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International Journal of Sediment Research 2011年第2期26卷 247-249页

作者： o.yagci U.TURKER Istanbul Technical University Civil Engineering FacultyDivision of Hydraulics Near East University Civil Engineering DepartmentDivision of Hydraulics

We discussants appreciate the authors’ investigation on the impacts of the vegetated channel walls and aspect ratio on flow velocity profiles,shear stress distribution and roughness coefficient of *** primary aim of this comment is to emphasize some of the points which were not considered by the authors during their *** discussers would like to mention the following points regarding the paper. The expression of "wall vegetation" is a new term for the current *** the researchers have not given enough explanation about *** is "wall vegetation"?Where can we observe wall-vegetation in nature?What are the characteristic species as "wall-vegetation"?We think that the clarification of this point will significantly improve the benefit of this study.

关键词： Discussion on by Hossein Afzalimehr,Jueyi Sui and Razieh Moghbel[Int.J.Sed.Res Hydraulic parameters in channels with wall vegetation and gravel bed

Mechanistic Transformations Involving Radical and Cationic Polymerizations

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Chinese Journal of Polymer Science 2020年第3期38卷 205-212,I0004页

作者： Gorkem Yilmaz Yusuf yagci Istanbul Technical University Department of ChemistryMaslak34469 IstanbulTurkey Center of Excellence for Advanced Materials Research(CEAMR)and Department of Chemistry Faculty of ScienceKing Abdulaziz University21589 JeddahSaudi Arabia

Mechanistic transformation approach has been widely applied in polymer synthesis due to its unique feature combining structurally different polymers prepared by different polymerization *** methods for the formation of block and graft copolymers through mechanistic transformation involve almost all polymerizations ***,certain polymerization processes require extensive purification processes,which can be time-consuming and *** developments on controlled/living polymerizations involving radical and cationic mechanisms with the ability to control molecular weight and functionality led to new pathways for mechanistic *** this mini-review,we systematically discussed relevant advances in the field through three main titles namely(i)from radical to cationic mechanism,(ii)from cationic to radical mechanism,and(iii)application of specific catalyst systems for both radical and cationic polymerizations.

关键词： Transformation Radical polymerization Cationic polymerization Controlled/living polymerization Photopolymerization

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A PURCHASING DECISIoN: SELECTING A SUPPLIER FoR A CoNSTRUCTIoN CoMPANY

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Journal of Systems Science and Systems Engineering 2006年第2期15卷 217-231页

作者： ozden BAYAZIT Birsen KARPAK Ayhan yagci Department of Business Administration Central Washington UniversityUSA Department of Management Youngstown State UniversityUSA3Social Sciences InstituteAnkara UniversityTurkey Social Sciences Institute Ankara UniversityTurkey

Supplier selection is one of the most crucial activities performed by organizations because of its strategic importance. Supplier selection is a multi-objective problem involving both quantitative and qualitative criteria. over the years a number of quantitative approaches have been tried. Although the Analytic Hierarchy Process （AHP） has previously been used in supplier selection problems, one major weakness of the application-oriented AHP literature is that it tends to focus on the mechanics of AHP instead of on the theoretical and practical implications associated with finding a solution. Though it is one of the most extensively used Multiple Criteria Decision Analysis methodologies, our literature search indicated that most studies found the best solution and stopped there, ignoring sensitivity analysis. Performing sensitivity analysis is very important for practical decision making, sometimes even as important as finding the best solution. In this paper for the first time a comprehensive application of AHP for a real-world case is presented along with sensitivity analysis in choosing the best suppliers for a Turkish construction company. As a result of this study the company decided to allocate the order quantities between the two top suppliers.

