Browsing by Author "Özdemir A."
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Item Fundamental theorems for the hyperbolic geodesic triangles(2005) Uǧurlu H.H.; Kazaz M.; Özdemir A.In this work, we state and prove the sine, cosine I, cosine II, sine-cosine and cotangent rules for spherical triangles on the hyperbolic unit sphere H02 in the Lorentzian space R13.Item The Cosine Rule II for a spherical triangle on the dual unit sphere S̃2(2005) Kazaz M.; Uǧurlu H.H.; Özdemir A.In this work, we proved the Cosine Rule II for a spherical triangle on the dual unit sphere S̃2. © Association for Scientific Research.Item Hyperbolic sine and cosine rules for geodesic triangles on the hyperbolic unit sphere H02(Association for Scientific Research, 2005) Özdemir A.; Kazaz M.In this work, we proved the sine and cosine rules for a geodesic triangle on the hyperbolic unit sphere H02 by means of timelike unit vectors. We also obtained some useful results.Item Assessment of optimum tip speed ratio of wind turbines(Association for Scientific Research, 2005) Çetin N.S.; Yurdusev M.A.; Ata R.; Özdemir A.The first thing to do in wind turbine blade design is to select tip speed ratio. Generally speaking, the speed ratio depends on the profile type used and the number of blades. Various speed ratios could be chosen for different types of profiles with different number of blades. Therefore, an optimization procedure should be applied to find the best ratio since this directly affects the energy generated from the turbine and in turn the investment made. This study presents a procedure to assess the optimum speed ratios for various profile types used in practice with various numbers of blades.Item Elliptic motion on dual hyperbolic unit sphere over(H, ∼)02(2009) Kazaz M.; Özdemir A.; Hüseyin Uǧurlu H.Planar and spherical elliptic motions had been introduced by Karger and Novák [A. Karger, J. Novák, Space Kinematics and Lie Groups, Gordon and Breach Science Publishers, New York, London, 1985]. Also, a dual spherical elliptic motion has been defined by Yapar [Z. Yapar, Spatial conchoidal and elliptic motions, Mechanism and Machine Theory 27 (1) (1992) 75-91]. In this paper, we define the elliptic motion on a dual hyperbolic unit sphere over(H, ∼)02 in the dual Lorentzian space D13 with dual signature (+, +, -) and carry the results to the Lorentzian line space IR13 by means of Study's mapping. © 2008 Elsevier Ltd. All rights reserved.Item Determination of major and minor elements in the malva sylvestris L. from turkey using ICP-OES techniques(2009) Hiçsönmez Ü.; Ereeş F.S.; Özdemir C.; Özdemir A.; Çam S.In this work, Malva sylvestris var. mauritiana (L.) leaves were collected from different points in Muradiye region of Manisa-Turkey. The leaves were dissolved by wet digestion method using a mixture of mineral acid. Concentrations of Ag, Al, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, La, Mg, Mn, Na, Ni, Pb, Sn, Sr, Sb, Si, Ti, U, Zn, and Zr in prepared solutions were determined by using inductively coupled plasma optical emission spectrometry (ICP-OES). High Ca (13,848 mg/kg) and Mg (1,936 mg/kg) concentrations were found at the leaves. Obtained values were compared with the internationally permitted (standard) values. The results of elements were analyzed statistically (analysis of variance test). For different leaf sizes, concentration factors were calculated. © 2008 Humana Press Inc.Item Evaluation of antidepressant-like effect of 2-pyrazoline derivatives(2010) Gok S.; Murat Demet M.; Özdemir A.; Turan-Zitouni G.Many studies have shown that pyrazoline derivatives have therapeutic potential as antidepressant drugs. In this study, we aimed to investigate the antidepressant-like effect of eight new 1-[(N,N-disubstituted thiocarbamoylthio)acetyl]-3-(2-thienyl)-5-aryl-2-pyrazolines that have previously been synthesized in our laboratory. Antidepressant-like activity was investigated in mouse forced swimming test (FST). Drug-induced effects on motor function were also tested by using digitized motor activity monitoring system. Shortened immobility time in FST was accepted as indicator of antidepressant-like activity. Results showed that three of eight pyrazoline compounds (1b, 1d, 1g) significantly shortened immobility time compared with control. Compound 1b was found to be more effective in FST than were clomipramine and tranylcypromine, used as reference antidepressant drugs. This