Effect of shielding gas on microstructure and mechanical properties in AA6061-T6 alloy MIG welding

Due to its properties such as high strength/weight ratio, enhanced corrosion resistance, low density, AA6061-T6 aluminum alloy welding is widely used in structural, automotive and rail industry. In this study, AA6061-T6 alloy was welded with robotic metal inert gas technique using ER5356 filler wire. The effects of different shielding gas composition ratios (argon/helyum) on the macro / microstructre, mechanical properties (hardness, tensile strength) of the weld joint were investigated. Welding porosity decreased with the addition of helium gas to argon gas. Accordingly, the tensile strength of welded joints increased from 190 MPa to 221 MPa with the addition of helium gas. The strength of the welded joints (190-221 MPa) was obtained lower than that of the base material (290 MPa) due to the changes in the microstructure as a result of the weld thermal cycle and grain coarsening in the heat affected zone. Dentritic, columnar and coarse shaped grains were observed along the weld section, respectively in the weld bead, partially melted zone and heat affected zone. The differentiation of the shielding gas composition did not cause these regions to change, but the heat affected zone expanded with the increase in the helium content. The change in hardness of the cross section of welded joint has increased from around 60 HV to 90 HV from the welding area to the base material. 25% Argon-75% Helium gas mixtures provided optimum combination in terms of microstructure, mechanical properties and cost

SINIRLARI AŞAN DERVİŞLER: BEKTAŞİLİĞİN KÜLTÜREL İLİŞKİLERİ (1826-1925) ÜZERİNE

Cem Kara’nın Sınırları Aşan Dervişler: Bektaşiliğin Kültürel İlişkileri (1826-1925) kitabı, 2017’de tamamladığı ve 2018’de Almanca yayımlanan doktora tezinin (Grenzen überschreitende Derwische: Kulturbeziehungen des Bektaschi-Ordens 1826-1925, Vandenhoeck & Ruprecht) Türkçe çevirisi. Kara’nın bu çalışması, 2018’te Southeast Association Doktora Tezi Ödülü ve 2022’de Annemarie Schimmel Ödülü’nü aldı

Caracterización integral de las propiedades fisicoquímicas, térmicas, composicionales y sensoriales del aceite de semilla de rosa mosqueta prensado en frío

In this study, cold-pressed rosehip seed oil was fully characterized. Acidity and oxidation levels were near the limit values or slightly exceeded them and improvement in the storage conditions was suggested. The oil started to crystallize at -45.25 °C, and melt at -25.56 °C. Linoleic acid (51.1%), β-sitosterol (84.6%), γ-tocopherol (773.76 µg/g) and rosmarinic acid (31.38 µg/g) were determined as major fatty acid, sterol, tocopherol and phenolic compound, respectively. For the first time, aromatic volatile compounds and sensory descriptive terms were determined for cold-pressed rosehip seed oil. Sixty-seven volatile compounds were detected and L-limonene was found to be a major volatile compound. According to the sensory analysis, timber/kindling and raw vegetable tastes/aromas were found to be relatively dominant. Consequently, it is thought that rosehip seeds can be used as a raw material for edible and nutritionally-rich cold-pressed oil production and/or as source oil for functional food preparations.En este estudio se caracterizó completamente el aceite de semilla de rosa mosqueta prensado en frío. Los niveles de acidez y oxidación estaban cerca de los valores límite o los excedían ligeramente y se sugirió mejorar las condiciones de almacenamiento. El aceite comenzó a cristalizar a -45,25°C y a fundirse a -25,56°C. Se determinó el ácido linoleico (51,1%), β-sitosterol (84,6%), γ-tocoferol (773,76 µg/g) y ácido rosmarínico (31,38 µg/g) como principal ácido graso, esterol, tocoferol y compuesto fenólico, respectivamente. Por primera vez, se determinaron compuestos aromáticos volátiles y términos descriptivos sensoriales para el aceite de semilla de rosa mosqueta prensado en frío. Se detectaron sesenta y siete compuestos volátiles y se descubrió que el L-limoneno era un compuesto volátil importante. Según el análisis sensorial, se encontró que los sabores/aromas de madera/astillas y vegetales crudos eran relativamente dominantes. En consecuencia, se cree que las semillas de rosa mosqueta pueden usarse como materia prima para la producción de aceite prensado en frío comestible y nutritivo y/o como aceite fuente para preparaciones de alimentos funcionales

