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Beyond Expectations: Safinamide’s Unprecedented Neuroprotective Impact on Acute Spinal Cord Injury
No full textBackground: Traumatic spinal cord injury (SCI) is the most common preventable cause of morbidity. Despite rapid advances in medicine, effective pharmacological treatment against SCI has not yet been confirmed. This study aimed to investigate the possible anti-inflammatory, antiapoptotic, and neuroprotective effects of safinamide after SCI in a rat model. Methods: A total of 40 male Wistar albino rats were randomly divided into four groups. Group 1 underwent only laminectomy. Group 2 underwent SCI after laminectomy. In group 3, SCI was performed after laminectomy, and immediately afterward, intraperitoneal physiological saline solution was administered. In group 4, SCI was performed after laminectomy, and 90 mg/kg of safinamide was given intraperitoneally immediately afterward. Moderate spinal cord damage was induced at the level of thoracic vertebra nine (T9). Neuromotor function tests were performed and levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-1 beta (IL-1β) were measured. In both serum and spinal cord tissue, immunohistochemistry and histopathology studies were also conducted. Results: TNF-α, IL-1β, and IL-6 levels were found to be significantly increased in group 2 and group 3. In group 4, these levels were statistically significantly decreased. Group 4 also exhibited significant improvement in neuromotor function tests compared to the other groups. Histopathologically, it was found that group 4 showed significantly reduced inflammation and apoptosis compared to the other groups. Conclusion: This study revealed that safinamide has neuroprotective effects against SCI due to its anti-inflammatory, antiapoptotic, and antioxidant activities. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany 2024. corrected publication 2024
Fotodedektör Uygulamaları için Maskesiz Lazer Litografi ile Desenlenen Çinko Oksit Heteroeklemlerin Geliştirilmesi
No full textSunulan tez çalışması, nanoyapılı heteroeklemlere odaklanarak foto algılamada yüksek hassasiyetli ve performanslı, çevre dostu ve farklı sistemlere uyarlanabilen çok işlevli minimal cihaz tasarım yaklaşımları ile fotodedektör (FD) uygulamalarının vizyonunu geliştirmeye dayanmaktadır. Yüksek FD performansı için seçilen malzemelerin yanı sıra nanomalzemelerin yüzey alanının genişletilmesi de önemlidir. Desenli nanoyapıların düzenli dizilimi sağlanarak desensizlere kıyasla ışık soğurması ve yük transferi performanslarının arttırılması yenilikçi FD üretiminde ilgi çeken bir yaklaşımdır. Bu yaklaşımla, tez çalışması temel olarak desen tasarımına göre ikiye ayrılmıştır. Başka bir deyişle, maskesiz lazer litografi ile oluşturulan daire ve örgü desenlerinde dikey olarak mükemmel hizalanmış çinko oksit (ZnO) nanoçubuk diziler (NÇD'ler) büyütülmüştür. Öncelikle sıvı-hal sistemler için farklı çaplara (D=20 µm, 2D=40 µm, 4D=80 µm) ve daireler arası farklı mesafelere (L=20 µm, L/2=10 µm) sahip desenlerde ZnO NÇD'leri üretilmiştir. Desen geometrisinin etkileri ve görünür bölgede ışık soğurucu özelliklerin iyileştirilmesi için indiyum sülfür (In2S3) ile oluşturulan heteroeklemlerin performansları fotoelektrokimyasal (FEK) FD'lerde incelenmiştir. Desensiz ZnO NÇD'leri In2S3 ile kaplanmasına rağmen D-L desenlilere kıyasla daha düşük fotoakımla sonuçlanmıştır. D-L tasarımlıda ise 20 paso (20P) sayılı In2S3'ün sprey pirolizinden sonra akım yoğunluğunun %224 arttığı görülmüştür. Dairelerin çapı D şeklinde düzenlendiğinde ve daireler arasındaki mesafe azaltıldığında (L/2), ZnO NÇD/In2S3-20P tasarımının fotoanot/elektrolit arayüzünde en yüksek yük transferini sağlayarak en iyi performansı göstermiştir. Daha sonra bu tasarım iyonik jel elektroliti kullanarak yarı-katı-hal sistemler için taşınabilir FEK FD şeklinde de üretilerek 367 nm-535 nm dalga boyu aralığında 400 nm'de en yüksek performansı göstermiştir. Çalışmanın örgü desenli tasarımlarında çizgilerin merkezleri arasındaki mesafenin (L) FEK