compound also significantly increased horizontal motor activity, like clomipramine, compared with control mice. These results suggest that the N,N-disubstituted dithiocarbamate moiety of pyrazoline derivatives may have therapeutic antidepressant potential. © 2009 Birkhäuser Boston.Item The prevalence of microalbuminuria and relevant cardiovascular risk factors in Turkish hypertensive patients(2011) Kozan Ö.; Özcan E.E.; Sancaktar O.; Kabakci G.; Sözcüer A.H.; Kerpeten A.; Delice A.; Içli A.; Sökmen A.; Gürlek A.; Abaci A.; Bayram A.; Köşüş A.; Çamsari A.; Sakalli A.; Sert A.; Temizhan A.; Yilmaz A.; Daver A.; Aydinlar A.; Ergin A.; Kiliçoǧlu A.E.; Birdane A.; Aribaş A.; Lazoǧlu A.; Özdemir A.; Fiskeci A.; Çelik A.; Bitigen A.; Keskin A.; Yavuz A.; Akyüz A.; Karanfil A.; Ünsal A.; Sinci A.; Gülmez A.U.; Irmak A.; Vural A.; Güven A.; Ilerigelen B.; Erol B.; Polat B.; Tosun B.; Aǧçal C.; Genç C.; Kirdar C.; Rezzagil C.; Köz C.; Nazli C.; Ceyhan C.; Örem C.; Uyan C.; Türkoǧlu C.; Gaffari D.; Aytekin D.; Ural D.; Yeşilbursa D.; Aras D.; Semiz E.; Koçak E.; Atalar E.; Varol E.; Onrat E.; Şensoy E.; Acartürk E.; Akarca E.; Aygün E.; Ertaş F.S.; Koca F.; Özmen F.; Ulusoy F.V.; Özerkan F.; Inceer F.K.; Dönmez G.; Topkara G.; Daş G.; Bozkurt H.; Kültürsay H.; Tikiz H.; Akgöz H.; Kaymak H.; Öney H.; Yeǧin H.; Boǧa H.; Gök H.; Vural H.; Atasever H.; Arinç H.; Bozdemir H.; Gündüz H.; Tunar H.; Atmaca H.; Doǧru I.; Özdoǧru I.; Susal I.; Kurt I.T.; Dinçer I.; Biyik I.; Tandoǧan I.; Jordan J.; Kulan K.; Şahna K.; Öztaş K.; Dönmez K.; Övünç K.; Kaya K.; Aytemir K.; Özdemir K.; Tigen K.; Saraç L.; Sirkeci M.T.; Çakmak M.; Şahin M.; Kutlu M.; Bilge M.; Bostan M.; Melek M.; Sunay M.Ö.; Şeker M.; Güçel M.Ş.; Yazici M.; Kayikçioǧlu M.; Öç M.; Gürsürer M.; Daǧalp M.; Bilaloǧlu M.; Yalçin M.; Şerifi M.; Gökçe M.; Kiliçkap M.; Polat M.; Şan M.; Tahtasiz M.; Yilmaz M.; Etemoǧlu M.; Coşkun N.; Aran N.S.; Ata N.; Sönmez N.; Çam N.; Koylan N.; Özer N.; Keser N.; Döven O.; Tartanoǧlu O.; Ergene O.; Elönü O.H.; Onbaşili O.A.; Özbek Ö.; Pinar P.; Akdemir R.; Kargin R.; Topsakal R.; Yoldaş R.; Uçar R.; Ateşal S.; Toktaş S.; Cinsoy S.; Güleç S.; Aytekin S.; Çolak S.; Mecit S.; Sakalli S.; Sevimli S.; Topaloǧlu S.; Aydoǧdu S.; Turan S.C.; Kahraman S.; Yorganci S.; Coşkun Ş.; Ünal Ş.; Durmaz T.; Ulusoy T.; Keleş T.; Kirat T.; Gündoǧdu T.T.; Peker T.; Sümerkan U.; Aytekin V.; Koca V.; Çam V.; Gökçe V.; Gürlertop Y.; Balbay Y.; Çavuşoǧlu Y.; Erzurum Y.; Selçoki Y.; Yakar Y.; Işilak Z.; Tosun Z.; Kaplan Z.; Tartan Z.Objectives: A growing body of data illustrates the importance of microalbuminuria (MAU) as a strong predictor of cardiovascular risk in the hypertensive population. The present study was designed to define the prevalence of MAU and associated cardiovascular risk factors among Turkish hypertensive outpatients. Study design: Representing the Turkish arm of the multinational i-SEARCH study involving 1,750 sites in 26 countries around the world, a total of 1,926 hypertensive patients from different centers were included in this observational and cross-sectional survey study. Patients with reasons for a false-positive MAU test were excluded. The prevalence of MAU was assessed using a dipstick test, and patients were inquired about comorbidities, comedication, and known cardiovascular risk factors. Results: The overall prevalence of MAU was 64.7% and there was no difference between genders. Most of the patients (82.5%) had uncontrolled hypertension, 35.6% had dyslipidemia, and 35.5% had diabetes, predominantly type 2. Almost one-third of the patients (26.4%) had at least one cardiovascular-related comorbidity, with 20.3% having documented coronary artery disease (CAD). Almost all patients (96.8%) had one or more risk factors for cardiovascular disease in addition to hypertension, including family history of myocardial infarction or CAD, diabetes, dyslipidemia, lack of physical exercise, and smoking. A trend towards higher MAU values in the presence of CAD was determined. Conclusion: Microalbuminuria tests should be routinely used as a screening and monitoring tool for the assessment of subsequent cardiovascular morbidity and mortality among hypertensive patients. © 2011 Turkish Society of Cardiology.Item Some characterizations of timelike curves according to bishop frame in minkowski 3-space(2013) Kocayiǧit H.; Özdemir A.; Çetin M.; Arda B.In this study, we give some characterizations of