Okul dışı STEM atölye çalışmalarına katılan öğrencilerin STEM eğitimine yönelik tutumları

In this study, the attitudes of students toward STEM education were examined according to various demographic characteristics and mixed research method was used. 170 students ranging between 7 and 14 years old participating municipalities in a province outside of school STEM workshops in Turkey constituted the sample of the study. The sampling was determined by non-random sampling method. Data were collected by STEM Attitude Scale adapted to Turkish by Yıldırım and Selvi (2015) and semi-structured interviews with students were conducted in order to get the opinions of the students in detail. Results indicated that out-of-school STEM workshops improve students' attitudes towards STEM. In addition, STEM attitude scores of the students did not differ by gender. It was also investigated whether the scores of the students from STEM attitude scale differ according to mother and father education level. There was only significant difference in engineering sub-dimension of the STEM attitude scale in terms of mother education status. On the other hand, it was determined that STEM attitude scale scores of the students did not differ according to father education status. Semi-structured interviews showed that students had lack of knowledge about STEM education and, also concluded that the achievement of a concrete result for children learning by doing affects their attitudes positively.Araştırmada okul dışı STEM atölye çalışmalarına katılan öğrencilerin STEM eğitimine yönelik tutumları çeşitli demografik özelliklere göre incelenmiştir. Araştırmanın örneklemini Türkiye’deki bir ilin belediyesinde okul dışı STEM atölye çalışmalarına katılan yaşları 7 ile 14 arasında değişen 170 öğrenci oluşturmaktadır. Örneklem seçkisiz olmayan örnekleme yöntemi ile belirlenmiştir. Veri toplama aracı olarak; Yıldırım ve Selvi (2015) tarafından Türkçeye uyarlanmış STEM Tutum Ölçeği ve öğrencilerin görüşlerini detaylı bir şekilde alabilmek için yarıyapılandırılmış görüşmeler yapılmıştır. Sonuçlar, okul dışı STEM atölyelerinin öğrencilerin STEM'e yönelik tutumlarını geliştirdiğini göstermiştir. Ayrıca, öğrencilerin STEM tutum puanlarının cinsiyete göre değişmediği tespit edilmiştir. Öğrencilerin STEM tutum ölçeğinden aldıkları puanların anne ve baba eğitim düzeyine göre farklılık gösterip göstermediği de araştırılmıştır. STEM tutum ölçeğinin mühendislik alt boyutunda annenin eğitim durumu açısından istatistiksel olarak anlamlı bir farklılık bulunmuştur. Öte yandan, öğrencilerin STEM tutum ölçeği puanlarının baba eğitim durumuna göre farklılık göstermediği belirlenmiştir. Yarı yapılandırılmış görüşmeler öğrencilerin STEM eğitimi hakkında yeterince bilgi sahibi olmadıklarını ve aynı zamanda yaparak öğrenen çocuklar için somut bir sonuç elde etmenin onların tutumlarını olumlu yönde etkilediği de tespit edilmiştir

The environmentally induced corrosion failure of cable bolts in underground coal mines

The failure of cable bolts, made from high carbon cold-drawn steel wires, is frequently observed in underground coal mines. Hydrogen-induced stress corrosion cracking (HISCC) is known to be the main mechanism of such a failure. The groundwater and geomaterials (mixture of coal and clay) collected from the affected mines have not been found to be corrosive. In this study, we examine the effect of sulfate-reducing bacteria (SRB), which exist in affected mines, on the failure of cable bolts. We make stressed coupons from cable bolt wires and test the coupons in different solutions containing SRB. We find that the hydrogen sulfide produced by SRB promote hydrogen diffusion into the steel and causes HISCC while the steel is under constant load. The fractures in failed coupons show similar features to those failed in underground coal mines. This study provides insights into the role of microorganisms in the failure of underground structures. We recommend future studies to develop prevention measures to stop hydrogen diffusion into steel or microbial activities around the bolts

