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Öğe Elektrookulografi (EOG) sinyalleri ile uyku evreleme(Selçuk Üniversitesi Fen Bilimleri Enstitüsü, 2017-06-22) Coşkun, Ahmet; Özşen, SeralUyku evreleme solunum ve uyku hastalıklarının teşhisi ve tedavisinde önemli bir aşamadır. Uyku evreleme günümüzde polisomnografi ile yapılmaktadır. Polisomnografi (PSG), uyku ile ilgili çeşitli bozuklukların tespiti için gece normal uyku esnasında, kafa, yüz ve belirli vücut bölgelerine konulan sensörler yardımıyla sinyallerin kaydedildiği bir testtir. Kayıtların değerlendirilmesinde uygulanması gereken ilk aşama uyku evrelerinin skorlanmasıdır. Uyku evrelerinin skorlanması için ilk standart metot Rechtschaffen and Kales (R&K) tarafından 1968 yılında geliştirilmiştir. Bu metotla bütün polisomnogram epoklara bölünür ve her bir epoğa etiket verilir. Her bir etiket uykunun temel evrelerinden birini gösterir. Bu evreler başta elektroensefalogram (EEG), elektrookülogram (EOG) ve elektromiyogram (EMG) kayıtları olmak üzere pek çok sinyalin incelenmesi ile belirlenir. 2007 yılında Amerikan Uyku Tıbbı Akademisi (AASM), uyku kayıt teknikleri ve skorlamada standardizasyon sağlayan yeni bir skorlama el kitabı yayınlamış, 2012 yılında ise revize edilerek "AASM Manual for the Scoring of Sleep-Version 2.0" adı ile yayınlanan el kitabı ile skorlama kriterleri güncellenmiştir ve bilimsel çalışmalara temel olmuştur. Bu çalışmada, diğer çalışmalardan farklı olarak sadece EOG sinyali kullanarak uyku evrelenmek istenmiştir. Necmettin Erbakan Üniversitesi Meram Tıp Fakültesi uyku laboratuvarında 15 hastadan sol göz EOG (EOGL) ve sağ göz EOG (EOGR) sinyalleri elde edilmiştir. Uyanık (wake), REM, Non-REM-1, Non-REM-2, Non-REM-3 bölgeleri belirli olan bu sinyaller üzerinden, zaman ve frekans domeninde, 36 özellik çıkarılmış ve sınıflandırmaya tabi tutulmuştur. Sinyaller uyanık (wake), hafif uyku (REM + Non-REM-1), derin uyku (Non-REM-2+Non-REM-3) olarak gruplanmıştır. Sınıflandırma algoritması olarak Naive Bayes, C4.5 karar ağacı (J48 decision tree), K-en yakın komşu algoritması (K-nearest neighbours classifier), YSA (Multilayer Perceptron), Random Forest algoritmaları kullanılmış olup Temel Bileşen Analizi (TBA) ile özellik seçimi yapılmıştır. Çalışmanın sonucunda en yüksek sınıflandırma doğruluğunun Random Forest algoritması olduğu ve %80.15 doğruluk ile sınıflandırdığı görülmüştür.Öğe Immobilization of oxime derivative on silica gel for the preparation of new adsorbent(ELSEVIER, 2009) Gübbük, İlkay Hilal; Hatay, İmren; Coşkun, Ahmet; Ersöz, MustafaA new silica gel compound modified 4,4'-oxy-bis(chlorophenylglyoxime) (CPGO) was synthesized and characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. The sorption capacity of such a matrix towards Co(II), Ni(II) and Cu(II) from aqueous solutions was studied. The optimum pH values for the separation of these divalent cations on the sorbent were 5.0, 6.0 and 6.0 for Cu, Co and Ni, respectively. The process of metal separation was followed by batch method, and fitted to a Langmuir and Freundlich sorption isotherms. The maximum sorption capacities (0.055, 0.042, and 0.034 mmol g(-1)) were found from the Langmuir equation and the enthalpies of binding were 44.96, 71.63, and 68.14 kJ mol(-1) for Cu, Co and Ni. respectively. The other thermodynamic parameters calculated from the adsorption results were used to explain the mechanism of the adsorption. For example, the Gibbs free energies of binding agree with the spontaneity of the proposed reaction between cations and basic centers. (C) 2009 Elsevier B.V. All rights reservedÖğe New copper(II) and nickel(II) complexes of 4-morpholinoaceto-phenone thiosemicarbazone: Structural, electrochemical and antimicrobial studies(WILEY-V C H VERLAG GMBH, 2007) Bingöl, Haluk; Coşkun, Ahmet; Akgemci, Emine