Browsing by Author "Çelik S."
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Item Determination of synthesis conditions of medium, high, and overbased alkali calcium sulfonate(2007) Beşergil B.; Akin A.; Çelik S.This review covers a method for preparing an overbased detergent-dispersion additive called overbased calcium sulfonate solution (OBCSS) containing 38.9% (w/w) CaCO3, with a total base number (TBN) value of 436 mg KOH, starting from neutral calcium sulfonate solution (NCSS).1,2 After the column conditions were optimized, the reaction parameters (PCO2 and the amounts of Ca(OH)2, water, and monoethanolamine (MEA)) were examined throughout the tests. The first product medium alkali calcium sulfonate solution (MACSS) with 8.5% (w/w) CaCO3 (TBN = 95 mg KOH/g) is obtained, but higher base values could not be reached. In the second stage, monoethanolamine is added to the feed as a promoter and high alkali calcium sulfonate solution (HACSS) containing 30.4% (w/w) CaCO3 with the value of TBN = 274 mg KOH/g is obtained. In the third stage of the study, targeted product OBCSS is obtained by using HACSS as a feedstock component instead of NCSS. © 2007 American Chemical Society.Item Determination of fermentation and digestibility characteristics of corn, sunflower and combination of corn and sunflower silages(2008) Demirel M.; Bolat D.; Çelik S.; Bakici Y.; Eratak S.This study was conducted to determine in vivo digestibilities and fermentation property of various silages made of green herbage of Sunflower (SF), Corn (C) and corn-sunflower mixtures at different rates [75% corn+25% sunflower (75C25SF), 50% corn+50% sunflower (50C50SF), 25% corn+75 sunflower (25C75SF)] ensiled in 120 1 plastic barrels for 90 days. PH values of C and mixture silages were lower than that of SF silage (p<0.05). Concentrations of lactic, acetic, propionic and butyric acids were higher in SF silage than C silage (p<0.05). Lactic and propionic acid concentrations increased in mixture silages as the sunflower ratio increased, whereas decreases in butyric acid concentration were observed as corn ratio incresed in the mixture (p<0.05). While digestibility of DM, OM, ADF and NDF were high in C silage, digestibility of CP and EE were high in SF silage. The digestibility of DM, OM, ADF and NDF in mixture silages increased with the increases in corn ratio in mixture and digestibility of CP and EE of increased as sunflower ratio increased in mixture. It can be concluded that high quality silages could be obtained from green herbage of corn or sunflower alone, however their nutritive values could be improved if they are mixed at 50% ratio. © Medwell Journals, 2008.Item Effect of various additives and harvesting stages on rumen degradation of sunflower silages(2009) Demirel M.; Bolat D.; Eratak S.; Çelik S.; Bakici Y.; Çelik S.; Güney M.To study effective degradability (nylon bag technique) of sunflower silage, as influenced by harvesting stage (blooming, milk or dough) or molasses (m) I urea (u) mixture, seven different silage samples for each harvest stage [sunflower (SF) and 6 mixtures (2%mSF, 4%mSF, 2%m+0.5%uSF, 2%m+1%uSF, 4%m+0.5%uSF, 4%m+1%uSF)] were incubated for 70 days in 1 litter jars. The DM and CP effective degradation of SF silage was found to be similar at blooming and milking stage and higher than that of dough stage (P<0.05). The effective degradation of ADF and NDF of SF silage at milking and dough stages was lower than that of blooming stage. The positive effects of molasses and molasses+urea additives on effective degradability were observed. It was concluded that decreased degradability of nutrient matters because of its advanced vegetational stage could be partly compensated by using different amount of molasses and molasses+urea additives. © GSP, India.Item A retrospective evaluation of the epithelial changes/lesions and neoplasms of the Gallbladder in Turkey and a review of the existing sampling methods: A multicentre study(Federation of Turkish Pathology Societies, 2018) Esendağli G.; Akarca F.G.; Balci S.; Argon A.; Şengiz Erhan S.; Turhan N.; İnce Zengin N.; Hallaç Keser S.; Çelik B.; Bulut T.; Abdullazade S.; Erden E.; Savaş B.; Bostan T.; Sağol Ö.; Aysal Ağalar A.; Kepil N.; Karslioğlu Y.; Günal A.; Markoç F.; Saka B.; Özgün G.; Özdamar Ş.O.; Bahadır B.; Kaymaz E.; Işık E.; Ayhan S.; Tunçel D.; Özgüven Yılmaz B.; Çelik S.; Karabacak T.; Erbarut Seven İ.; Ataizi Çelikel Ç.; Gücin Z.; Ekinci Ö.; Akyol G.Objective: As there is continuing disagreement among the observers on the differential diagnosis between the epithelial changes/lesions and neoplasms of the gallbladder, this multicentre study was planned in order to assess the rate of the epithelial gallbladder lesions in Turkey and to propose microscopy and macroscopy protocols. Material and Method: With the participation of 22 institutions around Turkey that were included in the Hepato-Pancreato-Biliary Study Group, 89,324 cholecystectomy specimens sampled from 2003 to 2016 were retrospectively evaluated. The numbers of adenocarcinomas, dysplasias, intracholecystic neoplasms/adenomas, intestinal metaplasias and reactive atypia were identified with the review of pathology reports and the regional and countrywide