"Hanedan" Alman basınında:Kanuni Sultan Turgut, Hürrem Sultan Semra

Taha Toros Arşivi, Dosya No: 47-Turgut ÖzalUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010

D-dimer levels and acute pulmonary embolism development in COVID-19 patients

Objective. To identify those who develop pulmonary embolism with Ddimer levels by evaluating pulmonary CT angiographies of patients who are followed up with suspicion of coronavirus disease 2019 (COVID-19). Methods. Patients who were followed up in a community hospital with suspicion of COVID-19 and underwent Pulmonary CT angiography examination were evaluated. Clinical and demographic parameters and DDimer values for patients with and without pulmonary embolism were evaluated in the pulmonary CT angiogram. Results. During the COVID-19 pandemic, Thorax CT examination was performed in our center for suspicion or follow-up of COVID-19 infection in 3396 patients. Pulmonary CT angiography was applied to 312 (9.2%) of these cases. Of these 312 patients, 141 were identified as COVID-19 patients. Acute pulmonary embolism was detected in 33 (23.4%) of 141 patients with COVID-19 and pulmonary CT angiogram. D-dimer levels (5964.97±4036.8 μg/L) of patients with COVID-19 infection and pulmonary embolism were significantly higher than D-dimer levels (972.4±1766.8 μg/L) of patients without pulmonary embolism. In patients with COVID-19 infection, a Ddimer value higher than 1013 μg/L was determined as a cut-off value with 100% sensitivity for the presence of pulmonary embolism. Conclusions. For those struggling with the COVID-19 pandemic, pulmonary embolism should be kept in mind if D-dimer values increase more than expected in the presence of respiratory distress that Thorax CT findings cannot explain

On-line new event detection and clustering using the concepts of the cover coefficient-based clustering methodology

Cataloged from PDF version of article.In this study, we use the concepts of the cover coefficient-based clustering methodology (C3 M) for on-line new event detection and event clustering. The main idea of the study is to use the seed selection process of the C3 M algorithm for the purpose of detecting new events. Since C3 M works in a retrospective manner, we modify the algorithm to work in an on-line environment. Furthermore, in order to prevent producing oversized event clusters, and to give equal chance to all documents to be the seed of a new event, we employ the window size concept. Since we desire to control the number of seed documents, we introduce a threshold concept to the event clustering algorithm. We also use the threshold concept, with a little modification, in the on-line event detection. In the experiments we use TDT1 corpus, which is also used in the original topic detection and tracking study. In event clustering and event detection, we use both binary and weighted versions of TDT1 corpus. With the binary implementation, we obtain better results. When we compare our on-line event detection results to the results of UMASS approach, we obtain better performance in terms of false alarm rates.Vural, AhmetM.S

Sülfürik asitle muamele edilmiş fındık zurufu ile kurşun (ii) ve mangan (ii) iyonlarının adsorpsiyonu

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Bu çalışmada, fındık zurufundan sülfürik asitle muamele edilerek hazırlanan aktif karbon üzerine, sulu çözeltilerden kurşun (II) ve mangan (II) iyonlarının adsorpsiyonu incelendi. Adsorpsiyon deneyleri kesikli yöntem kullanılarak yapıldı. Çözelti pH'ı, karıştırma süresi, dozaj etkisi, sıcaklık ve başlangıç konsantırasyonu gibi adsorpsiyonda etkili parametreler incelendi. Elde edilen adsorpsiyon verileri Langmuir ve Freundlich adsorpsiyon izotermlerine uygulandı. Kurşun (II) ve mangan (II) iyonlarının adsorpsiyon kinetiği ve termodinamiği incelendi. Adsorpsiyon verileri kullanılarak tek kademeli kesikli adsorpsiyon sistemi dizayn edildi.In this study, adsorption of lead (II) and manganese (II) ions from aqueous solutions on the activated carbon prepared from hazelnut husks by treating with sulphuric acid. Adsorption experiments were carried out by batch technique. Effective parameters on the adsorption such as solution pH, contact time, dosage, temperature and initial concentration were investigated. The obtained adsorption data were applied to Langmuir and Freundlich adsorption isotherms. Adsorption kinetics and thermodynamics of lead (II) and manganese (II) ions were investigated. A single stage batch adsorbent was designed by using adsorption data

Design, Analysis and Performance Evaluation of Electrical Power Subsystem based on Triple-Junctions Solar PV Cells and SEPIC for a Conceptual 1u Cubesat Mission

This study aims to popularize low voltage power supply design especially for space satellite Cubesat mission and other portable consumer electronic devices. In this context, a preliminary design of an electrical power subsystem (EPS) is carried out for a conceptual 1u Cubesat mission in this paper. Mathematical modeling of the basic elements of the EPS is presented. Photovoltaic (PV) power generation system that is selected is made up of triple-junction solar cells, and the battery charging system based on lithium technology as well as the power conditioning converters are selected based on single ended primary inductance converter topology popularly abbreviated as SEPIC. Triple-junction solar PV cell results are verified by comparing with the datasheet values. A maximum power point tracking algorithm which is known as perturb and observe is implemented and proportional-integral controller is used for the SEPIC. All of these are well analyzed, mathematically modeled and simulated. Feasibility of the designed EPS is verified by comparing with similar devices from different manufacturers

