EBSD characterization of deformation in high strain rate application aluminum alloys

Advances in materials characterization tools and techniques are contributing to an improved physics based understanding pertaining to the characteristic behavior of engineering alloys. Aluminum alloys, such as 2139, 2519, 5083, and 7039 are commonly used for lightweight armor applications where resistance to high strain rate deformation is paramount. Failure of these materials is often attributed to the onset of shear band formation. This study was aimed at complimenting the constituent predictive models that describe the mechanical behavior of these alloys using Electron Backscatter Diffraction techniques as a means of microstructural characterization. As such, a quantitative microstructural metric was developed that describes the process by which damage accumulates within the material during high strain rate deformation

Sığır veziküler bezinin morfometrik ve stereolojik olarak değerlendirilmesi

The vesicular gland is an important genital gland related to the fertility of bovine. In this study, the morphometric and stereological methods were sought to adapt to the bovine vesicular gland. For this aim, 8 healthy Holstein bull’s paired vesicular glands were collected from the slaughterhouse. The weight and the dimensions of the glands were measured before the fixation. After the formalin fixation, all the glands were divided into 3 subgroups for the total volume estimation of the gland, cell counting and the volume estimation of the cell nucleus. The cell counting and the volume estimation of the cell nucleus were performed on the principal cells. The average weight, width, length, height, the volume of the glands, the mean number and nucleus volume of the principal cells were 30.9 g., 2.62 cm, 8.86 cm and 1.86 cm, 29.7 cm3 , 3.58.109 and 108 µm3 , respectively. The researchers believe that the findings will contribute to the literature and in particular, facilitate experimental and toxicological researches performed in the future.Veziküler bez sığır fertilitesinde önemli bir üreme bezidir. Sunulan bu çalışmada sığır veziküler bezinin morfometrik ve stereolojik olarak incelenmesi amaçlanmıştır. Bu amaçla 8 sağlıklı Holstein boğasının çift olan veziküler bezleri mezbahadan toplanmış ve ağırlığı ile boyutları ölçülmüştür. Formaldehit tespitinden sonra tüm bezler bezin toplam hacminin, hücre sayısının ve çekirdek hacminin ölçülmesi için 3 alt gruba ayrılmıştır. Hücre sayımı ve hücre çekirdek hacmi ölçümü bezin en çok bulunan ana hücresi olan principal hücreler üzerinde gerçekleştirilmiştir. Bezin ortalama ağırlığı, eni, uzunluğu, yüksekliği, ortalama hacmi, principal hücrelerin ortalama sayısı ve ortalama çekirdek hacmi sırasıyla 30,9 gr., 2,62 cm, 8,86 cm, 1,86 cm, 29,7 cm3 , 3,58,109 ve 108 µm3 olarak bulunmuştur. Araştırmacılar bu bulguların literature katkı sağlayacağına ve gelecekte yapılacak olan deneysel ve toksikolojik çalışmalara ışık tutacağına inanmaktadır

Kounis Syndrome together with Myocardial Bridging Leading to Acute Myocardial Infarction at Young Age

Kounis syndrome, also named as “allergic angina syndrome,” is a diagnosis in which exposure to an allergen causes mostly coronary spasm and rarely plaque rupture, resulting in ischemic myocardial events. Myocardial bridging is defined as an intramural segment of a coronary artery and its systolic compression by overlying fibers. Myocardial bridging generally has a benign prognosis and mostly affects the mid portion of left anterior descending coronary artery. However, some cases with myocardial ischemia, infarction, and sudden death have also been reported. A 17-year-old boy presented to the clinic with acute anterolateral myocardial infarction after having first dose of clindamycin and diagnosed as Kounis syndrome. Further diagnostic workup of the patient showed myocardial bridging at the mid left anterior descending artery. In this report, we present the combination of Kounis syndrome and myocardial bridging leading to myocardial infarction at young age

