The impact of structural funds on local government in the EU: cases of the UK (England) and Germany

The introduction of Structural Funds and the control which the European Commission holds over them have created pressure on cities, whereby they have paved the way for a transition from local government to a networked form of local governance. Accordingly, this thesis examines the impact of European Structural Funds on patterns of governance at the local level and assesses whether they imply a move towards the harmonization of urban governance across the European Union (EU), considering four basic themes: horizontal governance; vertical governance; participation of the community, and policy learning through trans-national networks. Finally, after comparing and contrasting the impacts of Structural Funds on the deliberatly chosen case studies, namely the UK (England) —a highly centralized unitary state with weak local authorities— and Germany —a federal state with both constitutionally and politically powerful local authorities—, the study concludes that although the arrival of the EU funding is a primary shock to the existing structures, they did not induce a harmonization among the member states due to their specific circumstances

A novel approach for cardiotocography paper digitization and classification for abnormality detection

Cardiotocography (CTG) is a clinical procedure that is used to track and gauge the severity of fetal distress. Although CTG is the most often used equipment to monitor and assess the health of the fetus, the high rate of false positive results due to visual interpretation significantly contributes to needless surgical delivery or delayed intervention. In this study, a novel approach is introduced where both printing CTG paper is digitized and a machine learning approach is employed to detect the abnormality in the digitized CTG signal. Image processing-based preprocessing steps are employed to make the printing of CTG paper more convenient to extract the CTG signal. Various signal-processing techniques are used to calibrate the extracted CTG signal. Then, Empirical Mode Decomposition (EMD) is used to decompose the CTG signal into its frequency components and instantaneous frequency and spectral entropy features are extracted. After feature normalization and feature selection with ReliefF algorithm, support vector machines (SVM) is used for the classification of the normal and abnormal classes. A novel dataset is used in the experimental works and various performance evaluation metrics are used for the evaluation of the achievement of the proposed method. 10-fold cross-validation-based experiments show that the proposed method is quite efficient in abnormality detection in printing CTG papers where an average accuracy score of around 90.0% is produced

The distribution of hepatitis c virus genotypes in patients with chronic hepatitis c ınfection

