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Accuracy of urea breath test in Helicobacter pylori infection: Meta-analysis

World Journal of Gastroenterology 2015年第4期21卷 1305-1314页

作者： Mazen Ferwana Imad Abdulmajeed Ali Alhajiahmed Wedad Madani Belal Firwana Rim Hasan Osama Altayar Paul J Limburg mohammad hassan murad Bandar Knawy National and Gulf Center for Evidence-Based Health Practice King Saud Bin Abdulaziz University for Health SciencesRiyadh 11426Saudi Arabia Department of Medicine University of Missouri ColumbiaMissouriMO 65211United States Knowledge and Evaluation Research Unit Mayo ClinicRochesterMN 65212United States Knowledge and Evaluation Research Unit Mayo ClinicRochesterMN 55905United States Department of Internal Medicine Allegheny General HospitalPittsburgPA 55905United States Division of Gastroenterology Mayo ClinicRochesterMN 55905United States Division of Preventive Medicine Mayo ClinicRochesterMN 55905United States

AIM: To quantitatively summarize and appraise the available evidence of urea breath test(UBT) use to diagnose Helicobacter pylori(H. pylori) infection in patients with dyspepsia and provide pooled diagnostic accuracy ***: We searched MEDLINE, EMBASE, Cochrane library and other databases for studies addressing the value of UBT in the diagnosis of H. pylori infection. We included cross-sectional studies that evaluated the diagnostic accuracy of UBT in adult patients with dyspeptic symptoms. Risk of bias was assessed using QUADAS(Quality Assessment of Diagnostic Accuracy Studies)-2 tool. Diagnostic accuracy measures were pooled using the random-effects model. Subgroup analysis was conducted by UBT type(13C vs 14C) and by measurement technique(Infrared spectrometry vs Isotope Ratio Mass Spectrometry).RESULTS: Out of 1380 studies identified, only 23 met the eligibility criteria. Fourteen studies(61%) evaluated 13 C UBT and 9 studies(39%) evaluated 14 C UBT. There was significant variation in the type of reference standard tests used across *** sensitivity was 0.96(95%CI: 0.95-0.97) andpooled specificity was 0.93(95%CI: 0.91-0.94). Likelihood ratio for a positive test was 12 and for a negative test was 0.05 with an area under thecurve of 0.985. Meta-analyses were associated with a significant statistical heterogeneity that remained unexplained after subgroup analysis. The included studies had a moderate risk of ***: UBT has high diagnostic accuracy for detecting H. pylori infection in patients with dyspepsia. The reliability of diagnostic meta-analytic estimates however is limited by significant heterogeneity.

关键词： Helicobacter pylori Dyspepsia Breath tests Urea/an

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Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks

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Computers, Materials & Continua 2025年第1期82卷 1151-1169页

作者： Khalil Ullah Song Jian Muhammad Naeem Ul hassan Suliman Khan mohammad Babar Arshad Ahmad Shafiq Ahmad Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Department of Computer Science Abbottabad University of Science and TechnologyHavelianAbbottabad22500Pakistan Department of Computing and Electronics Engineering Middle East CollegeMuscat124Oman Department of CS&IT Pak-Austria Fachhochschule Institute of Applied Sciences and Technology MangHaripur22621Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityRiyadh11421Saudi Arabia

The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile *** networks are sufficiently scaled to interconnect billions of users and *** in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous *** continuously improves its network functionality to support these *** input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in *** article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial *** technique aims to create long-lasting and secure NextG networks using this extended *** viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this ***,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques.

