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Acta Metallurgica Sinica(English Letters) 2019年第11期32卷 1309-1319页

作者： Huseyin Zengin Yunus Turen Muhammet Emre Turan fatih Ayd?n Department of Metallurgical and Materials Engineering Karabuk University Baliklarkayasi Mevkii Demir Celik Kampusu

The microstructure, texture, residual stress, and tensile properties of Mg–6 Zn–2 Y–1 La–0.5 Zr(wt%) magnesium alloy were investigated before and after extrusion process, which performed at 300 °C and 400 °C. The microstructural characterizations indicated that the as-cast alloy was comprised of α-Mg, Mg–Zn, Mg–Zn–La, and Mg–Zn–Y phases. During homogenization at 400 °C for 24 h, most of the secondary phases exhibited partial dissolution. Extrusion process led to a remarkable grain refi nement due to dynamic recrystallization(DRX). The degree of DRX and the DRXed grain size increased with increasing extrusion temperature. The homogenized alloy did not show a preferential crystallographic orientation, whereas the extruded alloys showed strong basal texture. The extrusion process led to a signifi cant improvement on the compressive residual stress and mechanical properties. The alloy extruded at 300 °C exhibited the highest basal texture intensity, the compressive residual stress and hardness, and yield and tensile strengths among the studied alloys.

关键词： ZK60 Magnesium alloy Residual stress Texture Mechanical properties Extrusion

Combined effects of local curvature and elasticity of an isothermal wall for jet impingement cooling under magnetic field effects

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Journal of Central South University 2021年第11期28卷 3534-3544页

作者： SELİMEFENDİGİL fatih ÇOĞAN Mehmet ÖZTOP Hakan F. Department of Mechanical Engineering Celal Bayar UniversityManisa 45140Turkey Department of Mechanical Engineering Technology FacultyFırat UniversityElazığ23119Turkey

The aim of this study is to examine the effects of local curvature and elastic wall effects of an isothermal hot wall for the purpose of jet impingement cooling *** element method was used with *** important parametric effects such as Re number(between 100 and 700),Ha number(between 0 and 20),elasticity(between 104 and 109),curvature of the surface(elliptic,radius ratio between 1 and 0.25) and nanoparticle volume fraction(between 0 and 0.05) on the cooling performance were investigated *** results showed that the average Nu number enhances for higher Hartmann number,higher values of elastic modulus of partly flexible wall and higher nanoparticle volume *** the magnetic field is imposed at the highest strength,there is an increase of3.85% in the average Nu for the curved elastic wall whereas it is 89.22% for the hot part above it,which is due to the vortex suppression *** inclusion in the base fluid improves the heat transfer rate by about 27.6% in the absence of magnetic field whereas it is 20.5% under the effects of magnetic field at Ha=*** effects become important for higher Re numbers and at Re=700,there is 14.11% variation in the average Nu between the cases with the lowest and highest radius *** elastic wall effects on the heat transfer are reduced with the increased curvature of the bottom wall.

关键词： jet impingement nanoparticles elastic wall MHD CFD curved wall

Treatment of retinopathy of prematurity: a review of conventional and promising new therapeutic options

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 228-236页

作者： fatih Mehmet Mutlu Umit Serdar Sarici Department of Ophthalmology Gülhane Military Medical Academy and Medical School Department of Pediatrics Division of Neonatology Gülhane Military Medical Academy and Medical School

Retinopathy of prematurity (ROP), a retinal vascular disease of premature infants, continues to be a major cause of preventable childhood blindness all over the world. The incidence of ROP varies among countries, being influenced by the quality of the level of neonatal intensive care. Here, we discuss the potential treatments that are now available or will soon or probably be available for ROP. Although ablation of the avascular retina with laser photocoagulation remains the current gold standard and well established therapy for ROP, some new therapeutic options including angiostatic therapies are being explored based on our knowledge of the pathophysiology of the ROP and complications and efficacy of laser treatment. However, prevention of the development of severe ROP and screening for ROP seem to be the best strategy in avoiding visual impairment caused by ROP in premature infants. New therapeutic interventions including vascular endothelial growth factor antibody administration, gene therapy and supplemental therapies should be supported with evidence-based data for the treatment of ROP.

