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Article Transmission Eigenvalues Problem of a Schrödinger Equation(Tubitak Scientific & Technological Research Council Turkey, 2024) Yıldırım, Emel; Baıramov, ElgizIn this paper, transmission eigenvalues of a Schrödinger equation have been studied by constructing a new inner product and using Weyl theory. Necessary conditions for these eigenvalues to be negative, real, and finite have been examined. This method has provided a new framework related to transmission eigenvalue problems and the investigation of their properties. The conclusions have been verified for the special case of the problem.Article Citation - WoS: 6Citation - Scopus: 6The Role of Anakinra in the Modulation of Intestinal Cell Apoptosis and Inflammatory Response During Ischemia/Reperfusion(Tubitak Scientific & Technological Research Council Turkey, 2021) Kandemir, Muhammed; Bektur Aykanat, Nuriye Ezgi; Yaşar, Necdet Fatih; Özkurt, Mete; Özyurt, Rumeysa; Aykanat, Nuriye Ezgi Bektur; Erkasap, Nilüfer; Bektur Aykanat, Nuriye Ezgi; Basic Sciences; Basic SciencesBackground/aim: Even though interleukin-1 receptor antagonist, IL-1Ra, is used in certain inflammatory diseases, its effect on ischemia-reperfusion injury is a current research topic. We aimed to investigate the protective effects of anakinra, an IL-1Ra, on the I/R induced intestinal injury. Materials and methods: The rat model of intestinal ischemia-reperfusion was induced. Rats were randomized into 4 groups: (group 1) control group, (group 2) I/R group, (group 3 and 4) treatment groups (50 mg/kg and 100 mg/kg, respectively). Gene expressions of caspase-3, TNF-α, IL-1α, IL-6, and apoptotic cells in tissue samples were evaluated by PCR and TUNEL methods, respectively. Plasma levels of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) were studied by the ELISA method and tissue samples were examined histopathologically as well. Results: Anakinra inhibited the expression of IL-1α, IL-6, and TNF-α and decreased the SOD, CAT, and MDA caused by ischemiareperfusion injury in both treatment groups. Caspase-3 expression and TUNEL-positive cell number in treatment groups were also less. Histopathologically, anakinra better preserved the villous structure of the small intestine at a dose of 100 mg/kg than 50 mg/kg.Conclusion: Anakinra decreased the intestinal damage caused by ischemia-reperfusion and a dose of 100 mg/kg was found to be histopathologically more effective.Key words: Ischemia reperfusion injury, interleukin-1 receptor antagonist, anakinraArticle Citation - WoS: 1Citation - Scopus: 1Short-Term Effectiveness of Epidermis Dermis Fascia Kinesiotaping Technique in Myofascial Pain Syndrome on Upper Trapezius: a Multi-Center, Double-Blind, Randomized Clinical Study(Baycinar Medical Publ-Baycinar Tibbi Yayincilik, 2024) Ayhan, Fikriye Figen; Külcü, Duygu Geler; Keleş, Elif Çiğdem; Dinç, Arzu; Mesci, Nilgün; Çakmak, Bahar; Yılmaz, Zeynep AlpoğuzObjectives: This study aims to investigate the efficacy of epidermis dermis fascia (EDF) kinesiotaping (KT) technique on pain intensity, number of active trigger points (TrPs), cervical range of motion (ROM) angles, and disability levels in patients with myofascial pain syndrome (MPS) on upper trapezius (UT) muscle. Patients and methods: Between January 2019 and January 2020, a total of 180 patients (21 males, 159 females; mean age: 35.9±9.0 years; range, 18 to 56 years) with MPS were included. The patients were randomized into either KT with EDF technique (Group 1) or sham KT (Group 2). Outcome measures were Visual Analog Scale (VAS) pain score, number of active TrPs, cervical ROM angles, and Neck Pain Disability Scale (NPDS). Results: Both groups improved in terms of all outcome parameters except for cervical flexion and extension angles in Group 2. The VAS pain scores significantly decreased in Group 1 (p<0.05), compared to Group 2. The number of active TrPs (p=0.001) and NPDS scores (p=0.016) of Group 1 significantly improved than Group 2. Cervical flexion (p=0.001), extension (p=0.001), and left and right lateral flexion angles (p<0.0001) significantly improved in Group 1. Cervical left (p=0.001) and right (p<0.0001) lateral flexion angles significantly improved in Group 2. There was no significant difference between the groups regarding cervical ROM angles. Conclusion: Our study results suggest that KT with the EDF technique is an effective method in reducing pain and number of