining wastes disposed in a fractured rock mass

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International Journal.of Mining Science and Technology 2015年第1期25卷 37-45页

作者： Ben Abdelghani Farouk Aubertin michel Simon Richard Therrien René department of Civil engineering Institut Supérieur de la Construction et de l’Urbanisme Research Institute on Mines and the environment (RIMe) Polytechnique Montreal department of Geology and Geological engineering University Laval

A numerical tool, called Hydro-Geosphere, was used to simulate unsaturated water flow and contaminants migration around an open pit filled with mining wastes. Numerical simulations had been carried out to assess the influence of various factors on water flow and solute transport in and around the surface openings including recharge, properties of the waste material and presence of fractures in the surrounding rock mass. The effect of the regional hydraulic gradient was al.o investigated. The analyses were conducted by simulating various 2D cases using experimentally obtained material properties and controlled boundary conditions. The effects of the hydrogeological properties of the filling material(i.e., water retention curve and hydraulic conductivity function), fracture network characteristics and conductivity of the joints were assessed. The results illustrate that fractures control water flow and contaminants transport around the waste disposal area. A fracture network can desaturate the system and improve the regional gradient effect.

关键词： Hydro-GeosphereNumerical modellingUnsaturated water flowcontaminants transportTailingsWaste rocks

Attractors for a Three-Dimensional Thermo-Mechanical Model.of Shape Memory Al.oys

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Chinese Annals of Mathematics,Series B 2006年第6期27卷 683-700页

作者： Pierluigi collI michel FRMoND elisabetta RoCCA Ken SHIRAKAWA Dipartimento di Matematica "F. Casorati" Università degli Studi di Paviavia Ferrata 127100 PaviaItaly. laboratoire Central des Ponts et Chaussées 58 Boulevard Lefebvre75732 Paris Cedex 15France. Dipartimento di Matematica "F. enriques" Università degli Studi di Milanovia Saldini 5020133 MilanoItaly. department of Applied Mathematics Faculty of Engineering Kobe University 1-1 RokkodaiNadaKobe 657-8501Japan.

In this note, we consider a Fremond model.of shape memory al.oys. let us imagine a piece of a shape memory al.oy which is fixed on one part of its boundary, and assume that forcing terms, e.g., heat sources and external stress on the remaining part of its boundary, converge to some time-independent functions, in appropriate senses, as time goes to infinity. Under the above assumption, we shall discuss the asymptotic stability for the dynamical system from the viewpoint of the global attractor. More precisely, we generalize the paper dealing with the one-dimensional case. First, we show the existence of the global attractor for the limiting autonomous dynamical system; then we characterize the asymptotic stability for the non-autonomous case by the limiting global attractor.

关键词： Shape memory Thermomechanical model Parabolic system of partial differential equations Global attractor

estimation of radiation hazard indices from natural radioactivity of some rocks

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Nuclear Science and Techniques 2006年第2期17卷 118-122页

作者： A.ABBADY N.K.AHMeD A.M.el-ARABI R.michel A.H.el-KAMel A.G.e.ABBADY Physics department Faculty of Science Qena South Valley University Egypt Institute of the Radiation Protection and Radioecology Hannover University Germany Physics department Faculty of Science Assiut University Egypt

Different samples of igneous and metamorphic rocks from egypt and Germany have been considered to measure γ-ray activity concentrations due to naturally occurring, potentially hazardous radonuclides 226Ra, 232Th and 40K. The radiation hazard parameters including radiation equivalent activity, gamma-absorbed dose rate, and exter- nal and internal hazard indices have been estimated. The gamma-absorbed dose rates in air of rocks in egypt range from 4.2 to 128.5 nGy·h-1 with a mean value of 55.3 nGy·h-1. For igneous and metamorphic rocks from Germany, the values of absorbed dose rates fluctuate from 5.1 to 148.6 nGy·h-1, with a mean value of 60.9 nGy·h-1. Generally, it is found that the radiation hazard indices in common igneous rocks are distinctly higher in acidic than in ultrabasic rocks. The results are discussed and compared with the corresponding published data.

关键词：自然放射性岩石变质岩环境放射学

Finite-Size conformational Transitions: A Unifying concept Underlying Chromosome Dynamics

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communications in Theoretical Physics 2014年第10期61卷 607-616页

作者： Bertrand R.Caré pascal Carrivain Thierry Forné Jean-Marc Victor Annick lesne laboratoire de Physique Théorique de la Matière condensée CNRS UMR 7600UPMC University Paris 06F-75005ParisFrance CNRS GDR 3536 UPMC University Paris 06F-75005ParisFrance Institut de Génétique Humaine CNRS UPR 1142 MontpellierFrance Institut de Génétique Moléculaire de Montpellier CNRS UMR 5535University of MontpellierMontpellierFrance Kavli Institute for Theoretical Physics China CAS

Investigating average thermodynamic quantities is not sufficient to understand conformational transitions of a finite-size polymer. We propose that such transitions are better described in terms of the probability distribution of some finite-size order parameter, and the evolution of this distribution as a control parameter varies. We demonstrate this claim for the coil-globule transition of a linear polymer and its mapping onto a two-state model. In a biological context, polymer models delineate the physical constraints experienced by the genome at different levels of organization,from DNA to chromatin to chromosome. We apply our finite-size approach to the formation of plectonemes in a DNA segment submitted to an applied torque and the ensuing helix-coil transition that can be numerically observed, with a coexistence of the helix and coil states in a range of parameters. Polymer models are al.o essential to analyze recent in vivo experiments providing the frequency of pairwise contacts between genomic loci. The probability distribution of these contacts yields quantitative information on the conformational fluctuations of chromosome regions. The changes observed in the shape of the distribution when the cell type or the physiological conditions vary may reveal an epigenetic modulation of the conformational constraints experienced by the chromosomes.

关键词： coil-globule transition helix-coil transition chromosome conformational capture two-state model