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Predictors of Pouch Failure and Quality of Life Following Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: a Retrospective Multicenter Study
No full textBackground: This study aimed to investigate the causes of failure after the ileal pouch-anal anastomosis (IPAA) procedure for ulcerative colitis (UC) and to determine the independent risk factors affecting their quality of life. Methods: This multi-center cohort study included all UC patients who underwent IPAA at nine referral centers in Türkiye from 2010 to 2018. Centers were categorized as high-volume (≥10 cases/year) or low-volume (10 cases/year). Outcomes assessed included postoperative complications, pouch failure, and QoL using the Cleveland Global Quality of Life (CGQL) and modified Oresland Score. Logistic and linear regression analyses were used to identify risk factors for pouch failure and QoL determinants, respectively. Results: Of 296 patients included, pouches were constructed in 172 (58.1%) as a two-staged and in the remaining patients as a three-staged procedure. The high-volume center had higher rates of biologic (45.1% versus 16%) and steroid use (63.9% versus 22.1%). The overall pouch failure rate was 4.7% at the end of follow-up of 66.1 months. Independent risk factors for pouch failure included pelvic sepsis (OR = 47.47, P = 0.002), biologic use (OR = 13.45, P = 0.033), chronic pouchitis (OR = 14.31, P = 0.013), postoperative blood transfusion (OR = 7.04, P = 0.048), and low annual case volume (OR = 30.86, P = 0.047). CGQL and Oresland scores averaged 0.77 ± 0.1 and 6.3 ± 1.1, respectively. Factors negatively impacting QoL included two-staged procedures, small bowel obstruction, venous thromboembolism, chronic pouchitis, increased frequency of bowel movements, and low annual case volume. Conclusions: IPAA surgery in UC patients in Türkiye demonstrates acceptable rates of complications and pouch failure, with high patient satisfaction in terms of QoL and functional outcomes. Optimizing long-term results requires enhanced surgical expertise and coordinated multidisciplinary management strategies. © 2024 Royal Australasian College of Surgeons
Performance of Water Systems During the February 6th Kahramanmaras Earthquakes
No full textDAL, OGUZ/0000-0003-2173-5623February 6th, 2023 Mw7.7 and Mw7.6 Kahramanmaras earthquakes caused severe damage to lifeline systems across 13 provinces in Turkiye and regions of Northern Syria. Impacts to water and wastewater infrastructure were significant, requiring the mobilization of support from across the region, and around the world to provide life-sustaining service to the approximately 14 million impacted people. This study documents water infrastructure performance during the event and efforts required to repair damage during the days and months that followed. With a particular focus on water transmission and distribution pipelines, details acquired during multiple field reconnaissance visits and meetings with officials are provided for the most heavily impacted water utilities. Both general recovery efforts and specific examples of earthquake-induced pipeline damage are incorporated to draw conclusions relative to emergency preparedness, resilient network design, and communication across agencies as well as with the public.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Parts of the reconnaissance efforts were supported by Gebze Technical University, TUBITAK-1002C, and the Earthquake Engineering Research Institute (EERI).Gebze Technical University [TUBITAK-1002C]; Earthquake Engineering Research Institute (EERI
Examining the Role of System Acceptance and Community Feeling in Predicting Nursing Students' Online Learning Satisfaction
No full textCunkus Koktas, Nesrin/0000-0003-1813-1511Online learning has transitioned from being optional to a mandatory experience in nursing education. Consequently, it is crucial to understand nursing students' satisfaction and the factors influencing it to create and implement a successful online learning environment. This study aimed to examine the roles of system acceptance and community feeling in predicting nursing students' online learning satisfaction. The sample of the relational and cross-sectional study consisted of 451 nursing students studying online in the two universities in Western Turkey. Data were collected using the Personal Information Form, Online Learning Systems Acceptance, Community Feeling Scale, and Satisfaction Scale. A positive correlation was found between the perceived ease and benefit variables and satisfaction levels of nursing students in the study within the scope of online learning systems acceptance. A positive correlation was found between the actional and affective components of community feeling and satisfaction levels of nursing students in the study. Besides, the affective component was found to be the most significant factor in explaining satisfaction with online learning. The learning environment can be improved by increasing the diversity and interaction of nursing students with methods or instruments such as online collaborative learning approaches and online community building
Kesirli mertebeden kısmi türevli denklemlerin çözümü için bir hibrit yöntem ve uygulamaları
No full textBu tezde, Caputo-Fabrizio türevleri ve Laplace dönüşümleri kullanılarak
kesirli diferansiyel denklemlerin çözümü için hibrit ve ileri düzey bir yöntem
sunulmuştur. Çalışma dört ana bölümde düzenlenmiştir.
