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Article Citation - WoS: 4Citation - Scopus: 5Construction of a Complex Jacobi Matrix From Two-Spectra(Hacettepe Univ, Fac Sci, 2011) Guseinov, Gusein Sh; MathematicsIn this paper we study the inverse spectral problem for two-spectra of finite order complex Jacobi matrices (tri-diagonal matrices). The problem is to reconstruct the matrix using two sets of eigenvalues, one for the original Jacobi matrix and one for the matrix obtained by deleting the first column and the first row of the Jacobi matrix. An explicit procedure of reconstruction of the matrix from the two-spectra is given.Article Citation - Scopus: 3Protective Effects of Metformin in Non-Diabetic Rats With Experimentally Induced Lower Extremity Ischemia-Reperfusion Injury(Turkish National Vascular and Endovascular Surgery Society, 2025) Küçük, Ayşegül; Dursun, Alı Dogan; Arslan, Mustafa; Sezen, Şaban Cem; Yıldırım, Alperen Kutay; Özer, Abdullah; Demirtas, HuseyinAim: Lower extremity ischemia-reperfusion (IR) injury can lead to substantial skeletal muscle damage and systemic complications, primarily driven by oxidative stress and inflammation. In addition to its well-known glucose-lowering effects, metformin possesses antioxidant and anti-inflammatory properties that may confer protection against tissue damage caused by IR. This study aims to evaluate the potential protective effects of metformin on skeletal muscle injury using a rat model of lower extremity IR.Material and Methods: A total of twenty-four male Wistar albino rats were randomly divided into four experimental groups: Control (C), Ischemia-Reperfusion (IR), IR with metformin at 4 mg/kg (IR+M4), and IR with metformin at 8 mg/kg (IR+M8). Ischemia was induced by clamping the infrarenal aorta for 45 minutes, followed by a reperfusion period of 120 minutes. In the treatment groups, metformin was administered intraperitoneally at the onset of ischemia. Gastrocnemius muscle tissues were harvested for subsequent histopathological and biochemical evaluations, including measurements of Total Antioxidant Status (TAS), Total Oxidant Status (TOS), and Oxidative Stress Index (OSI).Results: Histopathological analysis demonstrated a significant reduction in muscle atrophy, degeneration, leukocyte infiltration, and fiber fragmentation in the IR+M8 group compared to the IR group. Biochemical assessments showed that TAS levels were considerably elevated, whereas TOS and OSI levels were markedly reduced in the metformin-treated groups, with the most prominent effects observed at the higher dosage of 8 mg/kg.Conclusion: The findings indicate that metformin exerts a dose-dependent protective effect against skeletal muscle injury resulting from lower extremity ischemia-reperfusion in rats. These protective properties are likely due to metformin’s antioxidant and anti-inflammatory mechanisms, highlighting its potential therapeutic value in mitigating IR-induced tissue damage.Article Effects of Topological Structure of Project Network on Computational Cost(Golden Light Publ, 2024) Aminbakhsh, SamanUnderstanding how network complexity affects optimization algorithms is crucial for improving computational efficiency. This study investigates how variations in network complexity impact the performance of optimization algorithms. By examining networks with different serial/parallel indicator (I2) values, the research uncovers several key insights into how topology influences computational requirements. The experiments show that higher I2 values, which are closer to serial configurations, heighten the problem's complexity. This study reveals that networks with lower I2 values, which exhibit steeper time-cost curves with fewer solutions over their efficient frontiers, require significantly more CPU time, indicating that project complexity does not necessarily scale with the extend of the Pareto fronts. This contradicts the expectation that more Pareto front solutions would inherently demand greater computational resources. Lastly, the study highlights that while the number of time-cost realizations is often used to gauge project complexity, it may not be conclusive on its own and that one complexity measure can outperform another. Although it can be an effective indicator, it does not fully capture the computational challenges posed by different network topologies. This study further acknowledges the difficulty in establishing a clear link between project performance and complexity due to the multifaceted nature of the problem. The findings suggest that exploring similar problems in other contexts could provide valuable insights into understanding and managing computational complexity.Article Citation - WoS: 11Citation - Scopus: 16Biomaterials and Tissue Engineering for Regenerative Repair of Articular Cartilage Defects(Turkish League Against