Puntos de vista de Maestros de Educación Física y Deportes que implementaron por primera vez un informe relacionado con el estado de la salud

The Health-Related Fitness Report Card (HRFRC) has been implemented first-time by physical education and sports teachers in the 2016-2017 academic year under the leadership of the Ministry of National Education in Turkey. The purpose of this study was to obtain the views of the physical education and sports teachers on the first time implemented HRFRC and the content of the fitness test. Participants were composed of 10 physical education and sports teachers with seniority between 2 and 30 years and actively working in the middle and high schools. Semi-structured in-depth individual interviews and field notes were chosen as the data collection tools. Collected data were analysed using the content analysis method. Identified themes are (1) Benefits of the Practice, (2) Reasons for Not Achieving the Objective of the Practice, (3) Challenges Experienced with the Practice, and (4) Recommendations for the Practice. Teachers emphasized that improving the quality of HRFRC training provided by the government, using standard materials for measurements, changing the time of the implementation, increasing the integration of stakeholders such as a nutritionist, health experts and families into implementation and providing a more confidential atmosphere in the implementation for increasing participation rate and the quality of the HRFRC.El Informe de estado físico relacionado con la salud (HRFRC) ha sido implementado por primera vez por profesores de educación física y deportes en el año académico 2016-2017 bajo la dirección del Ministerio de Educación Nacional en Turquía. El propósito de este estudio fue obtener los puntos de vista de los profesores de educación física y deportes en la HRFRC implementada por primera vez y el contenido de la prueba de aptitud física. Los participantes estuvieron compuestos por 10 maestros de educación física y deportes con antigüedad de entre 2 y 30 años y trabajando activamente en las escuelas intermedias y secundarias. Se eligieron entrevistas individuales en profundidad semiestructuradas y notas de campo como herramientas de recopilación de datos. Los datos recopilados se analizaron mediante el método de análisis de contenido. Los temas identificados son (1) Beneficios de la práctica, (2) Razones para no lograr el objetivo de la práctica, (3) Desafíos experimentados con la práctica y (4) Recomendaciones para la práctica. Los docentes enfatizaron que mejorar la calidad de la capacitación HRFRC brindada por el gobierno, usando materiales estándar para mediciones, cambiando el tiempo de implementación, aumentando la integración de partes interesadas como nutricionista, expertos en salud y familias en la implementación y proporcionando una atmósfera más confidencial en la implementación para aumentar la tasa de participación y la calidad de la HRFRC

Investigation of the Anti-Cancer Effects of B-asaron and Etoposide in MCF-7 Breast Cancer Cells

Currently, the options available for the treatment of various cancers including breast cancer, are associated with several limitations such as severe toxicity, drug resistance, poor prognosis, and high risk of recurrence. Therefore, there appears to be an increasing interest and necessity in investigating various phytochemicals from natural sources for a superior and safer alternative treatment strategy. The bioactive phytochemical alpha (alpha%253B) and beta (beta%253B)-asarone from Acorus calamus is a traditional medicine system that has been shown to have anti-tumor and chemo-inhibitory activities in numerous preclinical studies both in vitro and in vivo. Various experimental studies with human malignant cell lines and animal models have also confirmed the anti-tumor and anti-cancer activities of beta%253B-asarone. In this study, we aimed to investigate the anti-cancer effects of beta%253B-asarone alone or together with etoposide buy measuring cellular responses such as cell viablity, cell cycle arrest and apoptosis using breast cancer cell line MCF-7 cells. In order to get insight in to the mechanism, we also tested the expression of of NF-kappa%253BB %252F p65 activity and the expression of Bcl-2 family member pro-apoptotic Bax protein together with p53 and p21 activities in response to beta%253B-asarone alone or together with etoposide treatment. As a result, it was concluded that the use of beta%253B-asarone alone in breast cancer cells is effective in reducing cell viability, but when used together with Etoposide, it does not cause a synergistic effect. Here we suggest that that in particular activation of NF-kB%252Fp65 may be lead resistance to etoposide treatment