Amaç: Hepatit C virüsü (HCV), kronik hepatit, siroz ve hepatosellüler karsinoma yol açarak dünya çapında önemli bir sağlık sorunu olmaktadır. Dizi analizi çalışmaları ile HCV’nin 7 genotipi ve 100’den fazla alt tipi olduğu ortaya konmuştur. HCV genotip 1’in genotip 2 ve 3’e göre daha ciddi hastalık yaptığı ve tedaviye kalıcı yanıtın daha az olduğu bilinmektedir. Bu çalışmada, kronik hepatit C hastalarında genotip dağılımının belirlenmesi amaçlanmıştır. Gereç ve Yöntemler: Çalışmaya, Ağustos 2007-Aralık 2010 tarihleri arasında Adnan Menderes Üniversitesi Tıp Fakültesi, Tıbbi Mikrobiyoloji Anabilim Dalı Laboratuvarında, anti-HCV ve HCV-RNA pozitif olarak saptanan toplam 50 kronik hepatit C’li hasta dahil edildi. Hasta örneklerinde anti-HCV ticari mikropartikül Enzyme-Linked immunosorbent assay test kiti ile (Murex anti-HCV, UK), otomatize sistemde (Grifols Triturus, İspanya) araştırıldı. HCV-RNA düzeyleri, real-time polimeraz zincir reaksiyonu yöntemi ile iki ayrı sistem (Rotor-Gene 6000, Corbett Research, Amerika ve Cobas Tagman, Roche Diagnostic, Amerika) kullanılarak çalışıldı. HCV genotip tayini, virüs genomundaki 5’UTR bölgesinin amplifikasyon ürünlerinin ters hibridizasyonu temeline dayanan ticari HCV-TS test kiti (AB analytica, İtalya) ile yapıldı. Bulgular: Çalışmaya alınan toplam 50 hastanın 27’si (%54) kadın, 23’ü (%46) erkek olup yaş ortalaması 59,92±13,02’dir. Hastalarda HCV genotipleri, 36’sında (%72) genotip 1b, dokuzunda (%18) genotip 1a, birinde (%2) genotip 2b, birinde (%2) genotip 3 ve üç (%6) hastada ise genotip 1a ve 1b olarak belirlenmiştir. HCV genotipleri arasında HCV-RNA düzeyleri ve anti-HCV indeks değerleri bakımından istatistiksel olarak anlamlı bir fark saptanmamıştır (p>0,05). Sonuç: Hastanemizde izlenen kronik HCV olgularında genotip 1b, ülkemizdeki önceki veriler ile uyumlu olarak en yüksek oranda saptanmıştır.Objective: Hepatitis C virus (HCV) infection represents a major public health problem worldwide. HCV can cause chronic hepatitis infection which may ultimately result in cirrhosis and hepatocellular carcinoma. Seven major genotypes and more than 100 subtypes of HCV are shown by sequence analysis. Genotype 1 is associated with more severity of liver disease than genotypes 2 and 3 and sustained response to treatment is known to be less. In this study, we aimed to determine the HCV genotype distribution in chronic hepatitis C patients. Materials and Methods: A total of 50 patients with chronic HCV infection who attended the Microbiology Laboratory at Adnan Menderes University Hospital between August 2007 and December 2010 found to be positive for anti-HCV and HCV-RNA were included in the study. Anti-HCV testing was performed using microparticle Enzyme-Linked immunosorbent assay test kit (Murex Anti-HCV version 4, UK) with autoanalyser (Grifols Triturus, Spain). The quantification of serum HCV-RNA was carried out by a realtime polymerase chain reaction method with two different systems (Cobas TaqMan HCV, Roche Diagnostics, Germany and Rotor- Gene 6000,Corbett Research, USA). HCV genotype analysis was performed by using a kit (HCV-TS; AB Analitica, Italy ) based on the reverse hybridization of 5’-untranslated region and amplified products with genotype-specific probes. Results: The mean age of the 50 chronic hepatitis C patients [27 (54%) female, and 23 (46%) male] was 57.1±14.3 years. Genotype 1b was found in 36 (72%) subjects, genotype 1a in nine (18%), genotype 2b in one (2%), genotype 3 in one (2%), and genotype 1a/1b was found in three (6%) patients. No statistically significant difference was detected in HCV-RNA quantities and anti-HCV index between HCV genotypes (p>0.05). Conclusion: Compatible with the previous data obtained in Turkey, genotype 1b was found to be the most common HCV genotype in patients with chronic hepatitis C followed in our hospital

Does blood type have an effect on the course of COVID-19?

Introduction Predictive parameters that can affect the course of this infection have been the main topic of research since the beginning of the COVID-19 (Coronavirus disease 2019) pandemic. Since the discovery of blood groups, the effect of these on infectious diseases has always been of interest. Objectives To analyze the effect of ABO blood group on mortality, hospitalization duration and hematological and cytokine storm parameters in patients with COVID-19. Patients and methods: This retrospective study was conducted on 140 patients diagnosed with COVID-19. Demographic characteristics, laboratory parameters including ABO blood group, complete blood count (CBC) parameters, biochemical tests, cytokine storm parameters, duration of hospitalization, and final status (discharge or death) were recorded. Results: The 140 patients included in the analysis comprised 72 (51.4%) males and 68 (48.6%) females with a mean age of 66.3±14.0 years. . Age and gender, hospitalization duration and mortality rates were similar in all blood group types. Only D-dimer levels were found to be higher in blood group A compared with other blood groups. Conclusion: Although no difference in mortality was determined between groups, the D-dimer level was statistically significantly higher in COVID-19 patients with A blood group. Larger studies are needed to reflect D-dimer levels on the clinical course of infection, and thus on daily practice

