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Acta Mechanica Sinica 2016年第3期32卷 397-405页

作者： sahra azma Ghader Rezazadeh Rasoul Shabani Elnaz Alizadeh-Haghighi Department of Mechanical Engineering Faculty of Engineering Urmia University

Viscous damping is a dominant source of energy dissipation in laterally oscillating micro-structures. In microresonators in which the characteristic dimensions are comparable to the dimensions of the fluid molecules, the assumption of the continuum fluid theory is no longer justified and the use of micro-polar fluid theory is indispensable. In this paper a mathematical model was presented in order to predict the viscous fluid damping in a laterally oscillating finger of a micro-resonator considering micro-polar fluid theory. The coupled governing partial differential equations of motion for the vibration of the finger and the micro-polar fluid field have been derived. Considering spin and no-spin boundary conditions, the related shape functions for the fluid field were presented. The obtained governing differential equations with time varying boundary conditions have been transformed to an enhanced form with homogenous boundary conditions and have been discretized using a Galerkin-based reduced order model. The effects of physical properties of the micro-polar fluid and geometrical parameters of the oscillating structure on the damping ratio of the system have been investigated.

关键词： Micro-electro-mechanical systems(MEMS) Micro-resonator Micro-polar theory Viscous fluid damping Galerkin method

The emergence of drug resistant HIV variants and novel anti-retroviral therapy

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Asian Pacific Journal of Tropical Biomedicine 2013年第7期3卷 515-522页

作者： Koosha Paydary Parisa Khaghani sahra Emamzadeh-Fard Seyed Ahmad Seyed Alinaghi Kazem Baesi Iranian Research Center for HIV/AIDS (IRCHA) Iranian Institute for Reduction of High-Risk Behaviors Tehran University of Medical SciencesTehran Iran Students'Scientific Research Center Tehran University of Medical SciencesTehran Iran

After its identification in 1980s,HIV has infected more than 30 million people *** era of highly active anti-retroviral therapy,anti-retroviral drug resistance results frominsufficient anti-retroviral pressure,which may lead to treatment *** studiessupport the idea that anti-retroviral drug resistance has evolved largely as a result of low-adherence of patients to therapy and extensive use of anti-retroviral drugs in the developedworld;however,a highly heterogeneous horde of viral quasi-species are currently circulating indeveloping ***,the prioritizing of strategies adopted in such two worlds should be quitedifferent considering the varying anti-retroviral drug resistance *** this article,weexplore differences in anti-retroviral drug resistance patterns between developed and developingcountries,as they represent two distinct ecological niches of HIV from an evolutionary standpoint.

关键词： HIV infection Evolution,Drug resistance Developed world Developing world

Clostridioides difficile infection in liver cirrhosis patients: A population-based study in United States

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World Journal of Hepatology 2021年第8期13卷 926-938页

作者： Syeda sahra Mohammad Abureesh Shivantha Amamath Motasem Alkhayyat Rawan Badran Abdullah Jahangir Vivek Gumaste Department of Internal Medicine Staten Island University HospitalStaten IslandNY 10305United States Department of Internal Medicine Cleveland Clinic FoundationClevelandOH 44195United States Department of Gastroenterology Staten Island University HospitalStaten IslandNY 10305United States

BACKGROUND Clostridioides(formerly Clostridium)difficile infection(CDI)is an increasingly frequent cause of morbidity and mortality in hospitalized *** risk factors are documented in the literature that includes,but are not limited to,antibiotics use,advanced age,and gastric acid *** epidemiological studies have reported an increased incidence of CDI in advanced liver disease *** have also demonstrated a higher prevalence of nosocomial infections in cirrhotic *** To use a large nationwide database,we sought to determine CDI’s risk among liver cirrhosis patients in the United *** We queried a commercial database(Explorys Inc^(TM),Cleveland,OH,United States),and obtained an aggregate of electronic health record data from 26 major integrated United States healthcare systems comprising 360 hospitals in the United States from 2018 to *** were organized into the Systematized Nomenclature of Medicine Clinical Terms(SNOMED–CT)*** analysis for the multivariable model was performed using Statistical Package for Social Sciences(SPSS version 25,IBM CorpTM).For all analyses,a two-sided P value of<0.05 was considered statistically *** There were a total of 19387760 patients in the database who were above 20 years of age between the years *** those,133400 were diagnosed with liver *** prevalence of CDI amongst the liver cirrhosis population was 134.93 per 100.000 vs 19.06 per 100.000 in non-cirrhotic patients(P<0.0001).The multivariate analysis model uncovered that cirrhotic patients were more likely to develop CDI(OR:1.857;95%CI:1.665-2.113,P<0.0001)compared to those without any prior history of liver *** In this large database study,we uncovered that cirrhotic patients have a significantly higher CDI prevalence than those without *** cirrhosis may be an independent risk factor for *** prospective studies are needed to cl

