In vivo performance of antibiotic embedded electrospun PCL membranes for prevention of abdominal adhesions

The aim of this study was to prepare nonwoven materials from poly(-caprolactone) (PCL) and their antibiotic containing forms by electrospinning, so as to prevent postsurgery induced abdominal adhesions in rats. -Caprolactone was first polymerized by ring-opening polymerization, and then it was processed into matrices composed of nanofibers by electrospinning. A model antibiotic (Biteral®) was embedded within a group of PCL membranes. In the rat model, defects on the abdominal walls in the peritoneum were made to induce adhesion. The plain or antibiotic embedded PCL membranes were implanted on the right side of the abdominal wall. No membrane implantation was made on the left side of the abdominal wall that served as control. Macroscopical and histological evaluations showed that using these barriers reduces the extent, type, and tenacity of adhesion. The antibiotic embedded membranes significantly eliminated postsurgery abdominal adhesions, and also improved healing

In vitro and in vivo degradation of non-woven materials made of poly(e-caprolactone) nanofibers prepared by electrospinning at different conditions

The aim of this study was to prepare non-woven materials from a biodegradable polymer, poly(ε-caprolactone) (PCL) by electrospinning. PCL was synthesized by ring-opening polymerization of ε-caprolactone in bulk using stannous octoate as the catalyst under nitrogen atmosphere. PCL was then processed into non-woven matrices composed of nanofibers by electrospinning of the polymer from its solution using a high voltage power supply. The effects of PCL concentration, composition of the solvent (a mixture of chloroform and DMF with different DMF content), applied voltage and tip–collector distance on fiber diameter and morphology were investigated. The diameter of fibers increased with the increase in the polymer concentration and decrease in the DMF content significantly. Applied voltage and tip–collector distance were found critical to control 'bead' formation. Elongation-at-break, ultimate strength and Young's modulus were obtained from the mechanical tests, which were all increased by increasing fiber diameter. The fiber diameter significantly influenced both in vitro degradation (performed in Ringer solution) and in vivo biodegradation (conducted in rats) rates. In vivo degradation was found to be faster than in vitro. Electrospun membranes were more hydrophobic than PCL solvent-casted ones; therefore, their degradation was a much slower process

Ulaştırma Yatırımlarının Türkiye Ekonomisi Üzerine Makro, Mikro ve Bölgesel Düzeydeki Etkileri: Mekansal hesaplanabilir genel denge modeli kapsamında

thesis (M.A) -- İstanbul Technical University, Institute of Social Sciences, 2018Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Sosyal Bilimler Enstitüsü, 2018This thesis develops a framework for economic analysis of highway projects in Turkey, estimating the economic effects of these projects on regional welfare and economic growth. The framework integrates a transport model with a multiregional Computable General Equilibrium (CGE) model. The CGE model is developed for eight sectors of eight macro regions plus three biggest cities, namely Istanbul Area, Ankara Area and Izmir Area. Three counterfactual experiments are developed based on decreases in transportation margins due to a 'distance shortening'. All simulation results show that highway investment program improves welfare for all regions but in different levels according to scenarios.Bu tez Türkiye'deki farklı otoyol projelerinin bölgesel refah ve büyüme üzerine etkilerinin bölgesel düzeydeki tahmini için gerekli ekonomik analiz çerçevesi oluşturmaktadır. Bu çerçeve kapsamında çok bölgeli Hesaplanabilir Genel Denge (HGD) modeli ile ulaştırma modeli entegre edilmektedir. Tez kapsamında oluşturulan HGD modeli 3 büyük kentimiz ve 8 toplulaştırılmış bölge olmak üzere toplamda 11 bölge için 8 farklı sektör için geliştirilmiştir. Ulaşımdaki mesafeler vasıtasıyla ulaştırma marjlarındaki düşüşü 3 farklı senaryo kapsamında ele alınmıştır. Tüm senaryo çıktıları göstermektedir ki otoyol yatırımları, senaryoya göre farklı bölgelerde farklı seviyede olmakla beraber, tüm bölgelerde refahı arttırmaktadır.M.AYüksek Lisan

The influence of an anterior cruciate ligament injury on behavioral and cortical dynamics associated with superior pass accuracy in football

