656 research outputs found

    Doubly warped products

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    AbstractIn this paper we study geodesic completeness of Riemannian doubly warped products and Lorentzian doubly warped products. We give necessary conditions for generalized Robertson–Walker space-times with doubly warped product spacial parts to be globally hyperbolic. We also state some results about Killing and conformal vector fields of doubly warped products

    Social Studies Preservice Teachers’ Views on and Experiences with WebQuest

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    The current study aims to determine prospective teachers’ opinions about WebQuest applications by both introducing them to the WebQuest teaching materials and obtaining their experiences in the WebQuest design process. This study employs phenomenology as a qualitative research approach. The study was conducted in the spring semester of the 2017-2018 academic year with the third year undergraduate students in the social studies education department of a state university in Ankara. Two different data collection tools, a Peer Evaluation Form and an Interview Form, were used. Content analysis was used to analyze the data obtained. According to the findings of the study, social studies preservice teachers think that teacher supervision of Webquest teaching activities is advantageous. Preservice teachers defined the specific principles of WebQuest teaching activities as a weak factor. Additionally, preservice teachers emphasized that WebQuest teaching activities are difficult to implement in environments where Internet and computer facilities are not available. Even though almost half of the participants stated that they wanted to include WebQuest teaching activities in their classes when they started the teaching profession, they expressed about their concerns

    The Effect of Acute Aerobical Exercise on Arterial Blood Oxygen Saturation of Athletes

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    The aim of this study was to investigate the effect of acute aerobic exercise on arterial blood hemoglobin oxygen saturation in athletes.36 healthy male athletes participated voluntarily with the age (20.9 ± 1.6 yrs), weight (69.8 ± 5.5 kg) and height (169.6 ± 3.7 cm), who studied at school of physical education and practiced 90 minutes of exercise 6 days a week,. This study was conducted with the approval of Ethics Committee of Health Sciences Institute with session date specified in article of Ethics Committee, dated in 13.09.2017.The heights, body weights and VO2 max values of participants were determined by VO2 max shuttle run test once, pre- and post-shuttle run heart rates and oxygen saturations were determined by pulse oximetry. The statistical analysis of data was made in SPSS 21.0 for windows package program. The normality test of data was done by Kolmogorov-Smirnov test, and it was found that data was not normally distributed. The Wilcoxon test, a nonparametric test, was used to determine for difference between pre-test and post-test. The significance value was taken at level 0.01.As a result of statistical analyses, it was determined that there was a statistically significant difference between oxygen saturations and heart rates of participants before and after exercise. In conclusion, it can be said that acute aerobic exercise can reduce oxygen saturation

    AccessIT Projesi ve Dijitalleştirme Uzaktan Eğitim Programının Değerlendirilmesi

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    AccessIT is an EU-funded project under EU’s Education and Culture Program aiming to digitize a certain amount of sources that are part of the cultural heritage, to transfer them to Europeana, and to sustain the education infrastructure to achieve this goal in the partner countries of Greece, Poland, Serbia, Turkey and UK. In this study, in addition to the general evaluation of the AccessIT Project, it is aimed to investigate the awareness of participants in thefield on digitization and digital content management, their self-efficiency perceptions, and to evaluate the education program based on the data acquired from the survey of544participants who were enrolled in the distance education program offered within the scope of the project.It was found out in the study that the AccessIT Project has had an important function in Turkey and the distance education program significantly contributed to participants ’ self-efficiency perceptions about digitization.AccessIT, Avrupa Birliği (AB) Eğitim ve Kültür Programı altında kabul edilen İngiltere, Polonya, Sırbistan, Türkiye ve Yunanistan’ın yer aldığı, belirli miktar­daki kaynağın dijitalleştirilerek Europeana’ya aktarılmasını ve bunun için gerekli eğitim alt yapısının sağlanmasını hedefleyen bir projedir. Bu çalışmada, AccessIT Projesinin genel bir değerlendirmesinin yanı sıra, proje kapsamında verilen uzak­tan eğitim programına devam eden 544 katılımcı üzerinde gerçekleştirilen anket çalışmasının verilerine dayanarak, Türkiye’de ilgili alandaki katılımcıların diji- talleştirme ve dijital içerik yönetimi konularındaki farkındalıklarının, kuramsal ve uygulamaya yönelik yeterlilik algılarının ve eğitim programının irdelenmesi amaçlanmıştır. Çalışmada, AcessIT Projesinin Türkiye açısından önemli bir işlev gördüğü ve proje kapsamında gerçekleştirilen uzaktan eğitim programının katı­lımcıların dijitalleştirme konusundaki yeterlilik algılarına ciddi düzeyde katkıda bulunduğu anlaşılmıştır