Güler; Kaya, Baştürk; Atalay, Tevfik4-Morpholinoacetophenone thiosemicarbazone, MAPT, and its nickel(II) and copper(II) complexes have been prepared and characterized by elemental analysis, magnetic susceptibility, spectral methods (FT-IR, H-1 NMR) and cyclic voltammetry. Electrochemical behaviors of the complexes have been studied by cyclic voltammetry in DMF media showing metal centered reduction processes for both of them. The redox properties, nature of the electrode processes and the stability of the complexes were discussed. [Cu(MAPT)(2)]Cl-2 complex shows Cu(II)/Cu(I) couple and quasi-reversible wave associated with the Cu(III)/Cu(II) process. The reduction/oxidation potential values depend on the structures of complexes. Also, the antimicrobial activities of these complexes were determined against S. aureus, E. coli and B. subtilis.Öğe A Novel Benzothiazole Based Azocalix[4]arene as a Highly Selective Chromogenic Chemosensor for Hg2+ İon: A Rapid Test Application in Aqueous Environment(Elsevier Science Bv, 2010) Bingöl, Haluk; Kocabaş, Erdal; Zor, Erhan; Coşkun, AhmetA novel calix[4]arene derivative containing benzothiazole azo groups at the upper rim was synthesized as chromogenic chemosensor, and its binding and sensing properties with heavy metal ions (Pb2+, Hg2+, Ni2+, Cd2+, Cu2+, Zn2+, Co2+, Fe2+, Mn2+, Cr3+, Ag+) were investigated by UV-vis spectroscopy and voltammetric techniques. The results of spectroscopic and voltammetric experiments showed that the chromogenic chemosensor has high selectivity towards Hg2+ ion over the other heavy metal ions. Moreover, it was shown that the interaction between Hg2+ and the chromogenic chemosensor occurs by means of the benzothiazole azo groups at the upper rim by using differential pulse voltammetry. The stoichiometric ratio and the association constant were determined as 1:1 and (6.1 +/- 0.3) x 10(5) L mol(-1) for the complex between Hg2+ and the ionophore. Furthermore, we prepared a rapid test kit for early detection of Hg2+ in aqueous environment in the concentration range of 1 x 10(-4) to 1 x 10(-2) M.Öğe A Rapid and High-Yielding Synthesis of Thiazoles and Aminothiazoles Using Tetrabutylammonium Salts(Pergamon-Elsevier Science Ltd, 2010) Kocabaş, Erdal; Sarıgüney, Ahmet Burak; Coşkun, AhmetA convenient method for the synthesis of thiazoles and aminothiazoles by treatment of phenacyl bromides with thioamides/thiourea in the presence of tetra butylammonium hexafluorophosphate (Bu4NPF6) at room temperature was developed. The products having high yields were formed rapidly (within 15 min). The method is simple, rapid and practical, generating thiazole derivatives in excellent isolated yields. The structures of the newly synthesized products were identified by FT-IR, H-1 NMR, C-13 NMR spectroscopy and elemental analysis data.Öğe Selective sodium ion transfer across a water/1,2-dichloroethane micro-interface by a calix[4]arene derivative(ELSEVIER SCIENCE SA, 2011) Kaykal, Ferhat; Kocabaş, Erdal; Bingöl, Haluk; Akgemci, Emine Güler; Coşkun, AhmetThe transfer of alkali and alkaline-earth metal ions facilitated by a calix[4]arene derivative, 25,27-di [(2-ethoxy)benzaldehyde]-26,28-dihydroxy-5,11,17,23-tetra(tert-butyl) calix[4]arene (DBC4), across a water/1,2-dichloroethane (1,2-DCE) micro-interface supported at the tip of a micropipette was investigated. The well-defined voltammetric behavior was obtained only for Na+ ion among the used metal ions by using the electrochemical methods. The measurements were performed when the bulk concentration of Na+ ion in the aqueous phase is much higher than that of DBC4 in the organic phase, and vice versa. The diffusion coefficient of DBC4 in the DCE phase was calculated to be equal to (4.2 +/- 0.2) x 10(-6) cm(2) s(-1). The logarithm of the association constant of DBC4-Na+ complex having 1:1 stoichiometry in 1,2-DCE was determined as 3.99. The differential pulse voltammetry was used for amperometric detection of Na+ ion in chloride medium. The results show that DBC4 can be used for many analytical applications such as ion recognition and fabrication of electrochemical sensor for Na+ ion because of its good selectivity. (C) 2011 Elsevier B.V. All rights reserved.