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THE APPLICATIONS OF A MODIFIED NORMAL FORM APPROACH

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Applied Mathematics and Mechanics(English Edition) 2001年第7期22卷 802-807页

作者：张伟亿 Koncay huseyin 叶敏 Department of Mechanics Tianjin University Tianjin 300072 P R ChinaDepartment of Systems Design Engineering University of Waterloo Waterloo Ontario N2L 3Gl Canada Department of Systems Design Engineering University of Waterloo Waterloo Ontario N2L 3Gl Canada Department of Mechanics Tianjin University Tianjin 300072 P R China

The modified normal form approach presented by ZHANG Wei-yi, K huseyin and CHEN Yu-shu is further extended and a different procedure is introduced which lends itself readily to symbolic calculations, like MAPLE. This provides a number of significant advantages over the previous approach, and facilitates the associated calculations. To illustrate the new approach, three examples are presented.

关键词： nonlinear dynamical system modified normal form approach symbolic calculations

Microstructure,mechanical properties and corrosion resistance of as-cast and as-extruded Mg-4Zn-1La magnesium alloy

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Rare Metals 2020年第8期39卷 909-917页

作者： huseyin Zengin Yunus Turen Hayrettin Ahlatci Yavuz Sun Department of Metallurgy and Materials Engineering Karabuk University78050 KarabukTurkey Iron and Steel Institute Karabuk University78050 KarabukTurkey

Microstructure,mechanical properties and corrosion resistance of as-cast and as-extruded Mg-4 wt%Zn-1 wt%La magnesium alloys were *** alloys were produced by low-pressure die casting method and extruded at 350℃after homogenization at 400℃for 24 *** results show that the as-cast alloy mainly consists of primaryα-Mg matrix and Mg-Zn-La ternary second phases(also called T-Phase)along grain boundaries and isolated spherical particles inside the *** extrusion at350℃,the average grain size decreases by 81%due to dynamic recrystallization mechanism and T-phase particles are distributed along the extrusion *** elongation,yield strength and tensile strength of the as-cast Mg-4Zn-1La alloy increase by 179%,90%and 40%,respectively,as a result of the extrusion *** as-extruded Mg-4Zn-1La alloy shows better corrosion resistance than the as-cast alloy due to increased grain boundaries and decreased content of T-phase.

关键词： Magnesium alloys La modification Extrusion Microstructure Mechanical properties Corrosion

Impact of central venous port implantation method and access choice on outcomes

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World Journal of Clinical Cases 2023年第1期11卷 116-126页

作者： Ayhan Erdemir huseyin Kemal Rasa Department of General Surgery Anadolu Medical CenterKocaeli 41400Turkey Department of General Surgery Anadolu Medical Center HospitalKocaeli 41400Turkey

BACKGROUND Although the number of patients who need central venous ports for permanent vascular access is increasing,there is still no“gold standard”for the implantation *** To identify the implantation technique that should be *** Two hundred central venous port-implanted patients in a tertiary hospital were retrospectively *** were assigned into two groups according to the access *** first group comprised patients whose jugular veins were used,and the second group comprised patients whose subclavian veins were *** were evaluated regarding age,sex,application side,primary diagnosis,active follow-up period in the hospital,chemotherapy agents administered,number of complications,and the Clavien-Dindo severity *** distribution of the variables was tested with the Kolmogorov-Smirnov test and the Mann-Whitney U ***χ^(2) test was used to analyze the *** There was no statistically significant difference between the groups regarding age,sex,side,number of chemotherapy drugs,and duration of port usage(P>0.05).Only 2 patients in group 1 had complications,whereas in group 2 we observed 19 patients with complications(P<0.05).No port occlusion was found in group 1,but the catheters of 4 patients were occluded in group *** port was infected in group 1 compared to three infected ports in group *** port ruptures,two pneumothorax,one revision due to a mechanical problem,one tachyarrhythmia during implantation,and four suture line problems were also recorded in group 2 *** also showed that it would be sufficient to evaluate and wash ports once every 2 *** Our results robustly confirm that the jugular vein route is safer than the subclavian vein approach for central venous port implantation.