YERALTI MADEN İŞLETMELERİNDEKİ MESLEK GRUPLARININ GÜRÜLTÜ MARUZİYETİNİN BELİRLENMESİ

Madencilik dünyanın ve ülkemizin önemli iş kollarından birisidir. Madencilik faaliyetleri esnasında çeşitli fiziksel risk etmenleri ortaya çıkmaktadır. Bu fiziksel risk etmenlerinin başında da gürültü gelmektedir. Teknolojinin gelişimine bağlı olarak günümüzde yeraltı madenciliğinde mekanizasyona geçiş süreçleri hızlanmış ve bu durum da çalışan personelin yüksek gürültü düzeyleri ile karşı karşıya kalmasına neden olmuştur. Gürültü insan üzerinde fizyolojik ve psikolojik birçok etki oluşturmaktadır. Bunların başında da bir meslek hastalığı olan işitme kayıpları gelmektedir. Bu çalışmada, yeraltı kömür madenciliğinde farklı meslek gruplarının iş tanımları yapılmış ve bu meslek gruplarında çalışan personelin maruz kaldığı gürültü düzeyleri belirlenmiştir. Yapılan gürültü ölçümleri gürültü yönetmeliği kapsamında değerlendirilerek gürültüye karşı alınabilecek önlem ve tedbirler açıklanmıştı

Evaluating clinical and laboratory effects of ozone in non-surgical periodontal treatment: a randomized controlled trial

Objective: This study aims to evaluate the clinical and biochemical (oxidative stress and pro-inflammatory mediators) effects of the gaseous ozone use accompanied by scaling and root planning (SRP) in periodontal treatment. Material and Methods: The study population consisted of 40 patients with chronic periodontitis (CP) randomly sorted into two groups of 20. The experimental group received SRP plus 3 watts gaseous ozone in two separate applications five days apart, whereas the control group received SRP plus placebo. Clinical periodontal parameters were assayed and saliva samples were taken before the initial and one month after the second treatment. Periodontal examination assessed plaque index (PI), gingival index (GI), probing depth, and clinical attachment level (CAL). Total antioxidant status (TAS), total oxidant status (TOS), nitric oxide (NO), 8-hydroxy-2'-deoxyguanosine (8-OHdG), myeloperoxidase (MPO), glutathione (GSH), malondialdehyde (MDA), and transforming growth factorbeta (TGF-β) levels were evaluated from saliva samples. Results: Changes following treatment in PI, GI, probing depth, and CAL scores were similar for both groups (p>0.05). Of note, TGF-β levels were observed to be higher in the treatment group than in controls (p<0.05). Changes in 8-OHdG, TAS, TOS, NO, MPO, GSH and MDA levels, however, were not significantly different between groups (p>0.05). Conclusion: The findings of this study indicate that SRP plus gaseous ozone versus SRP alone does not correlate to a significant improvement in periodontal recovery

Analysis of potential predatory journals in radiology

PurposeThe aim of this study is to determine the presence and evaluate the features of potential predatory journals in the radiology field.MethodsThe presence of the keywords related to radiology listed in the name of journals was investigated in Beall’s list. We have searched and recorded the features and the information of the included journals listed under the following headings: address and location, publishing features, editorial board, indexing features, submission, and peer-review processes.ResultsA total of 66 radiology journals from 27 publishers were identified from the updated version of the original Beall's list. Regarding the publishers, 33 journals (50%) reported an address in the United States of America, while others were from United Kingdom, India, Hong Kong, Iran, and Canada. While 44 journals' (67%) website reported a contact address, no addresses were declared in the website of 21 journals (32%). The median time of publication activity was 3.5 years (interquartile range [IQR], 1–5 years; range, 0–16 years). Thirty-five journals (53%) indicated their publication ethics policy on the website. Forty-seven (71%) journals reported a regular editorial board (EB) list. The competency of the EB was considered as "inappropriate" in 27 (41%) journals. Only 18% of the total number of EB members had affiliations related to radiology (n=286/1566). Forty journals (61%) did not report any indexing and database coverage. We found 26 journals (39%) which had a DOI number in its latest 5 articles. Fifty-nine (89%) journals clearly reported article processing change (APC) on the webpage. The median APC value was 641.43 USD (IQR, 300–918.75 USD; range, 100–2588 USD). Considering the latest 5 articles, the number of journals with radiologic images in all of the articles was 8 (12%). Mean peer-review time was 63.5 days (IQR, 21.75–87.5 days; range, 1–237 days) for the journals which indicated the submission and acceptance dates clearly.ConclusionWe demonstrated the several main characteristics of potential predatory journals in the radiology field such as reliability of the reported address, APC, publication frequencies, indexing features, features of published article and peer-review time which were all found to be similar to the characteristics of potential predatory journals in other biomedical fields

US-guided retrograde tibial artery puncture for recanalization of complex infrainguinal arterial occlusions