Fußball gehört zu den populärsten Sportarten der Welt und wird erheblich von Verletzungen des vorderen Kreuzbands (VKB) beeinflusst. Bestehende Evidenzen deuten auf Leistungseinbußen nach ACL-Verletzungen begleitet von Veränderungen des zentralen Nervensystems hin, jedoch fehlen fußballspezifische Erkenntnisse in den Studien. Die vorliegende Arbeit untersucht die Auswirkungen von VKB-Verletzungen auf die Passgenauigkeit, eine Schlüsselkompetenz im Fußball, aus neurowissenschaftlicher Sicht. Eine initiale Literaturrecherche fasste neurophysiologische und neurokognitive Veränderungen nach Verletzungen zusammen und wies auf visuell-räumliche und aufmerksamkeitsbezogene Defizite sowie einen Mangel an sportartspezifischen Aufgaben in experimentellen Paradigmen hin. In Studie I wurden mittels EEG die reliablen kortikalen Korrelate einer Passaufgabe identifiziert, wobei die Aktivität in posterioren und frontalen Regionen visuell-räumliche und aufmerksamkeitsbezogene Prozesse hervorhob. Studie II untersuchte, wie Fußball-Expertise diese Prozesse beeinflusst, und legte nahe, dass erfahrene Spieler durch spezifische visuelle und Aufmerksamkeitsstrategien optimierte Genauigkeit erreichen. Studie III verglich Bewegungsstrategien und kortikale Aktivität zwischen gesunden und verletzten Spielern und zeigte sensorische Veränderungen und deren Kompensation durch erhöhte Aufmerksamkeit, was die visuell-räumliche Verarbeitung beeinträchtigte und die Integration aufgabenbezogener Informationen reduzierte. Diese Arbeit verdeutlich, wie VKB-Verletzungen kortikale Prozesse beim Passspiel beeinflussen können, und unterstreicht das Potenzial für weiterführende Forschung.Football is one of the most played sports worldwide, significantly impacted by anterior cruciate ligament (ACL) injuries. Existing evidence indicates performance declines after ACL injuries accompanied by changes in the central nervous system, but lacks football-specific insights. The current dissertation investigates the effects of an ACL injury on pass accuracy, a key skill in football, from a neuroscientific perspective. An initial literature review identified neurophysiological and neurocognitive changes post-injury, revealing visuospatial and attentional deficits in athletes and a lack of sport-specific tasks used in experimental paradigms. Study I developed a passing task compatible with mobile EEG and identified its reliable cortical correlates, with posterior and frontal activity highlighting visuospatial and attentional processes. Study II examined how these dynamics are influenced by expertise in football and found that experienced players use distinct visual and attentional strategies to achieve improved accuracy. Study III compared kicking behavior and associated cortical activity between healthy and injured players, revealing sensorimotor changes and their compensation through increased attention at the cost of visuospatial processing, which ultimately caused reduced integration of task-related information into networks in injured players. Collectively, this cumulative work illustrates how ACL injuries affect cortical processes in skilled passing and underscores the potential for prospective research in sports injuries.by Dağhan Pişkin ; Principle supervisor: Prof. Dr. rer. med. Jochen BaumeisterTag der Verteidigung: 11.12.2024Kumulative Dissertation Universität Paderborn, Dissertation, 202

Economic evaluation of transportation projects based on different financing methods: at the framework of financial computable general equilibrium model

Purpose- The purpose of this study is to develop a first fully functional Turkish Financial Computable General Equilibrium (FCGE) model that analyzes the economic impacts of infrastructure investment projects under different financing options. We examine three alterantive financing methods, i.e., public financing with tax revenues and government bonds, public financing with region specific tax policy and private financing. Methodology- The study employs Financial Computable General Equilibrium (FCGE) model. The FCGE model integrates the real economy with the financial one, and traces the flows of financial and real resources among economic agents at the same time. Computable General Equilibrium (CGE) models typically are comparative static equilibrium models of interregional trade and location based in microeconomics, using utility and production functions with substitution between inputs. The transport system enters the spatial economy through the costs of transport services. Transport sub models are applied to feed CGE models with cost changes in the transport sector as a result of policy measures. Our model is composed of a multi-regional financial CGE model and a transport network model. Turkish Multi Regional Computable General Equilibrium model constitutes of 11 regions. The model includes ten producers, one regional household, one national (or central) government and the rest of the world. Findings- The model is designed to analyze the economic effects of fiscal policies such as the transportation investment expenditures and alternative financing approaches on economic growth and welfare. It is possible to estimate growth and distributional effects of each project based on the financing method once the information on the investment expenditures, the construction location and the changes in the accessibility generated by the project are injected into the FCGE model. As a first attempt, we builded a Financial Social Accounting Matrix (SAM) for Turkey that FCGE models need, containing the details of financial institutions and transaction of agents’ assets and liabilities. The model specifies the behaviours of ten different sectors, one household, a central government, and the rest of the world. The model is designed to analyze the impacts of highway development with different financing strategies. We examine three alterantive financing methods: it can (a) public financing with tax revenues and government bonds, (b) public financing with region specific tax policy or (c) private financing. Conclusion- The main contribution of this research is to develop a first fully functional FCGE model to analyze the economic impacts of the infrastructure investment projects and their financing options on growth and welfare in Turkish economy. We develop a first fully functional Turkish Financial Computable General Equilibrium (FCGE) model that analyzes the economic impacts of infrastructure investment projects under different financing options. There are a number of ways to finance highway infrastructure investment: fuel taxes, user fees, trust funds etc. This Financial CGE model is expected to assess the consistency of highway investment programs under different financing options, so the government can make a decision on an approval for the project based according to their benefits and costs on national level

Investigation of Middle School Students’ Solution Strategies in Solving Proportional and Non-proportional Problems

The purpose of this study was to investigate middle school students’ solution strategies in solving different types of proportional (i.e., missing value, numerical comparison and qualitative reasoning problems) and non-proportional problems and to compare if differences existed between sixth and eighth grades students’ solution strategies. Data were collected from 101 sixth grade (n=44) and eighth grade (n=57) students from three different public middle schools. The students were asked to solve ten open-ended items that included seven proportional problems and three non-proportional problems. Descriptive data analysis methods were used to analyze data. The results revealed that the students’ solution strategies differed based on problem type and grade level. The eighth grade students used cross-multiplication as a leading strategy whereas the sixth grade students used factor of change strategy. Moreover, the results showed that students commonly used incorrect proportional strategies to solve non-proportional problems