timelike curves according to Bishop Frame in Minkowski 3-space E13 by using Laplacian operator and Levi-Civita connection.Item PLL based digital adaptive filter for detecting interharmonics(Hindawi Publishing Corporation, 2014) Özdemir A.; Taştan M.Studies on the PLL (phase locked loop) based interharmonic measurements have been considerably increased recently. The method proposed in this study is a hybrid method based on the frequency analysis. The proposed method presents solutions for the leading problems about the interharmonic measurement, such as fundamental frequency shifting, spectral leakage, and picket-fence effect, using digital PLL and adaptive notch filter. In addition, a new approach is presented to solve the multizero crossing problem encountered in the analysis of the harmonic-interharmonic. Both simulative and field data tests have been performed to verify the effectiveness of the proposed method. © 2014 Ayhan Özdemir and Mehmet Taştan.Item Cytogenetic effects of 99technetium on meristematic cells of root tips of Vicia faba L. andstatistical comparison(Taylor and Francis Ltd., 2015) Özdemir A.; Bozdağ B.; Sepet H.; Parlak Y.; Kocabaş O.; Ereeş F.S.; Özdemir C.In this study, cytogenetic effects of 99technetium (99Tc) on meristematic cells of root tips belonging to Vicia faba L. have been investigated. Seeds of the plant were prepared and kept in 99Tc standard for different time periods: 1/12, 1/4, 1/2, 1, 2, 3, 4, 5, 6 and 12 h. Seeds treated with 99Tc were sprouted and the root tips obtained were prepared for microscopic examination. Some abnormalities e.g. chromosome breaking, chromosome dispersion, bridge chromosomes, chromosome adherence and ring chromosomes were observed. Abnormalities seen for each treatment depended on the time period. The variety and number of abnormalities usually increased with increased treatment time. The results obtained were evaluated statistically. © 2015 Dipartimento di Biologia Evoluzionistica, Università di Firenze.Item Effects of shear stresses and rotary inertia on the stability and vibration of sandwich cylindrical shells with FGM core surrounded by elastic medium(Taylor and Francis Inc., 2016) Sofiyev A.H.; Hui D.; Valiyev A.A.; Kadioglu F.; Turkaslan S.; Yuan G.Q.; Kalpakci V.; Özdemir A.The vibration and stability of axially loaded sandwich cylindrical shells with the functionally graded (FG) core with and without shear stresses and rotary inertia resting Pasternak foundation are investigated. The dynamic stability is derived based on the first order shear deformation theory (FSDT) including shear stresses. The axial load and dimensionless fundamental frequency for FG sandwich shell with shear stresses and rotary inertia and resting on the Pasternak foundation. Finally, the influences of variations of FG core, elastic foundations, shear stresses and rotary inertia on the fundamental frequencies and critical axial loads are investigated. © 2016, Copyright © Taylor & Francis Group, LLC.Item A statistical comparison of anatomical features in some ornithogalum sp. Species; [Comparação Estatística das Características Anatômicas em Espécies de Ornithogalum sp](Sociedade Brasileira da Ciencia das Plantas Daninha, 2016) Özdemir A.; Kocayiǧit H.; Yetişen K.; Akyol Y.; Özdemir C.In the present study, Ornithogalum narbonense, O. montanum, O. wiedemannii, O. sigmoideum and O. lanceolatum species were compared statistically with respect to anatomical characters. Some differences were found in root, stem and leaf anatomy of the species. These differences and similarities were indicated in this study. A big metaxylem was present in all root cross sections, except for O. lanceolatum, which has three metaxylema. 2-3 layered annular type collenchyma were present in all species. Aerenchyma is present in all mesophiles. © 2016, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.Item An anatomical study of Scilla (Scilloideae) section Chionodoxa and Scilla bifolia in Turkey; [Um estudo anatômico de Chionodoxa incluída na Scilla (Scilloideae) e Scilla bifolia na Turquia](Sociedade Brasileira da Ciencia das Plantas Daninha, 2017) Yildirim H.; Yetisen K.; Özdemir A.; Özdemir C.In the present study Scilla luciliae, S. forbesii, S. sardensis, S. siehei, Scilla x allenii and S. bifolia are compared anatomically. Some differences have been found in root, scape, and leaf anatomy of the taxa, and commented. S. luciliae, S. forbesii, S. sardensis