Postępująca kardiomiopatia nieniedokrwienna powodująca nadczułość załamka T i nieprawidłową stymulację — opis przypadku

T-wave oversensing is one of the causes of inappropriate shocks. It results from various conditions including progressive cardiomyopathy, diminution of R-wave amplitude and relative or dynamic gain in the T-wave amplitude, electrolyte abnormalities, injury current-related increase in the T-wave voltage. We report a 59-year-old patient who presented with implantable cardioverter defibrillator shocks after 5 year implantation with decreased R-wave amplitude and T-wave changes on 12-lead electrocardiography.Nadczułość załamka T jest jedną z przyczyn nieprawidłowej stymulacji. Może być ona spowodowana różnymi zaburzeniami, takimi jak postępująca kardiomiopatia, zmniejszenie amplitudy załamka R i względne lub dynamiczne zwiększenie amplitudy załamka T, zaburzenia elektrolitowe oraz zwiększenie woltażu załamka T spowodowane prądem uszkodzenia. Przedstawiono przypadek 59-letniego chorego z wszczepionym 5 lat wcześniej kardiowerterem-defibrylatorem serca, u którego stwierdzono w 12-odprowadzeniowym elektrokardiogramie zmniejszoną amplitudę załamków R i zmienione załamki T

The experimental analysis of the fatigue strength of the spot welded different steel sheets

Nokta direnç kaynağı, imalat sektöründe oldukça yaygın olarak kullanılan bir kaynak yöntemidir. Özellikle otomotiv ve beyaz eşya sektöründe imalatın en önemli aşamalarını bu kaynak yöntemi oluşturmaktadır. Bu tip bağlantılar, işletme sırasında statik ve dinamik yükler altında zorlanmaktadır. Özellikle dinamik yükler altında zorlanan bölgelerde oluşan hasar tipi oldukça kritik olup, bunlar yorulma hasarı olarak adlandırılırlar. Yorulma hasarı, malzeme içerisindeki bir hata veya süreksizlikten başlar, giderek ilerler ve sonunda hasarla sonuçlanır. Nokta kaynaklı bölgeler de, doğal bir çentik etkisi yapmaktadır ve dolayısıyla da yorulma hasarı açısından oldukça kritik bölgeler olarak karşımıza çıkmaktadır. İmalatta, sadece aynı özelliğe sahip saclar değil, maliyet ve konstrüktif açıdan farklı bileşime ve özelliğe sahip saclar da birbirleriyle nokta kaynağı yardımıyla kaynak edilmektedir. Bu tip nokta kaynaklı bölgelerde ortaya çıkabilecek problemlerin ve bunların yorulma dayanımlarının belirlenmesi büyük önem taşımaktadır. Bu çalışmada, galvanizli ve ostenitik paslanmaz çelik saclar, hem kendi aralarında hem de birbirleriyle nokta kaynağı ile birleştirilmişlerdir. Her malzeme kombinasyonu için 3 farklı nokta çapına sahip numuneler elde edilmiştir. Kaynaklı numunelere uzun ömürlü yorulma deneyleri yapılmış ve her deney numunesi için S-N (kuvvet – çevrim sayısı) eğrileri elde edilmiştir. Galvanizli çelik saclardan oluşan kaynaklı bağlantılar en yüksek yorulma dayanımına sahip bağlantılardır. En düşük yorulma ömrüne sahip bağlantı ise galvanizli çelik – ostenitik paslanmaz çelik sac bağlantılardır. Bu bağlantı tipi üzerinde, yorulma sonrası çekirdek çapı ölçümleri yapılmıştır. Bu bağlantı tipi için, Paris–Erdoğan çatlak ilerleme hızı bağıntısını veren malzeme sabitleri belirlenmiştir.  Anahtar Kelimeler: Paslanmaz çelik, galvanizli çelik, nokta kaynağı, yorulma. Resistance spot welding is a weld process which is widely used in the manufacturing areas. In the most important levels of the steel sheet constructions and especially automotive industry, the resistance spot welding is used. This type welded joints are exposed to static and dynamic forces during the operations. The failure type which occurs during dynamic forces is the most critical failure type, and it is called as fatigue failure. A fatigue failure starts from the material surfaces or a defect in the material. This defect becomes a crack during the operation, it propagates and finally the material fractures. Because the resistance spot welded areas are a natural notch, they behave like a defect or crack initiation. And thus those welded areas are most critical joints in fatigue failure. Corrosion is one of the most important problems in the steel structures. To improve the corrosion resistance, the steel sheets are coated with Zinc, and these Zinc coated steel sheets are called as galvanized steel sheets. To decrease the cost and height, in manufacturing, not only the same sheets but only the different sheets (for example galvanized steel sheets and austenitic stainless steel sheets) are welded to each other by using resistance spot welding. Some problems can occur in spot welded different sheets during the operation, and thus it is very important to investigate those problems, especially fatigue strength of the joints. In this study, galvanized and austenitic stainless steel sheets were joined to each other by using resistance spot welding. The thicknesses of the galvanized steel and austenitic stainless steel are 0.93 and 1.03 mm, respectively. The experiment parameters are sheet combination and weld nugget diameter. Three weld nugget diameters were selected as 4, 5 and 6 mm which are most widely used in the steel sheet joining industry. The pre-tests were performed to investigate the effect of the weld current on the nugget diameter. By using the pre-test results, resistance spot welded steel sheets series were obtained with 4, 5 and 6 mm (± 0.1) nugget diameter, and galvanized ' galvanized steel, galvanized ' austenitic stainless steel. The fatigue tests were performed to spot welded steel sheet specimens. The effects of the material composition on the fatigue strength of the spot welded steel sheets were investigated. The fatigue experiments in this study were performed in a laboratory environment at room temperature (19  25oC) using a 60 kN servo-hydraulic test machine. Specimens were exposed to a constant load amplitude sinusoidal waveform until fracture occurred or to a maximum 1x107 cycles at R value 0.01. The cyclic displacement between specimen holders was measured. The variation of the specimen stiffness was evaluated after each test. Specimen stiffness was defined as DP /Dl. Where DP is the cyclic load range and Dl is the specimen?s cyclic elongation range during fatigue testing. The specimen stiffness decreases as fatigue cracks propagate. Specimen failure was defined at 25% stiffness drop. Some welded specimens which is exposed in high loads failure as rupture. The test frequency was kept constant during the test. By using the fatigue test results, the load range versus number of cycles to failure (S  N) curves were plotted. The results show that galvanized steel sheet combination has the highest fatigue limit. The sheet combination which has the minimum fatigue limit is galvanized  austenitic stainless steel sheet combination. Due to the spot welding nugget formation, the nugget behaves like a surface crack. In this study, to measure the nugget diameter after the fatigue and thus crack length, four identical spot welded specimens with 5 mm nugget diameter, galvanized steel  austenitic stainless steel combination were exposed to fatigue experiment 30000, 60000, 90000 and 104000 number of cycles respectively. After the fatigue tests, the remaining nugget of the welded specimens were measured, and crack lengths were evaluated. According to results, while number of cycles is increased, the crack length and crack growth rate increase. By using the results and measured crack length for spot welded galvanized steel austenitic stainless steel sheet combination, C and m material constant in Paris  Erdogan crack growth rate equation were obtained. The crack growth rate equation for this type spot welded joint were obtained as  Keywords: Stainless steel, galvanized steel, spot welding, fatigue