Rheumatism, 2009) Tur, Kazim; Department of Metallurgical and Materials EngineeringArticular cartilage defects heal very poorly and lead to degenerative arthritis. Existing medications cannot promote healing process; cartilage defects eventually require surgical replacements with autografts. As there is not enough source of articular cartilage that can be donated for autografting, materials that promote cartilage regeneration are important in both research and clinical applications. Tissue engineering involves cell growth on biomaterial scaffolds in vitro. These cells are then injected into cartilage defects for biological in vivo regeneration of the cartilage tissue. This review aims first to provide a brief introduction to the types of materials in medicine (biomaterials), to their roles in treatment of diseases, and to design factors and general requirements of biomaterials. Then, it attempts to sum up the recent advances in engineering articular cartilage; one of the most challenging area of study in biomaterials based tissue engineering, as an example to the research on regenerative solutions to musculoskeletal problems with an emphasis on the biomaterials that have been developed as scaffolds for cartilage tissue engineering. The definitive goal on cartilage regeneration is to develop a system using biomimetic approach to produce cartilage tissue that mimics native tissue properties, provides rapid restoration of tissue function, and is clinically translatable. This is obviously an ambitious goal; however, significant progress have been made in recent years; and further advances in materials design and technology will pave the way for creating significantly custom-made cellular environment for cartilage regeneration. (Turk J Rheumatol 2009; 24: 206-17)Article Citation - WoS: 16Citation - Scopus: 20Common Fixed Point Theorems in Cone Banach Spaces(Hacettepe Univ, Fac Sci, 2011) Abdeljawad, Thabet; Karapinar, Erdal; Tas, Kenan; MathematicsRecently, E. Karapinar (Fixed Point Theorems in Cone Banach Spaces, Fixed Point Theory Applications, Article ID 609281, 9 pages, 2009) presented some fixed point theorems for self-mappings satisfying certain contraction principles on a cone Banach space. Here we will give some generalizations of this theorem.Article Tests of Rationality in the Turkish Foreign Exchange Market(Central Bank Republic Turkey, 2014) Topbas, Neslihan; International Trade and LogisticsThe rationality of expectations has been tested in many foreign exchange markets using survey data. This study is aimed at gaining empirical insights about the expectations of market participants in the Turkish foreign exchange market. Using survey data provided by Central Bank of Turkey on the exchange rate of the Turkish lira against the US dollar, it is determined that the mean of expectations of market participants for one year and one month ahead were higher than the mean of actual depreciation. The analysis resulted in rejection of the popular test for forward exchange rate unbiasedness in predicting the future spot exchange rate. Another test of rationality has also been checked and the result has been rejection as well, which can be interpreted that the forward premium contains additional information for exchange rate forecasts.Article Creative Pattern Trials for Above the Keyboard Wear With Trompe L'oeil Illusion(Anadolu Univ, 2022) Aydeniz, Sena Surmeli; Cegindir, Nese YasarThe design scenario of this study is based on seeking answers to the question "How can we produce different, extraordinary and original shirts for working women with the Trompe l'oeil (illusion) technique?". The sample of the study, in which the user-oriented design research method was used, is women working above the keyboard. Within the scope of the study, three women's shirts were produced with creative pattern applications. The classical techniques known in garment production have been reconstructed with the Trompe l'oeil technique. The findings were discussed in two dimensions as the process carried out for these three shirts and the prototype evaluation. Osborn's checklist was used to create the design value of the shirts. For the evaluations of the marketability of the products, measurement was made in the form of voting over Google Forms. As a result of the voting, the first prototype was found to be more suitable for the target audience. Based on the individual comments received, it has been observed that originality varies when the position and needs of the target audience come into play. The importance of the user profile in creative product design has been understood.Article Citation - WoS: 3Continuity and Change in Turkish Foreign Policy Toward Africa(Hale Sivgin, 2008) Uchehara, Kieran E.This article aims to give an overview of Turkey's improving relations with African countries. It indicates that