Uludag University Academic Repository
Not a member yet
50710 research outputs found
Sort by
Microstructural evolution and mechanical performance of dual-phase steels under fiber laser welding: Effects of heat input and weld penetration
No full textThis study investigates the effects of fiber laser welding (FLW) parameters on the microstructural evolution and mechanical properties of DP800, DP1000, and DP1200 dual-phase steels, focusing on the role of heat input. Welding was performed using laser powers ranging from 1500 to 3000 W and welding speeds between 20 and 100 mm/s, resulting in heat inputs from 18 to 120 J/mm. Optimal welding conditions were identified as 55 J/mm for DP800, 120 J/mm for DP1000, and 53 J/mm for DP1200, which ensured full penetration and minimized HAZ softening. Detailed microstructural analysis using SEM and EBSD revealed significant transformations in the heat-affected zone (HAZ), including martensite degradation, grain coarsening, and tempered martensite formation, particularly in DP1200 steel, where hardness reductions reached up to 29%. Tensile tests demonstrated that while DP800 and DP1000 joints primarily failed within the base material (BM) with ductile fracture characteristics, DP1200 joints fractured within the HAZ due to a combination of brittle cleavage and ductile dimples caused by martensite breakdown and carbide precipitation. The findings underscore the necessity of optimizing welding parameters to control HAZ softening and preserve mechanical performance. By systematically analyzing the interplay between heat input, microstructure, and mechanical properties across different DP steel grades, this research provides a comprehensive understanding of how FLW conditions influence joint integrity, offering valuable guidance for designing robust welding strategies in advanced engineering applications
The effect of posture and breathing exercises applied with telerehabilitation on respiratory functions, exercise capacity, fatigue, and psychosocial factors in chronic obstructive pulmonary disease patients
No full textObjective This study aims to examine the effects of telerehabilitation, including posture and breathing exercises, on respiratory functions, quality of life, exercise capacity, fatigue, and psychosocial factors in individuals with chronic obstructive pulmonary disease (COPD). Methods Thirty individuals diagnosed with COPD (15 in the control group, 15 in the treatment group) were randomly selected for the study. Participants were evaluated through a pulmonary function test, dyspnea, health-related quality of life, exercise capacity, fatigue, psychosocial factors. Posture and breathing exercises were applied to the treatment group via video conference for a total of 16 sessions, 45 min, 2 days/week, for 8 weeks. Results When the pre-and post-treatment data were compared in fatigue, depression, and anxiety examinations, the change in the treatment group was found to be statistically significant (p < 0.05). Conclusion It was concluded that exercise with telerehabilitation in COPD patients is effective on quality of life, exercise capacity, fatigue, psychosocial factors and can be used as a treatment approach. Clinical Trial Number NCT0487957
Insulins
No full textIn healthy individuals, insulin secretion from the pancreatic beta cells (endogenous) varies throughout the day according to plasma glucose concentration and the behavior of hormones acting on glucose metabolism. By dividing and examining endogenous insulin secretion into two periods, prandial and basal secretions, the insulin treatments for type 2 diabetes mellitus (T2DM) can be determined. Prandial secretion: Rapid and peak insulin secretion (prandial/bolus secretion) in the pancreas in the prandial/early postprandial period prevents postprandial blood glucose from rising above physiological limits. In treating T2DM patients requiring insulin therapy, rapid/shortacting insulins are administered for prandial secretion. Prandial insulin doses consist of two components: insulin (feeding dose) required to keep glucose elevations within physiological limits after meals and insulin needed to correct if the glucose level detected before meals is higher than the target (correction dose). Basal secretion: Non-peaked secretion (basal secretion) regulates hepatic glucose production and glucose metabolism in skeletal muscle and fatty tissues and controls blood glucose levels during fasting periods. In treating T2DM patients who require insulin therapy, medium/long/very long acting insulins are administered for basal secretion. In this section, different insulins used for the treatment of diabetes will be discussed
A retrospective analysis of the inadequacy of tracheostomy decannulation under single-stage endoscopic guidance in ıntansive care patient