Birinci bölümde, temel kavramlar ve konunun daha iyi anlaşılmasını
sağlayacak uygulamalı bilgiler sunulmuştur. İkinci bölümde, Riemann-Liouville,
Caputo ve Caputo-Fabrizio gibi kesirli türevlerin tanımları ve özellikleri
incelenmiştir. Üçüncü bölümde, önerilen yöntem tanıtılmış ve bu yöntem, Newell-
Whitehead-Segel denklemi, Jeofiziksel Korteweg-de Vries (gKdV) denklemi gibi
temel denklemler üzerinde uygulanmıştır.
Önerilen yöntem, literatürdeki mevcut çözümlerle karşılaştırılarak
doğruluğu ve etkinliği kanıtlanmış kesin ve verimli çözümler sunmaktadır. Bu
çalışma, mühendislik, fizik ve uygulamalı bilimlerdeki karmaşık sistemlerin
çözümü için güvenilir araçlar sunarak kesirli analiz alanına önemli bir katkı
sağlamaktadır.This thesis develops hybrid and advanced methods for solving fractional
differential equations using Caputo-Fabrizio derivatives and transforms. The study
is organized into four main sections.
The first section introduces fundamental concepts and practical applications
to enhance understanding. The second section examines the definitions and
properties of fractional derivatives, including Riemann-Liouville, Caputo, and
Caputo-Fabrizio. In the third section, the proposed method is introduced and
applied to key equations such as the Newell-Whitehead-Segel equation and the
Geophysical Korteweg-de Vries (gKdV) equation.
In the fourth section, the proposed methods offer accurate and efficient
solutions, validated through comparisons with existing solutions and exact results
in the literature. This research significantly contributes to fractional calculus by
providing reliable tools for addressing complex systems in engineering, physics,
and applied sciences
Comparison of Vibration Values of Rotating Discs With Variable Parameters Obtained by Finite Element Analysis Modeling With Different Machine Learning Algorithms
No full textMuftu, Said/0000-0001-5621-7805; Calliglu, Hasan/0000-0002-4598-7975Purpose - Rotating functionally graded (FG) disks of variable thickness generates vibration. This study aims to analyze the vibration generated by the rotating disks using a finite element program and compare the results obtained with the regression methods. Design/methodology/approach - Transverse vibration values of rotating FG disks with variable thickness were modeled using different regression methods. The accuracies of the obtained models are compared. In the context of comparing regression methods, multiple linear regression (MLR), extreme learning machine (ELM), artificial neural networks (ANNs) and radial basis function (RBF) were used in this study. The error graph between the observed value and the predicted value of each regression method was obtained. The error values of the regression methods used with scientific error measures were calculated. Findings - The analysis of the transverse vibration of rotating FG disks with the finite element program is consistent with the studies in the literature. When the variables and vibration value determined on the disk are modeled with ELM, MLR, ANN and RBF regression methods, it is concluded that the most accurate model order is RBF, ANN, MLR and ELM. Originality/value - There are studies on the vibration value of rotating discs in the literature, but there are very few studies on modeling. This study shows that ELM, MLR, ANN and RBF, which are machine learning methods, can be used in modeling the vibration value of rotating discs
Evaluation Of Knowledge And Attitudes Of Female University Students About Ovarian Reserve Awareness And Technologies For Ovarian Reserve: A Cross-sectional Study;
No full textPurpose: The aim of this study was to evaluate the knowledge and attitudes of female university students about ovarian reserve awareness and technologies for ovarian reserve. Materials and methods: This study was designed as a descriptive and cross-sectional study and was conducted on 660 female university students. The data were collected by using a questionnaire form based on the literature on ovarian reserve and related technologies. The mean, standard deviation and percentage distributions of the data obtained through the WEB page and face-to-face interview technique were analysed in the SPSS programme. Results: 86.2% of the students wanted to have children in the future and 75.8% planned to have children between the ages of 26-30. 