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Article Influence of Synthesis Parameters on the Structural Formation of Mayenite via the Citrate Sol-Gel Method(Tubitak Scientific & Technological Research Council Turkey, 2025) Eryildirim, Busra; Oktar, Nuray; Dogu, DorukMayenite (Ca12Al14O33) has remarkable properties such as high oxygen mobility, ionic conductivity, and catalytic activity. It has many different applications, including oxide-conducting electrolytes, fluorescent lamps, moisture sensors, hydrogen-permeable membranes, oxygen pumps, hydrogen storage, and catalysis. However, pure and homogeneous mayenite synthesis parameters have not yet been fully explored. This study examines the effect of synthesis parameters including metal salt (MS) to citric acid (CA) molar ratios (1:1 and 1:2), pH (0.4-2), and calcination temperature (900-1200 degrees C) in citrate sol-gel method on the crystal structure of mayenite. Synthesized materials were examined by thermogravimetric (TG), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N2 adsorption-desorption, scanning electron microscopy (SEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), Fourier-transform infrared spectroscopy (FTIR), and pyridine adsorbed diffuse reflectance Fourier-transformed infrared spectroscopy (DRIFTS) analyses. The results show that all 3 parameters contribute to the mayenite phase formation and different impurity phases can be observed depending on the synthesis parameters. With no pH adjustment and an MS to CA ratio of 1, other phases of calcium aluminate mostly form. Mayenite becomes the main phase by doubling the CA amount. Besides CA, pH is also an important factor in mayenite synthesis. When the pH was adjusted to 2 with the MS to CA ratio at 1:1, mayenite was formed as the main phase, but other phases of calcium aluminate were also observed in the structure. XRD results show that all parameters studied influence the crystal structure of the final material, including the calcination temperature. This study shows that pure mayenite can be synthesized with a calcination temperature of 1200 degrees C, at a pH of 2, and the MS to CA molar ratio of 1:2.Article ISAR Imaging of Drone Swarms at 77 GHz(Tubitak Scientific & Technological Research Council Turkey, 2025) Coruk, Remziye Busra; Kara, Ali; Aydin, ElifThe proliferation of easily available, internet-purchased drones, coupled with the emergence of coordinated drone swarms, poses a significant security threat for airspace. Detecting these swarms is crucial to prevent potential accidents, criminal misuse, and airspace disruptions. This paper proposes a novel inverse synthetic aperture radar (ISAR) imaging technique for high-resolution reconstruction of drone swarms at 77 GHz millimeter wave (mmWave) frequency, offering a valuable tool for military and defense antidrone systems. The key parameters affecting down-range and cross-range resolution (0.05 m), ultimately enabling the generation of detailed ISAR images are discussed. Here, we create diverse scenarios encompassing various swarm formations, sizes, and payload configurations by employing ANSYS simulations. To enhance image quality, different window functions are evaluated, and the Hamming window is selected due to its highest peak signal-to-noise ratio (PSNR) (16.3645) and structural similarity (SSIM) (0.9067) values, ensuring superior noise reduction and structural preservation. The results demonstrate that the effectiveness of high-resolution ISAR imaging in accurately detecting and characterizing drone swarms pave the way for enhanced airspace security measures.Article Citation - WoS: 1Citation - Scopus: 2Cannabinoid Receptor Ligands Modulate Fibrosis and Inflammation in Idiopathic Pulmonary Fibrosis: a Preliminary Study(Tubitak Scientific & Technological Research Council Turkey, 2024) Kose, Sevil; Onen, Selin; Gizer, Merve; Boduroglu, Esin; Gonullu, Ugur; Korkusuz, PetekBackground/aim: No specific