关键词： Vendor Selection Analytic Hierarchy Process Multicriteria Decision Making

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Influence of surface roughness of dune bedforms on flow and turbulence characteristics

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International Journal of Sediment Research 2020年第6期35卷 666-678页

作者： Veysel Sadan ozgur Kirca Seyed Mahdi Saghebian Kiyoumars Roushangar oral yagci Istanbul Technical University Department of Civil Engineering Department of Civil Engineering Ahar Branch Islamic Azad University Division of Hydraulics Department of Civil EngineeringUniversity of Tabriz

The current paper investigates the flow and turbulence characteristics over dune bedforms by means of laboratory experiments,where spatially dense and temporally high frequency velocity measurements were *** similar studies are available in the literature,the focus and novelty of the current study is to assess the influence of surface roughness of the dune bedforms on the nearbed *** direct comparison,two different surface roughness heights over idealized,fixed-shaped,high-angled dune bedforms were tested;one with a hydraulically-smooth surface,and the other with a fully-rough *** variation of time-averaged flow as well as turbulence statistics were examined,which was complemented by streamline plots and spectral *** results are interpreted from sediment entrainment and sediment transport points of *** results show that increased dune surface roughness reduces the nearbed flow velocity,but increases the flow velocities at upper *** upward directed flow near the dune crests becomes stronger in the case of smooth surface,while the reattachment point moves further downstream compared to the rough wall *** is concluded that the roughness of the dune surface affects the nearbed flow and turbulence characteristics qualitatively and quantitatively,which is shown to have direct consequences on sediment entrainment characteristics.

关键词： Bedforms Dunes Friction drag Turbulence Grain roughness Form drag

Effects of primary selective laser trabeculoplasty on anterior segment parameters

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International Journal of ophthalmology(English edition) 2015年第5期8卷 954-959页

作者： Suzan Guven Yilmaz Melis Palamar Emil Yusifov Halil Ates Sait Egrilmez Ayse yagci Department of ophthalmology Faculty of MedicineEge University

AIMTo investigate the effects of selective laser trabeculoplasty (SLT) on the main numerical parameters of anterior segment with Pentacam rotating Scheimpflug camera in patients with ocular hypertension (oHT) and primary open angle glaucoma (PoAG).METHoDSPentacam measurements of 45 eyes of 25 (15 females and 10 males) patients (12 with oHT, 13 with PoAG) before and after SLT were obtained. Measurements were taken before and 1 and 3mo after SLT. Pentacam parameters were compared between oHT and PoAG patients, and age groups (60y and older, and younger than 60y).RESULTSThe mean age of the patients was 57.8±13.9 (range 20-77y). Twelve patients (48%) were younger than 60y, while 13 patients (52%) were 60y and older. Measurements of pre-SLT and post-SLT 1mo were significantly different for the parameters of central corneal thickness (CCT) and anterior chamber volume (ACV) (Po pre-SLT values at post-SLT 3mo. Decrease of ACV at post-SLT 1mo was significantly higher in younger than 60y group than 60y and older group. There was no statistically significant difference in Pentacam parameters between oHT and PoAG patients at pre- and post-treatment measurements (P>0.05).CoNCLUSIoNSLT leads to significant increase in CCT and decrease in ACV at the 1st month of the procedure. Effects of SLT on these anterior segment parameters, especially for CCT that interferes IoP measurement, should be considered to ensure accurate clinical interpretation.

关键词： anterior segment selective laser trabeculoplasty Pentacam

Phenolic compounds affect production of pyocyanin, swarming motility and biofilm formation of Pseudomonas aeruginosa

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 698-701页

作者： Aylin Ugurlu Aysegul Karahasan yagci Seyhan Ulusoy Burak Aksu Gulgun Bosgelmez-Tinaz Department of Microbiology School of Medicine Marmara University Department of Biology Faculty of Arts and Sciences Süleyman Demirel University Department of Basic Pharmaceutical Sciences Faculty of Pharmacy Marmara University

objective: To investigate the effects of plant-derived phenolic compounds(i.e. caffeic acid, cinnamic acid, ferulic acid and vanillic acid) on the production of quorum sensing regulated virulence factors such as pyocyanin, biofilm formation and swarming motility of Pseudomonas aeruginosa(P. aeruginosa) ***: Fourteen clinical P. aeruginosa isolates obtained from urine samples and P. aeruginosa PA01 strain were included in the study. The antibacterial effects of phenolic compounds were screened by well diffusion assay. Pyocyanin and biofilm activity were measured from culture supernatants and the absorbance values were measured using a spectrophotometer. Swarming plates supplemented with phenolic acids were point inoculated with P. aeruginosa strains and the ability to swarm was determined by measuring the distance of swarming from the central inoculation ***: Tested phenolic compounds reduced the production of pyocyanin and biofilm formation without affecting growth compared to untreated cultures. Moreover, these compounds blocked about 50% of biofilm production and swarming motility in P. aeruginosa ***: We may suggest that if swarming and consecutive biofilm formation could be inhibited by the natural products as shown in our study, the bacteria could not attach to the surfaces and produce chronic infections. Antimicrobials and natural products could be combined and the dosage of antimicrobials could be reduced to overcome antimicrobial resistance and drug side effects.

