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Evaluation of ischemic lesions after carotid artery stenting with diffusion-weighted imaging

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World Journal of Clinical Cases 2020年第10期8卷 1859-1870页

作者： Murat Beyhan Berat Acu Erkan Gokce mehmet Murat firat Department of Radiology Tokat Gaziosmanpasa University Faculty of MedicineTokat 60100Turkey Department of Radiology Eskisehir Osmangazi University Faculty of MedicineEskisehir 26480Turkey Department of Radiology Guven HospitalAnkara 06540Turkey

BACKGROUND Almost 90%of cerebral thromboembolism cases are caused by *** atherosclerosis is often observed at the carotid bifurcation and is responsible for 20%-30%of all stroke *** course of atherosclerotic carotid artery stenosis varies depending on the grade of stenosis and characteristics of the *** artery stenting(CAS)can be used as a less invasive method in patients with symptomatic and asymptomatic high-grade carotid artery ***-weighted imaging(DWI)is an effective method for detection of silent or symptomatic acute ischemic lesions that may arise due to CAS or carotid *** number and volume of new ischemic lesions are determined using *** To evaluate the number and volume of ischemic lesions and their cerebral parenchymal and vascular distribution after CAS using *** Forty-seven male(73.4%)and seventeen female(26.6%)patients(total,n=64)aged 42-84 years(mean 67.96±8.03 years)diagnosed with carotid stenosis between October 2006 and July 2012 were included in this retrospective *** of the cases(18.8%)were asymptomatic,while fifty-two(81.2%)were *** area where the stenosis was highest was measured,and the stenosis rate was determined using the North American Symptomatic Carotid Endarterectomy Trial *** of the cases was evaluated by two radiologists experienced in neuroradiology(*** more than 15 years of experience,*** more than 10 years of experience).Routine DWI examinations were carried out by a 1.5 T MR device 1 h before and after the *** the ischemic lesions that developed in the first hour and in the follow-up period of 5-24 h were assumed to be due to CAS,all lesions within the first 24 h were considered as new *** In the present study,39 new ischemic lesions were detected in 20 *** average number of new lesions after all CAS operations was *** were mostly located in the occipital lobes,followed by

关键词： Carotid artery stenosis Carotid artery stenting Diffusion-weighted imaging Ischemia Stroke

Robust Backstepping Control of a Quadrotor Unmanned Aerial Vehicle under Colored Noises

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Computers, Materials & Continua 2025年第1期82卷 777-798页

作者： mehmet Karahan Electrical and Electronic Engineering Department Atilim UniversityAnkara06830Turkey

Advances in software and hardware technologies have facilitated the production of quadrotor unmanned aerial vehicles(UAVs).Nowadays,people actively use quadrotor UAVs in essential missions such as search and rescue,counter-terrorism,firefighting,surveillance,and cargo *** performing these tasks,quadrotors must operate in noisy ***,a robust controller design that can control the altitude and attitude of the quadrotor in noisy environments is of great *** researchers have focused only on white Gaussian noise in their studies,whereas researchers need to consider the effects of all colored noises during the operation of the *** study aims to design a robust controller that is resistant to all colored ***,a nonlinear quadrotormodel was created with ***,a backstepping controller resistant to colored noises was *** backstepping controller was tested under Gaussian white,pink,brown,blue,and purple *** and Lyapunov-based controller designswere also carried out,and their time responses(rise time,overshoot,settling time)were compared with those of the backstepping *** the simulations,time was in seconds,altitude was in meters,and roll,pitch,and yaw references were in *** and settling time values were in seconds,and overshoot value was in *** the obtained values are examined,simulations prove that the proposed backstepping controller has the least overshoot and the shortest settling time under all noise types.

关键词： Backstepping control colored noises Gaussian noise Lyapunov stability quadrotor robustness PID control

Detection of class 1 integron in Acinetobacter baumannii isolates collected from nine hospitals in Turkey

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Asian Pacific Journal of Tropical Biomedicine 2013年第9期3卷 743-747页