No full textAmaç: Yoğun bakım tedavisi sırasında trakeostomi uygulanan hastaların, endoskopi rehberliği ile dekanülasyonu sonrası erken dönemde görülen problemleri ve dekanülasyon yetersizliğine neden olan etmenlerin ve başarısının araştırılmasını amaçladık. Metod: Etik kurul onayı alındıktan sonra Ocak 2004-Aralık 2024 tarihleri arasında üniversite hastanemizin tıbbi yoğun bakım ünitesine kabul edilen ve sonrasında kliniğimizde trakeostomi açılan, tedavisi sonrası endoskopik muayene ile değerlendirilip, dekanülasyon kararı verilen hastalar retrospektif olarak incelendi. Rekanülasyon ile ilişkili faktörleri belirlemek amacıyla, bağımlı değişken olarak rekanülasyon alınarak çok değişkenli lojistik regresyon analizi uygulandı. Bulgular: Yoğun bakımda trakeostomize takip ettiğimiz 1557 hastadan dekanülasyon kriterlerini karşılayan 308 hastaya endoskopik muayene uygulandı ve 216 hasta muayene sonrası dekanüle edildi ve 92 hasta endoskopik muayenede dekanülasyona uygun bulunmadı. Dekanüle edilen 10 hasta sonrasında rekanüle/reentübe edildi ve başarısız dekanülasyonun en sık sebebi artmış sekresyon olarak bulundu. Sonuç: Endoskopik muayenenin, havayolunun bütünlüğünün değerlendirilmesinde etkili olduğu ve dekanülasyon sonrası gelişecek komplikasyonları azalttığı görülmüş olup, dekanülasyon öncesi endoskopik muayenenin rutin bir uygulama haline getirilmesi gerektiği düşüncesindeyiz. Özellikle yoğun bakım hastalarında dekanülasyon sonrası yoğun bakımlarda en az 24 saat gözlenmesi uygun olacağı görüşündeyiz.Objective: We aimed to investigate the early postoperative problems observed after endoscopic-guided decannulation in patients who underwent tracheostomy during intensive care treatment, as well as the factors contributing to decannulation failure and the success rate of the procedure. Methods: After obtaining approval from the ethics committee, a retrospective analysis was conducted on patients who were admitted to the medical intensive care unit of our university hospital between January 2004 and December 2024, underwent tracheostomy in our clinic, and were evaluated by endoscopic examination following treatment and subsequently deemed eligible for decannulation. To identify factors associated with recannulation, multivariable logistic regression analysis was performed using recannulation as the dependent variable. Results: Among 1,557 tracheostomized patients monitored in the intensive care unit, 308 patients who met the decannulation criteria underwent endoscopic examination. Of these, 216 patients were decannulated following the examination, while 92 patients were deemed unsuitable for decannulation based on the endoscopic findings. Among the decannulated patients, 10 required recannulation or reintubation. The most common cause of failed decannulation was found to be increased airway secretions. Conclusion: Endoscopic examination was found to be effective in evaluating airway integrity and in reducing post-decannulation complications. iv We believe that routine endoscopic evaluation should be adopted as a standard practice prior to decannulation. In particular, we recommend that intensive care patients be monitored in the ICU for at least 24 hours following decannulation
Hydrogen fuel cell vehicles: Overview and current status of hydrogen mobility
No full textThis study explores the potential of hydrogen in transportation systems, analyzing recent developments and trends in hydrogen fuel cell vehicles (HFCVs). The study focuses on the role of individual components in enhancing the vehicle's functionality and performance. A comprehensive comparative analysis is conducted, evaluating HFCVs against internal combustion engine, plug-in hybrid electric, and battery electric vehicles across several critical factors such as driving range, fuel consumption, refueling/recharging time, emissions, vehicle price, and well-to-wheel efficiency. Furthermore, the analysis examines the recent sales trends and market performance, thereby offering insights into the advantages and obstacles to adopting of HFCVs on a broader scale. In addition, current and future developments in hydrogen refueling stations and electrolysis capacity are examined, as well as strategies to enhance the integration of HFCVs into the global market. Finally, the study presents an overview of the industry's progress and prospects
Evaluation of the 100 most-cited articles published in veterinary journals
Get PDFBackgroundThe most frequently cited studies in a given field are those which are pioneering and have been widely accepted by the academic community. The aim of this study was to analyse the 100 most-cited articles published in veterinary journals bibliometrically. MethodsThe 100 most-cited articles were identified in the Web of Science database. These articles were bibliometrically examined and visualised. The association between average citations per year, years since publication, number of authors, journal impact factor and article length were assessed by Spearman's correlation analysis. Bibliometric analysis and mapping processes were performed using RStudio software. ResultsAmongst the 100 most-cited articles published between 1980 and 2016, the year 2000 had the highest number of publications (n = 8). The total number of citations ranged from 475 to 1638; the median citation number was 608.5. The most-cited paper was published in 2004 by Desjeux. The country with the most publications was the United States, with 48 articles. A total of 145 institutions contributed to the 100 most-cited papers, with the University of California having the most publications with 12 papers. There was a statistically significant negative correlation between the annual average number of citations and the years since publication (r = -0.769, p < 0.001). No significant relationship was found between the average yearly number of citations and other indicators. ConclusionsThe present study provides insight into research in animal health, offering a comprehensive understanding of the trends and contributions of research in this field
Review of Hans-Johann Glock’s what is analytic philosophy?