Turkey's international relations concentrate more on her relations with the European Union, Caucasians, Balkans, the Middle East and USA. Turkey's opening up to Africa today, is a new development in her international relations. However, such relations had existed during the times of the Ottoman empire, especially with north Africa. Turkish academics, universities and media have not yet grasped the importance of Africa in the academic sense and as such none of them has a center on African research. Likewise, the African academics, universities and media. Other than communications between Turkey and African countries and related institutions on the subject matter, it is not possible to talk about significant serious data on Turkey-Africa relations. The relations between Turkey and Africa were on each individual African country's basis. However, with the recent development in the world today known as "globalization", Turkey is trying to improve her political and economic relations with the entire African continent and with the recent development, we have seen that there are high level visits between Turkey and African conutries. Trade relations between Turkey and African countries are in progress.Article The Turkish Adaptation, Validity, and Reliability of the Fragmented Self Inventory(Association for Clinical Psychology Research, 2025) Türkarslan, Kutlu Kağan; Akın, Zeynep GülParçalanmış Kendilik Envanteri (PKE), Heinz Kohut'un tanımladığı parçalanmış kendilik deneyimlerini incelemek için geliştirilmiş bir öz-bildirim ölçüm aracıdır. Ölçek, psikanalitik kendilik psikolojisi bağlamında parçalanmış büyüklenmecilik (PKE-PB) ve parçalanmış idealleştirme (PKE-Pİ) olmak üzere iki kendilik eksenindeki deneyimlere odaklanmaktadır. Bu çalışmanın amacı PKE’yi Türkçe’ ye uyarlamak ve psikometrik özelliklerini Türkçe konuşan bir örneklemde değerlendirmektir. Çalışmanın verileri 495 katılımcıdan toplanmıştır (kadın = %67.88, Ort.yaş = 33.86, SS = 12.87). PKE'nin iki faktörlü yapısını doğrulamak için doğrulayıcı faktör analizi gerçekleştirilmiştir. Ölçeğin yakınsak geçerliği, PKE-PB ve PKE-Pİ puanlarının; özsaygı, patolojik narsisizm, öz-denetim, disiplin, duygu düzenleme güçlüğü, hayat anlam ve amacı, depresyon, anksiyete ve stres değişkenleri ile ilişkisine bakılarak değerlendirilmiştir. Ölçeğin güvenirliği ise iç tutarlılık katsayıları ve test-tekrar test sınıf içi korelasyonları ile incelenmiştir. Doğrulayıcı faktör analizinin sonuçları PKE'nin Türkçe formunun iki faktörlü yapısını desteklemektedir. Parçalanmış büyüklenmecilik ekseninde daha yüksek puanların, düşük benlik saygısı ve yüksek patolojik narsisizm belirtileri ile; parçalanmış idealleştirmede daha yüksek puanların ise düşük öz-denetim, düşük disiplin, yüksek duygu düzenleme zorlukları ve hayatta anlam ve amaç bulma-da daha fazla güçlük çekme ile ilişkili olması, PKE’nin yakınsak geçerliğini desteklemektedir. PKE-PB ve PKE-Pİ alt ölçeklerinin, tatmin edici iç tutarlılık gösterdiği (McDonald'ın ω = .77 ve .86) ve dört haftalık test-tekrar test güvenirliğine (SKK = .78 ve .81) sahip olduğu görülmüştür. Parçalanmış büyüklenmecilik ve parçalanmış idealleştirmenin depresyon, anksiyete ve stresi yordadığı yol analizinde, parçalanmış büyüklenmeciliğin anksiyete ve stresi, parçalanmış idealleştirmenin ise depresyon, anksiyete ve stresi anlamlı şekilde yordadığı bulunmuştur. Bu çalışmanın bulguları, PKE'nin Türkçe formunun parçalanmış büyüklenmecilik ve parçalanmış idealleştirme deneyimlerini ölçmekte kullanılabileceğine işaret etmektedir.Article Citation - Scopus: 9The Effects of Eryngium Campestre Extracts on Glutathione-S Glutathione Peroxidase and Catalase Enzyme Activities;(Turkish Pharmacists Association, 2014) Güneş,M.G.; İşgör,B.S.; İşgör,Y.G.; Shomali Moghaddam,N.; Geven,F.; Yildirim,Ö.Eryngium campestre L. (Apiaceae) are known in Turkish folk medicine as ‘Bogadikeni’ and wildly distributed in all parts of Turkey. Infusion of different parts of this species are well known as diuretic, appetizer and stimulant. In the present study, methanol extracts from flowers and leaves of E. campestre were evaluated for their potential medicinal value in terms of biological targets participate in antioxidant defense such as glutathione-S-transferase (GST), glutathione peroxidase (GPx) and catalase (CAT). Results obtained show that the methanol extract of flowers were found to have higher amount of phenolic and flavonoid contents than the leaves. The evaluation of extracts against biological target revealed that, the maximum GST enzymes inhibition activities was observed with methanol extract from flowers of E. campestre with IC50 value of 363 ng/mL. In this study, none of the extracts evaluated were shown any reasonable GPx and CAT inhibition. © 2014, Turkish Pharmacists Association. All rights reserved.
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