关键词： patients cirrhosis infection

PERCEPOLIS: Pervasive Cyberinfrastructure for Personalized Learning and Instructional Support

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Intelligent Information Management 2010年第10期2卷 586-596页

作者： Ali R. Hurson sahra Sedigh 不详

This paper describes PERCEPOLIS, an educational platform that leverages technological advances, in particular in pervasive computing, to facilitate personalized learning in higher education, while supporting a networked curricular model. Fundamental to PERCEPOLIS is the modular approach to course development. Blended instruction, where students are responsible for perusing certain learning objects outside of class, used in conjunction with the cyberinfrastructure will allow the focus of face-to-face meetings to shift from lecture to active learning, interactive problem-solving, and reflective instructional tasks. The novelty of PERCEPOLIS lies in its ability to leverage pervasive and ubiquitous computing and communication through the use of intelligent software agents that use a student’s academic profile and interests, as well as supplemental information such as his or her learning style, to customize course content. Assessments that gauge the student’s mastery of concepts are used to allow self-paced progression through the course. Furthermore, the cyberinfrastructure facilitates the collection of data on student performance and learning at a resolution that far exceeds what is currently available. We believe that such an infrastructure will accelerate the acquisition of knowledge and skills critical to professional engineering practice, while facilitating the study of how this acquisition comes about, yielding insights that may lead to significant changes in pedagogy.

关键词： Learning Technology Personalized Learning Cyberinfrastructure Pervasive Computing.

Equilibrium and Kinetic Studies of Reactive Black 8 Adsorption onto Crosslinked Chitosan Beads

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Journal of Chemistry and Chemical Engineering 2019年第1期13卷 1-7页

作者： sahra Dandil Deniz Akin Sahbaz Caglayan Acikgoz Department of Chemical Engineering Faculty of Engineering Bilecik Seyh Edebali University Bilecik 11230 Turkey Department of Chemical Engineering Faculty of Engineering Afyon Kocatepe University Afyonkarahisar 03200 Turkey

Environmental pollution problems by the discharge of effluent containing various contaminations from textile, paper and paint industries have become a serious issue in recent years. Dye removal from wastewater has received considerable attention for several adsorbents and several classes of dye. Reactive black 8 is an environmentally hazardous dye and most applicable in textile industries. Chitosan is a non-toxic, biodegradable and biocompatible and acts as an efficient adsorbent because of the amino functional groups. In the present work, the crosslinked chitosan beads were synthesized by using glutaraldehyde as a crosslinker and the adsorptive removal of reactive black 8 by the beads from an aqueous solution was investigated. The effect of contact time and initial dye concentration was evaluated. The adsorbent dosage was retained as 1 g/L and initial dye concentration values were varied from 30 to 150 mg/L. Equilibrium isotherms were analysed by Langmuir, Freundlich, Dubnin–Radushkevich, and Temkin isotherm. Freundlich isotherm model was found fit effectively for the reactive black 8 adsorptions. Kinetic adsorption data were evaluated using the pseudo-first-order kinetic model, the pseudo-second-order kinetic model and the intraparticle diffusion model. The adsorption followed pseudo second order kinetics. Overall, this study indicates chitosan beads as an efficient, eco-friendly and low-cost adsorbent for the removal of reactive black 8 dye from aqueous solutions.

关键词： Adsorption chitosan kinetics reactive black 8

Prevalence survey of infection with Treponema pallidum among HIV-positive patients in Tehran

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Asian Pacific Journal of Tropical Biomedicine 2013年第4期3卷 334-336页

作者： Banafsheh Moradmand Badie Zeinab Yavari Shooka Esmaeeli Koosha Paydary sahra Emamzadeh-Fard SeyedAhmad SeyedAlinaghi Mehrnaz Rasoulinejad Iranian Research Center for HIV/AIDS Tehran University of Medical SciencesTehranIran Students' Scientific Research Center(SSRC) Tehran University of Medical SciencesTehranIran