Single Centre Experience: Bening and Malign Hematological Patients with COVID-19

Introduction Coronavirus disease 2019 (COVID-19) were declared as pandemic by World Health Organization. With this study, we aimed to define our patients who were followed up with malign or benign hematological diagnoses and diagnosed with COVID-19; determine the distribution of this infection in patient groups and contribute to the literature by creating descriptive statistics with its clinical and demographic features. Patients and methods: It is planned to retrospectively examine patients with a history of COVID-19 who were followed up in Hematology Department of Dışkapı Yıldırım Beyazıt Training and Research Hospital with benign and malignant diagnoses. Results: 88 patients who had COVID-19 infection while being followed in our clinic due to hematological diseases were included in the study. 77 patients had been followed by hematologic malignancies and 11 patients had been followed by benign hematological disease.In the group with malignancy, COVID was found most frequently in patients diagnosed with Philadelphia chromosome negative myeloproliferative neoplasms (22%), nonhodgkin lymphoma (19%) and multiple myeloma (16%). ITP (64%) was the most common disease in patients with benign hematological disorder who had COVID history. 52 (67%) of the malignant cases and 8 (73%) of the bening cases were found to be followed up with the disease in remission. The all patient's most common symptoms at COVID-19 diagnosis were fever (77%), cough (70%) and weakness (65%). 45% of the patients were isolated at home, 48% were required hospitalization. 49% of patients had mild; 27% had moderate and 24% had severe COVID-19 infection. Almost all of the patients in the moderate and severe disease group were followed up in patients diagnosed with malignant hematological disease. 16 (18%) patients received mechanical ventilation and 16 (18%) patients was transferred intensive care unit. All of the patients who were intubated and needed intensive care were diagnosed with malignant hematological disease. 17 patients died due to COVID-19 infection. The mortality rate was 22% in patients with diagnosis of malignant hematological diseases, and 19% when all patients (malignant and bening) were included. Conclusion: In conclusion, the COVID-19 pandemic is a problem all over the world. Determining the course of the disease in certain diagnostic groups is important in the management of both the main disease and the COVID-19 infection. Therefore, the contribution of such recording studies to the literature is important and valuable

Kalite iyileştirmede veri madenciliği kullanımı ve geliştirilmesi

TÜBİTAK MAG30.06.2009Bu projede amaç, sanayi kuruluşlarında ürün ve süreçlerin kalitesini iyileştirmeye yönelik veri madenciliği (VM) yaklaşımlarını belirlemek ve daha etkili yaklaşımlar geliştirmektir. Projede imalat sanayi kuruluşlarının ürün ve süreçlerinin kalitesini iyileştirme ile ilgili kalitenin tanımlanması, tahmin edilmesi, sınıflandırılması ve parametrelerinin optimizasyonu problemleri ele alınmıştır. Bu problemlerin çözümü için veri hazırlama ve önişlemenin yanısıra kümeleme, tahmin etme, sınıflandırma, birliktelik analizi ve optimizasyon VM işlevlerinin gerekli olabileceği belirlenmiştir. Bu kapsam dahilinde geniş bir literatür taraması yapılmış ve değişik imalat sektörlerinde etkinlik gösteren altı kuruluş ziyaret edilmiştir. Bunlardan üçünün sağladığı veriler üzerinde uygun VM metotları uygulanmış ve sonuçlar karşılaştırılmıştır. Bu karşılaştırma sonucunda belli VM işlevleri için kalite iyileştirme amaçlarına en uygun VM metotları belirlenmiş ve uygulayıcılara önerilmiştir. Projenin yöntem geliştirme kısmında ise uygulama aşamasında karşılaşılan bazı problemlerin giderilmesi ve mevcut yöntemlerin kullanım kolaylığı ve/veya etkililiğinin artırılması yönünde çalışmalar gerçekleştirilmiştir. Sonuçta, kalite verilerinin yeniden örneklenmesi için bir yöntem; parametrik olmayan alternatif bir regresyon yaklaşımı (CMARS); ikili sınıflandırmada kullanımı kolay olan Mahalanobis Taguchi Sistemi metodunun çok sınıf ve ayrıca parametre optimizasyonu için uyarlamalar; bulanık sınıflandırmada kalite verilerine uygun alternatif yaklaşımlar (bulanık regresyona dayalı modeller) ve parametrik olmayan bulanık tahmin etme ve sınıflandırma fonksiyonları; parametre optimizasyonunda çekicilik fonksiyonlarının optimizasyonu için alternatif yaklaşımlar ve birliktelik kurallarının seçimi için bir yöntem geliştirilmiştir. Bu sonuçların ve metotların kalite iyileştirme alanında uygulayıcıların çalışmalarına yön vermesi ve bunların kullanım kolaylığı ile etkililiğini artırması beklenmektedir.The objective of this project is to identify the data mining (DM) approaches that can effectively improve product and process quality in industrial organizations, and to develop more effective approaches. In the project, quality definition, prediction, classification and parameter optimization problems associated with product and process quality improvement in manufacturing industries are considered. For the solution of these problems, clustering, prediction, classification, association and optimization functions of DM as well as data preparation and preprocessing are determined as relevant. A comprehensive literature survey has been performed and six manufacturing companies operating in different sectors have been visited, within this context. Appropriate DM methods are applied on data sets obtained from three of these companies, and the results are compared. As a result, the most appropriate DM methods are suggested for specific DM functions and quality improvement purposes. In the method development part of the project, studies are performed to overcome some problems encountered during the applications, and to increase ease of use and effectiveness of the VM methods. As a result, a resampling method for quality data; an alternative nonparametric approach (CMARS) for regression; adaptations of an easy to use binary classification method, Mahalanobis Taguchi system, to multiple classes and also to parameter optimization; alternative approaches for fuzzy classification of quality data (models based on fuzzy regression) and nonparametric fuzzy functions; alternative approaches for optimization of desirability functions in parameter optimization; and a method for reduction of association rules are developed. It is expected that these results and approaches guide practitioners in quality improvement area, and incease the ease of use and effectiveness of them

