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Article Representations of Africa in Ben Okri's and Alexander Mccall Smith's Works(Ovidius University, 2023) Aksoy,N.B.This presentation explores the representation of Africa in different novels by two different writers. The novels belong to late 20th and early 21st-century British fiction set in Africa. The two writers have different backgrounds in many ways except for their engagement, love and complicated relationship with the African continent. I argue that the representation by these writers reveals the meaning and significance of Africa in a postcolonial context as a space of nostalgia, loss, and eventually, hope in contemporary British fiction. © 2023 Ovidius University. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 5Automorphisms of the mapping class group of a nonorientable surface(Springer, 2017) Atalan, Ferihe; Szepietowski, BlazejLet S be a nonorientable surface of genus g >= 5 with n >= 0 punctures, and Mod(S) its mapping class group. We define the complexity of S to be the maximum rank of a free abelian subgroup of Mod(S). Suppose that S-1 and S-2 are two such surfaces of the same complexity. We prove that every isomorphism Mod(S-1) -> Mod(S-2) is induced by a diffeomorphism S-1 -> S-2. This is an analogue of Ivanov's theorem on automorphisms of the mapping class groups of an orientable surface, and also an extension and improvement of the first author's previous result.Article Citation - Scopus: 5The Relationships Between Human Values, Absenteeism Attitudes and Reasons;(Hacettepe University, 2016) Demirutku,K.; Tekinay,S.The present study was conducted to investigate the relationships between human values, absenteeism attitudes, and absenteeism reasons. A correlation study was carried out with 180 students who were enrolled in different programs in a private university located in Ankara. Value orientations of the participants was measured by using Portrait Values Questionnaire (Schwartz et al., 2012) and absenteeism attitudes were measured by using semantic differential scales. In addition, students reported the frequencies of not going to the campus in class-days, and not attending the classes despite being in the campus with various reasons on the scales developed by referring to the relevant literature to be used in the present study. Correlation analyses revealed that the importance of hedonism and stimulation values was positively, whereas the importance of self-direction and conformity values was negatively correlated with absenteeism attitudes and reasons. It was proposed that absenteeism attitudes and reasons might have the function of expressing different values. The results were discussed by taking into account the measurement- and sample-related limitations of the study, and corresponding suggestions for future research were presented. © 2016, Hacettepe University. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Kardiyovasküler Aldatma-Salgını: Kardiyovasküler Tedavilerde Kandırma ve Yanlış Bilgilendirme Epidemisinin Yaygınlaşması(Baycınar Medical Publishing - Baycınar Tıbbi Yayıncılık, 2024) Demirkılıç, Ufuk; Tosun, BurcuSon zamanlarda, bazı kalp damar cerrahları sıklıkla yanıltıcı terimler kullanarak pazarlama amacıyla sosyal medyayı giderek daha fazla kullanmaktadır. “Kardiyovasküler aldatma- salgını” olarak adlandırdığımız bu eğilim, kardiyovasküler tedaviler için yanıltıcı reklamların salgın benzeri bir şekilde yayılmasını içeren bir durumu yansıtmaktadır. Bu tür yanlış bilgilere maruz kalmanın, profesyonel kaynaklardan gelen bilgiye doğal olarak güvenen hastaları tehlikeye atmakla kalmayıp, aynı zamanda tıbbi etik ve bilimsel doğruluğa olan kamu güvenini de zedelemektedir. Ayrıca, bu durum tedavi reddine ve olumsuz sağlık sonuçlarına da katkıda bulunmaktadır. Bu sorunları değerlendiren kapsamlı küresel düzenlemelerin yetersizliği, acilen daha etkili uygulama önlemlerine gereksinim olduğunu ortaya çıkarmaktadır.Conference Object Inverse Spectral Problems for Complex Jacobi Matrices(Springer New York LLC, 2013) Guseinov,G.S.The paper deals with two versions of the inverse spectral problem for finite complex Jacobi matrices. The first is to reconstruct the matrix using the eigenvalues and normalizing numbers (spectral data) of the matrix. The second is to reconstruct the matrix using two sets of eigenvalues (two spectra), one for the original Jacobi matrix and one for the matrix obtained by deleting the last row and last column of the Jacobi matrix. Uuniqueness and existence results for solution of the inverse problems are established and an explicit procedure of reconstruction of the matrix from the spectral data is given. It is shown how the results can be used to solve finite Toda lattices subject to the complex-valued initial conditions. © Springer Science+Business Media New York 2013.Conference Object Citation - WoS: 1Citation - Scopus: 3Boundary Element Method for Optical Force Calibration in Microfluidic Dual-Beam Optical Trap(Spie-int Soc Optical Engineering, 2015) Solmaz, Mehmet E.; Cetin, Barbaros; Baranoglu, Besim; Serhathoglu, Murat; Biyikh, Neemi; Serhatloglu, Murat; Biyikli, NecmiThe potential use of optical forces in microfluidic environment enables highly selective bio-particle manipulation. Manipulation could