Objective:To identify the frequency of syphilis among Iranian HIV-positive ***:A cross-sectional study on the prevalence of syphilis and HIV co-infection among 450 patients diagnosed with HIV infection was conducted between 2004 and 2008 at Imam Khomeini hospital,Tehran,*** lab tests including CD4 cell count,cerebrospinal fluid,veneral disease research laboratory(VDRL),fluorescent treponema antibody-absorption(FTA-Abs)and viral load were performed for all the *** regarding medical history and their demographics were also ***:Of all 450 HIV-positive patients,24(5.3%)had a positive VDRL test and only two men had a FTA-Abs positive test which means 0.45%of them had a definite co-infection of syphilis.65.3%of the HIV-positive patients were injection drug users that the co-infection prevalence of them was 0.7%.We did not find any patient with ***:Considering the increasing prevalence of HIV and also extensive use of highly active antiretroviral therapy in developing nations,the diagnosis of syphilis should be timely established using screening tests among such patients.

关键词： Syphilis HIV/AIDS Co-infection

年终犒赏肌肤的修复大计——10款密集修护产品推荐

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中国化妆品 2009年第23期 62-63页

作者： sahra

年底是人们犒赏自己的最佳时刻，肌肤也一样需要最好的呵护，将一年的疲劳消除，以崭新的姿态迎接新年，10款密集修护产品，让你的肌肤享尽万千宠爱，在最短的时间以新面貌示人。

关键词：产品推荐肌肤修护密集修复最佳时刻

Prevalence of HIV infection and the correlates among homeless in Tehran,Iran

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Asian Pacific Journal of Tropical Biomedicine 2014年第1期4卷 65-68页

作者： Abbas Ostad Taghi zadeh SeyedAhmad SeyedAlinaghi Farshad Fakhimi Hassanzad Mehdi Hajizadeh SeyedNajmeddin Mohamadi sahra Emamzadeh-Fard Koosha Paydary Mostafa Hosseini Department of Disaster Public Health School of Public HealthTehran University of Medical Sciences(TUMS) Iranian Research Center for HIV/AIDS(IRCHA) Iranian Institute for Reduction of High-Risk BehaviorsTehran University of Medical Sciences(TUMS) Welfare Services and Social Participations Organization Students' Scientific Research Center(SSRC) Tehran University of Medical Sciences(TUMS) Department of Epidemiology and Biostatistics School of Public HealthTehran University of Medical Sciences(TUMS)

Objective:To determine the prevalence of HIV infection among homeless men and women and the related risk behaviors in Tehran,***:In 2007-2008,Tehran municipality stacked up 10657 homeless men and women for assessment of HIV and began collaboration with Iranian Research Center for HIV/AIDS(IRCHA)departments to conduct HIV infection prevalence surveys in homeless *** results were analyzed for associations with demographic information,family support,status of drug abuse and relation with family and ***:Overall HIV prevalence was 1.7%(95%confidence interval 1.4-1.9).Factors independently associated with HIV infection included history of using drugs[AOR 8.15(4.86-13.67)].older age[AOR1.80(1.08-2.99)for 40-55 yr],occupation[AOR 1.64(1.19-2.24)for unemployed],and no relation with family[AOR 1.82(l.30-2.54)|.Conclusions:This study supports the idea that injection drug use is contributing to the increased spread of HIV among Iranian *** reduction programs should be expanded,particularly among homeless injection drug users.

关键词： Homeless HIV infection Prevalence

Association between human leukocyte antigen gene polymorphisms and multiple EPIYA-C repeats in gastrointestinal disorders

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World Journal of Gastroenterology 2020年第32期26卷 4817-4832页

作者： Suat Saribas Suleyman Demiryas Erkan Yilmaz Omer Uysal Nuray Kepil Mehmet Demirci Reyhan Caliskan Harika Oyku Dinc Seher Akkus Nesrin Gareayaghi sahra Kirmusaoglu Dogukan Ozbey Hrisi B Tokman Serdar S Koksal Ihsan Tasci Bekir Kocazeybek Department of Medical Microbiology Istanbul University-CerrahpasaCerrahpasa Medical FacultyIstanbul 34098Turkey Department of General Surgery Istanbul University-CerrahpasaCerrahpasa Medical FacultyIstanbul 34098Turkey Department of Organ Transplantation HLA LaboratoryIstanbul University-CerrahpasaCerrahpasa Medical FacultyIstanbul 34098Turkey Deparment of Biostatistics Medical School of Bezmialem Vakif UniversityIstanbul 34093Turkey Department of Pathology Istanbul University-CerrahpasaCerrahpasa Medical FacultyIstanbul 34098Turkey Department of Medical Microbiology Beykent University Medical FacultyIstanbul 34520Turkey Center for Blood Istanbul Sisli Hamidiye Etfal Training and Research HospitalUniversity of Health SciencesIstanbul 34360TurkeyDepartment of Molecular Biology and GeneticsT.C.Halic UniversityFaculty of Arts&SciencesIstanbul 34381Turkey Department of Public Health Istanbul University-CerrahpasaCerrahpasa Medical FacultyIstanbul 34098Turkey

