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Montezuma's revenge-the sequel: The one-hundred year anniversary of the first description of “post-infectious” irritable bowel syndrome

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World Journal of Gastroenterology 2018年第45期24卷 5076-5080页

作者： Mark S Riddle Patrick Connor Chad K porter Department of Preventive Medicine and Biostatistics Uniformed Services University Military Enteric Disease Group Department of Military Medicine Royal Centre for Defence Medicine Birmingham Research Park Department of Enteric Diseases Naval Medical Research Center

One-hundred years have passed since the original description of the commonly described phenomenon of persistent abdominal symptoms being triggered by an acute enteric infection. This first account was generated out of astute observations by Sir Arthur Hurst in World War I. Additional descriptions followed from military and non-military practitioners adding the evidence which has transitioned this recognized condition from association to causation. While mechanistic understanding is an area of active pursuit, this historical accounting of a centuries progress highlights important advances and contributions of military medicine and scientists to advances benefiting global populations.

关键词： Post-infectious irritable bowel syndrome Medical history Military medicine Gastroenteritis Travelers’diarrhea Functional gastrointestinal disorder Bacterial diarrhea

Effect of cooling rate and composition on microstructure and mechanical properties of ultrahigh-strength steels

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Journal of Iron and Steel Research International 2019年第12期26卷 1350-1365页

作者： Mohammed Ali David porter Jukka Komi Mamdouh Eissa Hoda El Faramawy Taha Mattar Materials and Mechanical Engineering Centre for Advanced Steels ResearchUniversity of OuluOulu 90014Finland Steel Technology Department Central Metallurgical Research and Development InstituteHelwanCairo 11421Egypt

The influence of cooling rate on the microstructure and mechanical properties of two new ultrahigh-strength steels(UHSSs)with different levels of C,Cr and Ni has been evaluated for the as-cooled and untempered *** UHSS had higher contents of C and Cr,while the other one had a higher Ni *** the basis of dilatation curves,microstructures,macrohardness and microhardness,continuous cooling transformation diagrams were constructed as a guide to heat treatment *** rates(CRs)of 60,1 and 0.01°C/s were selected for more detailed *** characterization was made by laser scanning confocal microscopy,field emission scanning electron microscopy combined with electron backscatter diffraction,electron probe microanalysis and X-ray *** properties were characterized using macrohardness,tensile and Charpy V-notch impact *** with the higher C and Cr contents showed lower transformation temperatures and slower bainite formation kinetics than that with the higher Ni *** cooling rates led to lower volume fractions and carbon contents of retained austenite together with finer prior austenite grain size,as well as effective final grain size and lath *** changes were accompanied by higher yield and tensile *** best combinations of strength and toughness were obtained with martensitic microstructures and by avoiding the formation of granular bainite accompanied by proeutectoid carbides at low *** the cooling rates studied,UHSS with the higher C and Cr contents showed the higher hardness and strength but at the cost of toughness.

关键词： Ultrahigh-strength steel Electroslag remelting Continuous cooling transformation diagram Microstructure feature Mechanical property

Expression of proline-rich Akt-substrate PRAS40 in cell survival pathway and carcinogenesis

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Acta Pharmacologica Sinica 2005年第10期26卷 1253-1258页

作者： Gavin porter Department of Pharmacology Emory University School of Medicine Atlanta GA 30032 USA

Aim: To study the expression of proline-rich Akt-substrate PRAS40 in the cell survival pathway and tumor progression. Methods: The effects of three key kinase inhibitors on PRAS40 activity in the cell survival pathway, serum withdrawal,U2O2and overexpression of Akt were tested. The expression of PRAS40, Akt, Raf and 14-3-3 in normal cells and cancer cell lines was determined by Western blot. Results: The PI3K inhibitors worthmannin and Ly294002, but not rapamycin, completely inhibited the phosphorylation of Akt and PRAS40. The phosphorylation level of Akt decreased after serum withdrawal and treatment with the MEK inhibi tor Uo 126, but increased after treatment with H2O2at low concentration, whereas none of these treatments changed PRAS40 activity. 14-3-3 is a PRAS40 binding protein, and the expression of 14-3-3, like that of PRAS40, was higher in HeLa cells than in HEK293 cells; PRAS40 had a stronger phosphorylation activity in A549 and HeLa cancer cells than in HEK293 normal cells. In the breast cancer model (MCF10A/MCF7) and lung cancer model (BEAS/H1198/H1170) we also found the same result: PRAS40 was constitutively active in H1198/H1170 and MCF7 premalignant and malignant cancer cells, but weakly expressed in MCF10A and BEAS normal cell. We also discussed PRAS40 activity in other NSCLC cell lines. Conclusion: The PI3K-Akt survival pathway is the main pathway that PRAS40 is involved in; PRAS40 is a substrate for Akt, but can also be activated by an Akt independent mechanisms. PRAS40 activation is an early event during breast and lung carcinogenesis.