incidence rates were presented in percentages. Results: Epithelial changes/lesions were reported in 6% of cholecystectomy materials. Of these epithelial lesions, 7% were reported as adenocarcinoma, 0.9% as high-grade dysplasia, 4% as low-grade dysplasia, 7.8% as reactive/regenerative atypia, 1.7% as neoplastic polyp, and 15.6% as intestinal metaplasia. The remaining lesions (63%) primarily included non-neoplastic polypoids/hyperplastic lesions and antral/pyloric metaplasia. There were also differences between pathology laboratories. Conclusion: The major causes of the difference in reporting these epithelial changes/lesions and neoplasms include the differences related to the institute’s oncological surgery frequency, sampling protocols, geographical dissimilarities, and differences in the diagnoses/interpretations of the pathologists. It seems that the diagnosis may change if new sections are taken from the specimen when any epithelial abnormality is seen during microscopic examination of the cholecystectomy materials. © 2018, Federation of Turkish Pathology Societies. All rights reserved.Item Corporate governance and performance(IGI Global, 2019) Çelik S.; Güleç T.C.The purpose of the present study is to evaluate the current state of the linkage between corporate governance and performance. Corporate governance is by far the most important subject that should be studied due to its role and significance. Accordingly, there is intensive literature on corporate governance and its possible impact on performance. By conducting a systematic literature review, the authors provide the results of frequently used variables that supposed to reflect the character of corporate governance on firm performance. The study covers the findings of empirical papers that analyze the impact of 'board size,' 'percentage of independent directors,' 'CEO duality,' 'ownership concentration,' 'audit committee and auditor reputation,' 'board meetings,' and 'firm size.' The examination of the reviewed studies indicates that there is a need to explain the competing findings observed among firms, markets, and countries by developing a theoretical explanation. © 2020, IGI Global. All rights reserved.Item What we learned about COVID-19 so far? Notes from underground(AVES, 2020) Akyıl F.T.; Karadoğan D.; Gürkan C.G.; Yüksel A.; Arıkan H.; Eyüboğlu T.Ş.; Emiralioğlu N.; Gürsoy T.R.; Şerifoğlu İ.; Töreyin Z.N.; Marim F.; Kara B.Y.; Özakıncı H.; Develi E.; Çakmakçı S.; Küsbeci T.Ç.; Karcıoğlu O.; Gülhan P.Y.; Erçelik M.; Er B.; Ataoğlu Ö.; Polat D.; Kaya İ.; Önyılmaz T.A.; Aydın A.; Kızılırmak D.; Er A.B.; Kılınç M.; Günaydın F.E.; Gürz S.; Karaoğlanoğlu S.; Çelik S.; Esendağlı D.; Toptay H.; Sertçelik Ü.Ö.; Akgün M.The novel coronavirus pandemic poses a major global threat to public health. Our knowledge concerning every aspect of COVID-19 is evolving rapidly, given the increasing data from all over the world. In this narrative review, the Turkish Thoracic Society Early Career Taskforce members aimed to provide a summary on recent literature regarding epidemiology, clinical findings, diagnosis, treatment, prevention, and control of COVID-19. Studies revealed that the genetic sequence of the novel coronavirus showed significant identity to SARS-CoV and MERS-CoV. Angiotensin-converting enzyme 2 receptor is an important target of the SARS-CoV-2 while entering an organism. Smokers were more likely to develop the disease and have a higher risk for ICU admission. The mean incubation period was 6.4 days, whereas asymptomatic transmission was reported up to 25 days after infection. Fever and cough were the most common symptoms, and cardiovascular diseases and hypertension were reported to be the most common comorbidities among patients. Clinical manifestations range from asymptomatic and mild disease to severe acute respiratory distress syndrome. Several patients showed typical symptoms and radiological changes with negative RT-PCR but positive IgG and IgM antibodies. Although radiological findings may vary, bilateral, peripherally distributed, ground-glass opacities were typical of COVID-19. Poor prognosis was associated with older age, higher Sequential Organ Failure Assessment score, and high D-dimer level. Chloroquine was found to be effective in reducing viral replication in vitro. Likewise, protease inhibitors, including lopinavir/ritonavir, favipiravir, and nucleoside analogue remdesivir were proposed to be the potential drug candidates in COVID-19 management. Despite these efforts, we still have much to learn regarding the transmission, treatment, and prevention of COVID-19. © 2020 by Turkish Thoracic Society.Item Sextant Biopsy-Based Criteria for Clinically Insignificant Prostate Cancer Are Also Valid for the 12-Core Prostate Biopsy Scheme: A Multicenter Study of Urooncology Association, Turkey(S. Karger AG, 2022) Çelik S.; Klzllay F.; Yörükoǧlu K.; Aslan G.; Ozen H.; Akdogan B.; Sozen S.; Baltaci S.; Muezzinoglu T.; Izol V.; Bayazlt Y.; Narter F.; Türkeri L.Background: Epstein criteria based on sextant biopsy are assumed to be valid for 12-core biopsies. However, very scarce information is present in the current literature to support this view. Objectives: To investigate the validity of Epstein