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Article Citation - Scopus: 1An Investigation on the Dna Binding Activities of Melamine, Cyanuric Acid and Uric Acid(Editura Acad Romane, 2021) Senol, Ali; Devrim, Alparslan Kadir; Sudagidan, Mert; Ozalp, Veli CengizMelamine can be added to various foods such as milk, milk powder, baby food, pet, and livestock feed for cheating purposes due to its high nitrogen content. Regarding its usage in food products, there is a need to investigate its possible interactions with DNA. Thus, this study aimed to investigate the interactions of melamine and its metabolized products, cyanuric acid and uric acid with genomic DNA, isolated from eukaryotic (calf thymus) and prokaryotic (Staphylococcus aureus) sources. UV-absorbance spectrophotometry, fluorescence spectrophotometry, and agarose gel electrophoresis techniques were used to evaluate these interactions. The five different concentrations of melamine, cyanuric acid, and uric acid were incubated with fixed DNA concentration and it was determined that the test compounds interacted with the DNA molecules. The data obtained by UV-absorbance and fluorescence spectrophotometry techniques revealed an increase in wave peaks observed with the increasing substance concentration. After the obtained data of the aforementioned techniques were evaluated together, it was concluded that melamine, cyanuric acid, and uric acid bonded to the eukaryotic and prokaryotic genomic DNA materials via groove binding.Article Citation - WoS: 11Citation - Scopus: 15A Study on the Performance Evaluation of Wavelet Decomposition in Transient-Based Radio Frequency Fingerprinting of Bluetooth Devices(Wiley, 2022) Almashaqbeh, Hemam; Dalveren, Yaser; Kara, AliRadio frequency fingerprinting (RFF) is used as a physical-layer security method to provide security in wireless networks. Basically, it exploits the distinctive features (fingerprints) extracted from the physical waveforms emitted from radio devices in the network. One of the major challenges in RFF is to create robust features forming the fingerprints of radio devices. Here, dual-tree complex wavelet transform (DT-CWT) provides an accurate way of extracting those robust features. However, its performance on the RFF of Bluetooth transients which fall into narrowband signaling has not been reported yet. Therefore, this study examines the performance of DT-CWT features on the use of transient-based RFF of Bluetooth devices. Initially, experimentally collected Bluetooth transients from different smartphones are decomposed by DT-CWT. Then, the characteristics and statistics of the wavelet domain signal are exploited to create robust features. Next, the support vector machine (SVM) is used to classify the smartphones. The classification accuracy is demonstrated by varying channel signal-to-noise ratio (SNR) and the size of transient duration. Results show that reasonable accuracy can be achieved (lower bound of 88%) even with short transient duration (1024 samples) at low SNRs (0-5 dB).Article Citation - WoS: 5Citation - Scopus: 5Covid-19 Infection in Peritoneal Dialysis Patients: \ra Comparative Outcome Study With Patients on \rhemodialysis and Patients Without Kidney Disease(Aves, 2022) Kazancıoğlu, Rümeyza; Ozturk, Savas; Turgutalp, Kenan; Gürsu, Meltem; Arıcı, Mustafa; Oruç, Ayşegül; Ateş, KenanObjectives: There is limited data about coronavirus disease-19 (COVID-19) characteristics and results in peritoneal dialysis \r(PD) patients. This study aimed to investigate the characteristics and outcomes among PD patients and compare them with \rmatched hemodialysis (HD) patients and a control group without kidney disease.\rMethods: We included 18 PD patients and consecutive age- and gender-matched 18 HD and 18 patients without kidney \rdisease (control group) registered into the Turkish Society of Nephrology database including 1301 COVID-19 patients. We \rcompared demographic, clinical, radiological, laboratory data, and outcomes namely intensive care unit (ICU) admission, \rmechanical ventilation, mortality, and composite outcome (death and/or ICU admission).