关键词： Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security

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GRADE指南：Ⅵ.证据质量评价--不精确性(随机误差)

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中国循证医学杂志 2011年第12期11卷 1435-1443页

作者： Gordon Guyatt Andrew D.Oxman Regina Kunz Jan Brozek Pablo Alonso-Coello David Rind PJ Devereaux Victor M.Montori Bo Freyschuss Gunn Vist Roman Jaeschke John W.Williams Jr. mohammad hassan murad David Sinclairk Yngve Falck-Ytter Joerg Meerpohl Craig Whittington Kristian orlund Je Andrews Holger J.Schünemann 代表GRADE工作组李幼平王莉陈尹高霑机构不详

GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健... 详细信息

GRADE建议通过检查95%可信区间(CI)为决定不精确性的最佳方法。在指南实际运用中,如果CI的上、下限值代表了真实效应,而临床实际情况与之不符时,必须降低证据质量级别(即对效应估计值的把握度)。除外当效应值很大且可信区间提示效应稳健,而总样本量不大且事件数很少的情况,其他应考虑因不精确性而降低证据质量级别。作此决定时,可计算有足够检验效能的单个试验所需的病例数(定义为"最优信息样本量",即optimal information size,OIS)。对连续型变量,我们建议用类似方法,首先考虑可信区间上、下限值,再计算OIS。系统评价(SR)所需方法略有不同。如果95%CI不包括相对危险度(RR)为1,且总事件发生数或病例数超过OIS标准,则精确性良好。如果95%CI包括了明显获益或危害(我们建议以RR值1.25作粗标准),即使达到OIS要求,因不精确性而降低证据质量级别较恰当。

关键词： GRADE 证据质量估计值把握度不精确性最优样本信息量可信区间

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Engendered nanoparticles for treatment of brain tumors

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Oncology Research 2025年第1期33卷 15-26页

作者： SOROUSH SOLEYMANI mohammad DOROUDIAN MAHDIEH SOEZI ALI BELADI KIARASH ASGARI ASO MOBARAKSHAHI ARYANA AGHAEIPOUR RONAN MACLOUGHLIN Department of Cell and Molecular Biology School of Biological SciencesUniversity of LeicesterLeicesterLE17RHUK Department of Cell and Molecular Biology Faculty of Biological SciencesKharazmi UniversityTehran15719-14911Iran Cancer Epidemiology Research Center Aja University of Medical SciencesTehran14117-18541Iran Medical Biotechnology Research Center Aja University of Medical SciencesTehran14117-18541Iran Department of Life Sciences Faculty of Natural SciencesImperial College LondonLondonSW72AZUK School of Pharmacy and Biomolecular Sciences Royal College of Surgeons in Ireland(RCSI)DublinD02 YN77Ireland Research and Development Science and Emerging TechnologiesAerogen Ltd.Galway Business ParkGalwayH91 HE94Ireland School of Pharmacy and Pharmaceutical Sciences Trinity CollegeDublinD02 PN40Ireland

Brain metastasis and primary glioblastoma multiforme represent the most common and lethal malignant brain *** median survival time is typically less than a year after *** of the major challenges in treating these cancers is the efficiency of the transport of drugs to the central nervous *** blood-brain barrier is cooperating with advanced stages of *** blood-brain barrier poses a significant challenge to delivering systemic medications to brain *** delivery systems have emerged as promising tools for effectively crossing this ***,the development of smart nanoparticles brings new hope for cancer diagnosis and *** nanoparticles improve drug delivery efficiency,allowing for the creation of targeted and stimuli-responsive delivery *** review highlights recent advancements in nanoparticle and smart nanoparticle technologies for brain cancer treatment,exploring the range of nanoparticles under development,their applications,targeting strategies,and the latest progress in enhancing transport across the blood-brain *** also addresses the ongoing challenges and potential benefits of these innovative approaches.