The genetic history of the Southern Arc: a bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra–West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe

Preparation Of Shape Memory Polyurethane Gels Containing Iron

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2015Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2015Poliüretanlar, şekil hafıza özelliğine sahip olmalarından dolayı son yıllarda ilginin giderek arttığı akıllı malzemelerdir. Sahip oldukları mekanik, termal, manyetik ve biyouyumluluk özelliklerinden dolayı stent, implant, ilaç salınımı gibi biyomedikal alanlarda yaygın bir şekilde kullanılmaya başlanmıştır.  Günümüzde, özellikle medikal alanda, polimer ve manyetik özelliğe sahip malzemeler kullanılarak hazırlanan kompozit malzemeler büyük ilgi çekmektedir. Bu kompozitler sayesinde manyetik alan altında da şekil hafıza özelliği gösterebilen polimerik malzemeler geliştirilmektedir. Bu çalışmanın amacı, medikal alanda kullanılmak üzere, manyetik alanda şekil hafıza özelliği gösteren biyouyumlu poliüretan (PU) jeller sentezlemektir. Çalışmada; poliüretan ve manyetit (Fe3O4)’ten oluşan polimerik kompozit malzemeler sentezlenmiştir. Bu kompozitlerin sentezinde, poliol olarak polietilen glikol 300 (PEG300), polietilen glikol 3000 (PEG3000) ve hint yağı (HY), zincir uzatıcı olarak 1,4-bütandiol (BDO), izosiyanat kaynağı olarak hekzametilen diizosiyanat (HDI) kullanılmıştır. HY aynı zamanda sentezde çapraz bağlayıcı görevi de görmektedir. Sentezlerde herhangi bir çözücü veya katalizör kullanılmamıştır. Sentezlenen PU filmlerin ısı etkisi haricinde manyetik alan altında da şekil hafıza özelliği gösterebilmesi için poliüretan filmlerin içerisine mikro boyutta Fe3O4 partikülleri eklenmiştir. Manyetitin, poliüretan içerisindeki miktarı ağırlıkça %0 ile %10 arasında değişmektedir. Böylelikle manyetit yüzdesinin, manyetik alan altında ve değişik sıcaklarda kompozit malzemenin şekil hafıza özelliğine etkisi araştırılmıştır. Çalışmada HY/PEG oranları sabit tutularak sadece film içerisindeki manyetit yüzdelerinin şekil hafıza performansına etkisi araştırılmıştır. Manyetit içeren PU filmlerin şekil hafıza performansları belirlenirken, oldukça basit fiziksel bir test olan bükülme testinden faydalanılmıştır. Bu test ile PU filmlerin, şekil kararlılığı ve şekil hatırlama oranları belirlenmiştir. PU filmlerin sentezinde HY/PEG oranı değiştirilmediğinden sert bölge içeriği tüm filmlerde aynıdır. PU filmlerin biyouyumlu olması sebebiyle olası biyomedikal uygulamalarda kullanabilirliğini araştırmak amacıyla, filmlerin öncelikle 40 oC’de şekil kararlılığı ve şekil hatırlama oranları incelenmiştir.  Ayrıca bükülme testleri 65 oC sıcaklık ve manyetik alan altında uygulanarak sonuçlar birbiri ile kıyaslanmıştır.    Manyetit partikülü içeren PU filmlerin yapısal karakterizasyonu için Fourier dönüşümlü kızılötesi (FT-IR) spektroskopisi, ısıl karakterizasyonu için ise ısıl gravimetrik analiz (TGA), diferansiyel taramalı kalorimetre (DSC) ve viskoelastik özelliklerin belirlenebilmesi için dinamik mekanik analiz (DMA) cihazları kullanılmıştır. Sentezlenen PU filmlerin saf su içerisinde şişme davranışları ve Soxhlet ekstraktörü ile yüzde jel içerikleri belirlenmiştir. PU kompozit filmlerin çapraz bağ yoğunluğu ve iki çapraz bağ arasındaki ortalama molekül ağırlığı, DMA verilerinden yola çıkılarak hesaplanmıştır. Manyetit katkısının poliüretanın hidrofilik özelliğine etkisini belirlemek amacıyla, sentezlenen PU filmlerin yüzey temas açısı ölçümleri yapılmıştır. Poliüretan kompozitlerin şekil hafıza özelliğini etkileyen parametreler; sert bölge içeriği, kristalinite, camsı geçiş sıcaklığı, çapraz bağ yoğunluğu ve film içerisindeki katkı maddesi miktarıdır. Yapılan çalışmada, sert bölge içeriği sabit tutularak manyetit katkısının şekil hafıza özelliğine etkisi araştırılmıştır. PU film içerisinde değişen manyetit yüzdesi, kristalinite, camsı geçiş sıcaklığı ve çapraz bağ yoğunluğu değerlerini etkilemektedir. Bu nedenle şekil hafıza performansı katkı yüzdesi ile farklılık göstermektedir. Çalışmada elde edilen sonuçlara göre; PU film içerisindeki manyetit yüzdesi arttıkça malzeme sertleştiğinden şekil kararlılığı (Rf) katkısız poliüretana göre azalmaktadır. Ancak bu özellik şekil hatırlama (Rr) oranının artmasına neden olmaktadır. Yapılan bu çalışmada, şekil hatırlama basamağı 40 ve 65oC olmak üzere iki farklı sıcaklıkta ve manyetik alan altında uygulanmıştır. Bükülme testinin ilk basamağı olan ısıtma basamağı 40 ve 65 oC’de, ikinci basamağı olan soğutma basamağı ise 4 oC’de uygulanmıştır. Elde edilen sonuçlara göre 65 oC Rf ve Rr değerleri daha yüksektir. Şekil hafıza özelliğinin tekrar kullanabilirliğini araştırmak amacı ile bükülme testi her numune için, aynı örnekte 10 defa tekrarlanmıştır ve şekil