and S. siehei have a metaxylem at the center of the root, others have 3-4 number metaxylem. Vascular bundles in two row in S. luciliae and S. forbesii in a single row in S. sardensis, Scilla x allenii and S. bifolia though in three rows in S. siehei. Aerenchyma tissue is present in mesophyll of five taxa leaf except S. sardensis. The anatomical variations in the taxa have been investigated by means of numerical methods (Analysis of variance and Pearson correlation). By the analysis of the investigated taxa from 12 anatomy related characters, it has been also found that the results from numerical analysis of anatomy characters can provide additional evidences, which correspond to the anatomy for the recognition of the taxa. © 2017, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.Item Numerical comparative hairs of some Lamiaceae taxa collected from Turkey; [Comparação numérica de pelos de alguns táxons de Lamiaceae coletadas na Turquia](Sociedade Brasileira da Ciencia das Plantas Daninha, 2017) Özdemir A.; Kocabas O.In this study, glandular and aglandular hairs were examined and compared numerically in the vegatative and reproductive organs of Salvia viridis, Salvia verticillata subsp. amasiaca, Salvia virgata, Phlomis pungens var. pungen, Phlomis pungens var. hispida, Stachys cretica subsp. anatolica, Stachys cretica subsp. smyrnaea, Teucrium scordium subsp. scordioides. It has been observed that all taxa which are collected Western and Northern Anatolia have glandular hairs and aglandular hairs of various shapes, size and modes of secretion. The hairs variations in eight Lamiaceae taxa were been investigated by means of numerical methods (Analysis of variance and Pearson correlation). It was also found that the results from numerical analysis of the hairs characters can provide additional evidences for the recognition of the taxa. © 2017, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.Item Statistical comparison on numerical anatomical values of crocus L. Taxa(Pakistan Botanical Society, 2018) Özdemir A.; Akyol Y.This study aims to statistically compare the nümerical values of root and scape anatomy of 13 Crocus taxa. Anatomical variations in 13 Crocus L. taxa have been investigated by means of numerical methods (Analysis of variance and Pearson correlation). By the analysis of the investigated taxa from ten anatomy related characters, it has been determined that endodermis width, pericycle length and trache cell diameter are the best character pairs which represent the variations in them. It has been also found that the results from numerical analysis of the anatomy characters can provide additional anatomical evidences for recognition of the taxa. © 2018, Pakistan Botanical Society. All rights reserved.Item Analysis of strengthened composite beams under flexural stress(Springer, 2018) Ercan E.; Arısoy B.; Demir A.; Özdemir A.A steel-concrete composite beam is composed of a steel beam and concrete slap connected with shear connectors. Composite beams are highly efficient structural members in order to load carrying capacity because the tension component of the force pair originating from bending is carried by the steel profile and the compressive component is carried by the concrete slab in composite beams. In this study, numerical and experimental analysis of steel-concrete composite and strengthened steel-concrete composite beams is presented. In experimental study, one strengthened and one un-strengthened specimens are produced and tested in bending. Strengthening is produced applying carbon fiber reinforced polymers sheet to the lower flange of the steel beam and using steel fiber reinforced concrete in the concrete slab. Specimens are tested under four-point loading test. During the tests, load, deflection and strain values are collected by data acquisition system. In numerical study, the finite element models of the steel-concrete composite beams are generated and analyzed by Atena-GiD program. Comparison and evaluations are made in terms of strength, applicability, stiffness and energy consumption about the steel-concrete composite beams with carbon fiber reinforced polymers and steel fibered concrete for both numerical and experimental results. © Springer International Publishing AG, part of Springer Nature 2018.Item A geometric modeling of tracheal elements of the chard (Beta vulgaris) leaf; [Uma Modelagem Geométrica de Elementos