关键词： PRAS40 PI3K-Akt pathway kinase inhibitors 14-3-3 protein

Preliminary study on the summer monsoon climate of Chinese Loess Plateau during the last interglacial period

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Chinese Science Bulletin 1996年第4期41卷 321-325页

作者：孙东怀周杰蒋复初 S.C.porter Xi'an Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi'an 710054 China Institute of Geomechanics Ministry of Geology and Mineral Resources Beijing 100086 China Quaternary Research Centre University of Washington Seattle USA

Research on long-term climatic variation on the Chinese Loess Plateau has demonstrated that loess is mainly the dust deposits transported by the northern wind of the winter monsoon, and that the paleosol accreted by r... 详细信息

关键词： last interglacial Chinese loess susceptibility.

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Prediction of Van Hove singularity systems in ternary borides

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作者： by Henry porter.

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npj Computational Materials 2023年第1期9卷 247-257页

作者： Yang Sun Zhen Zhang Andrew P.porter Kirill Kovnir Kai-Ming Ho Vladimir Antropov Department of Physics Xiamen University361005 XiamenChina Department of Physics and Astronomy Iowa State UniversityAmesIA 50011USA Department of Chemistry Iowa State UniversityAmesIA 50011USA Ames National Laboratory U.S.Department of EnergyAmesIA 50011USA

A computational search for stable structures among bothαandβphases of ternary ATB4 borides(A=Mg,Ca,Sr,Ba,Al,Ga,and Zn,T is 3d or 4d transition elements)has been *** found thatα-ATB4 compounds with A=Mg,Ca,Al,and T=V,Cr,Mn,Fe,Ni,and Co form a family of structurally stable or almost stable *** systems are metallic in non-magnetic states and characterized by the formation of the localized molecular-like state of 3d transition metal atom dimers,which leads to the appearance of numerous Van Hove singularities in the electronic *** closeness of such singularities to the Fermi level can be easily tuned by electron *** the atoms in the middle of the 3d row(Cr,Mn,and Fe),these singularities led to magnetic instabilities and magnetic ground states with a weakly metallic or semiconducting *** states appear as non-trivial coexistence of the different spin ladders formed by magnetic dimers of 3d *** magnetic states can be characterized as an analog of the spin glass *** attempts to produce MgFeB4 and associated challenges are discussed,and promising directions for further synthetic studies are formulated.

关键词： metallic ternary magnetic

A systematic review of qualitative literature on antimicrobial stewardship in Sub-Saharan Africa

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Global Health Research and Policy 2021年第1期6卷 169-179页

作者： George James porter Stephen Owens Matthew Breckons Faculty of Medical Sciences Newcastle UniversityFramlington PlaceNew-castle Upon TyneUK Department of Paediatric Immunology and Infectious Diseases Great North Children’s HospitalNewcastle Upon Tyne Hospitals NHS Foundation TrustNewcastle upon TyneUK Population Health Sciences Institute Newcastle UniversityFramlington PlaceNewcastle Upon TyneUK

Background:Antibiotic resistance is a major problem in every region of the globe and Sub-Saharan Africa(SSA)is no *** systematic reviews have addressed the prevalence of resistant organisms but few have examined the underlying causes in this *** systematic review of qualitative literature aims to highlight barriers and facilitators to antimicrobial stewardship in ***:A literature search of Embase and MEDLINE(R)was carried *** were included if they were in English,conducted in SSA,and reported qualitative data on the barriers and facilitators of antimicrobial stewardship or on attitudes towards resistance promoting *** were screened with a simple critical appraisal *** constructs were extracted and coded into concepts,which were then reviewed and grouped into themes in light of the complete ***:The literature search yielded 169 results,of which 14 studies from 11 countries were included in the final *** studies were excluded as a result of the critical *** concepts emerged from initial coding,which were consolidated into five major themes:ineffective regulation,health system factors,clinical governance,patient factors and lack of *** ineffective regulation theme highlighted the balance between tightening drugstore regulation,reducing over-the-counter sale of antibiotics,and maintaining access to medicines for rural ***,health system factors explored the tension between antimicrobial stewardship and the need of pharmacy workers to maintain profitable ***,a lack of resources,actions by patients and the day-to-day challenges of providing healthcare were shown to directly impede antimicrobial stewardship and exacerbate other factors which promote ***:Antibiotic resistance in SSA is a multi-faceted issue and while limited resources contribute to the problem they should be viewed in the context of other ***