hafıza performanslarında önemli bir değişme olmamıştır. Beklendiği şekilde, manyetit yüzdesinin artması ile PU kompozitlerin yoğunlukları da artmıştır. Sentezlenen PU filmlerdeki manyetit katkısı arttıkça, filmlerin su tutma kabiliyeti zorlaşmış ve şişme oranları azalmıştır. Manyetit katkısı poliüretan filmlerin yüzey hidrofilik özelliğinin azalmasına sebep olmuştur. Çalışma sonuçları birlikte değerlendirildiğinde, manyetitin de insan sağlığına herhangi bir zararı olmadığı bilindiğinden, %0-10 manyetit içeren poliüretan filmlerin şekil hafıza özelliğinden faydalanılarak vücut içi uygulamalarda kullanılabilecek biyomedikal malzemeler hazırlanabileceği sonucuna varılmıştır.There are many interesting materials in the world, and every day a new one is produced according to the needs with engineering applications. One of the most important of these materials are able to maintain the original shape against changing physical and chemical stimuli. The types of stimuli include; heat, voltage, pressure, electric current, magnetic field, change of pH, solvent or  moisture level, light and other factors. These type of materials are known as stimuli-responsive materials. Stimuli-responsive materials are used in many areas due to protect their original shape against these stimulus. Stimulus-responsive polymers and composites in recent years, drug release, and in issues such as gene transfer has become a very important materials. Showing heat sensitivity of shape memory polymers are composed of crystalline phase and amorphous phase. Melting point and glass transition temperature, is a key information nematic phase transition from the isotropic phase. Physical and chemical crosslinking is an important factor for ability to return to the original shape. Developed most important shape memory materials are shape memory alloys and shape memory polymers. Shape memory polymers based on polynorborne is manufactured as first generation shape memory polymers in 1984 by Nippon Zeon Company in Japan. Later trans-izopoliprem and styrene-butadiene based shape memory polymers have been developed. Thermoplastic shape memory polyurethane was invented in 1990 by Dr. S. Hayashi. The main advantages of shape memory polymers are; low density and price, easy production of high quality, high tension strength, shape recovery in wide temperature range, high damping ratio in transition region, low-cost recycling, excellent chemical stability, biocompatibility, high biodegradability, suitability to use in the human body and flexibility. Shape memory polymers are important materials that have dual-shape capability. Shape memory effect only relies on the molecular architecture. Therefore, material properties can be adjusted with monomer type or comonomer ratio.  Shape memory polymers, stimuli sensitive switches is equipped with an elastic polymer networks. Polymer network comes from molecular switches and netpoints. Physical or chemical crosslinking determines the shape of permanent polymer network. Physical crosslinking of the polymers is observed in morphology occurring in areas that have at least two segregated domains. High thermal transition temperature of these areas serves as netpoints (a hard segment). Second high thermal transition temperature transition zones acting as molecular switches. The shape memory polymer network are composed of crosslinks or covalent bonds. Physical crosslinking is carried out by crystallization or vitrification of domains  at transition temperature. Shape memory polymers can be easily deformed above the glass transition temperature. A small force is sufficient for the preservation of the temporary shape. Tg is glass transition temperature that is activated that shape memory effect in shape memory polymer. Shape memory polymer below Tg is rigid, glassy state and hard to deform. In this case, soft segment of the shape memory polymer is frozen state.  Significant segmental motion can not be observed in this region. In glassy state, the rigid material is hard to deform. When the shape memory polyurethane heated, material enters the glass transition region. Within this range, the soft segment moves and the heat capacity the shape memory polymer increases.  