关键词： retinopathy of prematurity laser retina vascular endothelial growth factor propranolol

An Anatomical and Radiological Study of Origins of the Arteries Forming the Celiac Trunk: Clinical and Embryological Implications

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Forensic Medicine and Anatomy Research 2023年第2期11卷 15-29页

作者： Fahrettin fatih Kesmezacar Cem Kopuz Onur Tutar Kubilay Kınoglu Erdoğan kara Vocational School of Health Services Istanbul University-Cerrahpa&#351a Istanbul Turkey Department of Anatomy Medical Faculty Kütahya Health Sciences University Kütahya Turkey Department of Radiology Cerrahpa&#351a Medical Faculty Istanbul University-Cerrahpa&#351a Istanbul Turkey Forensic Medicine Institution Ministry of Justice Istanbul Turkey

The blood supply to the most of abdominal organs is provided by the branches of CT. The SMA supply caecum, ascends colon, all of the small bowels except the upper part of duodenum. Knowledge of variable anatomy of celiac axis and SMA may be useful in planning and executing radiological interventions such as celiacography and chemoembolization of hepatic and pancreatic tumors. In this study, the uncommon or low percentage cases of CT and SMA are presented in the light of clinical and embryological information. The celiac axises of a total of 30 adult corpses were examined. Dissections of abdominal region were performed in detail according to Cunningham’s manual. Angiographic images of 100 consecutive adult patients who underwent celiac MDCT angiography were evaluated. During autopsies, an incomplete celiac trunk or bifurcation of celiac trunk associated with the hepatomesenteric and gastrosplenic trunks (0.7%) and a celiacomesenteric trunk associated with high origin superior mesenteric artery and gastrosplenic trunk were detected (0.7%). During MDCT angiography, a case of total absence of celiac trunk associated with a hepatosplenomesenteric trunk (0.7%) and also a case of total absence of celiac trunk alone were observed (0.7%). The persistence or unusual development of ventral splanchnic arteries (VSAs) or ventral longitudinal anastomosis may result in variations or the unusual trunks related to celiac axis and SMA. The anomalous trunks of the CT may be result of either the persistence of some parts of the VSAs or ventral longitudinal anastomose that normally disappear or disappearance of parts that normally persist. The prevalence of unusual trunks of celiac axis and SMA in this study is quite low in literature. These abnormal vessels pose problems for surgeons and radiologists. Such vascular anomalies may cause clinical complications following surgical and radiological procedures such as resection of tumor of the pancreatic head, lymphadenectomy, coeliacography,

关键词： Celiac Trunk Superior Mesenteric Artery Variation Hepatosplenomesenteric Trunk Celiacomesenteric Trunk Embryology

Higher Order Collocation Methods for Nonlocal Problems and Their Asymptotic Compatibility

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Communications on Applied Mathematics and Computation 2020年第2期2卷 261-303页

作者： Burak Aksoylu fatih Celiker George A.Gazonas CCDC Army Research Laboratory Attn:FCDD-RLW-MBAberdeen Proving GroundAberdeenMD 21005USA Department of Mathematics Wayne State UniversityDetroitMI 48202USA

We study the convergence and asymptotic compatibility of higher order collocation methods for nonlocal operators inspired by peridynamics,a nonlocal formulation of continuum *** prove that the methods are optimally convergent with respect to the polynomial degree of the approximation.A numerical method is said to be asymptotically compatible if the sequence of approximate solutions of the nonlocal problem converges to the solution of the corresponding local problem as the horizon and the grid sizes simultaneously approach *** carry out a calibration process via Taylor series expansions and a scaling of the nonlocal operator via a strain energy density argument to ensure that the resulting collocation methods are asymptotically *** fnd that,for polynomial degrees greater than or equal to two,there exists a calibration constant independent of the horizon size and the grid size such that the resulting collocation methods for the nonlocal difusion are asymptotically *** verify these fndings through extensive numerical experiments.

