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Forced Vibration of the Non-Homogeneously Pre-Stressed System Consisting of the Hollow Cylinder and Surrounding Medium

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Computer Modeling in Engineering & Sciences 2019年第10期121卷 315-348页

作者： Surkay D.Akbarov emin t.Bagirov Department of Mechanical Engineering Yildiz Technical UniversityYildiz Campus34349BesiktasIstanbulTurkey Institute of Mathematics and Mechanics of the National Academy of Sciences of Azerbaijan 37041BakuAzerbaijan.

the paper deals with the study of the influence of the non-homogeneous prestresses in the system consisting of the hollow cylinder and surrounding elastic medium on the frequency response of this system caused by the time-harmonic ring load acting in the interior of the *** axisymmetric problem is considered and it is assumed that in the initial state,the system is compressed in the radial direction with homogeneously distributed static forces as a result of which,non-homogeneous pre-stresses(or initial stresses)appear in *** is also assumed that after these pre-stresses appear in the interior of the cylinder,the point-located(with respect to the axial coordinate directed along the cylinder’s central axis)additional time-harmonic ring load ***,it is required to determine how the pre-stresses influence the frequency response of the system to the noted additional time-harmonic *** influence,which is the non-linear effect,is studied within the scope of the so-called three-dimensional linearized equations and relations of the theory of elastic waves in pre-stressed *** solution to the corresponding boundary value problems is found by employing the discrete analytical solution method and numerical results on the influence of the pre-stresses on the frequency response of the interface stresses which appear as a result of the action of the additional time-harmonic forces,are presented and *** particular,it is established that the pre-stresses mentioned above cause to decrease the magnitude of the interface dynamic stresses appearing as a result of the additional time-harmonic loading.

关键词： Non-linear effect inhomogeneous initial stresses frequency response timeharmonic ring load hollow cylinder surrounding medium

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Red cell distribution width-to-albumin ratio is a simple promising prognostic marker in acute cholangitis requiring biliary drainage

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 487-494页

作者： Fatih Acehan Hüseyin Camli Cagdas Kalkan Mesut tez Burak Furkan Demir emin Altiparmak Ihsan Ates Department of Internal Medicine Ankara City HospitalAnkara 06800Türkiye Department of Gastroenterology Ankara City HospitalAnkara 06800Türkiye Department of General Surgery Ankara City HospitalAnkara 06800Türkiye

Background: It is crucial to assess the severity of acute cholangitis(AC). there are currently several prognostic markers. However, the accuracies of these markers are not satisfied. the present study aimed to investigate the predictive value of the red cell distribution width(RDW)-to-albumin ratio(RAR) for the prognosis of AC. Methods: We retrospectively evaluated consecutive patients diagnosed with AC between May 2019 and March 2022. RAR was calculated, and its predictive ability for in-hospital mortality, intensive care unit(ICU) admission, bacteremia, and the length of hospitalization were analyzed. Results: Out of 438 patients, 34(7.8%) died. Multivariate analysis showed that malignant etiology [odds ratio(OR) = 4.816, 95% confidence interval(CI): 1.936-11.980], creatinine(OR = 1.649, 95% CI: 1.095-2.484), and RAR(OR = 2.064, 95% CI: 1.494-2.851) were independent risk factors for mortality. When adjusted for relevant covariates, including age, sex, malignant etiology, tokyo severity grading(tSG), Charlson comorbidity index, and creatinine, RAR significantly predicted mortality(adjusted OR = 1.833, 95% CI: 1.280-2.624). When the cut-off of RAR was set to 3.8, its sensitivity and specificity for mortality were 94.1% and 56.7%, respectively. Patients with an RAR of > 3.8 had a 20.9-fold(OR = 20.9, 95% CI: 4.9-88.6) greater risk of mortality than the remaining patients. the area under the curve value of RAR for mortality was 0.835(95% CI: 0.770-0.901), which was significantly higher than that of tSG and the other prognostic markers, such as C-reactive protein-to-albumin ratio, and procalcitonin-to-albumin ratio. Lastly, RAR was not inferior to tSG in predicting ICU admission, bacteremia, and the length of hospitalization. Conclusions: RAR successfully predicted the in-hospital mortality, ICU admission, bacteremia, and the length of hospitalization of patients with AC, especially in-hospital mortality. RAR is a promising marker that is more convenient than tSG and o

关键词： Acute cholangitis Albumin Biliary drainage Mortality Red blood cell distribution width-to-albumin ratio

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浅谈VC和创业者的关系

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杭州科技 2015年第5期36卷 61-62页

作者： t.emin

风投很“疯”风投的意义可以这样概括：用资金支持一个创业者实现梦想，并且成为这个梦想的一部分，有时候甚至是全面渗透到这个梦想之中。风投的工作过程其实也是枯燥的，从业者每天都要面对很多项目，