Investigating the association between ınternet addiction, depression, social phobia, social anxiety and psychiatric disorders among secondary education students in Turkey

Introduction: The purpose of the study is to identify the prevalence of Internet addiction (IA) among students and evaluate the association of IA with depression, social phobia, social anxiety and psychiatric disorders. Materials and Methods: A total of 297 students aged 9-14 years and studying at a private school in Gölbaşı/Ankara province were included in the study. The study was conducted between November 2015 and May 2016. The student’s depression inventory; social phobia scale for student and adolescents; social anxiety scale for student-revised and strength and difficulties questionnaire were used as data collection tools. According to the Internet dependency scale, student were classified into 4 groups as non-addicted group, threshold group, risk group and addicted group. Results: According to the Internet dependency scale, the majority (258/86.9%) of the students were not Internet addicts. Twenty seven (9.1%) students were in the threshold group and 12 (4%) student were in the risk group. Compared with the depressed mood, the likelihood of having depression in the risk group was higher (p=0.001). The risk group and the threshold group had higher social phobia and social anxiety scores at a statistically significant level than the non-dependent group (p?0.05). Conclusion: Internet use is an indispensable element for the lives of generation-Z student. However Internet addiction, which is directly related to this condition, causes many psychological and social problems for student at an alarming level. These problems cannot be ignored and can be avoided by rational use of the internet. © 2022, Galenos Publishing House. All rights reserved.Finansal Destek: Yazarlar tarafından finansal destek almadıkları bildirilmiştir

Sleep stage and obstructive apneaic epoch classification using single-lead ECG

<p>Abstract</p> <p>Background</p> <p>Polysomnography (PSG) is used to define physiological sleep and different physiological sleep stages, to assess sleep quality and diagnose many types of sleep disorders such as obstructive sleep apnea. However, PSG requires not only the connection of various sensors and electrodes to the subject but also spending the night in a bed that is different from the subject's own bed. This study is designed to investigate the feasibility of automatic classification of sleep stages and obstructive apneaic epochs using only the features derived from a single-lead electrocardiography (ECG) signal.</p> <p>Methods</p> <p>For this purpose, PSG recordings (ECG included) were obtained during the night's sleep (mean duration 7 hours) of 17 subjects (5 men) with ages between 26 and 67. Based on these recordings, sleep experts performed sleep scoring for each subject. This study consisted of the following steps: (1) Visual inspection of ECG data corresponding to each 30-second epoch, and selection of epochs with relatively clean signals, (2) beat-to-beat interval (RR interval) computation using an R-peak detection algorithm, (3) feature extraction from RR interval values, and (4) classification of sleep stages (or obstructive apneaic periods) using one-versus-rest approach. The features used in the study were the median value, the difference between the 75 and 25 percentile values, and mean absolute deviations of the RR intervals computed for each epoch. The k-nearest-neighbor (kNN), quadratic discriminant analysis (QDA), and support vector machines (SVM) methods were used as the classification tools. In the testing procedure 10-fold cross-validation was employed.</p> <p>Results</p> <p>QDA and SVM performed similarly well and significantly better than kNN for both sleep stage and apneaic epoch classification studies. The classification accuracy rates were between 80 and 90% for the stages other than non-rapid-eye-movement stage 2. The accuracies were 60 or 70% for that specific stage. In five obstructive sleep apnea (OSA) patients, the accurate apneaic epoch detection rates were over 89% for QDA and SVM.</p> <p>Conclusion</p> <p>This study, in general, showed that RR-interval based classification, which requires only single-lead ECG, is feasible for sleep stage and apneaic epoch determination and can pave the road for a simple automatic classification system suitable for home-use.</p

Ischemia modified albumin is an indicator of oxidative stress in multiple sclerosis