关键词： Sub-Saharan Africa Antibiotic resistance Antibiotic stewardship Public health Global health Qualitative synthesis

Visualization of Disciplinary Profiles: Enhanced Science Overlay Maps

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Journal of Data and Information Science 2017年第3期2卷 68-111页

作者： Stephen Carley Alan L.porter Ismael Rafols Loet Leydesdorff Search Technology Inc. Program in Science Technology & Innovation Policy (STIP)School of Public PolicyGeorgia Institute of Technology Ingenio (CSIC-UPV) Universitat Politècnica de València Science Policy Research Unit (SPRU) University of Sussex Amsterdam School of Communication Research (ASCoR) University of Amsterdam

Purpose： The purpose of this study is to modernize previous work on science overlay maps by updating the underlying citation matrix, generating new clusters of scientific disciplines, enhancing visualizations, and providing more accessible means for analysts to generate their own maps Design/methodology/approach： We use the combined set of 2015 Journal Citation Reports for the Science Citation Index （n of journals = 8,778） and the Social Sciences Citation Index （n = 3,212） for a total of 11,365 journals. The set of Web of Science Categories in the Science Citation Index and the Social Sciences Citation Index increased from 224 in 2010 to 227 in 2015. Using dedicated software, a matrix of 227 × 227 cells is generated on the basis of whole-number citation counting. We normalize this matrix using the cosine function. We first develop the citing-side, cosine-normalized map using 2015 data and VOSviewer visualization with default parameter values. A routine for making overlays on the basis of the map （＂wc ***＂） is available at http：//***/wc 15/***. Findings： Findings appear in the form of visuals throughout the manuscript. In Figures 1 9 we provide basemaps of science and science overlay maps for a number of companies, universities, and technologies. Research limitations： As Web of Science Categories change and/or are updated so is the need to update the routine we provide. Also, to apply the routine we provide users need access to the Web of Science. Practical implications： Visualization of science overlay maps is now more accurate and true to the 2015 Journal Citation Reports than was the case with the previous version of the routine advanced in our ***/value： The routine we advance allows users to visualize science overlay maps in VOSviewer using data from more recent Journal Citation Reports.

关键词： Science overlay maps Science visualization Scientometrics Bibliometrics Interdisciplinary research Multidisciplinarity Research policy Research management

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Measuring and Visualizing Research Collaboration and Productivity

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Journal of Data and Information Science 2018年第1期3卷 54-74页

作者： Jon Garner Alan L.porter Andreas Leidolf Michelle Baker Search Technology Inc. School of Public Policy Georgia Institute of Technology Ecology Center Utah State University Department of Biology Utah State University

Purpose： This paper presents findings of a quasi-experimental assessment to gauge the research productivity and degree of interdisciplinarity of research center outputs. Of special interest, we share an enriched visualization of research co-authoring patterns. Design/methodology/approach： We compile publications by 45 researchers in each of 1） the iUTAH project, which we consider here to be analogous to a ＂research center,＂ 2） CG1-a comparison group of participants in two other Utah environmental research centers, and 3） CG2--a comparison group of Utah university environmental researchers not associated with a research center. We draw bibliometric data from Web of Science and from Google Scholar. We gather publications for a period before iUTAH had been established （2010-2012） and a period after （2014-2016）. We compare these research outputs in terms of publications and citations thereto. We also measure interdisciplinarity using Integration scoring and generate science overlay maps to locate the research publications across disciplines. Findings： We find that participation in the iUTAH project appears to increase research outputs （publications in the After period） and increase research citation rates relative to the comparison group researchers （although CG 1 research remains most cited, as it was in the Before period）. Most notably, participation in iUTAH markedly increases co-authoring among researchers--in general; and for junior, as well as senior, faculty; for men and women： across organizations; and across disciplines. Research limitations： The quasi-experimental design necessarily generates suggestive, not definitively causal, findings because of the imperfect controls. Practical implications： This study demonstrates a viable approach for research assessment of a center or program for which random assignment of control groups is not possible. It illustrates use of bibliometric indicators to inform R＆D program management. Originality/value： New visualizations

关键词： Bibliometrics Interdisciplinarity Multidisciplinarity Research evaluation Research collaboration mapping Science visualization Scientometrics Social networkanalysis

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