pharmacological treatment regimen for idiopathic pulmonary fibrosis (IPF) exists. Therefore, new antiinflammatory therapeutic strategies are needed. Cannabinoids (CBs), known for their inflammation-modulating and antifibrotic effects, may be potential medication candidates for treating IPF. We aim to evaluate the inflammation-modulating and antifibrotic effects of CB receptor (CBR) agonists and antagonists in lipopolysaccharide-stimulated normal human lung fibroblast, epithelial cells, IPF fibroblast cells, and monocytes. Materials and methods: We detected CBRs in normal human lung fibroblasts (LL24) and IPF fibroblast cells (LL29), epithelial cells (A549) and monocytes (THP-1) by flow cytometry. We determined TGF-(31, IL-8, and TNF-alpha inflammatory cytokines in the LL24, LL29, A549, and THP-1 cell culture supernatants on days 1 and 5 by ELISA. We evaluated the cell viability in LL24, LL29, and A549 cells on days 1, 3, and 5 spectrophotometrically and detected collagen Type I (ColI) production in the LL24 and LL29 cell culture supernatants on days 1, 3, and 5 by ELISA. Results: LL24, LL29, A549, and THP-1 cells exhibited CB1 (CB1R) and CB2 (CB2R) receptors. CB1R and CB2R agonists WIN55,2122 and JWH015 inhibited fibroblastic and epithelial cell proliferation on day 5. TGF-(31 and TNF-alpha release increased, while IL-8 release decreased in LL24, LL29, A549, and THP-1 cells in response to the administration of WIN55,212-2 and JWH015 at a 10-2 mM concentration. CB1R and CB2R antagonists AM251 and AM630 did not block agonistic responses, suggesting a nonclassical CBRmediated pathway. CB2R agonist JWH015 decreased ColI expression in IPF lung fibroblasts LL29 on day 3. Conclusion: These results suggest that CB signaling regulates the progression of pulmonary inflammation and fibrosis via CBR activation. This may offer a potential pharmacological tool for developing antifibrosis therapies.Article Transmission Eigenvalues Problem of a Schrödinger Equation(Tubitak Scientific & Technological Research Council Turkey, 2024) Yıldırım, Emel; Baıramov, Elgiz; Bayram, ElgızIn 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 - Scopus: 1Electrochemical Copolymerization of Thiophene Containing Pseudo-Polyether Cages With Pyrrole(Tubitak Scientific & Technological Research Council Turkey, 2006) Cihaner, Atilla; Onal, Ahmet M.; Chemical EngineeringConducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (1). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF(6)) dissolved in acetonitrile. The spectroelectrochemical properties of the films were investigated using UV-VIS spectroscopy.Article On a Class of Permutation Trinomials Over Finite Fields(Tubitak Scientific & Technological Research Council Turkey, 2024) Temür, Burcu Gülmez; Özkaya, BuketIn this paper, we study the permutation properties of the class of trinomials of the form f (x) = x4q+1 + λ1xq+4 + λ2x2q+3 ∈ Fq2 [x] , where λ1, λ2 ∈ Fq and they are not simultaneously zero. We find all necessary and sufficient conditions on λ1 and λ2 such that f (x) permutes Fq2 , where q is odd and q = 22k+1, k ∈Article Citation - WoS: 13Citation - Scopus: 13Association between monocyte to high-density lipoprotein cholesterol ratio and bicuspid\raortic valve degeneration(Tubitak Scientific & Technological Research Council Turkey, 2020) Karaduman, Bilge Duran; Ayhan, Hüseyin; Keles, Telat; Bozkurt, Engin; Duran Karaduman, BilgeBackground/aim: From a pathophysiological point of view, inflammation is thought to be more dominant in bicuspid aortic valve\r(BAV) stenosis than tricuspid aortic valve (TAV) stenosis. Our study aimed to determine the association between monocyte to highdensity lipoprotein cholesterol (HDL-C) ratio (MHR), a new inflammatory marker, and the speed of progression of stenosis and\rpathophysiology of BAV stenosis.