Get PDFAnalitik Felsefe Nedir? adlı eserinde Hans-Johann Glock, analitik felsefenin ne olduğu sorusuna kapsamlı ve eleştirel bir yaklaşım sunar. Analitik felsefeyi sabit, kesin bir tanıma indirgeme çabalarının yetersiz kaldığını belirten Glock, kavramsal analiz, dilsel yöntem ya da bilimle yakınlık gibi ölçütlerin hiçbirinin analitik felsefenin tüm örneklerini kapsayamadığını gösterir. Hatta bu geleneği tanımlamak adına kıta felsefesiyle yapılan karşılaştırmalar da istenen sonucu vermez. Glock bu noktada, analitik felsefenin özsel bir tanımdan ziyade tarihsel bir gelenek ve düşünsel etkileşim ağı olduğunu savunur. Analitik felsefeyi Wittgenstein’ın “aile benzerliği” kavramına dayanarak açıklamaya çalışan Glock’ a göre, analitik felsefeyi tanımlayan gerekli ve yeterli koşullar bulunmamakla birlikte, yeterince fazla sayıda paylaşılan özellik, filozofların aynı geleneğe ait olarak görülmesini sağlar. Analitik felsefenin tarihsel gelişimini, coğrafi kökenlerini, yöntemlerini ve etikpolitik yönelimlerini kapsamlı bir şekilde analiz etmeye olanak tanıyan eser, analitik felsefeye ilgi duyan herkes için temel bir kaynak niteliği taşır.In his work What is Analytic Philosophy? Hans-Johann Glock offers a comprehensive and critical approach to the question of what analytic philosophy is. Glock argues that attempts to reduce analytic philosophy to a fixed and definitive definition fall short, demonstrating that criteria such as conceptual analysis, linguistic method, or affinity with science fail to encompass all instances of analytic philosophy. Even comparisons made with continental philosophy in order todefine this tradition do not yield satisfactory results. At this point, Glock maintains that analytic philosophy should be understood not through an essentialist definition but rather as a historical tradition and a network of intellectual interactions. Drawing on Wittgenstein’s notion of “family resemblance,” Glock contends that although there are no necessary and sufficient conditions that define analytic philosophy, a sufficiently large number of shared features enable philosophers to be seen as part of the same tradition. Offering an extensive analysis of the historical development, geographical origins, methodologies, and ethical-political orientations of analytic philosophy, this work serves as a fundamental resource for anyone interested in the fiel
Mullā Shaykh al-Kurdī and his Sharḥ al-Ḥawrāʾ wa-l-Zawrā -critical edition and analysis-
Get PDF17. yüzyıl Osmanlı âlimlerinden Molla Şeyh el-Kürdî, Devvânî’nin mebde (başlangıç) ve meâd (âkıbet) konularına ilişkin görüşlerini yansıtan ez-Zevrâ’ ve el-Havrâ’ adlı eserleri üzerine bir şerh kaleme almıştır. Kürdî bu şerhinde, özellikle başlangıç seviyesindeki öğrencilerin anlayış düzeyine uygun biçimde, Devvânî ve onun eserlerinin bir başka şârihi olan Kemâleddin el-Lârî’nin açıklamalarını tasvir, tahlil ve kritiklere tâbi tutmaktadır. Ayrıca eserde, vahdet-i vücûd (varlığın birliği) ilkesini merkeze alan tartışma ve açıklamalara da yer verilmektedir. Bu tezde, Kürdî’nin özelde ez-Zevrâ’ ve el-Havrâ’ şerhleri, bu bağlamda da İslâm ilim geleneği içerisindeki yeri, şerhinde kullandığı yöntem ve metotlar, Devvânî ve Lârî’ye karşı takındığı entelektüel tutum ile Lârî’nin kaleme aldığı şerhle arasındaki ilişki araştırılarak bu sorulara cevap bulunması amaçlanmaktadır. Çalışmada öncelikle kaynaklarda hakkında yeterli bilgi bulunmayan el-Kürdî’nin hayatı ve eserleri tespit edilerek tanıtmaya çalışılmıştır. Ardından, onun kaleme almış olduğu şerh ve bu şerh çerçevesinde yer alan metinlerle ilgili veriler sunulmaktadır. Araştırmanın önemli bir bölümünü, henüz yazma halinde bulunan Şerhu’l-Havrâ’ ve’z-Zevrâ’ adlı eserin edisyon kritiği oluşturmaktadır. Ayrıca risâlenin muhtevası betimlenip tahlil edilerek çalışmanın başında yöneltilecek sorulara cevaplar aranmaktadır. Molla Şeyh el-Kürdî, gelenek içerisinde özgün görüşler ortaya koymaktan ziyade, mevcut doktrinleri açıklayıcı yaklaşımı, kullandığı yöntem ve tekniklerle dikkat çekmektedir. Ayrıca gelenekteki benzer şerh örneklerine kıyasla dil tefsirlerine daha fazla yer vermesi ve bu alanda eleştirel yorumlarda bulunması bakımından da ayırt edici bir nitelik arz etmektedir. Bununla birlikte, eserde varlığın birliğini benimsediğine dair açıklamaları, tenkitleri ve itirazları, onun vahdet-i vücûd anlayışını sahiplendiğini açıkça ortaya koymaktadır. Bu doğrultuda, kelâmcıları ve filozofları eleştirmekten de geri durmadığı görülmektedir.Mullā Shaykh al-Kurdī, a 17th -century Ottoman scholar, authored a commentary on the works titled al-Zawrāʾ and al-Ḥawrāʾ, which reflects al-Dawwānī’s views on the concepts of mabdaʾ (origins) and maʿād (ultimate return). In this commentary, al-Kurdī analyzes, describes, and critically evaluates the explanations of al-Dawwānī and al-Lārī, particularly in a manner