关键词： Nonlocal operator Inhomogeneous local boundary condition Nonlocal difusion Asymptotic compatibility Collocation method Peridynamics Functional calculus

Tuberculous and non-tuberculous cervical lymphadenopathy incidence and distribution in Somalia from 2016 to 2020:A review of 241 cases

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2022年第4期8卷 361-369页

作者： Mehmet Tahtabasi fatih Sahiner Department of Radiology University of Health Sciences-Somalia Turkey Recep Tayyip Erdogan Education and Research HospitalMogadishuSomalia Department of Medical Microbiology University of Health Sciences-Somalia Turkey Recep Tayyip Erdogan Education and Research HospitalMogadishuSomalia

Objective:To determine the incidence of tuberculous lymphadenitis(TBL)and other pathologies in cervical lymphadenopathies in Somalia and accompanying radiological ***:In this hospital-based retrospective study,the demographic character-istics,pathology results and radiological findings of 263 patients who underwent ultrasound(US)-guided cervical lymph node biopsy between January 2016 and February 2020 were ***:Of 241 patients 118 men and 123 women(mean age 27.9±18.1 years)included in the study,46.1%(n=111)were diagnosed as necrotizing granulomatous lymphadenitis(caseified,consistent with TBL)and 21.6%(n=12,atypical lymphoid cells and n=40,metastases)as *** most common type of metastasis was squamous cell cancer(n=31),and the primary source of most of them was esophageal cancer(16/31,51.6%).The age of patients with TBL was significantly lower than that of non-TBL(21.9±14.6 vs.41.9±24.6,P=0.003)and the incidence of TBL in pediatric patients was statistically higher(58.0%vs.21.5%,P=0.019).The rate of patients with TBL being localized at level 4 and level 5 was significantly more than non-TBL patients(18.0%vs.10.0%and 23.4%vs.10.8%,respectively,P=0.01).Half of patients with TBL who have chest radiography had pathological findings;consolidation and bronchopneumonia were present in 52.6%of *** were 2 patients with paravertebral abscess and one patient with gastrointestinal ***:In Somalia,in the presence of cervical lymphadenopathy,after diagnosis by using US-guided biopsy;primarily considering of TBL and malignancy,thoracic involvement should be investigated,and esophageal carcinoma must be excluded in terms of metastatic lymph node.

关键词： Cervical lymphadenopathy Tuberculosis Tumor metastasis Ultrasound-guided biopsy

Application of ultrasonic waves in measurement of hardness of welded carbon steels

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Defence Technology（防务技术） 2015年第3期11卷 255-261页

作者： fatih UZUN Ali Nezihi BILGE Department of Chemical Engineering Yeditepe University Department of Energy Systems Engineering Bilgi University

The ultrasonic contact impedance technique and ultrasonic wave velocities have been widely used for non-destructive hardness *** wave velocity shift provides through the thickness average hardness, however, the correlations are performed according to surface hardness. In order to accept this technique as a particular non-destructive method for determination of hardness, it is necessary to test it with industrial applications. A widely used joining(welding) technique is selected for this purpose. Samples of carbon steels with three different carbon contents, but similar composition, are annealed in order to obtain the softened samples with different hardness values. Rockwell B scale hardness of heat treated samples, which are assumed to be isotropic, are determined and correlated with ultrasonic wave velocity shifts. Effect of welding process on hardness is investigated using ultrasonic wave velocity shifts, and the results are verified with destructive hardness measurements.

关键词：超声波速度硬度测量焊接工艺工业应用碳钢非破坏性硬度测试接触阻抗

Effect of different heat transfer fluids on discharging performance of phase change material included cylindrical container during forced convection

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Journal of Central South University 2021年第11期28卷 3521-3533页

作者： SELİMEFENDİGİL fatih ŞİRİN Ceylin ÖZTOP Hakan F Department of Mechanical Engineering Manisa Celal Bayar UniversityManisaTurkey Department of Mechanical Engineering Technology FacultyFırat UniversityElazığTurkey