FD performansı üzerindeki etkileri sıvı-hal sistemlerde incelenmiştir. ZnO NÇD/In2S3-20P heteroekleminde örgü desenli FEK FD cihazı (L=20 µm) daire desenliye (D-L/2) kıyasla daha yüksek performans sergilediği görülmüştür. Son olarak tez çalışmasında, örgü desenli ZnO NÇD ve anorganik halojenür perovskit (AHP) heteroeklemleri geliştirilmiştir. AHP olarak kurşun bazlı CsPbBr3-Cs2PbBr5 çift fazlı ve kurşunsuz Cs2AgBiBr6 çift perovskit kullanılmıştır. Jel elektrolitli yarı-katı-hal sistemler için performans sonuçlarına göre kurşunsuz halojenür perovskit, kurşunlu için alternatif bir malzeme olduğu sonucu çıkarılmıştır. Özellikle açık devre potansiyeli (VOC) karşılaştırıldığında kurşunsuz FEK FD'nin, kurşunluya göre yaklaşık 5 kat daha yüksek olduğu ve görünür bölgede daha yüksek dalga boyundaki ışığa tepki verdiği saptanmıştır. Ayrıca tepki süreleri, In2S3 kaplamalı FEK FD'ye göre çok daha hızlı olduğu doğrulanmıştır. Katı-hal sistemlerde örgü desenli ZnO NÇD üzerine Cs2AgBiBr6 kaplanarak, maksimum fotoakım değerinin, +5 V ve AM 1,5 aydınlatma altında, sadece ZnO NÇD'lerine kıyasla yaklaşık 13,65 kat arttığı görülmüşür. +5 V ve 367 nm-522 nm dalga boyu aralığında 382 nm'de ise en yüksek FD performansları elde edilmiştir. Bu koşullarda, kurşunsuza kıyasla yaklaşık 2,5 kat daha yüksek fotoakıma ulaşmıştır. Bu tez çalışmasıyla desen şekli, geometrisi, farklı elektrolitlerin etkisi ve aktif alanların bir arada incelenmesi, kompakt cihaz mimarisinin kendi kendine güç sağlayan FEK FD uygulamaları için umut verici olması, kurşunsuz perovskitin alternatif malzeme olarak belirlenmesi ve milisaniye düzeyinde tepki sürelerine sahip kararlı ve çevre dostu FD'ler elde edilmesi, inovatif bir yaklaşımla literatüre kazanımı ve gelecekteki yeni nesil FD'ler için verimli ışık yönetim mekanizmasına yönelik güçlü bir strateji ortaya koymuştur. Anahtar Kelimeler: ZnO, In2S3, AHP, Maskesiz Lazer Litografi, FotodedektörThe presented thesis study is based on developing the vision of photodetector (PD) applications with high sensitivity and performance, environmentally friendly and multifunctional minimal device design approaches that can be adapted to different systems by focusing on nanostructured heterojunctions. In addition to, the materials selected for high PD performance, expanding the surface area of nanomaterials is also important. Providing regular alignment of patterned nanostructures, strong light absorption, and charge transfer acceleration compared to no patterned nanostructures is an interesting approach to PD performance. With this approach, the thesis study is divided into two sections according to the pattern design. In other words, ZnO NRAs that are perfectly aligned vertically were grown in the circle patterns and the mesh patterns using maskless laser lithography. Firstly, ZnO NRAs were grown in circular patterns having different diameters (D=20 µm, 2D=40 µm, 4D=80 µm) and different distances between circles (L=20 µm, L/2=10 µm) for liquid-state systems. The effects of pattern geometry and the performance of heterojunctions formed with indium sulfide (In2S3) to improve the light-absorbing properties in the visible region were investigated in photoelectrochemical (PEC) PDs. Although the no patterned ZnO NRAs were coated with In2S3, no patterned ZnO NRAs exhibited lower photocurrent density than D-L patterned structures. It was observed that the current density increased by 224% in the D-L design after the spray pyrolysis of 20 passes (20P) of In2S3. ZnO NRAs/In2S3-20P design showed the best performance by providing the highest charge transfer at the photoanode/electrolyte interface when the diameter of circles is D in pattern and the distance between the circles is decreased (L/2). After that, this design was also produced as a portable PEC PD for quasi-solid-state systems using ionic gel electrolyte and showed the highest performance at 400 nm in the between 367 nm to 535 nm wavelengths. The effects of the distance between the centers of the lines (L) in the mesh pattern on the PEC PD performance device