suited to the intellectual level of beginner students. Moreover, the work includes discussions and elucidations centered around the principle of waḥdat al-wujūd (the unity of being). This thesis aims to explore al-Kurdī’s position within the Islamic intellectual tradition, the methods and approaches he employs in his commentary, his intellectual stance toward al-Dawwānī and al-Lārī, as well as the relationship between his commentary and that of al-Lārī. The methodological approach of this study begins by identifying and introducing the life and works of al-Kurdī, about whom limited biographical information is available in the sources. Subsequently, the study presents data concerning his commentary and the texts it engages with. A significant portion of the research is devoted to the critical edition of Sharḥ al-Ḥawrāʾ wa-l-Zawrāʾ, which remains in manuscript form. Following this, the content of the treatise is described and analyzed in order to address the research questions posed at the outset. Rather than offering original doctrinal positions, Mullā Shaykh al-Kurdī draws attention with his explanatory approach to established doctrines, as well as with the methodological and technical strategies he employs. Additionally, his work distinguishes itself from similar examples in the tradition by placing greater emphasis on linguistic analyses and by offering critical commentary in this area. Furthermore, his statements, critiques, and objections in support of the unity of being indicate his clear adoption of the waḥdat alwujūd doctrine. In this context, it is evident that he does not hesitate to critique both theologians and philosophers
Mathematical modeling of crop water production functions for potato
Get PDFCrop water production functions (CWPFs), which describe the relationship between yield and water use, are of great importance in determining the economic value of irrigation, identifying different irrigation strategies, and determining optimum irrigation levels. The main objective of this study was to evaluate the performance of Stewart, Jensen, Minhas, Blank, and Rao functions (CWPF) in predicting tuber yield in potato. Field studies were carried out in 2019 and 2020 in Bursa Yeni & scedil;ehir Vocational School Production Area. Water stress sensitivity indices of crop water production functions were determined using evapotranspiration and yield values in the first year. Tuber yield values simulated with crop water production functions were compared with tuber yield values measured in the field in 2020. Sensitivity indices of potato to water at four different growth stages were determined using five different plant water productivity models. Considering the sensitivity indices of potato to water in four different growth periods, it was determined that the yield formation period (Y) was the most sensitive to water. When the water stress sensitivity indices calculated for four different growth stages of potato were compared, the model of Minhas was recommended
Efficacy of subsequent therapy in patients with hormone-positive advanced breast cancer with disease progression after cdk4/6 ınhibitor therapy: Multicenter real-life data
Get PDFObjectives: The aim of this study was to evaluate the effect of different systemic therapies after CDK4/6 inhibitor therapy on survival outcomes in HR+/HER2− metastatic breast cancer (MBC) patients. Methods: In this retrospective multicenter study, patients who continued chemotherapy (CT), everolimus + endocrine therapy (HT), and other hormonotherapy after treatment with a CDK4/6 inhibitor were compared. Clinicopathological data and survival outcomes were analyzed. Statistical analyses were performed using the SPSS v25 program, survival analyses were performed using the Kaplan–Meier method, and comparisons were made using the log-rank test. Results: A total of 145 patients were included in the study. The groups were similar in terms of baseline characteristics such as age, menopausal status, histology, stage, adjuvant treatment status, and metastatic spread pattern. The rate of recurrent disease was significantly higher in the CT and Everolimus + HT groups compared to the “Other” group (p = 0.027). However, there was no significant difference between the groups in terms of PFS and OS in the general population (p > 0.05). In subgroup analyses, OS was significantly longer in the everolimus + HT group compared to the CT group in those with recurrence duration ≥ 1 year and stable disease course > 6 months during CDK4/6 inhibitor treatment (p = 0.010 and p = 0.039). Conclusions: Although there was no significant difference in overall survival regarding the choice of treatment after a CDK4/6 inhibitor, everolimus + endocrine therapy was observed to have a positive effect on survival in some subgroups. This finding supports individualized treatment