In the present work,effects of various heat transfer fluids on the discharging performance of a phase change material(PCM) included cylindrical container are numerically assessed during forced *** heat transfer fluid air,hydrogen,water and nanofluid with alumina particles are used and the the geometric variation of the PCM embedded region is also *** finite element method is used as the *** features of heat exchange with various phases are explored for different heat transfer fluid types,Reynolds number(between 100 and 300) and PCM embedded region geometric variation(h_(x)between 0.01 d_(1) and 0.65 d_(1),hybetween 0.1 h_(1) and 0.4 h_(1)).It is observed that discharging time is significantly influenced by the heat transfer fluid type while full phase transition time for air is obtained as more than 10 times when hydrogen is utilized as heat transfer *** best performance is achieved with *** the PCM integrated region size is reduced,discharging time is generally reduced while due to the form of the geometry,vortex formation is established in the PCM *** results in performance degeneration at the highest radius and height of the inner *** time increases by about 12% when radius of the inner cylinder is increased from h_(x)=0.35 d_(1) to h_(x)=0.45 d_(1).Dynamic features of PCM temperature and liquid fraction are affected with Reynolds number while discharging time is reduced by about 48% when configurations with the lowest and highest Reynolds number are compared.

关键词： heat transfer fluid hydrogen phase change material finite element method container shape

Dissociation and disasters: A systematic review

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World Journal of Psychiatry 2019年第6期9卷 83-98页

作者： fatih Canan Carol S North The Altshuler Center for Education&Research at Metrocare Services DallasTX 75390United States Department of Psychiatry The University of Texas Southwestern Medical CenterDallasTX 75390United States

BACKGROUND Dissociation,which is defined as the failure to associate consciousness,memory,identity,emotion,perception,body representation,motor control,and behavior into an integrated whole,has long been assumed to be generated by *** dissociation is a product of trauma exposure,then dissociation would be a major mental health outcome observed in studies of disaster *** some studies have examined dissociation in disasters,no systematic literature reviews have been conducted to date on the *** To systematically evaluate the literature on the association between disaster and dissociation to determine the prevalence and incidence of dissociation after exposure to disaster and further examine their *** EMBASE,Medline,and PsychINFO were searched from inception to January 1,2019 to identify studies examining dissociative disorders or symptoms related to a disaster in adult or child disaster survivors and disaster *** of military conflicts and war,articles not in English,and those with samples of 30 or more participants were *** terms used were“disaster*”and dissociation(“dissociat*,”“multiple personality,”“fugue,”“psychogenic amnesia,”“derealization,”and“depersonalization”).Reference lists of identified articles were scrutinized to identify studies for additional *** The final number of articles in the review was 53,including 36 articles with samples of adults aged 18 and above,5 of children/adolescents under age 18,and 12 of disaster *** articles studied several types of disasters that occurred between 1989 and 2017,more than one-third(38%)from the United *** two studies had a primary aim to investigate dissociation in relation to disaster and none reported data on dissociative *** of the studies used self-report symptom scales;none used structured interviews providing full diagnostic assessment of dissociative disorders or other *** stud

关键词： Dissociation Dissociative disorders Disaster Systematic review Methodology Diagnostic validity Psychopathology Normative response Posttraumatic stress Association vs causation

Transgenic mouse models for studying adult neurogenesis

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Frontiers in Biology 2016年第3期11卷 151-167页

作者： fatih Semerci Mirjana Maletic-Savatic Program in Developmental Biology Baylor College of Medicine Houston TX 77030 USA Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital Houston TX 77030 USA Department of Pediatrics-Neurology Department of Neuroscience and Structural and Computational Biology and Molecular Biophysics Baylor College of Medicine Houston TX 77030 USA

The mammalian hippocampus shows a remarkable capacity for continued neurogenesis throughout life. Newborn neurons, generated by the radial neural stem cells （NSCs）, are important for learning and memory as well as mood control. During aging, the number and responses of NSCs to neurogenic stimuli diminish, leading to decreased neurogenesis and age-associatedcognitive decline and psychiatric disorders. Thus, adult hippocampal neurogenesis has garnered significant interest because targeting it could be a novel potential therapeutic strategy for these disorders. However, if we are to use nenrogenesis to halt or reverse hippocampal-related pathology, we need to understand better the core molecular machinery that governs NSC and their progeny. In this review, we summarize a wide variety of mouse models used in adult neurogenesis field, present their advantages and disadvantages based on specificity and efficiency of labeling of different cell types, and review their contribution to our understanding of the biology and the heterogeneity of different cell types found in adult neurogenic niches.

关键词： adult neurogenesis mouse models neural stem cells neuroprogenitors lineage tracing