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Fracture strength evaluation of titanium alloys using modified average stress criterion

Transactions of Nonferrous Metals Society of China 2013年第4期23卷 1072-1079页

作者： h.brighton isaac john T.ChRISTOPhER Sardar Raja College of Engineering AlangulamTirunelveli-627808India Government College of Engineering PerumalpuramTirunelveli-627007India

Structural integrity procedures were used to demonstrate the fitness for the purpose of engineering components transmitting loads. The prediction of the fracture strength of titanium alloys containing sharp notches through the damage model depends on the un-notched strength and the critical length of the damage zone ahead of the notch. In general, the critical length of the damage zone depends on the material, specimen, and size of the sharp notch. Modifications were made in one of the stress fracture criteria known as the average stress criterion for accurate prediction of notched tensile strength of titanium alloy specimen containing sharp notches. To examine the adequacy of these modifications, fracture data of center-cracked titanium alloys with various thicknesses are considered. The notched （fracture） strength estimates are found to be close to the test results. The modified average stress criterion is very simple to predict the notched tensile strength.

关键词： titanium alloys center crack tensile specimen stress criterion failure assessment diagram fracture strength

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Distinct risk factors for early and late blood transfusion following pancreaticoduodenectomy

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hepatobiliary & Pancreatic Diseases International 2018年第4期17卷 349-357页

作者： Sukhchain S.Bansal James hodson Khalid Khalil Bobby Dasari Ravi Marudanayagam Robert P.Sutcliffe john isaac Keith J.Roberts Department of hepatobiliary Pancreatic Surgery Queen Elizabeth Hospital BirminghamUniversity Hospitals Birmingham Institute of Translational Medicine Queen Elizabeth Hospital BirminghamUniversity Hospitals Birmingham

Background: The International Study Group of Pancreatic Surgery(ISGPS) has defined two periods of postpancreatectomy hemorrhage, early(24 h). A previously published Blood Usage Risk Score(BURS) aimed to predict early ... 详细信息

Background: The International Study Group of Pancreatic Surgery(ISGPS) has defined two periods of postpancreatectomy hemorrhage, early(h) and late(>24 h). A previously published Blood Usage Risk Score(BURS) aimed to predict early and late blood transfusion. The primary aim of this study was to define risk factors for early and late blood transfusion after pancreaticoduodenectomy. Secondary aims were to assess the predictive accuracy of the ***: In this retrospective observational study, multivariable analyses were used to identify independent risk factors for both early and late blood transfusion. The predictive ability of the BURS was then assessed using a receiver operating characteristic(ROC) curve ***: Among 628 patients, 99(15.8%) and 144(22.9%) received early and late blood transfusion, respectively. Risk factors for blood transfusion differed between early and late periods. Preoperative anemia and venous resection were associated with early blood transfusion whilst Whipple’s resection(as opposed to pylorus preserving pancreaticoduodenectomy), lack of biliary stent and a narrow pancreatic duct were predictors of late blood transfusion. The BURS was significantly predictive of early blood transfusion,albeit with a modest degree of accuracy(AUROC: 0.700, P h increasing severity of postoperative pancreatic fistula(POPF)(OR: 1.85, 3.18 and 9.97 for biochemical, types B and C POPF,respectively, relative to no POPF).Conclusions: Two largely different sets of variables are related to early and late blood transfusion following pancreaticoduodenectomy. The BURS was significantly associated with early, albeit with modest predictive accuracy, but not late blood transfusion. An understanding of POPF risk allows assessment of the need for late blood transfusion.

关键词： Pancreatic cancer Blood transfusion Pancreaticoduodenectomy

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The organization of societal conflicts by pavement ants Tetramorium caespitum： an agent-based model of amine-mediated decision making

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Current Zoology 2016年第3期62卷 277-284页

作者： Kevin M. hOOVER Andrew N. BUBAK isaac J. LAW Jazmine D. W. YAEGER Kenneth J. RENNER john G. SWALLOW Michael J. GREENE Department of Integrative Biology University of Colorado Denver Denver CO 80217-3364 USA Neuroscience Program University of Colorado Anschutz Medical Campus Aurora CO 80045 USA Department of Biology University of South Dakota Vermillion South Dakota 57069 USA

Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant＇s brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the ter- ritory that they patrol in search of energetically rich forage. When members of 2 colonies randomly interact at the territory boundary a decision to fight occurs when： 1） there is a mismatch in nest- mate recognition cues and 2） each ant has a recent history of high interaction rates with nestmate ants. Instead of fighting, some ants will decide to recruit more workers from the nest to the fighting location, and in this way a positive feedback mediates the development of colony wide wars. In ants, the monoamines serotonin （5-hT） and octopamine （OA） modulate many behaviors associated with colony organization and in particular behaviors associated with nestmate recognition and ag- gression. In this article, we develop and explore an agent-based model that conceptualizes how in- dividual changes in brain concentrations of 5-hT and OA, paired with a simple threshold-based de- cision rule, can lead to the development of colony wide warfare. Model simulations do lead to the development of warfare with 91% of ants fighting at the end of 1 h. When conducting a sensitivity analysis, we determined that uncertainty in monoamine concentration signal decay influences the behavior of the model more than uncertainty in the decision-making rule or density. We conclude that pavement ant behavior is consistent with the detection of interaction rate through a single timed interval rather than integration of multiple interactions.

关键词： agent-based model aggressive behavior ants decision making monoamines octopamine serotonin.

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Efficacy of Tocilizumab in Patients hospitalized with Covid-19

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四川生理科学杂志 2021年第1期43卷 98-98页

作者： john h Stone From Massachusetts General hospital (J.h.S. M.J.F. N.J.S.-B. A.D.F. L.H. A.S.F. N.K.H. B.C.H. C.A.S. M.D. C.M.N. Y.-D.H. T.K.T. Z.D. A.S. R.S.W. A.Y.K. S.S. P.S. T.G.N. C.A.P. S.H.U. D.S.C. M.A.M. J.M.Y. K.A.B. E.M. A.Z. Z.D.D. M.B.B. M.K. K.M.D. J.D. M.M.L. M.K.M.) Brigham and Women’s Hospital (A.E.W. S.N. B.N.W.) and Boston Medical Center (N.L. M.S.) Boston North Shore Medical Center Salem (R.S. A.M.B. C.C.) Newton–Wellesley Hospital Newton (H.S. D.S.H.) Beth Israel Lahey Health Burlington (M.A. M.D.P.) and St. Elizabeth’s Medical Center Brighton (J.F.) — all in Massachusetts.

Background:The efficacy of interleukin-6 receptor blockade in hospitalized patients with coronavirus disease 2019(Covid-19)who are not receiving mechanical ventilation is ***:We performed a randomized,double-blind,placebo-controlled trial involving patients with confirmed severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection,hyperinflammatory states,and at least two of the following signs:fever(body temperature>38℃),pulmonary infiltrates,or the need for supplemental oxygen in order to maintain an oxygen saturation greater than 92%.

关键词： acute respiratory Patients

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GUIDEA—Guidance for Dietary Intake and Exposure Assessment—A New Resource for Exposure Assessment Professionals

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Food and Nutrition Sciences 2013年第3期4卷 315-320页

作者： john howlett Neil Buck Matthew Buck Jeanne h. M. de Vries Veronika Ehrlich Melody hove Astrid G. Kruizinga Pratima R. Jasti Benjamin Smith David Tennant DSM Basel Switzerland Firmenich S.A. Geneva Switzerland Food Chemical Risk Analysis Brighton UK ILSI Europe A.I.S.B.L. Brussels Belgium Nestec LTD. Lausanne Switzerland RatwareUK Skelmersdale UK TNO Triskelion Zeist The Netherlands Wageningen University Wageningen Wageningen University Wageningen The Netherlands West hill Wembley Park UK

Exposure assessment is a key component of any risk-benefit assessment, yet it is clear that there is a lack of reliable methodology in this area for assessing consumer exposures to both food constituents and nonfood products. The International Life Sciences Institute (ILSI) Europe Food Intake Methodology Task Force has in the past explored methods to assess the intake of nutrients/additives and exposure to contaminants/residues from food. In December 2008, a workshop was held to discuss the differences between different types of exposure assessments as well as the difficulties involved in the practical application of the methods available. It was noted that although no two assessments are the same in terms of data required and its availability, or the assumptions made, there is also wide and perhaps unnecessary variation between the approaches taken by different assessors. As a result, the ILSI Europe Food Intake Methodology Task Force initiated an activity aimed at producing a practical guide for conducting intake/exposure assessments in the form of an interactive web-based application. During the course of this work it became clear that the best form in which to present the guide would be a web-based MediaWiki-type system. A website was developed and launched in October 2012, at which time global experts and practitioners in dietary exposure assessment were invited to register to use the site and help keep the knowledge contained within it, relevant and up-to-date. It is hoped that the guide will be an important reference source for a wide group of stakeholders, providing concise guidance on the planning, conduct, reporting and interpretation of exposure assessments and contributing to greater harmonisation of the dietary intake/exposure methodologies used.

关键词： Exposure Assessment Intake Assessment Risk Assessment Online Resource

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