Introduction: Oligodendrocytes need iron in processes of energy generation and myelination. However, excessive levels of iron may exert iron induced oxidative stress and thus lead to tissue degeneration. Monitoring oxidative stress will be of paramount importance in follow-up of patients with many diseases including multiple sclerosis (MS). The aim of this study was to measure total anti-oxidative status (TAS), total oxidative status (TOS) and ischemia modified albumin (IMA) in stable relapse remitting MS (RRMS) patients. Materials and methods: Thirty-five RRMS patients (15 males and 20 females; median age 42 (20-55) years) and thirty-five age-sex matched healthy controls (13 males and 22 females; median age 37 (21-60) years) were included in this study. All patients were diagnosed with MS according to the criteria of McDonald. Results: IMA levels were significantly higher in RRMS patients (P < 0.001), while TAS and TOS did not show any significant difference between groups (P = 0.870 and P = 0.460, respectively). Conclusions: Our results suggest IMA as a more efficient serum marker than TAS and TOS in detecting the oxidative stress in MS patients. Serum oxidative stress markers should be included in future study protocols besides clinical and radiological parameter

Usporedba uporabe tradicionalnih i digitalnih tehnika vizualizacije u obrazovanju za dizajn za okoliš

The rapid advances in computer technology rendered the use of the new technologies in professional disciplines such as visual arts, design, architecture and planning, where visualization is utilized prominently i.e. is a requirement. However, applications such as using conventional design tools and graphical presentation techniques, sketching, drawing plans, sections, perspectives on paper and creating models are still used in landscape architecture, architecture, interior architecture or in departments that rely on planning. Digital technologies, on the other hand, are used as supplementary tools. The aim of the present article was to determine the methods utilized predominantly in different stages of environmental design studio in landscape architecture education and the advantages and disadvantages of the utilized conventional and digital presentation techniques, and to compare the developing visualization software. In this context, the level of satisfaction of the students with these methods were determined. The study was conducted with students in the Landscape Architecture Department attending Karadeniz Technical University (KTU). The study findings demonstrated that the satisfaction levels of architecture students with digital technologies were higher when compared to conventional methods due to the facilities and superior qualities provided by the digital technologies.Brzi napredak računalne tehnologije omogućio je uporabu novih tehnologija u profesionalnim disciplinama kao što su likovna umjetnost, dizajn, arhitektura i prostorno planiranje u kojima se dominantno oslanjamo na vizualizaciju. Preciznije, vizualizacija je potreba. Međutim, primjena tradicionalnih alata za dizajn i za tehnike grafičkog prikazivanja, skiciranja, iscrtavanja planova, profili, perspektive na papiru i izrada modela još uvijek se koriste u arhitekturi okoliša, arhitekturi, unutarnjoj arhitekturi ili u granama koje ovise o planiranju. Digitalne tehnologije, s druge strane, koriste se kao dodatni alati. Cilj ovoga rada je odrediti koje se metode dominantno koriste u različitim fazama u studiju dizajna za okoliš u obrazovanju za arhitekturu okoliša te usporediti razvijene programe za vizualizaciju. U tom kontekstu određena je razina zadovoljstva studenata s tim metodama. Istraživanje je provedeno sa studentima s Odjela za arhitekturu okoliša pri Sveučilištu Karadeniz Technical University (KTU). Rezultati istraživanja pokazali su da su razine zadovoljstva studenata arhitekture s digitalnim tehnologijama više u usporedbi s tradicionalnim metodama zbog uvjeta i superiorne kvalitete koju nude digitalne tehnologije

Effects of Starter Culture Combination on the Characteristic of White Cheese

In this study, the effects of using mesophilic and thermophilic cheese cultures at different ratios on White cheese yield, physico-chemical, textural, sensory and microbiological properties were investigated. Yeast, mold, Enterobacter spp., and Staphylococcus aureus counts were determined. In sample with high ratio of thermophilic culture, there was slightly increase in fat, salt, fat and salt in dry matter content. All textural parameters were found significantly different. The number of Enterobacter spp. was found lower in cheese with high ratio of thermophilic culture, while the number of yeast was high. As a result, it has been observed that starter culture ratios, which contain different bacterial strains, can affect the technological and functional properties of freshly consumed cheese