56.7% of the students were aware of the availability of tests related to ovarian reserve and 86.6% of them demanded the development of new tests. In case of low ovarian reserve, 65.6% of the students stated that they could have children earlier, 68% could freeze their eggs, 51.2% could freeze their embryos, 73.8% could adopt a child and 84.7% could continue their work/education. Conclusion: It is remarkable that the majority of the students did not make any attempt for ovarian reserve evaluation although they wanted to have a child. Among the reasons for this situation, besides the fact that the students are still receiving education, they have false beliefs that their ovarian reserves will be sufficient at the age when they want to have children, that a healthy lifestyle and activity protect the ovarian reserve, and that they can have children with assisted reproductive techniques even if their ovarian reserves are low. It is important to evaluate the ovarian reserves of young women at an early stage in order for them to make a more conscious career and family planning. © 2025, Pamukkale University. All rights reserved
A New Approach To Efficiency Measurement: Hybrid Jaya Algorithm and Data Envelopment Analysis
No full textKoyuncuoglu, Mehmet Ulas/0000-0002-5437-1865; Yesilyurt, Filiz/0000-0003-1629-4747; Yesilyurt, Muhammet Ensar/0000-0001-5610-3146Efficiency measurement using linear programming is a crucial decision-making problem in operational research. Assessing efficiency scores via Stochastic Frontier Analysis (SFA), a parametric method, becomes challenging when decision-making units (DMUs) have multiple outputs, limiting the information's comprehensiveness. To address this issue, we propose an innovative alternative method that estimates SFA for DMUs with multiple outputs by defining multiple outputs as single outputs that yield the same efficiency. Combining DEA with heuristic methods like the JAYA algorithm offers a novel approach for converting multiple outputs into a single output when inputs and efficiency scores are provided. The JAYA algorithm used in this study includes two stopping criteria: convergence to a specified correlation value and reaching the maximum number of iterations. The proposed method successfully calculates the efficiency of DMUs for datasets of 20, 50, 97, and 100 units with correlation values of 95% and 99%. The JAYA algorithm computed 20, 50, 97, and 100 DMU samples in approximately 0.04, 0.45, 3.96, and 3.22 h, respectively (target correlation values of 95%). This method facilitates faster and more accurate efficiency measurements and enhances the ability to handle datasets with multiple outputs, providing a more robust and comprehensive analysis in operational research
Effects of Spinel Oxide Combustion Catalysts on the Combustion Behavior and Secondary Atomization Mechanism of Gasoline Droplets
No full textThe catalytic activity of Mg-based spinel oxide nanoparticles (NPs) on the combustion behavior of gasoline and their effects on the atomization behavior were determined by droplet scale combustion experiments. MgFe2O4, MgCo2O4 and MgMnO3 spinel oxide NPs were produced by the sol-gel technique and doped into gasoline. The particles with the highest surface oxygen were MgCo2O4 and MgFe2O4 NPs, while the NPs with the largest surface area were MgCo2O4 NPs (517.8433 m2/g). The size of the flame envelope tends to shrink as the oxygen concentration of the particles rises, but an increase in their surface area tends to shorten ignition delay periods. MgFe2O4 NPs increased the flame temperature by 163°C compared to the pure gasoline. While MgFe2O4 and MgMnO3 NPs increased the extinction time of gasoline, MgCo2O4 NPs decreased the severe time by about 75% with the violent micro-explosions they created. In this study, we focused on the production of spinel oxide agents customized for combustion with improved catalytic activity, high flammability, and different component designs, and the results showed that these particles can reduce the soot formation of conventional hydrocarbons. © 2023 Taylor ; Francis Group, LLC.Tarsus Universit
Simulation model for tooth root crack growth in spur gears based on geometric design properties