作者： Aysegül Copur Cicek Azer Ozad Düzgün Aysegül Saral Tuba Kayman Zeynep Cizmeci Pervin Ozlem Balci Tuba Dal mehmet firat Ismail Tosun Yasemin Ay Alitntop Ahmet Caliskan Yelda Yazici Cemal Sandalli Department of Medical Microbiology Faculty of MedicineRecep Tayyip Erdogan University Department of Genetics and Bioengineering Faculty of Engineering and Natural SciencesGümüshane University Department of Biology Faculty of Arts and SciencesArtvin Coruh University Clinical Microbiology Laboratory Research and Training Hospital Clinical Microbiology Laboratory Kecioren Research and Training Hospital Clinical Microbiology Laboratory General State Hospital Department of Medical Microbiology Faculty of MedicineDicle University Clinic of Infectious Diseases and Clinical Microbiology PrivateOSM Ortadogu Hospital Microbiology Laboratory Kirikkale Highly Specialized Hospital General State Hospital Microbiology Laboratory Necip Fazil City Hospital Clinical Microbiology Laboratory Ahi Evren Chest and Cardiovascular Surgery Research and Training Hospital Department of Biology Faculty of Arts and SciencesRecep Tayyip Erdogan University

Objective:To investigate the antibiotic resistance genes inserted into class I and class 2integrons in Acinetobacler baumannii[***)isolates obtained from nine different cities in ***:A collection of 281 *** clinical isolates were collected from nine diferenl state hospitals in Turkey and were confirmed as *** by conventional biochemical,API testing and bla_(-OXA-51)specific *** isolates were examined by PCR for existence of class I and2 integron gene ***:They were characterized by antimicrobial susceptibility testing and the highest resistance rates were determined for piperacillin(90.03%),ciprofloxacin(87.54%),cefepime and trimethoprim/sulfamethoxazole(81.13%).The lowest resistance rates was for cefotaxime(3.55%).class 1 integrons were detected in 6.4%(18/281)of *** strains and no class 2 integron was *** gene casselles of class 1 inlegrons AacCI-AAC(3)l-aadAI,AacCI-aadA1,AAC(3)-I,AAC(3)-I-AAC(3)-I-aadA1,***(3)-I-aadA1-AAC(3)-I-AAC(3)-I,AAC(3)-I-AAC(3)-I-AAC(3)-I-aadA1,AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I,AAC(3)-I-aadA1-AAC(3)-I-aadA1,AAC(3)-I-AAC(3)-I-aadA1-AAC(3)-I-aadA1 were detected in eighteen *** aac genes family were most frequently found integrated into the class 1 inlegrons and it was followed by aadA genes and TEM-1 ***:This is an extensive study on the distribulion of class 1 integron among *** in *** addition to these,two new alleles were *** percentage rates of similarity to other cassettes are 95%aadA1(TK A18)and 89%,aadA 1(ANKA3).

关键词： Acinetobacter baumannii Class 1 integron Gene cassette Resistance

Screening of Class 1 and Class 2 Integrons in Clinical Isolates of Pseudomonas aeruginosa Collected from Seven Hospitals in Turkey:A Multicenter Study

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Open Journal of Medical Microbiology 2013年第4期3卷 227-233页

作者： Aysegul Copur Cicek Aysegul Saral Azer Ozad Duzgun Zeynep Cizmeci Tuba Kayman Pervin Ozlem Balci Tuba Dal mehmet firat Yelda Yazici Metin Sancaktar Osman Birol Ozgumus Cemal Sandalli Department of Medical Microbiology Faculty of MedicineRecep Tayyip Erdogan UniversityRizeTurkey Department of Biology Faculty of Arts and SciencesArtvin Coruh UniversityArtvinTurkey Department of Genetics and Bioengineering Faculty of Engineering and Natural SciencesGumushane UniversityGumushaneTurkey Clinical Microbiology Laboratory Kecioren Research and Training HospitalAnkaraTurkey Clinical Microbiology Laboratory Research and Training HospitalKayseriTurkey Clinical Microbiology Laboratory General State HospitalTokatTurkey Department of Medical Microbiology Faculty of MedicineDicle UniversityDiyarbakirTurkey Clinic of Infectious Diseases and Clinical Microbiology Private OSM Ortadogu HospitalSanliurfaTurkey Clinical Microbiology Laboratory Ahi Evren Chest and Cardiovascular Surgery Research and Training HospitalTrabzonTurkey Clinical Microbiology Laboratory Akcaabat Hackali Baba General State HospitalTrabzonTurkey Department of Biology Faculty of Arts and SciencesRecep Tayyip Erdogan UniversityRizeTurkey