Öğe Selective transport and removal of Cr(VI) through polymer inclusion membrane containing 5-(4-phenoxyphenyl)-6H-1,3,4-thiadiazin-2-amine as a carrier(ELSEVIER, 2011) Saf, Ahmet O.; Alpaydın, Sabri; Coşkun, Ahmet; Ersöz, MustafaIn this study, the transport of Cr(VI) ions through polymer inclusion membrane (PIM) containing 5(4-phenoxyphenyl)-6H-1,3,4-thiadiazin-2-amine (FFAT) firstly used as a carrier from acidic aqueous solution into CH3COONH4 aqueous solution was presented. PIM was characterized by AFM. FTIR techniques and contact angle measurements. The efficiency of Cr(VI) transport through PIM was optimized as a function of the donor and acceptor phase compositions as well as the membrane composition. The transport efficiency of Cr(VI) was obtained as 89.83% after 10 h under the optimized conditions. Also, a selective removal experiment of Cr(VI) ions from electroplating wastewater including Cr(VI), Cu(II), Ni(II), AI(III) and Fe(III) was performed and the selective removal of Cr(VI) was successfully carried out with the recovery factor of 43.29%. This novel PIM containing FFAT as a carrier exhibited an excellent Cr(VI) transport characteristic and a high selectivity for Cr(VI) ions among other heavy metal ions. It was observed that FFAT can be used as a carrier in PIMs for transport of Cr(VI). (C) 2011 Elsevier B.V. All rights reserved.Öğe Synthesis and electrochemical properties of a novel calix[4]arene derivative for facilitated transfer of alkali metal ions across water/1,2-dichloroethane micro-interface(TAYLOR & FRANCIS LTD, 2011) Kaykal, Ferhat; Bingöl, Haluk; Sarıgüney, Ahmet B.; Coşkun, Ahmet; Akgemci, Emine GülerThe alkali metal ion transfers facilitated by a novel calix[4]arene derivative (OPEC) across the water/1,2-dichloroethane (1,2-DCE) micro-interface supported at the tip of a micropipette were presented. The well-defined voltammetric behaviours except Cs+ was obtained by cyclic voltammetry and differential pulse voltammetry. The bulk concentration of metal ions was much higher than that of OPEC in the performed measurements. The diffusion coefficient of OPEC in the 1,2-DCE phase was calculated as 5.18 +/- 0.70 x 10(-6) cm(2) s(-1). On the basis of the changes of the half-wave transfer potentials, the logarithms of the association constants having 1:1 ionophore-ion complex stoichiometry for Li+, Na+, K+ and Rb+ in 1,2-DCE were determined as 4.80, 4.62, 4.98 and 5.32, respectively. The facilitated ion transfers were also evaluated by the Randles equivalent circuit used for ac-impedance data analysis.Öğe Synthesis of Novel Tripodal-Benzimidazole From 2,4,6-Tris(P-Formylphenoxy)-1,3,5-Triazine: Structural, Electrochemical and Antimicrobial Studies(ELSEVIER SCIENCE BV, 2010) Koç, Ziya Erdem; Bingöl, Haluk; Saf, Ahmet O.; Torlak, Emrah; Coşkun, AhmetFour new tripodal-benzimidazole derivatives were synthesized by Schiff base reaction between 2,4,6-tris(p-formylphenoxy)-1,3,5-triazine (TRIPOD) and different diamine derivatives. The structures of the obtained compounds were identified by FT-IR, (1)H NMR, (13)C NMR and UV-vis spectral data, thermal analysis and elemental analysis. Electrochemical behaviors of the compounds were studied by cyclic voltammetry in DMF including 0.1 M [NBu(4)] [PF(6)]. The voltammograms showed peaks having similar characteristics except tripodal-benzimidazole including -NO(2) derivative. In addition, their antimicrobial activities were evaluated by using the standard disk diffusion method in dimethylformamide media. The activities were determined against 4 bacteria cultures by comparing to those of gentamycin.