关键词： Permanent vascular access Central venous ports Central venous port implantation methods Jugular vein route Subclavian vein approach Impact of implantation method on outcomes

Portopulmonary hypertension in liver transplant candidates

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World Journal of Gastroenterology 2016年第6期22卷 2024-2029页

作者： Serife Savas Bozbas huseyin Bozbas Department of Pulmonary Disease Baskent University Faculty of Medicine06490 AnkaraTurkey Cardiology Clinic Guven Hospital06540 AnkaraTurkey

Pulmonary vascular disorders including portopulmonary hypertension(PoPHT) are among the common complications of liver disease and are prognostically significant. Survival is very low without medical treatment and liver transplantation. With advances in medical therapy for elevated pulmonary artery pressure(PAP) and liver transplant surgery, survival of patients with Po PHT and advanced liver disease is significantly improved. Because of the prognostic significance of Po PHT and the limited donor pool, a comprehensive preoperative cardio-pulmonary assessment is of great importance in cirrhotic patients prior to transplant surgery. Therefore, a detailed transthoracic Doppler echocardiographic examination must be an essential component of this evaluation. Patients with mild Po PHT can safely undergo liver transplant surgery. In cases of moderate to severe Po PHT, right heart catheterization(RHC) should be performed. In patients with moderate to severe Po PHT on RHC(mean PAP 35-45 mm Hg), vasodilator therapy should be attempted. Liver transplantation should be encouraged in cases that demonstrate a positive response. Bridging therapy with specific pulmonary arterial hypertension treatment agents should be considered until the transplant surgery and should be continued during the peri- and post-operative periods as needed.

关键词： portopulmonary hypertension pulmonaryarterial hypertension liver disease liver transplantation portal hypertension

Gastric neuroendocrine neoplasms: A review

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World Journal of Clinical Cases 2021年第27期9卷 7973-7985页

作者： huseyin Koseoglu Tolga Duzenli Mesut Sezikli Department of Gastroenterology Hitit UniversityFaculty of MedicineCorum 19200Turkey Department of Gastroenterology Hitit University Erol Olcok Education and Research HospitalCorum 19200Turkey

Gastric neuroendocrine neoplasms(g-NENs)or neuroendocrine tumors are generally slow-growing tumors with increasing *** arise from enterochromaffin like cells and are divided into four types according to clinical characteristic *** 1 and 2 are gastrin dependent,whereas type 3 and 4 are *** reason for hypergastrinemia is atrophic gastritis in type 1,and gastrin releasing tumor(gastrinoma)in type 2 *** diagnosis of g-NENs needs histopathological investigation taken by upper gastrointestinal endoscopy.g-NENs are positively stained with chomogranin A and *** is made with mitotic index and ki-67 proliferation index on histopathological *** is crucial to discriminate between types of g-NENs,because the management,treatment and prognosis differ significantly between *** options for g-NENs include endoscopic resection,surgical resection with or without antrectomy,medical treatment with somatostatin analogues,netazepide or chemotherapy ***-up without excision is another option in appropriate *** prognosis of type 1 and 2 g-NENs are good,whereas the prognosis of type 3 and 4 g-NENs are close to the prognosis of gastric adenocancer.

关键词： Gastric neuroendocrine tumors Gastric neuroendocrine neoplasm Gastric neuroendocrine carcinoma Hypergastrinemia Carcinoid Somatostatin receptor imaging

Colorectal cancer: The epigenetic role of microbiome

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World Journal of Clinical Cases 2019年第22期7卷 3683-3697页

作者： Hussein Sabit Emre Cevik huseyin Tombuloglu Department of Genetics Institute for Medical Research and Consultations Imam Abdulrahman Bin Faisal University

Colorectal cancer(CRC)is the third most common cancer in men(746000 cases per year)and the second most common cancer in women globally(614000 cases per year).The incidence rate of CRC in developed countries(737000 cases per year)is higher than that in less developed countries(624000 cases per year).CRC can arise from genetic causes such as chromosomal instability and microsatellite *** etiologic factors underlie CRC including age,diet,and *** microbiota represent a proven cause of the disease,where they play pivotal roles in modulating and reshaping the host *** active microbial metabolites have been found to drive carcinogenesis,invasion,and metastasis via modifying both the methylation landscape along with histone structure in intestinal *** microbiota,in response to diet,can exert both beneficial and harmful functions in humans,according to the intestinal balance of number and types of these *** the intestinal microbial community is diverse among individuals,these microbes cumulatively produce 100-fold more proteins than the human genome itself,which calls for further studies to elaborate on the complicated interaction between these microorganisms and intestinal ***,understanding the exact role that gut microbiota play in inducing CRC will help attain reliable strategies to precisely diagnose and treat this fatal disease.