performance were investigated in the liquid-state systems. The mesh patterned PEC PD device (L=20 µm) exhibited higher performance compared to the circle patterned (D-L/2) in the ZnO NRAs/In2S3-20P heterojunction. Finally, mesh-patterned ZnO NRAs and inorganic halide perovskite (IHP) heterojunctions were developed in the thesis study. Lead-based CsPbBr3-Cs2PbBr5 dual phase and lead-free Cs2AgBiBr6 double perovskite were used as IHP. According to the performance results for the quasi-solid-state system with gel electrolyte, it was concluded that lead-free halide perovskite is an alternative material for PDs. Especially, the open circuit potential (VOC) of mesh patterned lead-free PEC PD was obtained about 5 times higher than lead-containing perovskite. The light response of lead-free PEC PD extended through more visible regions compared to the lead-containing perovskite. In addition, it was confirmed that the response times were much faster than In2S3-coated PEC PD. In solid-state systems, by coating Cs2AgBiBr6 on mesh patterned ZnO NRAs, it was observed that the maximum photocurrent value increased about 13.65 times compared to pristine ZnO NRAs under +5 V and AM 1.5 illumination. The highest FD performances were obtained at 382 nm and +5 V in the between 367 nm and 522 nm wavelengths. Under these conditions, approximately 2.5 times higher photocurrent was achieved compared to lead-free. In this thesis study, the pattern shape, geometry, the effect of different electrolytes and active areas were examined together, the compact device architecture is promising for self-powered PEC PD applications, the determination of lead-free perovskite as an alternative material and the obtaining of stable and environmentally friendly PDs with millisecond response times have brought an innovative approach to the literature and a strong strategy for efficient light management mechanism for future new generation PDs. Keywords: ZnO, In2S3, IHP, Maskless Laser Lithography, Photodetecto
Yapay Zekânın Görsel İletişim Tasarımı Alanına Yansımaları
No full textYapay zekâ, günlük yaşantımızda yer aldığı gibi görsel iletişim tasarımı alanında da bulunmaya ve daha sık kullanılmaya başlanmıştır. Bu araştırmada yapay zekâ ve görsel iletişim tasarımı alanındaki etkileşim farklı boyutlarda incelenecektir. Tasarımcı ve yapay zekâ ilişkisi, yapay zekâ tarafından üretilen tasarımların tasarıma özgü kriterlere göre gösterdiği performans, eğitim alanında kullanımı gibi görsel iletişim tasarımını günümüzde kullanımı ve gelecekte oluşabilecek potansiyeli ortaya koymak amaçlanmaktadır. Anket çalışması ve derinlemesine görüşmelerle yapay zekâ hakkında ne kadar bilgi sahibi olunduğu, yapay zekâ kullanımının olumlu ve olumsuz yönleri ve gelecekte karşılaşabilecek durumlara yönelik ayrıntılı bir analiz çalışması gerçekleştirilmiştir. Elde edilen veriler bulgular bölümünde yorumlanmış ve sonuç bölümünde yapay zekânın görsel iletişim tasarımı alanına yansımaları ortaya konulmuştur.Artificial intelligence has started to be found and used more frequently in the field of visual communication design as well as in our daily lives. In this research, the interaction between artificial intelligence and visual communication design will be analysed in different dimensions. It is aimed to reveal the relationship between designer and artificial intelligence, the performance of designs produced by artificial intelligence according to design-specific criteria, the use of visual communication design today, such as its use in the field of education, and the potential that may occur in the future. A detailed analysis of how much information is known about artificial intelligence, the positive and negative aspects of the use of artificial intelligence and the situations that may be encountered in the future were analysed through questionnaires and in-depth interviews. The data obtained are interpreted in the findings section and the reflections of artificial intelligence on the field of visual communication design are presented in the conclusion section