关键词：创业者 VC 资金支持

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Facile synthesis of NiMn2S4 nanoflakes on nickel foam for high-performance aqueous asymmetric supercapacitors

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Science China(technological Sciences) 2024年第2期67卷 499-508页

作者： ADIL emin LI YaLi GAO Zhe DONG YunXia LI DongHao CHEN YongChao FU YuJun HE DeYan LI JunShuai LONGi Institute of Future technology and School of Materials&EnergyLanzhou UniversityLanzhou 730000China

Supercapacitors display promising electrochemical performance with high power density and excellent cycle ***,their low energy density limits their advancement in a broader range of *** enhance their energy density,we proposed self-assembled spinel NiMn2S4nanoflakes grown on nickel foam which we successfully prepared by a facile hydrothermal *** NiMn2S4electrode delivers a high capacitance of 2096.7 F g^(-1)at 1.0 A g^(-1),with an exceptional rate capability(~720.6 F g^(-1)at a very high current density of 100 A g^(-1))and good cycle stability(~85.1%retention of the initial capacitance after 7000 cycles with the Coulombic efficiency around 100%).the as-fabricated asymmetric supercapacitors based on NiMn2S4nanoflakes//active carbon demonstrate an energy density of 73.6 W h kg^(-1)at 800.5 W kg^(-1)and adequate cycling performance of~84.6%capacitance retention at 15 A g^(-1)after 10000 *** results reveal that the nanostructured NiMn2S4is an excellent electrode material for high-performance energy storage applications.

关键词： NiMn2S4 nanostructure high capacitance aqueous supercapacitors long cycle stability high energy density

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Condition indices for rigid pavements: A comparative analysis of state DOts using Michigan PMS data

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Journal of Road Engineering 2024年第3期4卷 348-360页

作者： Rahul Raj Singh Mumtahin Hasnat Muhammed emin Kutay Syed Waqar Haider James Bryce Bora Cetin Department of Civil and Environmental Engineering Michigan State UniversityEast LansingMI 48824USA Wadsworth Department of Civil and Environmental Engineering West Virginia UniversityMorgantownWV 26506USA

Pavement infrastructure is vital in providing services and links between various sectors of society. therefore, thepreservation and maintenance of these roads are critical to attaining a pavement network in good conditionthroughout its service life. Various performance indicators like the international roughness index (IRI), pavementcondition index (PCI), and present serviceability rating (PSR) have been used by the state department of transportation (DOt) and highway agencies for evaluating pavement surface conditions and planning future maintenance strategies. Limited data availability, multiple distresses depending on region, lack of correlation of thesecondition indices to maintenance strategies, and data collection limitations pose a challenge for applying theseindices to local conditions. this paper compares condition indices of different states for rigid pavements. Further,using a specific condition index for local conditions is also highlighted. For this purpose, five states and theircorresponding condition indices were evaluated and compared to the Michigan DOt distress index (DI). thesestates include Virginia, Minnesota, North Dakota, Louisiana, and Oregon. the corresponding distresses of eachcondition index were converted to make them compatible with the MDOt DI. this study used the MDOt'spavement management system (PMS) database to evaluate each condition index for 433 rigid pavement *** distress index was plotted against MDOt DI and compared using a paired t-test. Results show that thecondition indices of Virginia and Minnesota are comparable to DI in terms of the Spearman correlation value. thet-test results show that except for Virgina, condition indices from other states statistically differ from ***, one can't use those directly for local conditions in Michigan. this paper presents the evaluation anddata requirements for each condition index and its impact on selecting a maintenance treatment.

关键词： Rigid pavement Pavement management Condition index Distress index

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钢熔炼和精炼系统理论与实践的进展：炼钢的现状和展望

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钢铁译文集 1995年第2期 71-77页

作者： emin,t 朱Hong溢

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Preparation of microparticles and nanoparticles using membrane-assisted dispersion,micromixing,and evaporation processes

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Particuology 2024年第1期84卷 30-44页

作者： Goran t.Vladisavljevic Chemical Engineering Department Loughborough UniversityLoughboroughLeicestershire LE113TUUnited Kingdom