关键词： Quorum sensing Phenolic compounds Pseudomonas aeruginosa Biofilm Swarming

Accurate positioning of the 24-hour pH monitoring catheter:Agreement between manometry and pH step-up method in two patient positions

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World Journal of Gastroenterology 2007年第46期13卷 6197-6202页

作者： Mehmet Fatih Can Gokhan yagci Sadettin Cetiner Mustafa Gulsen Taner Yigit Erkan ozturk Semih Gorgulu Turgut Tufan Departments of General Surgery Gulhane Military Medical AcademyEtlikAnkaraTurkey "Reflux Research Group"Gulhane Military Medical AcademyEtlikAnkaraTurkey Gastoenterology and Hepatology Gulhane Military Medical AcademyEtlikAnkaraTurkey "Reflux Research Group"Gulhane Military Medical AcademyEtlikAnkaraTurkey Departments of General Surgery Gulhane Military Medical AcademyEtlikAnkaraTurkey

AIM： To investigate the agreement between esophageal manometry and pH step-up method in two different patient positions. METHoDS： Eighteen subjects were included in the study. First, the distance from the nose to the proximal border of the lower esophageal sphincter （LES） was measured manometrically. Then a different investigator, who was blinded to the results of the first study, measured the same distance using the pH step-up method, with the patient in both upright and supine positions. An assessment of agreement between the two techniques was performed. RESULTS： In the supine position, the measurement of only one subject was outside the range accepted for correct positioning （~〈 3 cm distal or proximal to the LES）. In the upright position, errors in measurement were recognized in five subjects. Bland-Airman plots revealed good agreement between measurements obtained manometrically and by the pH-step up method with the patient in the supine position. CoNCLUSIoN： In the case of nonavailability of manometric detection device, the pH step-up method can facilitate the positioning of the 24 h pH monitoring catheter with the patient in the supine position. Thisshould increase the use of pH-metry in clinical practice for subjects with suspected gastroesophageal reflux disease if our results are supported by further studies.

关键词： pH monitoring Esophageal manometry pHstep-up method Gastroesophageal reflux

Differences between radiological findings of CoVID-19 and non-CoVID-19 infections in pediatric patients

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World Journal of Pediatrics 2021年第1期17卷 79-84页

作者： Beyza Nur Kuzan Bülent Aslan Taha Yusuf Kuzan Aysegül Karahasan yagci Nuri Cagatay Cimsit Department of Radiology Marmara University School of MedicineIstanbul 34899Turkey Department of Radiology Sancaktepe Sehit Dr.Ilhan Varank Training and Research HospitalIstanbul 34785Turkey Department of Clinical Microbiology Marmara University School of MedicineIstanbul 34899Turkey

Background This study aimed to reveal the differences between coronavirus disease 2019(CoVID-19)infections and non-CoVID-19 respiratory tract infections in pediatric *** Sixty pediatric patients admitted to the hospital between March 11,2020 and April 15,2020 with respiratory tract infections were evaluated *** them,20 patients with reverse transcription-polymerase chain reaction(RT-PCR)tests and chest computed tomography(CT)examinations were included in the *** to the RT-PCR test results,the patients were divided into the CoVID-19 and non-CoVID-19 *** clinical observations,laboratory results,and radiological features from the two groups were then *** According to the RT-PCR test results,12 patients were assigned to the CoVID-19 group and 8 to the non-CoVID-19 *** were no significant differences between the two groups in terms of clinical or laboratory *** terms of radiological features,the presence of bronchiectasis and peribronchial thickening was statistically significantly higher in the non-CoVID-19 group(P=0.010 and P=0.010,respectively).Conclusions In pediatric cases,diagnosing CoVID-19 using radiological imaging methods plays an important role in deter-mining the correct treatment approach by eliminating the possibility of other infections.