\rMaterials and methods: A total of 210 severe aortic stenosis patients (70 consecutive BAV patients, 140 matched TAV patients) were\rretrospectively enrolled in the study. Clinical and echocardiographic data and laboratory results related to our research were collected\rretrospectively from the patients’ records. MHR was measured as the ratio of the absolute monocyte count to the HDL-C value.\rResults: Seventy BAV (mean age: 72.0 ± 9.1 years, 42.9% female) and 140 TAV patients (mean age: 77.9 ± 8.3 years, 51.4% female)\rwith severe aortic stenosis were enrolled in this study. There was no difference between the two groups in terms of another baseline\rdemographic or clinic findings except age (P < 0.001). Monocyte count, hemoglobin level, mean platelet volume was significantly\rhigher, and HDL-C level was significantly lower in the BAV group, while other lipid and CBC parameters were found to be similar. In\rthe multivariate analysis, MHR (P = 0.005, 95% CI: 0.90–0.98) and, as expected, age (P = 0.001, 95% CI: 1.02–1.11) were found to be\rsignificant as the independent predictor of BAV, after adjusting for other risk factors.\rConclusion: Our study showed a significant correlation between increased MHR and BAV. MHR was determined as a significant\rindependent predictor for the speed of progression and diagnosis of severe BAV stenosis in multivariate analysis.Article Citation - WoS: 16Citation - Scopus: 19The Triglyceride-Glucose Index Predicts Peripheral Artery Disease Complexity(Tubitak Scientific & Technological Research Council Turkey, 2020) Karaduman, Bilge Duran; Ayhan, Hüseyin; Keles, Telat; Bozkurt, Engin; Duran Karaduman, BilgeBackground/aim: High levels of triglyceride (TG) and fasting blood glucose (FBG) values increase atherosclerosis risk. This study\revaluates the relationship between peripheral artery disease (PAD) severity and complexity, as assessed by TransAtlantic InterSociety\rConsensus-II (TASC-II) classification and the triglyceride-glucose (TyG) index.\rMaterials and methods: A total of 71 consecutive patients with PAD (males 93%, mean age 63.3 ± 9.7), who underwent percutaneous\rperipheral intervention were included retrospectively. The patients were divided into two groups according to the angiographically\rdetected lesions. Those with TASC A-B lesions were included in Group 1, and those with TASC C-D lesions were included in Group 2.\rTyG index was calculated as formula: ln[fasting TG (mg/dL) × fasting plasma glucose (mg/dL)/2].\rResults: There were 40 patients in Group 1 (90.3% men, with a mean age of 63.6 ± 9.3 years) and 31 patients in Group 2 (96.8% men,\rwith a mean age of 62.0 ± 8.6 years). In the majority of patients in both groups, the target vessels are iliac arteries and femoral arteries.\rIn Group 2, platelet count and TyG index were significantly high, according to Group 1. The TyG index was significantly correlated with\rTASC-II, Rutherford category, HbA1c, and HDL-C.\rConclusion: In this present study, we showed that the TyG index was an independent predictor of peripheral artery disease complexity,\raccording to TASC-II classification, for the first time in the literature.Article On Strongly Autinertial Groups(Tubitak Scientific & Technological Research Council Turkey, 2018) Onur, Cansu Betin; Betin Onur, CansuA subgroup X of G is said to be inert under automorphisms (autinert) if |X : $X^\\alpha$ ∩ X| is finite for allα ∈ Aut(G) and it is called strongly autinert if | < X, $X^\\alpha$ >: X| is finite for all α ∈ Aut(G). A group is calledstrongly autinertial if all subgroups are strongly autinert. In this article, the strongly autinertial groups are studied. Wecharacterize such groups for a finitely generated case. Namely, we prove that a finitely generated group G is stronglyautinertial if and only if one of the following hold:i) G is finite;ii) G = ⟨a⟩ ⋉ F where F is a finite subgroup of G and ⟨a⟩ is a torsion-free subgroup of G.Moreover, in the preliminary part, we give basic results on strongly autinert subgroups.Article 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.