Polyurethanes, is smart material, gradually increasing attention in recent years due to their shape-memory property. They started to be used widely in the biomedical field such as stent, implant and drug delivery because of its mechanical, thermal, magnetic and biocompatibility properties. Nowadays, especially composite materials, is prepared by using material having magnetic properties, have great interest for use in the medical field. Through these composites, polymeric materials are being developed that show the shape-memory property under a magnetic field. The aim of this study, to be used in the medical field, synthesizing biocompatible polyurethane (PU) gels showing shape-memory property under magnetic field .In the study; polymeric composite materials formed by polyurethane and magnetite (Fe3O4) will be synthesized. In the synthesis of these composite, polyethylene glycol 300 (PEG300), polyethylene glycol 3000 (PEG3000), and castor oil (CO) as polyol, 1,4-butanediol (BDO) as chain extender, hexamethylene diisocyanate as the isocyanate source (HDI) were used. Castor oil is also crosslinking agent in the synthesis. Any solvent or catalyst are used in the synthesis. Micro magnetite (Fe3O4) was added into synthesized polyurethane films in order to show shape-memory feature under magnetic field except the effect of heat. The magnetite ranges from 0% to 10% amount by weight in the polyurethane. Thus, the percentage of magnetite, under different magnetic field and its effect at various temperature on shape-memory property of the composite materials were investigated. Only the performance of magnetite percentage effect on shape-memory feature was investigated keeping CO / PEG ratio constant in the study. In determining of shape-memory performance of PU containing different percentage of magnetite, bending test, which is relatively simple test, was utilized. With this test, PU films’ shape fixity and shape recovery ratio were determined. CO / PEG ratio of PU films in the synthesis is not changed so that contents of rigid area is the same in all the films. Hence, contents of rigid area is encountered as an invariant parameter in shape-memory performance and its impact is not examined. In the bending test, the effect of the percentage of magnetite on polyurethane’s shape-memory properties were investigated. Due to the biocompatibility of PU films, to investigate the availability of possible biomedical applications, the shape fixity at 40 ° C and shapes recall rates of films were analyzed. Furthermore, bending test results, applied under 40° C and 65° C temperature and magnetic field were compared with each other. Fourier transform infrared (FT-IR) spectroscopy for structural characterization, thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) for thermal characterizationand dynamic mechanical analysis to determine the viscoelastic properties (DMA) devices are used for determining of synthesized magnetite particles PU films’ properties. The swelling behavior of the synthesized PU films in pure water and the percent gel content is determined with the Soxhlet extractor. Average molecular weight of crosslinking density and between the two crosslinks of PU composite films are calculated starting from the DMA data. Contact angle measurement of the synthesized PU films in order to determine the effect of the hydrophilic property of the polyurethane with magnetite additive was performed. Contents of hard segments, crystallinity, transition temperature, crosslinking density and the additive in the film affects shape-memory property of the polyurethane. In this study, the contents of hard segments kept constant, impacts of magnetite additive on the shape-memory properties was investigated. Varying percentage of magnetite in PU films affects crystallinity the transition temperature, and crosslinking density value. Therefore, shape-memory performance varies the percentage of additive. According to the results obtained in the study; increasing magnetite percentages in PU film, caused to decrease shape fixity ratio (Rf) due to hardening of material. On the other hand, shape recovery (Rr) increased by increasing magnetite percentage in the films. In this study, shape recovery step applied at two different temperature, 40 °C and 65 °C, and under magnetic field. The first step of the bending test, the heating step, was at 40 °C or 65 °C and the second step, is cooling step, was performed at 4 °C.  According to the results obtained, Rf and Rr were increased a little with increasing temperature. In order to determine reusability of a sample, its shape memory behavior was determined in ten consecutive measurements by bendin test. Glass transition temperature of all the synthesized PU films are quite lower than the room temperature. As expected, with increasing percentage of magnetite, the density of PU composites showed also an increase. With increasing percentage of additive in the synthesized PU films, the water retention of films became difficult and swelling ratio was decreased. Magnetite additive caused the decrease of the surface hydrophilic properties of the polyurethane films. The overall result of the study is that magnetite added polyurethane films have a great potential for biomedical applications as shape memory material.Yüksek LisansM.Sc