关键词： Nanoparticles Smart nanoparticles Stimuli responsive nanoparticles Targeted nanoparticles Blood-brain barrier(BBB) Brain cancer

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Liquation cracking in the heat-affected zone of IN939 superalloy tungsten inert gas weldments

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 764-773页

作者： hassan Kazempour-Liasi mohammad Tajally hassan Abdollah-Pour Faculty of Materials and Metallurgical Engineering Semnan UniversitySemnanIran

The main aim of this study was to investigate liquation cracking in the heat-affected zone(HAZ)of the IN939 superalloy upon tungsten inert gas welding.A solid solution and age-hardenable filler metals were further *** the pre-weld heat-treated samples,upon solving the secondaryγ′particles in the matrix,primaryγ′particles in the base metal grew to"ogdoadically diced cubes"of about 2μm in side *** pre-weld heat treatment reduced the hardness of the base metal to about HV *** studies using optical and fieldemission scanning electron microscopy revealed that the IN939 alloy was susceptible to liquation cracking in the *** constitutional melting of the secondary,eutectic,and Zr-rich phases promoted the liquation cracking in the *** microstructure of the weld fusion zones showed the presence of fine spheroidalγ′particles with sizes of about 0.2μm after the post-weld heat treatment,which increased the hardness of the weld pools to about HV 350 and 380 for the Hastelloy X and IN718 filler metals,*** of a suitable solid solution filler metal could partially reduce the liquation cracking in the HAZ of IN939 alloy.

关键词： superalloy tungsten inert gas weld heat-affected zone liquation cracking

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A novel technology for control of variable speed pumped storage power plant

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Journal of Central South University 2016年第8期23卷 2008-2023页

作者： Seyed mohammad hassan Hosseini mohammad Reza Semsar Department of Electrical Engineering Islamic Azad University

Variable speed pumped storage machines are used extensively in wind power plant and pumped storage power plant. This paper presents direct torque and flux control(DTFC) of a variable speed pumped storage power plant(VSPSP). By this method both torque and flux have been applied to control the VSPSP. The comparison between VSPSP's control strategies is studied. At the first, a wind turbine with the capacity 2.2 k W and DTFC control strategies simulated then a 250 MW VSPSP is simulated with all of its parts(including electrical, mechanical, hydraulic and its control system) by MATLAB software. In all of simulations, both converters including two-level voltage source converter(2LVSC) and three-level voltage source converter(3LVSC) are applied. The results of applying 2LVSC and 3LVSC are the rapid dynamic responses with better efficiency, reducing the total harmonic distortion(THD) and ripple of rotor torque and flux.

关键词： direct torque and flux control(DTFC) two-level & three-level voltage source converter(2LVSC&3LVSC) variable speed pumped storage power plant(VSPSP)

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Mass and performance optimization of an airplane wing leading edge structure against bird strike using Taguchi-based grey relational analysis

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Chinese Journal of Aeronautics 2016年第4期29卷 934-944页

作者： hassan Pahange mohammad Hossein Abolbashari Department of Mechanical Engineering Ferdowsi University of Mashhad Department of Mechanical Engineering Lean Production Engineering Research Center Ferdowsi University of Mashhad

Collisions between birds and aircraft are one of the most dangerous threats to flight safety. In this study, smoothed particles hydrodynamics(SPH) method is used for simulating the bird strike to an airplane wing leading edge structure. In order to verify the model, first, experiment of bird strike to a flat aluminum plate is simulated, and then bird impact on an airplane wing leading edge structure is investigated. After that, considering dimensions of wing internal structural components like ribs, skin and spar as design variables, we try to minimize structural mass and wing skin deformation simultaneously. To do this, bird strike simulations to 18 different wing structures are made based on Taguchi’s L18 factorial design of experiment. Then grey relational analysis is used to minimize structural mass and wing skin deformation due to the bird strike. The analysis of variance(ANOVA) is also applied and it is concluded that the most significant parameter for the performance of wing structure against impact is the skin thickness. Finally, a validation simulation is conducted under the optimal condition to show the improvement of performance of the wing structure.