No full textYıldız, Ahmet Can/0000-0001-6631-414X; Şekercioğlu, Tezcan/0000-0002-9359-8843Tooth root fracture is one of the common types of failure in spur gears. In this study, a simulation procedure has been proposed to evaluate tooth root fracture in spur gears. The study estimates the total fatigue life of spur gears modeled from AISI 4140 hardened steel, including crack initiation and propagation. The strain-life approach was used for fatigue analysis of crack initiation, while the Separating Morphing and Adaptive Remeshing Technology (SMART) was used for crack propagation. The effect of different gear design parameters such as pressure angle, tooth width, profile shift, and crack initiation length on tooth root fracture was evaluated by modeling different geometric variations. Through extensive simulations carried out in Ansys software, it was found that the highest crack propagation occurred in the 25 degrees pressure angle variation. In contrast, the lowest crack propagation was observed in the negative profile shift variation. Increasing the pressure angle and the positive profile shift increases the fatigue life of spur gears. Additionally, increasing the tooth width significantly increases fatigue life. Zahnfu ss bruch ist eine der h ; auml;ufigsten Fehlerarten bei Stirnr ; auml;dern. In dieser Studie wurde ein Simulationsverfahren zur Bewertung des Zahnfu ss bruchs in Stirnr ; auml;dern vorgeschlagen. Die Studie sch ; auml;tzt die gesamte Erm ; uuml;dungslebensdauer von Stirnr ; auml;dern, die aus geh ; auml;rtetem Stahl AISI 4140 modelliert wurden, einschlie ss lich Rissentstehung und -ausbreitung. Der Dehnungs-Lebensdauer-Ansatz wurde f ; uuml;r die Erm ; uuml;dungsanalyse der Risseinleitung verwendet, w ; auml;hrend die Separating Morphing and Adaptive Remeshing Technology (SMART) f ; uuml;r die Rissausbreitung eingesetzt wurde. Die Auswirkung verschiedener Zahnradkonstruktionsparameter wie Eingriffswinkel, Zahnbreite, Profilverschiebung und Risseinleitungsl ; auml;nge auf den Zahnfu ss bruch wurde durch Modellierung verschiedener geometrischer Variationen bewertet. Durch umfangreiche Simulationen in der Ansys-Software wurde festgestellt, dass die h ; ouml;chste Rissausbreitung bei der 25 degrees-Eingriffswinkelvariante auftrat. Im Gegensatz dazu wurde die geringste Rissausbreitung bei der Variante mit negativer Profilverschiebung beobachtet. Eine Vergr ; ouml;ss erung des Eingriffswinkels und der positiven Profilverschiebung erh ; ouml;ht die Erm ; uuml;dungslebensdauer von Stirnr ; auml;dern. Au ss erdem erh ; ouml;ht eine Vergr ; ouml;ss erung der Zahnbreite die Erm ; uuml;dungslebensdauer erheblich.Pamukkale niversitesi [2024FEBE006]; Scientific Research Projects Unit of Pamukkale UniversityThis work was supported by the Scientific Research Projects Unit of Pamukkale University (Project No: 2024FEBE006)
Digital Motherhood in the Postpartum Period: a Descriptive Study
No full textBackground: During the first 6 weeks after birth, women often encounter problems and seek answers to their questions. This period is also crucial in terms of technology use. Aim: The aim of this study was to examine the digital motherhood approach to self-care and infant care in the 6-week postpartum period, and its association with different variables. Methods: This descriptive study recruited 278 women in the postpartum period. Data were collected from the Digital Motherhood Survey. Descriptive statistics and chi-squared analysis were performed. Results: The mean age of the women was 28.9 ± 5.14 years; 50.4% had a high school education or less, and 49.6% had a university education or higher. The types of digital media consulted included institutional sites, blogs, and commercial sites. The three topics most frequently researched by women in the postpartum period using digital media were breastfeeding, infant nutrition, and general infant care. The top three reasons given by participants for preferring digital media were faster access to information, access to information from their own setting, and benefiting from the experiences of others. The following factors were significantly associated with digital media being a participant’s first-choice information source: the woman and her partner having a university education or above, having a male infant, having received information about infant care, and having a postpartum hospital stay duration of 0–2 days. Conclusion: This study defined postpartum digital motherhood. The preference of women for digital media is influenced by their educational status and that of their partners, the sex of the infant, their prior knowledge of infant care, and the early discharge of their infants after birth. Healthcare professionals, especially nurses, must be aware of the digital media used by postpartum women to supervise them and provide guidance. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2025.Pamukkale University Scientific Research Projects Coordinatorship, (2022HZDP014