Pseudomonas aeruginosa is one of the leading nosocomial pathogens worldwide, and their infections are difficult to treat due to acquired resistance to many antibiotics. This study aimed to detect class 1 and 2 integrons and antibiotic susceptibility of clinical isolates of P. aeruginosa. Two hundred and five P. aeruginosa strains were collected from the seven general state hospitals in Turkey. They were characterized by antimicrobial susceptibility testing, screened for class 1 and class 2 integrons, and evaluated for the association between antibiotic resistance phenotypes and the presence of integrons. intI gene was amplified in 10 isolates (4.87%) by PCR and in seven isolates of them (70%) were found different gene cassettes. The aadA gene integrated into the class 1 integrons was most frequently found and it was followed by aac genes and blaOXA family genes. Sequence analysis of variable regions of the class 1 integrons showed five gene cassette arrays;aadA1(99%), aac(3)-Id(82%)-orf-aac(3”)-Ia(99%), aac(3)-Ie(83%)-blaoxa10(100%)- aadA1 (100%), aadA6(99%, 100%), aac(6’)-I(97%)-orf-aadA2(99%). No class 2 integron was detected. This study is the first multicenter study for class 1 integrons and it indicates the low rate of presence of class 1 gene cassette in P. aeruginosa.

关键词： Pseudomonas aeruginosa Antibiotic Resistance Class 1 Integron AadA Multicenter Study

Incidence and clinical presentation of portal vein thrombosis in cirrhotic patients

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Hepatobiliary & Pancreatic Diseases International 2016年第5期15卷 499-503页

作者： Yasir Furkan Cagin Yahya Atayan mehmet Ali Erdogan firat Dagtekin Cemil Colak Division of Gastroenterology Medical Faculty Inonu University Malatya 44280 Turkey Division of Internal Medicine Medical Faculty Inonu University Malatya 44280 Turkey Division of Biostatistics and Medical Informatics Colak C Medical Faculty Inonu University Malatya 44280 Turkey

BACKGROUND: Portal vein thrombosis (PVT) is due to many risk factors, but its pathogenesis is still not clearly understood. To identify the risk factors for PVT, we analyzed the clinical characteristics and complications associated with PVT in cir-rhotic patients. METHODS: We studied patients with liver cirrhosis who were admitted to our unit from April 2009 to December 2014. The patients were divided into the PVT and non-PVT groups, and were compared by variables including gender, age, the etiology of cirrhosis, stage of cirrhosis, complications, imaging, and treatment. RESULTS: PVT was found in 45 (9.8%) of 461 cirrhotic pa-tients admitted to our hospital. Most patients (45.9%) had hepatitis B virus (HBV)-related cirrhosis, with a similar dis-tribution of etiologies between the groups. However, there was no positive relationship between PVT and etiologies of cirrhosis. Most patients (71.5%) were in the stage of hepatic decompensation. No statistically signiifcant differences were found in complications including esophageal varices, ascites, and hepatic encephalopathy between the groups. However, there was a signiifcant positive correlation between hepatocel-lular carcinoma (HCC) and PVT (P CONCLUSIONS: The incidence of PVT was 9.8%, mainly in patients with HBV-related cirrhosis. The development of PVT was associated with the severity of liver disease and HCC.

关键词： portal vein thrombosis cirrhosis clinical presentation

Fuzzy rule based seismic risk assessment of one-story precast industrial buildings

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Earthquake Engineering and Engineering Vibration 2019年第3期18卷 631-648页

作者： mehmet Palanci Istanbul Arel University Department of Civil Engineering

Effi cient tools capable of using uncertain data to produce fast and approximate results are more practical in rapid decision-making applications when compared to conventional methods. From this point of view, this study introduces a risk assessment model for one-story precast industrial buildings by fuzzy logic which builds a bridge between uncertainty and precision. The input, output and relations of the fuzzy based risk assessment model (FBRAM) were determined by reference buildings. The Monte Carlo simulation method was used to handle uncertainties associated with the structural characteristics of the reference buildings. Section dimension, longitudinal reinforcement ratio, column height related to building elevation, confi nement ratio and seismic hazard are regarded as input and the plastic demand ratio is considered as the output parameter by the mathematical formulation of strength and deformation capacity of the buildings. The supervised learning method was used to determine the membership function of fuzzy sets. Fuzzy rules of FBRAM were constructed from Monte Carlo simulation by mapping of inputs and output. FBRAM was evaluated by a group of simulated buildings and two existing precast industrial buildings. Comparisons have shown signifi cant agreement with analytical model results in both cases. Consequently, it is anticipated that the proposed model can be used for the seismic risk mitigation of precast buildings.