Nd:YAG, Er:YAG VE CO2 lazer ile pürüzlendirme sonrası fluorid uygulamasının süt ve sürekli dişlerde mine erozyonunu önlemede ve fluorid alımını arttırmada etkisinin ın vıtro incelenmesi ve yüzey morfolojisinin SEM ile değerlendirilmesi

1.ÖZETIn vitro olarak yapılan bu çalışmanın amacı süt ve sürekli dişlerde CO2, Er:YAG ve Nd.YAG lazer ile pürüzlendirme sonrası fluorid uygulamasının mine erozyonunu önlemede ve fluorid alımını arttırmada etkisini değerlendirmektir. Bu amaçla 40 adet süt azı dişi, 40 adet küçük azı dişi toplandı. Dişler mesio-distal olarak ikiye bölündü. Her grupta 10 adet mine yüzeyi olacak şekilde toplam 16 grup oluşturuldu. Er:YAG lazer, Er:YAG lazer +APF, Nd:YAG lazer, Nd:YAG lazer +APF, CO2 lazer, CO2 lazer+ APF, APF, kontrol grupları hem süt hem de sürekli dişlerde oluşturuldu. Gruplar 3 gün boyunca günde üç kez 5 dk sitrik asit (pH 2,45), 60 dk yapay tükürükte bekletildi. Her günün sonunda demineralize solüsyona geçen kalsiyum, fosfat miktarı ICP-AES cihazı ile fluorid miktarı ise spektrofotometre ile ölçüldü. Ayrıca örnekler SEM’de değerlendirildi. İstatistiksel analiz için Oneway Anova testi ve Tukey HDS testi kullanıldı. 1. gün sonunda kalsiyum salınımı sürekli dişlerde CO2+APF, Er:YAG ve APF uygulanan gruplarda kontrol grubuna göre düşük bulundu (p0,05). Süt dişlerinde kalsiyum, fosfat ve fluorid salınımı açısından deney grupları ile kontrol grubu arasında istatistiksel olarak fark bulunmadı (p>0,05). Sürekli dişlerde fluorid salınımı APF ve CO2+APF gruplarında kontrol grubuna göre düşük bulundu (p0,05). Again no statistically differences in calcium, phosphate, fluoride loss were detected between the experiment groups and control at primary teeth (p> 0,05). Statistically differences were found fluoride loss between CO2+APF, APF and control groups at permanent teeth (p<0,05). Statistically differences were found between the days both primary and permanent teeth (p<0,05). SEM observation showed that lased areas were not thermally degenerated. As a conclusion laser and fluoride application may prevent enamel erosion by enhances the fluoride uptake but this effect is limited.Keywords: CO2 laser, Er:YAG laser, enamel erosion, fluoride, Nd:YAG lase

Giresun Yöresine Ait Bazı Pekmez Türlerindeki Mineral Maddelerin İyon Kromatografi ve ICP-MS Yöntemleriyle Tayinleri

Tez (Yüksek lisans) -- Giresun Üniversitesi. Kaynakça var.vııı , 37 s. : 28 cm.Demirbaş: 0063344