关键词： Bird strike Grey relational analysis Multi-objective optimization Smooth particle hydrody namics(SPH) Wing leading edge structure

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Nonsingular terminal sliding mode approach applied to synchronize chaotic systems with unknown parameters and nonlinear inputs

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Chinese Physics B 2012年第6期21卷 107-116页

作者： mohammad Pourmahmood Aghababa hassan Feizi Electrical Engineering Department Urmia University of TechnologyUrmiaIran Department of Mathematics Mamaghan BranchIslamic Azad UniversityMamaghanIran

This paper deals with the design of a novel nonsingular terminal sliding mode controller for finite-time synchro-nization of two different chaotic systems with fully unknown parameters and nonlinear inputs. We propose a novel nonsingular terminal sliding surface and prove its finite-time convergence to zero. We assume that both the master＇s and the slave＇s system parameters are unknown in advance. Proper adaptation laws are derived to tackle the unknown parameters. An adaptive sliding mode control law is designed to ensure the existence of the sliding mode in finite time. We prove that both reaching and sliding mode phases are stable in finite time. An estimation of convergence time is given. Two illustrative examples show the effectiveness and usefulness of the proposed technique. It is worthwhile noticing that the introduced nonsingular terminal sliding mode can be applied to a wide variety of nonlinear control problems.

关键词： nonsingular terminal sliding mode finite-time synchronization uncertain parameter,nonlinear input

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Elastic Mechanical Stress Analysis in a 2D-FGM Thick Finite Length Hollow Cylinder with Newly Developed Material Model

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Acta Mechanica Solida Sinica 2016年第2期29卷 178-191页

作者： Amir Najibi mohammad hassan Shojaeefard Faculty of Mechanical Engineering Semnan University School of Mechanical Engineering Iran University of Science & Technology

In this paper a new 2D-FGM material model based on Mori-Tanaka scheme and third-order transition function has been developed for a thick hollow cylinder of finite *** mechanical stress analysis is performed by utilizing the finite element *** corresponding material,displacement and stress distributions are evaluated for different values of nr and ***,the effects of different material property distributions on the effective stress with respect to the metallic phase volume fraction are *** is demonstrated that the increase in nr and V_m leads to a significant reduction in the effective ***,it is shown that the ceramic phase rich cylinder wall has lower maximum effective stresses of which the lowest value of effective stress has been evaluated for nr=20 and nz=*** minimum value is about half the maximum effective stress which has been evaluated for the non-FGM cylinder case（nr=nz=0.1）.

关键词： 2D-FGM elastic analysis thick hollow cylinder Mori-Tanaka material model

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Aerodynamic investigation of twist angle variation based on wing smarting for a flying wing

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Chinese Journal of Aeronautics 2021年第2期34卷 201-216页

作者： Ruhollah KARIMI KELAYEH mohammad hassan DJAVARESHKIAN Department of Mechanical Engineering Ferdowsi University of MashhadMashhadIran

In this paper, the effects of twist angle variation on aerodynamic coefficients and flow field on the wing with wing smarting approach are studied using numerical simulation. The simulation was performed using incompressible Reynolds-Averaged Navier-Stokes(RANS) equations based on the two-equation k-x Shear Stress Transport(SST) turbulent model for flow speed30 m/s and a Reynolds number of 69000. Investigations have been carried out for several twist angles and at a specific range of angles of attack. The twist applied is the type of geometric twist(wash-out), which is linearly distributed along the span. The test case is a lambda-shaped tailless aircraft with a wing fracture on the trailing edge, and a sweep angle 56°. The results show that with increasing twist angle, the aerodynamic efficiency improves over a wide range of angles of attack,but at 0° angle of attack it will decrease significantly. By increasing the angle of attack, the effect of twist on the flow field and aerodynamic coefficients will gradually decrease;hence, at a certain amount of angle of attack, the effect of twist will stop, that angle is called the neutral brink *** stability analysis shows that by growing the twist angle, the conditions required for longitudinal stability are satisfied, and the pitch-up phenomenon will be delayed.

关键词： Aerodynamics Flying wing Twist Wing smarting Numerical simulation

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