关键词： Colorectal Cancer Colorectal cancer Epigenetics Gut Microbiota

Evolution of Microstructure, Residual Stress, and Tensile Properties of Mg–Zn–Y–La–Zr Magnesium Alloy Processed by Extrusion

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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

Electron beam lithography on nonplanar and irregular surfaces

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Microsystems & Nanoengineering 2024年第2期10卷 1-23页

作者： Chenxu Zhu huseyin Ekinci Aixi Pan Bo Cui Xiaoli Zhu Department of Electrical and Computer Engineering and Waterloo Institute for Nanotechnology(WIN) University of WaterlooWaterlooONCanada

E-beam lithography is a powerful tool for generating nanostructures and fabricating nanodevices with fine features approaching a few nanometers in ***,alternative approaches to conventional spin coating and development processes are required to optimize the lithography procedure on irregular *** this review,we summarize the state of the art in nanofabrication on irregular substrates using e-beam *** overcome these challenges,unconventional methods have been *** instance,polymeric and nonpolymeric materials can be sprayed or evaporated to form uniform layers of electron-sensitive materials on irregular ***,chemical bonds can be applied to help form polymer brushes or self-assembled monolayers on these *** addition,thermal oxides can serve as resists,as the etching rate in solution changes after e-beam ***,e-beam lithography tools can be combined with cryostages,evaporation systems,and metal deposition chambers for sample development and lift-off while maintaining low *** nanopyramids can be fabricated on an AFM tip by utilizing ice as a positive ***,Ti/Au caps can be patterned around a carbon ***,3D nanostructures can be formed on irregular surfaces by exposing layers of anisole on organic ice surfaces with a focused *** advances in e-beam lithography on irregular substrates,including uniform film coating,instrumentation improvement,and new pattern transferring method development,substantially extend its capabilities in the fabrication and application of nanoscale structures.

关键词： lithography beam coating

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World Journal of Gastroenterology 2006年第33期12卷 5379-5383页

作者： Halil Eken Hayrettin Ozturk Hulya Ozturk huseyin Buyukbayram Mardin Children Hospital Department of Pediatric Surgery Diyarbakir Turkey Abanty Izzet Baysal University Medical School Departments of Pediatric Surgery Bolu Turkey Diyarbakir Children Hospital Department of Pediatric Surgery Diyarbakir Turkey Dicle University Medical School Departments of Pathology Diyarbakir Turkey

AIM: To evaluate the effects of dexamethasone on liver damage in rats with bile duct ligation. METHODS: A total of 40 male Sprague-Dawley rats, weighing 165-205 g, were used in this study. Group 1 (sham-control, n = 10) rats underwent laparotomy alone and the bile duct was just dissected from the surrounding tissue. Group 2 rats (untreated, n = 10) were subjected to bile duct ligation (BDL) and no drug was applied. Group 3 rats (low-dose dexa, n = 10) received a daily dose of dexamethasone by orogastric tube for 14 d after BDL. Group 4 rats (high-dose dexa, n = 10) received a daily dose of dexamethasone by orogastric tube for 14 d after BDL. At the end of the two-week period, biochemical and histological evaluations were processed. RESULTS: The mean serum bilirubin and liver enzyme levels signifi cantly decreased, and superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) values were significantly increased in low-dose dexa and high-dose dexa groups when compared to the untreated group. The histopathological score was significantly less in the low-dose and high-dose dexa groups compared to the untreated rats. In the low-dose dexa group, moderate liver damage was seen, while mild liver damage was observed in the high-dose dexa group. CONCLUSION: Corticosteroids reduced liver damage produced by bile duct obstruction. However, the histopathological score was not signifi cantly lower in the high-dose corticosteroid group as compared to the low-dose group. Thus, low-dose corticosteroid provides asignifi cant reduction of liver damage without increased side effects, while high dose is associated not with lower fi brosis but with increased side effects.

关键词： Bile duct ligation Hepatic fibrosis Dexamethasone