关键词： fuzzy logic supervised learning precast buildings risk assessment Monte Carlo simulation

Two-and three-dimensional stability analysis of underground storage caverns in soft rock(Cappadocia, Turkey) by finite element method

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Journal of Mountain Science 2022年第4期19卷 1182-1202页

作者： SARI mehmet Department of Mining Engineering Aksaray UniversityAksaray 68100Turkey

Engineering design in soft rocks and its stability analysis exerts many challenges to rock engineers. Many engineering works in Turkey’s Cappadocia region must face and tackle the existing sites covered by the soft rocks. This study is aimed to examine the stability condition of a typical underground storage cavern(USC) excavated in a soft rock in this region. For this purpose, two-and threedimensional stability analyses of the USCs were performed using the finite element method(FEM).Because of the inherent difficulty in characterizing soft/weak rock masses in the region using traditional classification systems, the stability of a typical USC was evaluated by representing the rock mass condition with two distinct scenarios in FEM *** these structures were unstable according to the 2D analysis conducted in RS2 software in the worstcase scenario, they were stable in the 3D analysis using RS3 software in both scenarios. Besides,feasible cover depths were examined to assess their possible effects on the factor of safety and deformation measurements. It was found that 15 m seems to be an optimal depth for excavating a typical USC in the soft rocks exposed in the region. The 3D FEM results provide valuable information to optimize the future planning and preliminary design of USCs.

关键词： Underground storage cavern Numerical modeling Soft rock FEM analysis Rock mass failure

Evaluating rockfalls at a historical settlement in the Ihlara Valley(Cappadocia, Turkey) using kinematic, numerical, 2D trajectory, and risk rating methods

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Journal of Mountain Science 2022年第12期19卷 3346-3369页

作者： SARI mehmet Department of Mining Engineering Aksaray UniversityAksaray68100Turkey

Rockfalls are one of the most dangerous natural events in hilly terrains, and they substantially threaten residential areas and transport corridors in these environments. This study is aimed to analyze the risk of rockfall from a slope to nearby houses in a historical settlement with past rockfall histories. It contains numerous applications to study rockfall danger from different points of view(e.g., kinematics,numerical stability analysis, risk assessment, 2D trajectory). The rockfall kinematics revealed the statistics for different structurally controlled failure modes among the surveyed slope discontinuities,especially wedge type and block toppling were the most significant ones. Finite element analysis showed that the slope was stable under the natural condition with a safety factor of 2.19. The rockfall risk rating system calculated a medium risk for the houses downstream. Based on the field measurements, a possible rockfall profile was determined and located as an input in the 2D rockfall trajectory program. The rigid-body impact model runs utilized various shapes and sizes of blocks to simulate the rockfall events realistically. According to the 2D trajectory model results, there was no rockfall danger for the investigated downslope houses. The study showed the importance of using different analysis techniques to solve rockfall risk in protected areas based on scientific and rational approaches.

关键词： Belisirma village Cappadocia region Rockfall kinematics 2D rockfall trajectory analysis Rockfall risk rating system FEM modeling

Analytical and approximate solutions of(2+1)-dimensional time-fractional Burgers-Kadomtsev-Petviashvili equation

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Communications in Theoretical Physics 2020年第5期72卷 21-31页

作者： mehmet Senol Department of Mathematics Nevsehir Haci Bektas Veli UniversityNevsehirTurkey

In this paper,we applied the sub-equation method to obtain a new exact solution set for the extended version of the time-fractional Kadomtsev-Petviashvili equation,namely Burgers-Kadomtsev-Petviashvili equation(Burgers-K-P)that arises in shallow water ***,using the residual power series method(RPSM),approximate solutions of the equation were obtained with the help of the Mathematica symbolic computation *** also presented a few graphical illustrations for some *** fractional derivatives were considered in the conformable *** of the obtained solutions were replaced back in the governing equation to check and ensure the reliability of the *** numerical outcomes confirmed that both methods are simple,robust and effective to achieve exact and approximate solutions of nonlinear fractional differential equations.

关键词： fractional partial differential equations Burgers-Kadomtsev-Petviashvili equation conformable fractional derivative sub-equation method residual power series method