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

The Role of Supply Chain Transparency among Supply Chain Analytics Capabilities

Nowadays, to take advantage the huge amounts of data collected, companies have started to adapt analytics tools to useful insight their operations and their service level. Such companies attempt to learn from collected data about current and historical processes to define future operational decisions. Even though the importance of supply chain analytics and data-driven decision-making capabilities is recognized by companies, there is a lack of empirical studies. This study demonstrates the role of supply chain transparency (SCT) in the relation between analytics capabilities. The data were gathered from the online survey and were analyzed with partial least squares structural equation modeling (PLS-SEM) using smart-PLS. The results suggest that the existence of significant relation between analytical capabilities in plan, source and make and the mediating effect of supply chain transparency

İsviçre esmeri ineklerde geçiş döneminde vitamin, iz element uygulamalarının fertiliteye etkisinin araştırılması

This study examined the effects of injectable vitamin and trace element combination during the transition period on clinical-biochemical parameters and reproductive performance in Brown Swiss dairy cows. Sixty multiparous cows were randomly allocated two groups as trace element-vitamin treated (n=30) and control (n=30). Animals received four injections at the beginning of the dry period, 21 days before parturition, the day of parturition, and postpartum 30±5 days. Energy, protein, hepatic metabolism markers, blood mineral levels concentrations were measured at -7±4 days antepartum, 3±2 days, and 30±5 days postpartum. Genital tract examinations were performed at 30±5 day postpartum. Treated cows showed lower glucose, total protein, urea, and greater NEFA concentration -7±4 days relative to calving. Effect of vitamin and trace element on serum calcium and phosphorus levels were significant. The total pregnancy rate was 95.8% and 59.09%, in treatment and control groups respectively at 150 days postpartum (P<0.05). In conclusion, trace element and vitamin supplementation increased pregnancy rate significantly and treatment positively affected energy, ion metabolism, and hepatic function.Bu çalışmada geçiş dönemi boyunca vitamin ve iz element enjeksiyonlarının, klinik-biyokimyasal parametreler, periparturent dönem sorunları ile fertilite parametrelerinin üzerine etkisinin araştırılması amaçlandı. Altmış inek, iz element ve vitamin enjeksiyonu yapılanlar (n=30) ve kontrol grubu (n=30) olarak rastgele iki gruba ayrıldı. Vitamin ve iz element enjeksiyonları kuru döneme girişte, doğumdan 21 gün önce, doğumun gerçekleştiği gün ve doğumu izleyen (30±5). günlerde gerçekleştirildi. Enerji, protein, karaciğer metabolizması belirteçleri ile mineral düzeyleri doğum öncesi 7±4. gün, doğum sonrası 3±2. gün ve 30±5. günlerde ölçüldü. Genital organ muayeneleri doğum sonrası 30±5. günde gerçekleştirildi. Uygulama grubundaki inekler kontrol grubundakilere kıyasla doğum öncesi 7±4 günde daha düşük glikoz, toplam protein, üre ve daha yüksek NEFA konsantrasyonu gösterdi. Vitamin ve iz element uygulamasının serum kalsiyum ve fosfor düzeylerine etkisi önemli düzeydeydi. Doğum sonrası 150. günde toplam gebelik oranı uygulama ve kontrol gruplarında sırasıyla % 95.8 ve % 59.09 olarak saptandı (P<0.05). Sonuç olarak, iz element ve vitamin uygulanan ineklerde toplam gebelik oranının belirgin olarak arttığı ve uygulamaların enerji, iyon metabolizması ve karaciğer fonksiyonlarını olumlu etkilediği belirlendi

Zygomatic abscess with temporomandibular joint effusion complicating acute otitis media

WOS: 000386676300007The incidences of extracranial and intracranial complications of acute otitis media (AOM) in children have markedly decreased in the postantibiotic era. Zygomatic abscesses are the rarest type of abscesses originating from mastoiditis. This paper presents a case with a zygomatic abscess as a complication of acute coalescent mastoiditis in a 7-year-old girl who underwent cortical mastoidectomy and myringotomy-ventilation tube insertion