PURPOSEWe aimed to describe the technical aspects and outcomes of the retrograde tibial approach and balloon predilation for recanalization of complex infrainguinal arterial occlusions and determine the efficacy of this approach in minimizing failure rates. MATERIALS AND METHODSBetween September 2006 and April 2011, antegrade revascularization failed in 22 limbs with complex total occlusions within the infrainguinal arterial territory. For each of these antegrade failure cases in 22 patients, a retrograde tibial puncture had been attempted. Percutaneous recanalization and predilation were initially performed through tibial access, and final balloon dilatation or stent placement was performed from antegrade femoral access. The patients were followed up for functionality and wound healing. RESULTSAccess from the tibial artery was successfully obtained for all patients (100%). Successful recanalization was obtained in 18 patients (82%). Retrograde access was performed from the anterior tibial/dorsalis pedis artery in 12 patients and posterior tibial artery in 10 patients. One major and one minor complications were documented. CONCLUSIONRetrograde tibial recanalization technique in the infrainguinal complex arterial occlusion safely increases the success rates of percutaneous recanalization in the failed traditional approach and is a feasible endovascular option to avoid more invasive, time-consuming, and high-risk procedures

Investigation of Science Textbooks in terms of Science Process Skills

The aim of this study was to investigate the extent to which science process skills are represented in the texts and activities in the 3rd, 4th, 5th, 6th, 7th, and 8th grade science textbooks according to the learning areas in the science curriculum. This study was carried out by document analysis method. Course contents and activities in science textbooks were analyzed using descriptive analysis. Results showed that total of 899 science process skills are identified in the 3rd, 4th, 5th, 6th, 7th, and 8th grade science textbooks covering total 42 units. In addition, when the averages of science process skills use in science textbooks are examined, it has been determined that the use of science process skills in 6th (%23.9) and 7th (%18.8) grade textbooks is above the average. While the use of science process skills in science textbooks increases from the 3rd grade to the 4th grade at primary education level, the similar increase is not determined in the use of science process skills in secondary education science textbooks. Moreover, it is found that science process skills are mostly focused on the 6th grade science textbook (n=215) and the least in the 3rd grade science textbook (n=112). As a result, when science textbooks are evaluated according to grade levels in terms of science process skills, it is determined that the most common science process skill identified is observing, and the least used one is the using data and modelling

Research and application of the combination of ceramic and glass

Seramik, tarihi boyunca insanoğlunun ihtiyaçlarına karşılık verebilecek uygulamalarda kullanılmıştır. Yeni ihtiyaçlar yeni seramik çeşitlerini doğurmuş, bu yeni seramik çeşitlerinde sağlamlık ve estetik arayışı alternatif malzemelerin kullanımına teşvik etmiştir. 21. yy'a kadar süregelen bu yaşantısında, sanatçılar ana malzemeleri olan seramiği farklı materyallerle destekleme uğraşına girmişlerdir. İşte tam da bu noktada birlikteliğin her aşamasında uyum sağlayacak bir materyal olan camı, en uygun biçimde en uygun şekillendirme yöntemleriyle çalışmalarına dahil etmişlerdir. Yapımına başlandığı yıldan günümüze kadar farklı kullanım alanlarında değerlendirilen seramik ve cam, sanat başta olmak üzere çeşitli alanlarda birlikte kullanılmaya ve geliştirilmeye başlanmıştır. Bu araştırma ve uygulama tezinde, seramik ve camın tarihi, özellikleri, uygulanışı ve birlikteliği konusunda hangi yöntemlerin kullanıldığı, bu yöntemleri kullanan sanatçılardan örnekler verilerek açıklanmaya çalışılmıştır. Daha önce kullanılmış teknikler yeniden denenmiş, yeni teknikler geliştirilerek yapılan deneyler doğrultusunda olumlu ve olumsuz sonuçlar karşılaştırılarak değerlendirilmiştir. Ceramics, are used in applications that could correspond to the needs of human beings throughout history. New requirements engendered new types of ceramics, ceramic types, this new aesthetic quest for stability and has encouraged the use of alternative materials. The ceramic artists who support to the pursuit have engaged with the mainmaterials continuing up to this life until the 21. century. The ceramics artist have incorporated the work of the most suitable methods of formingthe most appropriate manner the glass which synergy among relevant agencies at this point to ensure compliance at every stage of a material. The ceramics and glass which is considered from at the begining of using until the this time, have began to develop with a variety of areas mainly at art. This thesis research and practice have attempted to history of ceramics and glass, features, application and which methods are used in combination and explain by giving examples of artists using these methods. Re-tested techniques which is used previously in line with experiments in new techniques, developed and evaluated by comparing the positive and negative results