active TrPs, improving disability and cervical ROM angles.Article An Exhaustive Computer Search for Finding New Curves With Many Points Among Fibre Products of Two Kummer Covers Over $\\bbb{f}_5$ and $\\bbb{f}_7$(2013) Özbudak, Ferruh; Temür, Burcu Gülmez; Yayla, OğuzIn this paper we make an exhaustive computer search for finding new curves with many points among fibre products of 2 Kummer covers of the projective line over F5 and F7 . At the end of the search, we have 12 records and 6 new entries for the current Table of Curves with Many Points. In particular, we observe that the fibre product $y^3_1$ = $\\frac {5(x+2)(x +5)} {x}$, $y^3_2$ $\\frac {3x^2(x +5)} {x + 3}$ over F7 has genus 7 with 36 rational points. As this coincides with the Ihara bound, we conclude that the maximum number N7 (7) of F7 -rational points among all curves of genus 7 is 36. Our exhaustive search has been possible because of the methods given in the recent work by Özbudak and Temür (2012) for determining the number of rational points of such curves.Article Citation - WoS: 1Citation - Scopus: 2Role of Surveillance Screening in Detecting Tumor Recurrence After Treatment of Childhood Cancers(Aves, 2021) Kısa, Pelin Teke; Emir, SunaObjective: As the survival rates in children with cancer reach up to 80%, this improvement in survival increases the number of patients under follow-up. After cancer treatment is completed, patients are taken to follow-up surveillance to ensure the early detection of recurrence and the late effects of treatments. The frequency and necessity of surveillance screening tests are controversial. This study aimed to assess the efficacy of surveillance screening in the detection of recurrence. Material and methods: The files of 533 children who were diagnosed as having cancer at our pediatric oncology clinic between 2004 and 2013 were retrospectively evaluated. We looked at outcomes after recurrence, the timing and pattern of recurrence, the presence of symptoms during recurrence, physical examination findings, tumor marker levels, laboratory findings, and radiologic tests. Results: Of the 63 patients with recurrence, 23 were symptomatic and 40 were asymptomatic at the time of the recurrence. Tumor location and time of the recurrence did not affect the post recurrence survival. The median post-recurrence survival for patients was 13 (range, 1-98) months. The median post-relapse survival was 10 (range, 1-73) months in patients with symp-tomatic recurrence, and 16 (range, 1-98) months in patients with asymptomatic recurrence. It was determined that patients in whom recurrence was identified with surveillance tests had longer post-relapse survival time. The 5-year survival rate of 23 patients with symptomatic recurrence was 12.2%; this rate was 49.5% in asymptomatic patients (p<0.05).Conclusions: It should be considered that surveillance testing offers the benefit of prolonging post recurrence survival.Article Citation - WoS: 1The Socio-Economic Impact of the Covid-19 Pandemic on Syrian Refugees in Turkey(Uluslararasi Iliskiler Konseyi dernegi, 2024) Memisoglu, Fulya; Ozkil, Altan; Kilinc, TunaBuilding upon empirical research, this study examines the socio-economic impact of the Covid-19 pandemic on Syrian refugees in Turkey by analyzing its implications on employment, livelihood opportunities, and social cohesion. More specifically, it focuses on the experiences of Syrian refugees to examine the ways in which they exert their agency to cope with the structural constraints when faced with 'multiple crises' in host countries, intersecting with the dynamics of a 'normalized refugee crisis'. Our findings from fieldwork conducted in the top six refugee-hosting cities reveal that loss of jobs, limited access to decent work, increased dependency on external financial assistance, and social exclusion have been some of the most acute effects of the pandemic on refugees. Meanwhile, the perceived effects that refugees have on the host community's welfare trigger problems that impede social cohesion. All in all, the study intends to highlight the far-reaching effects of the pandemic beyond its direct health implications by addressing the structural vulnerability of refugees and the importance of providing an enabling environment for socio-economic self-reliance.Article A Note on the Generalized Matsumoto Relation(2017) Dalyan, Elif; Medetoğulları, Elif; Pamuk, MehmetcikWe give an elementary proof of a relation, first