Öğe The synthesis of substituted 4,4'-thiobis (aminophenylglyoxime) and their polymeric metal complexes with Cu(II), Ni(II) and Co(II) salts(2004) Coşkun, Ahmet; Karataş, İbrahim4,4'-Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (H_2L) and glyoxime (H_4L) derivatives were also prepared. Then 3 new substituted 4,4'-thiobis(aminophen-ylglyoxime) (H_4L{1-}3) were synthesized from 4,4'-thiobis(chlorophenylglyoxime) and the corresponding amines. The Ni(II), Cu(II) and Co(II) complexes of these ligands were prepared. The structures of these ligands and their complexes were identifed by FT-IR, 1H NMR and ICP-AES spectral data, elemental analyses and magnetic measurements.Öğe Synthesis, characterization and electrochemical investigation of a novel vic-dioxime ligand and its some transition metal complexes(SPRINGER, 2008) Coşkun, Ahmet; Yılmaz, Funda; Akgemci, Emine Güler4-(Chloroacetyl)diphenyl ether was synthesized from chloroacetyl chloride and diphenyl ether in the presence of AlCl3 as catalyst in a Friedel-Crafts reaction. Then, its keto oxime and dioxime derivatives were prepared. 4-phenoxy-(N-4-chlorophenylamino)phenylglyoxime (H2L) was synthesized from 4-(phenoxy)chlorophenylglyoxime and 4-chloroaniline. Ni(II), Co(II) and Cu(II) complexes of H2L were obtained. The mononuclear Ni(II), Co(II) and Cu(II) complexes of H2L have a metal-ligand ratio of 1:2 and the ligand coordinates through the two N atoms, as do most of the vic-dioximes. The structure of the ligand was identified by FT-IR, H-1 NMR, C-13 NMR, C-13 NMR (APT) spectroscopy and elemental analysis data. The structures of the complexes were characterized on the basis of FT-IR, ICP-AES, UV-Vis, elemental analysis, magnetic susceptibility measurements, and cyclic voltammetry. The electrochemical measurements were obtained by using cyclic voltammetry in DMF solution at room temperature. The electrochemical behaviors of H2L and its complexes showed that the redox process of H2L has one irreversible oxidation wave, whereas the redox processes of the complexes have both oxidation and reduction waves with metal centered.Öğe Türkiye'deki Psikiyatristlerin Hasta-Hekim İlişkisinde Gizlilik Hakkında Görüş ve Tutumları(2002) Coşkun, Ahmet; Savaş, Haluk A.; Hayran, Osman; Gergerlioğlu, H. Serdar; Arkonaç, OğuzHasta-hekim ilişkisinde "gizlilik" (confidentiality) çağdaş etik literatüründe çok tartışılan konulardandır. Özellikle iletişim ve bilişim teknolojilerindeki gelişmelerle birlikte psikiyatri pratiğinde de gizlilikle ilgili olarak etik sorunlar ortaya çıkmaktadır. 67 sorudan oluşan yarı-yapılandırılmış bir anket formuyla psikiyatristlerin sosyo-demografik verileri ve teorik, felsefi, psikiyatrik yönelimleri ve bazı etik ikilemler hakkında görüş ve tutumları sorulmuş ve toplam 12 sorunun cevapları ele alınmış olup diğer sorular başka incelemelerin konusu yapılacaktır. Ülkemizdeki psikiyatristlerin eğitim amacıyla hasta hekim ilişkisinin video gösterimini % 77, ensest vakasının adli birimlere bildirimini % 54, canlı yayında TV veya radyoda hasta hekim ilişkisinin gerçekleşmesini % 27, HIV () hastanın durumunu eşine bildirmeyi % 63 oranında onayladıkları saptanmıştır. Hasta-hekim ilişkisinde gizlilik konusundaki yaklaşımlarında psikiyatristlerin bazı sosyo-demografık ve teorik, mesleki yönelim farklılıklarına göre, istatistiksel derecede anlamlı farklar gösterdikleri bulunmuştur. Hekimler tanımlanan örnek olaylarda kamu yararı olduğu durumlarda gizliliğin sınırlarını esnek tutmaktadırlar. Fakat kitle iletişim araçlarında hastaların gizliliğinin zarar görebileceği durumları onaylamamaktadırlar.