\rResults: ICU admission, mechanical ventilation, and mortality rates in PD patients (27.8%, 22.2%, and 22.2%, respectively) \rand the HD group (16.7%, 11.1%, and 16.7%, respectively) were higher than the control group (11.1%, 11.1%, and 5.6%, \rrespectively), but intergroup comparison did not reveal difference. A total of 11 (20.3%) patients had composite outcome \r(6 PD patients, 3 HD patients, and 2 patients in the control group). In Cox regression analysis, higher age and higher CRP level were related to increased risk of composite outcome. Adjusted rate of composite outcome in PD group was significantly higher than \rthe control group (P = .050). This rate was similar in HD and control groups (P = .30).\rConclusions: Combined in-hospital mortality and/or ICU admission of PD patients with COVID-19 was significantly higher than the control \rpatients. There is a need for careful surveillance of PD patients for infection signs and prompt treatment of COVID-19.Article Citation - WoS: 3Evaluation of Students' Opinions Regarding Distance Learning Practices in Turkish Universities During the Covid-19 Pandemic(Tuba-turkish Acad Sciences, 2021) Isik, Oguz; Tengilimoglu, Dilaver; Tekin, Perihan Senel; Tosun, Nurperihan; Zekioglu, AysuThe purpose of this study is to identify hether students at Turkish universities are having difficulties in the distance learning process and to reveal their opinions regarding the system. Using a cross-cultural survey design, data were collected from 5052 students. Based on the collected data, 58.5% of the students have asynchronous distance learning classes in their universities. Access to distance learning classes is one of the problems, and it is attributed to computers, internet, and connectivity issues as well as with starting the lessons too early or late. A majority of participants (73.7%) found class materials uploaded by lecturers to distance learning systems to be sufficient or partially sufficient, and 36.7% stated that they had problems accessing resources regarding their homework. Students' satisfaction level with the distance learning system scored 4.4 out of 10. According to the evaluation regarding whether the level of satisfaction of participants varied across the type of university, the satisfaction level of students in public universities is generally low (score of 4.3 out of 10) compared to satisfaction in foundation universities (4.9 out of 10).Article Citation - WoS: 2Citation - Scopus: 2Protective Effect of Aerobic Exercise on the Nasal Mucosa of Rats Against the Histopathologic Changes in Cigarette Smoke Exposure(Sage Publications inc, 2020) Akkoca, Ozlem; Unlu, Ceren Ersoz; Tatar, Ilkan; Sargon, Mustafa Fevzi; Zeybek, Dilara; Oguztuzun, SerpilIntroduction: Smoking is a public health problem that has been proven to have adverse effects on human health. Aerobic exercise has positive effects on the human body, especially on the respiratory system. Objective: The aim of this experimental animal model study was to determine whether regular aerobic exercise has a protective effect against the harmful effects of cigarette smoke on the nasal mucosa of rats. Methods: A total of 24 male Wistar albino rats were randomly separated into 3 groups of 8: group 1 (cigarette smoking), group 2 (cigarette smoking and exercise), and group 3 (control group). At the end of the experiment period, histopathological (light and electron microscopy) and immunohistochemical (GSTA 1, CYP1A1, and CYP2E1) evaluations were made of the nasal mucosa of the animals. Results: Goblet cell loss and basal membrane thickening were significantly lower in group 2 and group 3 compared to group 1. In the electron microscope evaluation, the inflammatory expressions of the goblet cells were observed in a very small area in group 2. In group 1, these were distributed over large areas between the mucosal cells. There was seen to be significant swelling of the mitochondria in group 1 compared to the other groups. No statistically significant difference was determined between the groups with respect to GSTA1, CYP2E1, and CYP1A1 scores (P> .05). Conclusion: The results of this study showed that regular aerobic exercise has a protective effect against the harmful effects of smoking on the nasal mucosa of rats.Article Citation - WoS: 1Syntactic Scrambling in Broca’s Aphasia: a Turkish Sample(S. Karger AG, 2025) Arslan, B.; Çiyiltepe, M.M.; Karaman, M.Introduction: Broca’s aphasia (BA) is a