A Study Related to Effects of the Brucellosis on Osteoporosis

Brucellosis is one of the infectious diseases that may increase osteoporosis risk. Bone formation and destruction markers analyzed in the examination of osteoporosis risk. There been many studies on the effect of a variety of diseases on the bone, but no studies have conducted for brucellosis. This study is one of the rare studies showing the effect of brucellosis on a bone. The purpose of this study is that whether age, agglutination level, having brucellosis at the time or before, and gender knowledge of patients have effects on osteoporosis by using bone formation and destruction markers. Between 01/04/2015 and 31/12/2017, blood samples were taken from 40 patients with brucellosis and seven patients whose treatment completed at least six months before. Then biochemical markers were studied on these blood samples. ELISA washer and reader (Biotek, Novatek, Istanbul, Turkey) was used to obtain the values of bone formation and destruction markers. There was a significant difference, according to H. Osteocalcin (Human Osteocalcin/Bone Gla Protein), in terms of bone formation markers and was higher in women. Having brucellosis at the time was significant according to Human deoxypyridinoline (DPD) and Human C-telopeptide of type I collagen (CTX-I) in terms of bone destruction markers and was higher in brucellosis. The bone formation and destruction markers strongly correlated with each other in the same direction. It is thought that brucellosis can increase bone destruction markers, especially DPD (Human deoxypyridinoline) and CTX-I; therefore, osteoporosis risk in brucella patients can reduce by implementing a treatment plan that closely monitors bone destruction markers

Evaluation of high temperature performance of SBS + Gilsonite modified binder

SBS is a widely used polymer modifier for asphalt binders to improve the performance properties of hot mix asphalt. SBS is nearly indispensable when the binder properties do not satisfy the specification requirements under hot service temperatures. One of the concerns in using such additives, however, is the increased cost especially for large-sized construction projects. If a natural modifier can be used to replace some portion of industrial modifier products, such as SBS, it would significantly help reduce the cost of pavement construction. In this study, Gilsonite, a natural asphalt, is used as a binder modifier to reduce the SBS content based on a series of rheological testing. While studies on various properties of binder that is modified only by Gilsonite are common, we investigate the effect of combining SBS and Gilsonte in the same base binder. In the first phase, the binders modified individually with SBS and Gilsonite are evaluated in terms of based on the outcomes of dynamic shear rheometer and rotational viscosimeter tests. Then, the asphalt binders including both SBS and Gilsonite at different contents are subjected to the same rheological testing. The results show that around 3–4% times more Gilsonite is needed to replace 1% of SBS when the two modifiers are mixed in the same binder depending on the Gilsonite/SBS ratio selected. Besides, the viscosity of modified binders with a percent of SBS replaced with Gilsonite is always lower than that of SBS-only modified binder. It is suggested that Gilsonite can be used as an alternative modifier to reduce the cost of asphalt mixture production and compaction in the field

Meaning in life, religious coping, and loneliness during the coronavirus health crisis in Turkey

Since December 2019, the COVID-19 pandemic has caused serious mental health challenges and consequently the Turkish population has been adversely affected by the virus. The present study examined how meaning in life related to loneliness and the degree to which religious coping strategies mediated these relations. Participants were a sample of 872 adults (242 males and 360 females) drawn from general public in Turkey. Data were collected using Meaning in Life Questionnaire, UCLA Loneliness Scale, and the Religious Coping Measure. Meaning in life was associated with more positive religious coping and less negative religious coping and loneliness. Positive religious coping was associated with less loneliness, while negative religious coping was associated with more loneliness. Religious coping strategies mediated the impact of meaning in life on loneliness. These findings suggest that greater meaning in life may link with lesser loneliness due to, in part, an increased level of positive religious coping strategies and a decreased level of negative coping strategies.Ataturk University SBA-2020-859