Synthetic microporous membranes are increasingly used for energy-efficient and controlled production of micro-and nanoparticles and micro-and nanoemulsions with tuneable morphology and physico-chemical properties through various micromixing,emulsification,and evaporation *** emul-sification processes,the membrane pores are used for dispersed phase injection and size-controlled generation of droplets and droplet-templated *** micromixing processes,membrane is utilised as a micromixer for mixing two miscible liquids,usually solvent and antisolvent-rich solutions,which leads to the creation of supersaturation and subsequent nanoprecipitation or *** mem-brane evaporation processes,membrane is used to prevent phase dispersion while allowing efficient molecular diffusion of solvent and/or antisolvent vapour through gas-filled *** dispersion processes can be operated continuously by decoupling shear stress on the membrane surface from cross flow using tube insets,flow pulsations,swirling flow,membrane oscillations or membrane *** generation and solidification can be performed continuously in a single pass by connecting membrane module with a downstream *** dispersion processes can be used for pro-duction of nanoparticles such as nanovesicles(liposomes,micelles,ethosomes,and niosomes),nanogels,polymeric,lipid and metallic nanoparticles,and *** main advantages of membrane-assisted particle generation are in low energy consumption,controlled geometry and hydrodynamic conditions at the microscale level,flexible throughput due to modular and scalable design of membrane devices,and a wide choice of available microporous membranes with various wall porosities,wetta-bilities,pore sizes,and pore morphologies to suit different applications.

关键词： Nanoparticles Microparticles Nanoemulsions Microemulsions Microporous membrane Crystallisation Flash nanoprecipitation Emulsification Zero liquid discharge

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Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

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Condition indices for rigid pavements: A comparative analysis of state DOts using Michigan PMS data

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Journal of Road Engineering 2024年第03期 348-360页

作者： Rahul Raj Singh Mumtahin Hasnat Muhammed emin Kutay Syed Waqar Haider James Bryce Bora Cetin Department of Civil and Environmental Engineering Michigan State University Wadsworth Department of Civil and Environmental Engineering West Virginia University

Pavement infrastructure is vital in providing services and links between various sectors of society. therefore, the preservation and maintenance of these roads are critical to attaining a pavement network in good condition throughout its service life. Various performance indicators like the international roughness index(IRI), pavement condition index(PCI), and present serviceability rating(PSR) have been used by the state department of transportation(DOt) and highway agencies for evaluating pavement surface conditions and planning future maintenance strategies. Limited data availability, multiple distresses depending on region, lack of correlation of these condition indices to maintenance strategies, and data collection limitations pose a challenge for applying these indices to local conditions. this paper compares condition indices of different states for rigid pavements. Further,using a specific condition index for local conditions is also highlighted. For this purpose, five states and their corresponding condition indices were evaluated and compared to the Michigan DOt distress index(DI). these states include Virginia, Minnesota, North Dakota, Louisiana, and Oregon. the corresponding distresses of each condition index were converted to make them compatible with the MDOt DI. this study used the MDOt's pavement management system(PMS) database to evaluate each condition index for 433 rigid pavement *** distress index was plotted against MDOt DI and compared using a paired t-test. Results show that the condition indices of Virginia and Minnesota are comparable to DI in terms of the Spearman correlation value. the t-test results show that except for Virgina, condition indices from other states statistically differ from ***, one can't use those directly for local conditions in Michigan. this paper presents the evaluation and data requirements for each condition index and its impact on selecting a maintenance treatment.

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Beta-lactam antibiotic resistance among Escherichia coli isolates from patients with urinary tract infections in Vietnam:A systematic review and meta-analysis

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Asian Pacific Journal of tropical Medicine 2024年第6期17卷 243-255,I0001-I0003页

作者： Dat t Nguyen Princess Margaret Cancer Centre University Health NetworkTorontoOntarioCanada

Objective:to investigate the evolving patterns of antimicrobial resistance against beta-lactam antibiotics in Escherichia coli isolates from urinary tract infection patients in Vietnam,covering the period from 2005 to ***:29 Descriptive studies published between 2010 and 2022 in English and Vietnamese were included in the *** on resistance rates to beta-lactam antibiotics,including cephalosporins and carbapenems,were extracted and *** pooled resistance rates were calculated using random-effects *** trends in resistance were assessed using linear regression ***:Among the beta-lactam antibiotics studied,Escherichia coli exhibited varying levels of resistance,with cephalosporins showing higher resistance rates compared to *** pooled resistance rates were 66%for cefotaxime,65%for ceftriaxone,54%for ceftazidime,and 56%for *** contrast,carbapenems demonstrated lower resistance rates,with weighted pooled resistance rates ranging from 3%to 4%for meropenem,ertapenem,and *** rates were also observed for amoxicillin/clavulanate(35%),ticarcillin/clavulanate(26%),and piperacillin/tazobactam(12%).Significant annual increases in resistance were noted for imipenem(0.56%,Pthis study highlights the critical issue of antimicrobial resistance in urinary tract infections in Vietnam and emphasizes the importance of prudent antibiotic use and the regular monitoring of resistance *** insights are useful for guiding healthcare professionals in optimizing treatment strategies and for policymakers in formulating evidence-based clinical guidelines to combat antibiotic resistance effectively.

关键词： Antimicrobial resistance Urinary tract infection Vietnam

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