    Paraoxonase and Arylesterase Activities, Lipid Profile, and Oxidative Damage in Experimental Ischemic Colitis Model

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    Objective. In the present study, since PON1 is known as an HDL-associated antioxidant enzyme that inhibits the oxidative modification of LDL and oxidative stress plays a role in the pathogenesis of mesenteric ischemia, we investigated the changes in PON1 activity and lipid profile in an experimental ischemic colitis model. Methods. Forty male Wistar albino rats were divided into two groups: the control group (N = 15) and the experimental group (N = 25). All animals were anesthetized with ether and ketamine anesthesia to undergo a midline laparotomy. Ischemic colitis was induced by marginal vessel ligation in the splenic flexura (devascularization process). A sham laparotomy was performed in the control group. All animals were sacrificed on the seventh postoperative day. Oxidative stress marker (malonyldialdehyde, MDA), lipid profile, and paraoxonase (PON-1) and arylesterase activities were determined. Histopathological evaluation was done under light microscopy, after sectioning and staining with hematoxyline and eosin. Statistical analysis was conducted using Student's t-test and Mann-Whitney U test, and P 0.05).Conclusions. PON1 and arylesterase play an important role in the pathophysiology of ischemic colitis

    Curvature of Multiply Warped Products

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    In this paper, we study Ricci-flat and Einstein Lorentzian multiply warped products. We also consider the case of having constant scalar curvatures for this class of warped products. Finally, after we introduce a new class of spacetimes called as generalized Kasner space-times, we apply our results to this kind of space-times as well as other relativistic space-times, i.e., Reissner-Nordstrom, Kasner space-times, Banados-Teitelboim-Zanelli and de Sitter Black hole solutions.Comment: 28 pages, corrected typos, to appear in Journal of Geometry and Physic

    Hepatoprotective effects of B-1,3-(D)-Glucan on bortezomib-induced liver damage in rats

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    The aim of this study was to evaluate the effects of beta -1,3-(D)-glucan as an antioxidant and tissue protective agent and study the biochemical, histopathologic, and immunohistochemical effects of first therapeutic proteasome inhibitor bortezomib on the liver for treating relapsed multiple myeloma. The experiment included 36 adult male rats, which were divided into four treatment groups: control (healthy); bortezomib-treated; beta-1,3-D-glucan-treated; and bortezomib + beta-1,3-(D)-glucan-treated. Each group was subdivided into two subgroups based on time of sacrifice (48 or 72 h). After the experiments, superoxide dismutase (SOD) activity and lipid peroxidation (LPO) amounts were determined, and immunohistochemical and histopathological changes were examined in all rat liver tissues. beta -1,3-(D)-Glucan treatment normalized changes of LPO and stimulated an over activity of endogenous SOD. The results of the histopathologic parameters showed that treatment with beta -1,3-(D)-Glucan in the bortezomib group ameliorated the development of non-specific reactive hepatitis (NSRH) and Kupffer cell activation via NF-kB. Administration of beta -1,3-(D)-Glucan is effective in reversing tissue damage induced by bortezomib in rat livers.Bu çalışmanın amacı, relaps multiple miyelom tedavi etmek için kullanılan ilk terapötik proteazom inhibitörü olan bortezomibin karaciğer üzerine immunohistokimyasal, histopatolojik ve biyokimyasal etkilerini araştırmak ve bir antioksidant ve doku koruyucu ajan olarak B-1,3-(D)-glukanın etkilerini değerlendirmekdi. Deney; kontrol (sağlıklı), bortezomib ile tedavi, B-1,3-(D)-glukan ile tedavi ve bortezomib + B-1,3-(D)-glukan ile tedavi olmak üzere dört tedavi grubuna bölünen 36 yetişkin erkek sıçan içerdi. Her bir grup sakrifikasyon zamanına (48 veya 72 saat) göre iki alt gruba ayrıldı. Deneylerin bitiminden sonra, süperoksit dismutaz (SOD) aktivitesi ve lipid peroksidasyon (LPO) miktarları ölçüldü ve tüm sıçan karaciğer dokularında immünohistokimyasal ve histopatolojik değişiklikler incelendi. B-1,3-(D)-glukan ile tedavi LPO değişikliğini normalize etti ve endojen SOD aktivitesi aşırı uyardı. Histopatolojik parametrelerin sonuçları, bortezomib grubunda B-1,3-(D)-glukan ile tedavi NF-kB yoluyla Kupffer hücre aktivasyonunu ve non-spesifik reaktif hepatit (NSRH) gelişimini regüle ettiğini gösterdi. B-1,3-(D)-glukan uygulaması, sıçan karaciğerinde bortezomibin neden olduğu geri döndürülebilir doku hasarında efektifdir