language disorder that causes grammatical errors in the language production skills of patients. Contemporary studies revealed the fact that patients with BA (PBA) also have difficulty in analyzing the meaning of phrases and sentences and comprehending the real meaning of the discourse produced by the speaker. The purpose of this study was to investigate possible effect of syntactic movement by changing the word positions in the sentence with morphological markers in order to produce clauses without changing the meaning on the phrasal comprehension skills of Turkish-speaking patients with BA. Method: A total of 300 participants were divided as study (n = 150) and control (n = 150) groups between ages of 27–89. A test that included 20 relative clauses and 9 noun clauses (in total 29 phrases) was assigned to the PBA and the control group (CG). Relative clause phrases originated from simple sentences by adding suffixes to the verb as a function of Turkish morphology. Each suffix indicated a specific noun, object, or subject, and each figure in the test was related to one of them. A researcher asked participants to match the demanded clause with the 6 possibly related pictures for relative clause and 3 for noun clauses. Results: Findings indicated that BA patients in our study had a lack of comprehending relative clauses due to the syntactic movement of words in the object and subject positions. Compared to the responses of the CG, PBA had significantly lower scores when the object and subject positions have moved from their original positions. BA patients also obtained significantly lower scores in object type questions. Conclusion: Our findings support the fact that comprehension processing in PBA should be investigated profoundly to be able to understand the nature of the disorder in different languages. In Turkish, syntactic movement of words to form a relative clause caused the BA patients to have significant problems to assign the semantic roles to the words in the existence of movement or change in their original positions. © 2025 S. Karger AG, Basel.Article Citation - WoS: 3Citation - Scopus: 4Semptomatik Çok Ciddi Aort Darlıklı Hastalarda Transkateter Aort Kapak İmplantasyonun Etkisi(Kare Publ, 2021) Karaduman, Bilge Duran; Ayhan, Hüseyin; Keles, Telat; Bozkurt, EnginAmaç: Aort darlığı (AD) ilerleyici bir hastalıktır ve tek tedavi seçeneği olan kapak replasmanı semptomatik hale geldikten sonra ve geri dönüşümsüz miyokardiyal hasar gelişmeden önce yapılmalıdır. Çok ciddi aort darlığı (ÇCAD) hastalarında cerrahi kapak replasmanı asemptomatik olsa bile önerilmektedir. Ancak ÇCAD hastalarında transkateter aortik kapak implantasyonunun (TAVI) etkisi hakkında ayrıntılı bir çalışma yoktur. Bu çalışmada amacımız, semptomatik ÇCAD hastalarında TAVI’nin uygulanabilirliğini ve güvenilirliğini göstermektir. Yöntemler: Merkezimizde TAVI uygulanan toplam 505 ardışık semptomatik AD hastası retrospektif olarak incelendi. Hastaların ortalama yaşı 77.8±7.6 yıl ve %56.4 kadın idi. Hastalar ÇCAD grubu (n: 134 hasta) ve yüksek gradyentli AD grubu (YGAD, n: 371 hasta) olarak iki gruba ayrıldı. Bulgular: ÇCAD grubunda daha fazla kadın cinsiyet, daha yüksek sol ventrikül ejeksiyon (SV) fraksiyonu, daha fazla küçük SV, hipertrofik SV, daha fazla normal koronerler ve daha az koroner arter hastalığı, bypas cerrahisi, miyokard enfarktüsü ve atriyal fibrilasyon öyküsü vardı. Predilatasyon ve Edwards SAPIEN 3 ÇCAD grubunda olarak daha az kullanıldı. VARC-2 kriterlerine göre majör komplikasyonlar ve hastane içi mortalitede (ÇCAD grubu; 5 hasta, YG AD grubu; 16 hasta, p: 0.769) istatistiksel fark saptanmadı. İki grup arasında Cox regresyon modeli sağ kalım eğrisinde ÇCAD lehine istatistiksel olarak anlamlı fark vardı (p<0.001). Sonuç: Bu çalışmamız ile semptomatik çok ciddi aort darlığında TAVI’nin kabul edilebilir komplikasyon ve daha yüksek sağ kalım oranları ile uygulanabilir ve güvenli olduğu gösterilmiştir. Hâlihazırda cerrahi kapak replasmanı endikasyonu olan asemptomatik ÇCAD hastalarında TAVI uygulanabilmesi için daha fazla randomize büyük çalışma gereklidir.Review Citation - Scopus: 3Reconsidering Development Aid: a Systemic Analysis(Pluto Journals, 2020) Gülseven,Y.In the political and academic debates on development aid in the post-Cold War years, there