BACKGROUND Polymorphisms of human leukocyte antigen(HLA)genes are suggested to increase the risk of gastric cancer(GC).AIM To investigate the HLA allele frequencies of patients with GC relative to a control group in terms of CagA+multiple(≥2)EPIYA-C *** The patient group comprised 94 patients[44 GC and 50 duodenal ulcer(DU)patients],and the control group comprised 86 individuals[(50 non-ulcer dyspepsia patients and 36 people with asymptomatic Helicobacter pylori(***)].Polymerase chain reaction was performed for the amplification of the *** cagA gene and typing of EPIYA *** sequence-specific oligonucleotide(SSO)typing was performed using Lifecodes SSO typing kits(HLA-A,HLA-B HLA-C,HLA-DRB1,and HLA-DQA1-B1 kits).RESULTS The comparison of GC cases in terms of CagA+multiple(≥2)EPIYA-C repeats showed that only the HLA-DQB1*06 allele[odds ratio(OR):0.37,P=0.036]was significantly lower,but significance was lost after correction(Pc=0.1845).The HLA-DQA1*01 allele had a high ratio in GC cases with multiple EPIYA-C repeats,but this was not significant in the univariate *** compared allele frequencies in the DU cases alone and in GC and DU cases together using the same criterion,and none of the HLA alleles were significantly associated with GC or ***,none of the alleles were detected as independent risk factors after the multivariate *** the other hand,in a multivariate logistic regression with no discriminative criterion,HLA-DQA1*01(OR=1.848),HLA-DQB1*06(OR=1.821)and HLA-A*02(OR=1.579)alleles were detected as independent risk factors for GC and *** None of the HLA alleles were detected as independent risk factors in terms of CagA+multiple EPIYA-C ***,HLA-DQA1*01,HLA-DQB1*0601,and HLA-A*2 were independent risk factors with no criterion in the multivariate *** suggest that the association of these alleles with gastric malignancies is not specifically related to cagA and multiple EPIYA C repeats.

关键词： Human leukocyte antigen Helicobacter pylori Gastric cancer Duodenal ulcer EPIYA CagA

RISN: An Efficient Sensor Network Overlay with Support for Autonomous and Distributed Applications

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International Journal of Communications, Network and System Sciences 2011年第1期4卷 1-16页

作者： Evens Jean Ingmar Rauschert Robert T. Collins Ali R. Hurson sahra Sedigh Yu Jiao 不详

Once deployed, sensor networks are capable of providing a comprehensive view of their environment. However, since the current sensor network paradigm promotes isolated networks that are statically tasked, the full power of the harnessed data has yet to be exploited. In recent years, users have become mobile enti-ties that require constant access to data for efficient and autonomous processing. Under the current limita-tions of sensor networks, users would be restricted using only a subset of the vast amount of data being col-lected;depending on the networks they are able to access. Through reliance on isolated networks, prolifera-tion of sensor nodes can easily occur in any area that has high appeals to users. Furthermore, support for dy-namic tasking of nodes and efficient processing of data is contrary to the general view of sensor networks as subject to severe resource constraints. Addressing the aforementioned challenges requires the deployment of a system that allows users to take full advantage of data collected in the area of interest to their tasks. Such a system must enable interoperability of surrounding networks, support dynamic tasking, and swiftly react to stimuli. In light of these observations, we introduce a hardware-overlay system designed to allow users to efficiently collect and utilize data from various heterogeneous sensor networks. The hardware-overlay takes advantage of FPGA devices and the mobile agent paradigm in order to efficiently collect and process data from cooperating networks. The computational and power efficiency of the prototyped system are herein demonstrated. Furthermore, as a proof-of-concept, we present the implementation of a distributed and autonomous visual object tracker implemented atop the Reconfigurable and Interoperable Sensor Network (RISN) showcasing the network’s ability to support ad-hoc agent networks dedicated to user’s tasks.

关键词： Pervasive Computing Mobile Computing RISN Service Overlays Overlay Architecture Sensor Network Embedded Systems Mobile Agents Target Tracking Reconfigurable Hardware Interoperability