be accomplished via trapping or pushing a particle due to optical field. Empirical determination of optical force is often needed to ensure efficient operation of manipulation. The external force applied to a trapped particle in a microfluidic channel is a combination of optical and drag forces. The optical force can be found by measuring the particle velocity for a certain laser power level and a multiplicative correction factor is applied for the proximity of the particle to the channel surface. This method is not accurate especially for small microfluidic geometries where the particle size is in Mie regime and is comparable to channel cross section. In this work, we propose to use Boundary Element Method (BEM) to simulate fluid flow within the micro-channel with the presence of the particle to predict drag force. Pushing experiments were performed in a dual-beam optical trap and particle's position information was extracted. The drag force acting on the particle was then obtained using BEM and other analytical expressions, and was compared to the calculated optical force. BEM was able to predict the behavior of the optical force due to the inclusion of all the channel walls.Conference Object Host Based Dynamic Throughput Maximization Model for Ieee 802.11 Wlan(2010) Koyuncu,M.; Gercek,M.K.; Ercan,T.As the demand for uninterrupted Internet access grows, the popularity of wireless communication increases. However, wireless communication has some problems compared to conventional wired communication. Especially, if widely used Wireless Local Area Network (WLAN) applications are taken into consideration, it becomes an important issue to balance the load among available access points. It is impossible to balance the load when wireless hosts associate with an access point by using the classical approach of Received Signal Strength Index (RSSI). Some solutions containing a central server, requiring a specific brand of access point or protocol revisions have been proposed previously, but none of them has been favored as a generally accepted solution. In this study, a proposal which is central server free and requires no modifications to the existing infrastructure is presented. The proposed model is based on a dynamic determination of the least loaded access point to associate with, in order to balance load and maximize throughput. © Springer-Verlag Berlin Heidelberg 2010.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 Hisse Senedi Getirileri, Bitcoin Getirileri ve Riskten Kaçınma Arasındaki İlişki: Çok Değişkenli Bir Garch Modelinden Kanıtlar(Sosyoekonomi Soc, 2021) Sivrikaya, Ayşen; İren, Perihan; Omay, TolgaBu çalışma, çok değişkenli bir GARCH modeli kullanarak ABD Dow Jones Borsasında işlem gören hisse senedi getirileri, Bitcoin getirileri ve bunların belirsizlikleri arasındaki ilişkileri araştırmaktadır. Özellikle, yüksek ve düşük olmak üzere farklı risk iştahının ve getirilerde belirsizliğin yüksek olduğu dönemlerde Bitcoin ve ABD hisse senedi getirilerinin verdiği tepkileri karşılaştırmaktadır. Sonuçlar, Bitcoin getirisinin riskten kaçınılan veya yüksek belirsizliğin olduğu dönemlerde hisse senedi gibi tepki verdiğini, ancak iki getiri arasındaki ilişkinin sürdürülebilir olmadığını göstermektedir. Öte yandan, ABD borsa yatırımcıları tüm örneklem dönemi boyunca riskten kaçınma davranışını gösterirken, Bitcoin yatırımcıları aynı davranışı göstermemektedir.Conference Object Citation - WoS: 1Citation - Scopus: 1Deep Learning-Based Covid-19 Detection Using Lung Parenchyma Ct Scans(Springer international Publishing Ag, 2022) Kaya, Zeynep; Kurt, Zuhal; Koca, Nizameddin; Cicek, Sumeyye; Isik, SahinDuring the outbreak of the COVID-19 pandemic, it is important to improve early diagnosis using effective ways in order to lower the risks and further spread of the viruses as early as possible. This is also important when it comes to appropriate treatments and the reduction of mortality rates. In this respect, computer tomography (CT) scanning is a useful technique in detecting COVID-19. The present paper, as such, is an attempt to contribute to this process by generating an open-source, CT-based image dataset. This dataset contains the CT scans of lung parenchyma regions of 180 COVID-19 positives and 86 COVID-19 negative patients, all from Bursa Yuksek Ihtisas Training and Research Hospital. The experimental studies demonstrate that this dataset is effectively utilized deep learning-based models for diagnostic purposes. Firstly, a smart segmentation mechanism based on the k-means algorithm is applied to this dataset as a pre-processing stage. Then, the performance of the proposed method is evaluated using InceptionV3 and Xception convolutional neural networks, yielding a 96.20% and 96.55% accuracy rate and 95.00% and 95.50% F1-score, respectively. These state-of-the-art models are observed to detect COVID-19 cases faster and more accurately. In addition, the fine-tuning stage of the convolutional neural network (CNN) features sufficiently improves this accuracy rate. For these features, the support vector machine (SVM) classifier is used, resulting in remarkable 96.76% accuracy rate and 95.81% F1-score. The implications of the proposed method are immense both for present-day applications as well as future developments.