    PERIPHERAL BLOOD STEM CELL TRANSPLANTATION FOR LYMPHOMA PATIENTS: SINGLE CENTER EXPERIENCE

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    Amaç: Birinci sıra tedaviye yeterli yanıt vermeyen yada relaps olan Hodgkin ve Non-Hodgkin lenfomalı hastalarda ikinci sıra tedavi sonrası otolog periferik kök hücre(OKIT) destekli yüksek doz kemoterapi yaygın olarak kullanılmaktadır. Biz buçalışmada Dokuz Eylül Üniversitesi Tıp Fakültesi Hematoloji Bilim dalı tarafından2005-2009 yılları arasında izlenen ve periferik kök hücre nakli yapılan 45 lenfomahastasını sunmayı amaçladık.Gereç ve yöntemler: Hastaların yaşları 19-67 arasında ve yaş ortalamaları 38,87 idi.Tanılarına bakıldığında %24,4'ü Diffüz Büyük B hücreli NHL, %35,6'sı NodülerSklerozan Hodgkin Lenfoma, %17,8'i miks sellüler Hodgkin lenfoma, %8,9'u lenfoblastiklenfoma idi.Bulgular: Hastaların %90'ına OKIT destekli yüksek doz tedavi, %10'una ise allogeneikkök hücre nakli uygulandı. Nakil sonrası hastaların son yapılan değerlendirmelerinde45 hastanın 13'ünün komplet remisyonda, 2'sinin progresif hastalık, 2'sinin parsiyelyanıtlı, 3'ünün stabil hastalık olduğu görüldü. 12 hasta hastalık ilişkili, 2'si hastalık dışınedenlerle ve 11 hastada sepsis nedeni ile kaybedildi.Sonuç: Otolog periferik kök hücre destekli yüksek doz tedavi ile özellikle platin bazlıtedaviye yanıt veren lenfoma hasta gurubunda yüz güldürücü sonuçlar alınmaktadır.Objective: Peripheral Blood Stem Cell Transplantation (PBSCT) following intensiveconditioning chemotherapy has improved the survival in relapsed Hodgkin's disease(HD) and non- Hodgkin's lymphoma (NHL). In this study we aim to present 45relapsed refractory lymphoma patients who had peripheral blood stem celltransplantation and were observed between 2005 and 2009 by Dokuz Eylül UniversityFaculty of Medicine Hematology Department.Material and methods: The age range of 45 pateients that were included in this studywas between 19 and 67, and the mean age is 38,87... When we look at subtypes, 24.4%diffuse large B-cell NHL, 35.6% Nodular Sclerozan Hodgkin\\\'s Lymphoma, 17.8% mixed cellula rity Hodgkin\\\'s lymphoma, and 8.9% were diagnosed as lymphoblastic lymphoma.Results: 90% of the patients were treated with high-dose chemotherapy withautologous PBSCT, to the 10% of the pateients allogeneic PBSCT from full matchedrelatives was applied.. Recent evaluation of 45 patients, 13 patients were CR (28.9%), 2have progressive disease, 2 PR, 3 were classified as SD. Associated with the disease in12 patients, 2 of them for reasons other than illness, and 11 patients had died of sepsis.Conclusion: PBSCT following intensive conditioning chemotherapy has improved thesurvival in relapsed-refractory lymphoma patients
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