DİGİTAL UYGULAMALARLA ZENGİNLEŞTİRİLMİŞ İNGİLİZCE ÖĞRETİMİNİN ÖĞRETMEN BİLİŞİ VE ÖĞRENCİ İNANIŞINA ETKİSİ
No full textBu çalışmada, dijital uygulamalarla zenginleştirilmiş İngilizce öğretiminin öğretmen bilişi ve öğrenci inanışı üzerine etkisi araştırılmıştır. Araştırmaya, özel bir okulun 35 farklı ildeki K12 düzeyinde görev yapan 49 İngilizce öğretmeni ve bu öğretmenlerin 214 öğrencisi katılmıştır. Bu çeşitlilik ile örneklemin temsil gücünün arttırılması hedeflenmiştir. Öğretmen bilişi ve öğrenci inanışını tespit etmek amacıyla öğretmen ve öğrencilere dijital uygulamalarla zenginleştirilmiş İngilizce öğretimine yönelik çevrimiçi bir anket uygulanmıştır. Dijital uygulamalarla zenginleştirilmiş İngilizce öğretimine yönelik hizmetiçi eğitimin ve öğretmenlerin öğrencilerine uyguladıkları sınıf içi uygulamaların ardından anket yeniden uygulanmıştır. Eğitim öncesinde ve sonrasında uygulanan anketler karşılaştırıldığında, dijital uygulamalarla zenginleştirilmiş İngilizce öğretimine yönelik hizmet içi eğitiminin, öğretmen bilişi ve öğrenci inanışı üzerinde olumlu etkisi olduğu ortaya çıkmıştır. Ayrıca, öğretmen ve öğrenci anket sonuçlarında görülen paralel yükseliş, yabancı dil sınıflarında öğretmen bilişinin döngüsel bir şekilde sınıf uygulamalarına ve öğrenci inanışına olan etkisini vurgulamıştır. Bu çalışma, hem K-12 düzeyinde dijital uygulamalarla zenginleştirilmiş İngilizce öğretiminin öğretmen bilişi ve öğrenci inanışı üzerine etkilerini incelemesi hem de, öğretmen, öğrenci ve gözetmen olmak üzere, üç farklı bakış açısından beslenen üçleme yöntemiyle gözlem olanağı sağlaması nedeniyle İngiliz dili eğitimi (ELT) alanına bir katkı niteliğindedir
Language/Cognitive and Social/Self-care Development of Preschool Children Under the Care of Social Services
No full textLack of stimulation and absence of one-to-one interaction with an adult constitute risks for children's development under the care of social services. According to differential susceptibility theory, children can be differently affected by their environments due to their individual characteristics. The current study compared the developmental difference/delay of children living in different care types (institution, care village, group home, foster care) and never-institutionalized children from low-SES families regarding language-cognitive and social/self-care skills. Also, children's temperament was investigated as a moderator in the relationship between care types and children's developmental levels. Therefore, 357 children aged between 2-5 years and their caregivers/mothers participated in the study. Developmental levels of children were assessed via Ankara Developmental Screening Inventory. The results revealed that children in institutions had higher developmental difference scores than those in foster care and low-SES family in language-cognitive skills. Children in care villages and group homes had higher developmental difference scores than those in low-SES families. In social/self-care skills, children in institutions, care villages, and group homes had higher developmental difference scores than those in foster care and low-SES families. Besides, the moderator role of children's temperament was significant in several associations. The results were interpreted considering future intervention programs and social policies
Early Retirement Incentives and Transition Into Informality
No full textThis paper explores the impact of a super early retirement incentive that allowed men to retire as early as 44 years old in Turkey in 1992. Relying on a Fuzzy Regression Discontinuity Design, I find that taking up the incentives significantly reduced the labor force participation of middle-aged men in Turkey. Analysis by education categories suggests that the incentives had an impact on both the skilled and unskilled labor force. I find that the policy-induced take-up of pension benefit receipt significantly increased the probability of moving into informal employment contracts. Findings suggest that the probability of informal wage employment increased for low-skilled individuals while the probability of informal self-employment probability increased for high-skilled individuals. Among low-skilled workers, the incentives seem to have relaxed credit constraints. © 2024 Elsevier B.V