关键词： Chest imaging Computerized tomography CoVID-19 Pediatric Pneumonia

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World Journal of Gastroenterology 2010年第14期16卷 1765-1771页

作者： zcan eneli Zübeyde Nur zkurt Kadir Acar Seyyal Rota Sahika Zeynep Aki Zeynep Arzu Yegin Münci yagci Seren zenirler Gülsan Türkz Sucak Department of Hematology Gazi University Faculty of Medicine Besevler 06500 Ankara Turkey Department of Microbiology Gazi University Faculty of Medicine Besevler 06500 Ankara Turkey Department of Gastroenterology Gazi University Faculty of Medicine Besevler 06500 Ankara Turkey

AIM: To investigate the frequency of occult hepatitis B, the clinical course of hepatitis B virus (HBV) reactivation and reverse seroconversion and associated risk factors in autologous hematopoietic stem cell transplantation (HSCT) recipients. METHoDS: This study was conducted in 90 patients undergoing autologous HSCT. occult HBV infection was investigated by HBV-DNA analysis prior to transplantation, while HBV serology and liver function tests were screened prior to and serially after transplantation. HBV-related events including reverse seroconversion and reactivation were recorded in all patients. RESULTS: None of the patients had occult HBV prior to transplantation. Six (6.7%) patients were positivefor HBV surface antigen (HBsAg) prior to transplantation and received lamivudine prophylaxis; they did not develop HBV reactivation after transplantation. Clinical HBV infection emerged in three patients after transplantation who had negative HBV-DNA prior to HSCT. Two of these three patients had HBV reactivation while one patient developed acute hepatitis B. Three patients had anti-HBc as the sole hepatitis B-related antibody prior to transplantation, two of whom developed hepatitis B reactivation while none of the patients with antibody to HBV surface antigen (anti-HBs) did so. The 14 anti-HBs-and/or anti-HBc-positive patients among the 90 HSCT recipients experienced either persistent (8 patients) or transient (6 patients) disappearance of anti-HBs and/or anti-HBc. HBsAg seroconversion and clinical hepatitis did not develop in these patients. Female gender and multiple myeloma emerged as risk factors for loss of antibody in regression analysis (P oNCLUSIoN: Anti-HBc as the sole HBV marker seems to be a risk factor for reactivation after autologous HSCT. Lamivudine prophylaxis in HbsAg-positive patients continues to be effective.

关键词： Autologous stem cell transplantation Hepatitis B reactivation occult hepatitis Multiple mye- loma Lymphoma

Early endoscopic retrograde cholangiopancreatography after laparoscopic cholecystectomy can strain the occurrence of trocar site hernia

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World Journal of Gastrointestinal Endoscopy 2014年第11期6卷 568-570页

作者： Fatih Sumer Cuneyt Kayaalp Mehmet Ali yagci Emrah otan Huseyin Kocaaslan Department of Surgery Inonu Uni-versity Malatya 44315 Turkey

This study reports a 69-year-old, obese, female patientpresenting with a biliary leakage after laparoscopiccholecystectomy for cholelithiasis. Closure of the um-bilical trocar site had been neglected during the lapa-roscopic cholecystectomy. Early, on postoperative dayfive, endoscopic retrograde cholangiopancreatography(ERCP) requirement after laparoscopic cholecystectomyresolved the biliary leakage problem but resulted with amore complicated clinical picture with an intestinal ob-struction and severe abdominal pain. Computed tomog-raphy revealed a strangulated hernia from the umbilicaltrocar site. Increased abdominal pressure during ERCPhad strained the weak umbilical trocar site. Emergencysurgical intervention through the umbilicus revealed anischemic small bowel segment which was treated withresection and anastomosis. This report demonstratesthat negligence of trocar site closure can result in veryearly herniation, particularly if an endoscopic interven-tion is required in the early postoperative period.

关键词： Laparoscopic cholecystectomy Trocar site hernia Endoscopic retrograde cholangiopancreatogra-phy Postoperative complications