is often reference to a “new aid architecture.” This study explores what is new about this “new architecture of aid” and traces change and continuity by comparing the form and essence of aid architecture in the Cold War and the post-Cold War years. It discusses to what extent development aid can be interrogated within the inter-systemic competition during the Cold War period. After having located aid into a systemic framework, it seeks to understand the emergence of the “new aid architecture” in the post-Cold War years. To this end, it first analyses the relevance of aid to the hegemonic project that pursues the proletarianization of the world’s poor. It then focuses on aid’s role in transforming social and industrial relations to promote capitalist competitiveness at the global level. In this respect, it pays particular attention to “global value chains.” This study argues that “new aid architecture” is nothing more than an attempt to set a new framework for the role and contribution of aid in expanding and deepening the hegemony of capital over labor on a global scale in the absence of the Soviet factor. © 2020 Pluto Journals. All rights reserved.Article Citation - WoS: 5Doğrusal Olmayan Birim Kök Testleri Kullanılarak 21 Oecd Ülkesinde Sağlık Harcamaları Yakınsamasının Test Edilmesi(Duzce Univ, Fac Medicine, 2022) Çelik, Eşref Uğur; Omay, Tolga; Tuzlukaya, ŞuleAmaç: Bu çalışma, 1975 ve 2019 yılları için 21 OECD ülkesinde sağlık harcamalarının stokastik zaman serisi davranışını bir dizi güncel birim kök testi kullanarak analiz etmeyi amaçlamaktadır. Gereç ve Yöntem: Bu çalışmada, 21 OECD ülkesinin sağlık harcaması verilerinin bu ülkelerin sağlık harcamaları arasında bir yakınsama olup olmadığını ampirik olarak test etmek için doğrusal ADF birim kök testi ve sekiz ilgili doğrusal olmayan birim kök testi kullanılmıştır. Bulgular: Ampirik bulgular, 21 OECD ülkesinin 20'sinde sağlık harcamalarının durağanlığını desteklemektedir. Sonuç: OECD ülkelerinin çoğunda sağlık yakınsama hipotezi doğrulanmış olup, sağlık harcamaları şoklarının ülke düzeyinde sağlık harcamaları üzerinde yalnızca geçici etkileri olduğunu göstermektedir. Bu ampirik çalışma çok önemli politika sonuçları sunmaktadır. Politika otoritelerinin alacağı politika tedbirlerinin sağlık harcamaları verisindeki olası doğrusal olmayanlığı göz ardı edilerek yapılamayacağı çalışmanın ampirik kısmında teyit edilmiştir. Sonuç kısmında sıralanan politika önerilerine alt rejim dönemlerinde daha fazla yatırım yapılması ve yüksek rejim dönemlerde ise var olanın sürdürülmesinin sağlık harcamaları yakınsaması için yeter koşul sağladığı belirlenmiştir. Bunun yanı sıra Japonya ve Güney Kore gibi ülkelerde rejimden bağımsız yapısal değişimlerin sağlık harcamaları yakınsamasında da değişim yarattığı belirlenmiştir. Bu tarz ülkelerde yapısal değişimler gözetilerek yatırımların yapılması önem arz etmektedir.Article Altının Riskten Korunma Etkinliği: Farklı Dinamik Portföy Yaklaşımları İle Bankacılık Sektörü İçin Bir Analiz(2022) Ozdemir, HuseyinBu çalışmada minimum varyans, minimum korelasyon ve minimum bağlantılılık yaklaşımları ile altın ve altı büyük bankanın (İş Bankası, Garanti Bankası, Akbank, Yapı Kredi Bankası, Halkbank ve Vakıfbank) hisse senedinden oluşan portföyün finansal analizi yapılmıştır. Çalışmanın amacı altının Türkiye’de faaliyet gösteren altı büyük banka hisse senetlerine karşı finansal koruma sağlayıp sağlamadığının araştırılmasıdır. Ayrıca bu çalışmada altının finansal koruma etkinliğinin ölçülmesi de amaçlanmıştır. Analiz edilen veriler günlük frekansta olup gözlem dönemi 01.01.2018- 08.11.2022 arasını içermektedir. Çalışma kapsamında kullanılan portföy oluşturma yaklaşımı TVP-VAR modelinden elde edilmiştir. Ampirik sonuçlar, zamana ve portföy oluşturma yaklaşımına bağlı olarak altının banka hisse senetleri içindeki optimal oranının %39 ile %53 oranında değiştiğini göstermektedir. Oluşturulan portföylerde söz konusu bankaların hisse senedi oynaklıklarının yaklaşık %75 oranında azaldığı gözlemlenmiştir. MCP ve MCoP yaklaşımları ile karşılaştırdığında en yüksek kümülatif getirinin olduğu yaklaşım MVP yaklaşımıdır. Ayrıca, çalışma kapsamında elde edilen bulgular altının ayı piyasasında banka hisse senetleri için iyi bir finansal koruma sağladığını göstermektedir.