discovered in its full generality by Korkmaz, in the mapping class group of a closed orientable surface. Our proof uses only the well-known relations between Dehn twists.Article Citation - WoS: 3Citation - Scopus: 5Investigation of the Effect of Hyperthyroidism on Endoplasmic Reticulum Stress and Transient Receptor Potential Canonical 1 Channel in the Kidney(Tubitak Scientific & Technological Research Council Turkey, 2021) Aykanat, Nuriye Ezgi Bektur; Şahin, Erhan; Kaçar, Sedat; Bağcı, Rıdvan; Karakaya, Şerife; Dönmez, Dilek Burukoğlu; Şahintürk, VarolBackground/aim: Hyperthyroidism is associated with results in increased glomerular filtration rate as well as increased renin-angiotensin-aldosterone activation. The disturbance of Ca2+ homeostasis in the endoplasmic reticulum (ER) is associated with many diseases, including diabetic nephropathy and hyperthyroidism. Transient receptor potential canonical 1 (TRPC1) channel is the first cloned TRPC family protein. Although it is expressed in many places in the kidney, its function is uncertain. TRPC1 is involved in regulating Ca2+ homeostasis, and its upregulation increases ER Ca2+ level, activates the unfolded protein response, which leads to cellular damage in the kidney. This study investigated the role of TRPC1 in the kidneys of hyperthyroid rats in terms of ER stress markers that are glucose-regulated protein 78 (GRP78), activating transcription factor 6 (ATF6), (protein kinase R (PKR)-like endoplasmic reticulum kinase) (PERK), Inositol-requiring enzyme 1 (IRE1). Materials and methods: Twenty male rats were assigned into control and hyperthyroid groups (n = 10). Hyperthyroidism was induced by adding 12 mg/L thyroxine into the drinking water of rats for 4 weeks. The serum-free T3 and T4 (fT3, fT4), TSH, blood urea nitrogen (BUN), and creatinine levels were measured. The histochemical analysis of kidney sections for morphological changes and also immunohistochemical and western blot analysis of kidney sections were performed for GRP78, ATF6, PERK, IRE1, TRPC1 antibodies. Results: TSH, BUN, and creatinine levels decreased while fT3 and fT4 levels increased in the hyperthyroid rat. The morphologic analysis resulted in the capillary basal membrane thickening in glomeruli and also western blot, and immunohistochemical results showed an increase in TRPC1, GRP78, and ATF6 in the hyperthyroid rat (p < 0.05). Conclusion: In conclusion, in our study, we showed for the first time that the relationship between ER stress and TRPC1, and their increased expression caused renal damage in hyperthyroid rats.Key words: Hyperthyroidism, endoplasmic reticulum (ER) stress, transient receptor potential canonical 1 (TRPC1), kidney, ratArticle Fedja’s Proof of Deepti’s Inequality(Tubitak Scientific & Technological Research Council Turkey, 2018) Ostrovska, Sofiya; Turan, MehmetThe paper aims to present, in a systematic way, an elegant proof of Deepti’s inequality. Both the inequalityand various ideas concerning the issue were discussed on the Mathoverflow website by a number of users, but none haveappeared in the literature thus far. In this work, suggestions pertaining to users ‘Deepti’ and ‘fedja’ are traced, whencethe title. The results or the paper are new, and the proof is divided into a series of statements, many of which are ofinterest in themselves.Article A Wavelet-Based Feature Set for Recognizing Pulse Repetition Interval Modulation Patterns(2016) Gençol, Kenan; At, Nuray; Kara, AlıThis paper presents a new feature set for the problem of recognizing pulse repetition interval (PRI) modulation patterns. The recognition is based upon the features extracted from the multiresolution decomposition of different types of PRI modulated sequences. Special emphasis is placed on the recognition of jittered and stagger type PRI sequences due to the fact that these types of PRI sequences appear predominantly in modern electronic warfare environments for some specific mission requirements and recognition of them is heavily based on histogram features. We test our method with a broad range of PRI modulation parameters. Simulation results show that the proposed feature set is highly robust and separates jittered, stagger, and other modulation patterns very well. Especially for the stagger type of PRI sequences, wavelet-based features outperform conventional histogram-based features. Advantages of the proposed feature set along with its robustness criteria are analyzed in detail.