criteria for clinically insignificant prostate cancer (PCa) in a cohort of the currently utilized 12-core prostate biopsy (TRUS-Bx) scheme in patients with low-risk and intermediate-risk PCa. Method: Pathological findings were separately evaluated in the areas matching the sextant biopsy (6-core paramedian) scheme and in all 12-core schemes. Patients were divided into 2 groups according to the final pathology report of RP as true clinically significant PCa (sPCa) and insignificant PCa (insPCa) groups. Predictive factors (including Epstein criteria) and cutoff values for the presence of insPCa were separately evaluated for 6- and 12-core TRUS-Bx schemes. Then, different predictive models based on Epstein criteria with or without additional biopsy findings were created. Results: A total of 442 patients were evaluated. PSA density, biopsy GS, percentage of tumor and number of positive cores, PNI, and HG-PIN were independent predictive factors for insPCa in both TRUS-Bx schemes. For the 12-core scheme, the best cutoff values of tumor percentage and number of positive cores were found to be ≤50% (OR: 3.662) and 1.5 cores (OR: 2.194), respectively. The best predictive model was found to be that which added 3 additional factors (PNI and HG-PIN absence and number of positive cores) to Epstein criteria (OR: 6.041). Conclusions: Using a cutoff value of "1"for the number of positive biopsy cores and absence of biopsy PNI and HG-PIN findings can be more useful for improving the prediction model of the Epstein criteria in the 12-core biopsy scheme. © 2021 Authors.Item ERS International Virtual Congress 2021: Highlights from the Turkish Thoracic Society Early Career Members(AVES, 2022) Yumrukuz Şenel M.; Karadoğan D.; Vardaloğlu I.; Develi E.; Çelik S.; Hızal M.; Özseren B.; Öncel A.; Can İ.; Hürsoy N.; Uyar K.; Karakaş F.G.; Er B.; Asfuroğlu P.; Gürsoy T.R.; Eyüboğlu T.Ş.; Çakır E.P.; Ademhan D.; Karaoğlanoğlu S.; Emiralioğlu N.; Öztürk N.A.A.; Marim F.; Güçlü Ö.A.; Çetin N.; Topçu D.Ö.; Çelik P.; Akgün M.This review aimed to highlight some important points derived from the presentations of the European Respiratory Society 2021 Virtual International Congress by a committee formed by the Early Career Task Group of the Turkish Thoracic Society. We summarized a wide range of topics including current developments of respiratory diseases and provided an overview of important and striking topics of the congress. Our primary motivation was to give some up-to-date information and new developments discussed during congress especially for the pulmonologists who did not have a chance to follow the congress. This review also committed an opportunity to get an overview of the newest data in the diverse fields of respiratory medicine such as post-coronavirus disease 2019, some new interventional and technologic developments related to respiratory health, and new treatment strategies. © Author(s).Item The Effect of a Training Video With Audio Description on the Breast Self-Examinations of Women With Visual Impairments(SAGE Publications Ltd, 2023) Çelik S.; Çalım S.İ.Introduction: Breast cancer is a significant health problem affecting the health of women globally. Breast self-examination is a procedure applied for the early detection of breast cancer. Given the barriers that women with visual impairments face to access health care and health education, there is a need to develop materials for breast self-examination training as a skills-based practice for this group. This study evaluated the effect of a training video with an audio description on the breast self-examination of women who were visually impaired. Methods: The universe of this quasi-experimental study comprised women who were visually impaired (N = 70) who were registered members of the Manisa Altinokta Blind Association in Turkey. The women who participated in the study volunteered and met the selection criteria (n = 60). They were divided into two groups by lot. The audio description group listened to a breast self-examination training video with an audio description (n = 30). The control group listened to the training video accompanied by typical sound, without audio description (n = 30). Before and after a training video, all women performed breast self-examination on a female mannequin torso. The skills of women in breast self-examination were evaluated using a checklist by a midwife who was non-researcher. Results: The skills differed significantly between the two groups after the video training (p < 0.05). The audio description group correctly performed most of the skills required for breast self-examination. None of the women in the groups were able to apply steps for such self-examination before the training. Discussion: A breast self-examination training video with audio description can improve the self-examination skills of women with visual impairments. Implications for Practitioners: Women with visual impairments benefit from watching a breast self-examination training video with an audio description before performing self-examinations. Training videos with audio descriptions should, therefore, be prepared for the health education of individuals who are visually impaired. © American Foundation for the Blind 2023.