Traqueais da Folha de Acelga (Beta vulgaris)](Sociedade Brasileira da Ciencia das Plantas Daninha, 2019) Arslan K.; Bulca B.; Özdemir C.; Özdemir A.; Bozdag B.In this study, we give a geometric description of the tracheal elements of the chard (Beta vulgaris var. cicla L.), which is a widespread cultivated plant in Turkey. It is used as an edible plant and its leaves are used as antidiabetic in traditional medicine plant. We have shown that the tracheal elements, which are taxonomic value of the plant, can be considered as a surface of revolution or a tubular shape along a special curve. © 2019, Sociedade Brasileira da Ciencia das Plantas Daninha. All rights reserved.Item Cytogenetic effects of c6h4 (Ch3)2 (xylene) on meristematic cells of root tips of vicia faba l. and mathematical analysis(Firenze University Press, 2020) Alaca C.; Özdemir A.; Bozdağ B.; Özdemir C.Xylene is a readily flammable and poisonous liquid with a chemical formula of C6H4 (CH3)2. It is used as raw material or auxiliary raw material in many industrial products such as dye, pencil, agricultural chemicals, rubber, fiber, glue and diaper. In this study, cytogenetic effects of xylene, on the meristematic cells of root tips of V. faba L. used as food have been investigated. For this purpose, the seeds of the plant have been treated with xylene solutions prepared in different concentrations for different time periods. Chromosomes at the root tips have been looked and the effect of xylene has been determined. The abnormalities as chromosome breaking, chromosome dispersion, bridge chromosome, chromosome adherence, ring chromosome have been observed. Abnormalities have been seen at each treatment depended on the time periods. In addition to these visible damages of xylene in the study, possible damages on chromosomes carrying genetic codes of living beings to future generations have been investigated and mathematical analyzes has been made. The results obtained have been evaluated statistically. © 2020 C. Alaca, A. Özdemir, B. Bozdağ, C. Özdemir.Item Patients eligible for modulator drugs: Data from cystic fibrosis registry of Turkey(John Wiley and Sons Inc., 2020) Çobanoğlu N.; Özçelik U.; Çakır E.; Şişmanlar Eyüboğlu T.; Pekcan S.; Cinel G.; Yalçın E.; Kiper N.; Emiralioğlu N.; Şen V.; Şen H.S.; Ercan Ö.; Çokuğraş H.; Kılınç A.A.; Al Shadfan L.M.; Yazan H.; Altıntaş D.U.; Karagöz D.; Demir E.; Kartal Öztürk G.; Bingöl A.; Başaran A.E.; Sapan N.; Çekiç Ş.; Çelebioğlu E.; Aslan A.T.; Gürsoy T.R.; Tuğcu G.; Özdemir A.; Harmancı K.; Yıldırım G.K.; Köse M.; Hangül M.; Tamay Z.; Süleyman A.; Yüksel H.; Yılmaz Ö.; Özcan G.; Topal E.; Can D.; Korkmaz Ekren P.; Çaltepe G.; Kılıç M.; Özdoğan Ş.; Doğru D.Background: A better understanding of cystic fibrosis transmembrane conductance regulator biology has led to the development of modulator drugs such as ivacaftor, lumacaftor-ivacaftor, tezacaftor-ivacaftor, and elexacaftor-tezacaftor-ivacaftor. This cross-sectional study evaluated cystic fibrosis (CF) patients eligible for modulator drugs. Methods: Data for age and genetic mutations from the Cystic Fibrosis Registry of Turkey collected in 2018 were used to find out the number of patients who are eligible for modulator therapy. Results: Of registered 1488 CF patients, genetic analysis was done for 1351. The numbers and percentages of patients and names of the drugs, that the patients are eligible for, are as follows: 122 (9.03%) for ivacaftor, 156 (11.54%) for lumacaftor-ivacaftor, 163 (11.23%) for tezacaftor-ivacaftor, and 57 (4.21%) for elexacaftor-tezacaftor-ivacaftor. Among 1351 genotyped patients total of 313 (23.16%) patients are eligible for currently licensed modulator therapies (55 patients were shared by ivacaftor and tezacaftor-ivacaftor, 108 patients were shared by lumacaftor-ivacaftor and tezacaftor-ivacaftor, and 22 patients were shared by tezacaftor-ivacaftor and elexacaftor-tezacaftor-ivacaftor groups). Conclusions: The present study shows that approximately one-fourth of the registered CF patients in Turkey are eligible for modulator drugs. As, frequent mutations that CF patients have in Turkey are different from North American and European CF patients, developing modulator drugs effective for those mutations is necessary. Furthermore, as modulator drugs are very expensive currently, financial support of the government in developing countries like Turkey is noteworthy. © 2020 Wiley Periodicals LLC