Endothelial Dysfunction in Prediabetes and Diabetes Mellitus in Patients With Normal Coronary Arteries
No full textBackgroundDiabetes mellitus (DM) is a global health issue associated with increased cardiovascular disease risk. Endothelial dysfunction is a known precursor to atherosclerosis and cardiovascular disease, and its role in the pathogenesis of DM complications is well-documented. There is limited information in the evaluation of endothelial function in prediabetic patients using flow-mediated dilation (FMD), and studies have not excluded patients with known atherosclerosis or coronary artery disease. Thus, in this study, we aimed to evaluate the endothelial functions using FMD from the brachial artery of DM and prediabetes patients who had normal coronary arteries.MethodsThis study included 73 participants: 25 with DM, 25 with prediabetes, and 23 normoglycemic controls, all with normal coronary arteries on angiography. FMD measurements were conducted following established protocols, and statistical analysis was performed using standard methods to compare FMD levels among groups.ResultsThe groups were comparable in clinical and demographic characteristics, except for fasting plasma glucose levels. Significant differences in FMD levels were observed: 10.1% in the DM group, 16.5% in the prediabetes group, and 14.8% in the control group (P = 0.004). Diabetic patients had significantly lower FMD levels than both prediabetic and normoglycemic individuals. No significant difference in FMD was found between prediabetic and control groups.ConclusionsDiabetic patients exhibited significant endothelial dysfunction compared to normoglycemic individuals, while prediabetic patients did not show similar dysfunction. These findings suggest a window of opportunity in the prediabetic stage for early intervention to prevent advanced endothelial dysfunction.Trial registration numberISRCTN Registry ISRCTN15351014. Registry date: 23/09/2024. Retrospectively registered
An Ethical Analysis of a Prospective New Paradigm of Life: Nanotechnology-Enabled Human Beings Within the Framework of Principlism
No full textNanotechnology (NT)-enabled disease-free life is a form of reconstruction of the human body that promises a paradigm shift toward a new form of human existence in an imaginable life. However, as human reconstruction may be within the limits of the concept of “human enhancement,” it is not clear to what extent “enhanced humans” will be ethically acceptable or desired. This study discusses the ethical implications of NT-embedded enhanced humans and this new imaginable life. First, ethical concerns arising from the existence of a grey zone of certain dilemmas regarding benefits and possible/unpredicted risks are addressed in terms of the four main principles of bioethics. Then, we focus on the ethical problems in human nano-enhancement. Finally, we study the methods of analyzing these ethical problems within the framework of principlism to conceive a comprehensive and coherent bioethical understanding. © 2023 John Wiley ; Sons Ltd
Turkish Society of Gastroenterology: Pancreas Working Group, Acute Pancreatitis Committee Consensus Report
No full textAcute pancreatitis (AP) is a clinical condition that arises acutely in the pancreas through various inflammatory pathways due to multiple causes. Turkish Society of Gastroenterology Pancreas Working Group developed comprehensive guidance statements regarding the management of AP that include its epidemiology, etiology, clinical presentation, diagnostic criteria, disease severity, treatment, prognosis, local and systemic complications. The statements were developed through literature review, deliberation, and consensus opinion. These statements were ultimately used to develop a conceptual framework for the multidisciplinary management of AP