Low Voltage Battery Management System With Internal Adaptive Charger and Fuzzy Logic Controller

Lithium ion (Li-Ion) and lithium polymer (Li-Po) batteries need to be used within certain voltage/current limits. Failure to observe these limits may result in damage to the battery. In this work, we propose a low voltage battery management system (LV-BMS) that balances the processes of the battery cells in the battery pack and the activating-deactivating of cells by guaranteeing that the operation is within these limits. The system operates autonomously and provides energy from the internal battery. It has a modular structure and the software is designed to control the charging and discharging of eight battery cells at most. A STM32F103 microcontroller is used for system control. The fuzzy logic controller (FLC) is used to set the discharge voltage limit to prevent damage to the battery cells, shorten the settlement time and create a specialized design for charge control. The proposed structure enables solar panel or power supplies with di erent voltage values between 5 V and 8 V to be used for charging. The experimental results show there was a 42% increase in usage time and the voltage di erence between the batteries was limited to a maximum of 65 mV. Moreover, the charge current settles at about 20 ms, which is a much faster response when compared to a PID controller

Clinical value of neutrophil to lymphocyte ratio in the region of lower extremity deep venous thrombosis

Objectives. Many studies have demonstrated a significant association between cardiovascular disease andneutrophil to lymphocyte ratio (NLR). To our knowledge, no study has been reported in patients with deepvenous thrombosis (DVT) which affecting proximal or distal leg. In this study we analyzed proximal and distalDVT according to the NLR. Methods. This retrospective study was obtained from patients’ records of a tertiaryuniversity hospital between May 2011 to January 2014. A total of 57 patients with the diagnosis of acute primaryDVT and 30 patients as control group included in the study. All of them were confirmed with lower extremityvenous duplex examinations. Of these, 37 examinations with the diagnosis of proximal DVT were comparedto 20 examinations with distal DVT. The groups compared regarding to complete blood counter values. Results.Mean eosinophil level was higher in the distal DVT group (0.28±0.24 vs. 0.12±0.01, p=0.001), whereas medianNLR were higher in the proximal DVT group than the distal DVT group (3.5 [0.5-4.3] vs. 2.3 [1.2-9.7],respectively; p=0.002). In addition, median NLR, leukocyte and neutrophil counts were statistically lower inthe control group than the others (p=0.014, p=0.027 and p=0.004, respectively). Conclusion. NLR, aninexpensive and easily measurable laboratory variable, was independently and significantly associated withthe presence and severity of DVT, especially acute proximal DV