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Publication Embargo Multivalued Sakaguchi functions(2007)Let A be the class of functions f(z) of the form f(z) = z +a2z2 + ··· which are analytic in the open unit disc U = {z ∈ C||z| < 1}. In 1959 [5], K. Sakaguchi has considered the subclass of A consisting of those f(z) which satisfy Re zf (z) f(z)−f(−z) > 0, where z ∈ U. We call such a functions “Sakaguchi Functions”. Various authors have investigated this class ([4], [5], [6]). Now we consider the class of functions of the form f(z) = zα(z +a2z2 +···+anzn +···) (0 <α< 1), that are analytic and multivalued in U, we denote the class of these functions by Aα, and we consider the subclass of Aα consisting of those f(z) which satisfy Re zDα z f(z) Dα z f(z)−Dα z f(−z) > 0 (z ∈ U), where Dα z f(z) is the fractional derivative of order α of f(z). We call such a functions “Multivalued Sakaguchi Functions” and denote the class of those functions by Sα s . The aim of this paper is to investigate some properties of the class Sα s . 2000 Mathematical Subject Classification: Primary 30C45.Publication Restricted Auxiliary Differential Diagnosis of Schizophrenia and Phases of Bipolar Disorder Based on the Blood Serum Raman Spectra(Wiley, 2020) ILDIZ, GÜLCE ÖĞRÜÇ; Bayari, Sevgi; Aksoy, Umut M.; Yorguner, Neşe; Bulut, Hüseyin; Yılmaz, Sultan S.; Halimoğlu, Gökhan; Kabuk, Hayrunnisa Nur; YAVUZ, GİZEM; Fausto, RuiSchizophrenia (SZ) and bipolar disorder (BP) are severe psychiatric disorders that are characterized by an extensive spectrum of symptoms and affect approximately 2% of the world population. BP exhibits three well-distinct phases, which are classified as manic and depressive episodes and euthymic phase. These disorders are of difficult differential clinical diagnosis due to the similarity of their symptoms. Diagnostic approaches for SZ and BP are based on constructed patient interviews and subjective evaluations of clinical symptoms, and there are still no molecular-based auxiliary diagnostic tools to support the clinical diagnosis. In this study, an analytical model for auxiliary differential diagnosis of SZ and BP, based on the analysis of patients' blood serum Raman spectra, is developed, which is able to account for the different BP phases and can also differentiate SZ and BP patients from healthy individuals. The model is based on a hierarchical sequence of four two-class PLS-DA steps where the Raman spectra are theX-predictor variables. It is concluded that the full 400-3,100 cm(-1)Raman spectroscopic range is a sensitive probe for the disorders, thus working as a general spectroscopic biomarker for the illnesses. The proposed methodology is reliable, fast, cheap, essentially minimal-invasive, and might be implemented easily in the clinical environment.Publication Metadata only Molecular Mechanics Studies of Antihypertensive Val-Tyr Dipeptide(Asian Journal Of Chemistry, 11/100 Rajendra Nagar, Sector 3,, Sahibabad 201 005, Ghaziabad, India, 2010-01) Akverdieva, G. A.; Godjayev, N. M.; Doğan, N. E.; AKYÜZ, ZEKİ TANIL; AKYÜZ, SEVİM; TR10127; TR111424The spatial structure of anti hypertensive dipeptide,Valine-Tyrosine was investigated within molecular mechanics framework. It ha, been shown that the molecule has such a structural organization which does not exclude the realization of two types of conformation: folded and extended. The energy and geometrical parameters for the optimal conformations of dipeptide are obtained. The electronic characteristics for these structures were analyzed by quantum chemical calculations.Publication Restricted Molecular Structure, Vibrational Spectra, Molecular Docking, and ADMET Study of Cellulose Triacetate II(Pleiades Publishing Inc., 2020) Çelik, Sefa; Demirağ, A. Demet; Özel, Ayşen E.; AKYÜZ, SEVİMPeople have started to look for alternative sources because of the health problems created by petrochemical products used in all areas of human life and environmental problems that remain intact in nature for years. In this study, molecular structure analysis of cellulose triacetate II (CTA II) molecule, obtained from cellulose II and acetate, was carried out. There is an important relationship between the structure and activity of molecules, so it is very important to determine the geometric structure of a molecule. Therefore, using density functional theory (DFT) the most stable molecular geometries of the cellulose triacetate II monomer (C12H18O9) as well as dimer (C24H36O18), which included intermolecular H-bonding, were calculated. The analogous calculations were carried out for the (CTA-II)(2)nano-cluster (C24H34O17), which represents the local structure of CTA-II crystal, and created by binding the two most stable CTA II molecules by covalent bond. Scaled wavenumbers and potential energy distribution of the vibrational modes of CTA monomer and (CTA-II)(2)nano-cluster were computed. In order to evaluate the interaction of CTA II with theAspergillus nigercellulase enzyme,which is an important that is active in cellulose digestion and CTA II, molecular docking studies were carried out. H-binding interactions between CTA II (in monomeric, dimeric, and cluster forms) and the active site of theAspergillus nigercellulase enzyme were shown. Moreover, in silico ADMET prediction study was calculated for CTA-II monomer to predict its druglikeness properties.Publication Metadata only Bifurcations of Fibonacci generating functions(PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND, 2007-08) Özer, Mehmet; Cenys, Antanas; Hacıbekiroğlu, Gürsel; Akat, Ercüment; Valaristos, A.; Anagnostopoulos, A. N.; POLATOĞLU, YAŞAR; TR2509; TR199370In this work the dynamic behaviour of the one-dimensional family of maps F-p,F-q(x) = 1/(1 - px - qx(2)) is examined, for specific values of the control parameters p and q. Lyapunov exponents and bifurcation diagrams are numerically calculated. Consequently, a transition from periodic to chaotic regions is observed at values of p and q, where the related maps correspond to Fibonacci generating functions associated with the golden-, the silver- and the bronze mean. (c) 2006 Elsevier Ltd. All rights reserved.Publication Metadata only Structural and spectroscopic investigation on antioxidant dipeptide, L-Methionyl-L-Serine: A combined experimental and DFT study(Elsevier Science Bv, Po Box 211, 1000 AE Amsterdam, Netherlands, 2017-06-05) Kecel Gündüz, Serda; Bıçak, Bilge; Çelik, Sefa; Özel, Ayşen E.; AKYÜZ, SEVİM; 110526; 277135; 110147; 10127; 110745The focus of this study is to determine the conformational, structural and vibrational properties of Methionyl-Serine dipeptide (L-Methionyl-L-Serine, Met-Ser), a biological active molecule. To investigate their energetically preferred conformations, molecular mechanics methods were utilized to determine the optimal conformations of the 3402 different dihedral angle values of the backbone and side chains. It was found that the extended (e) backbone shape in the LB conformational range was the most stable LMethionyl-L-Serine dipeptide conformation, with 3.12 kcal/mol of energy. Density Functional Theory (DFT) was used to determine the optimized geometry, the vibrational wavenumbers and modes of the title dipeptide values, with 6-31G (d,p) and 6-311++G (d,p) basis sets. The potential energy distribution data was used to carry out the assignment of the bands. In addition, the vibrational spectra of the most stable conformer and its dimer form were determined and the obtained results were compared with the experimental IR and Raman spectra in the solid phase. To determine the presence of intramolecular charge transfer, molecular dipole moment, polarizability and hyperpolarizability, the Natural Bond Orbital (NBO), HOMO LUMO calculations, the linear polarizability (alpha) and the first order hyperpolarizability (fio) value analyses of the investigated molecule were carried out using the DFT with the B3LYP/6-31++G(d,p) basis set. This study aims to determine a relatively stable conformation of antioxidant dipeptide and to investigate the molecular geometry, molecular vibrations and hydrogen bonding interactions between monomeric and dimeric forms of Methiony-Serine dipeptide. (C) 2017 Elsevier B.V. All rights reserved.Publication Metadata only On lambda-fractional convex functions(2007) Owa, Shigeyoshi; YAVUZ, EMEL; POLATOĞLU, YAŞAR; 199370; 111202Publication Metadata only Structure and Vibrational Spectra of Benzidine(Elsevier, 2003-06-01) Akalın, Elif; AKYÜZ, SEVİM; 46357; 10127The geometry and vibrational spectrum of benzidine have been computed by ab initio calculations using the DFT/B3LYP method with 6-31+G(d,p) basis set. In the most stable geometry, the dihedral angle between the two phenyl rings was found to be around 38°. Calculated wavenumbers were scaled by a single factor 0.965 to approximately correct for vibrational anharmonicity as well as for overestimation of the force constants. Normal coordinate analysis of benzidine and some of its deuterated derivatives have also been performed in valance force field approximation in order to demonstrate the transferability of the force field of aniline. Good agreements between the two different calculation results (ab initio and force field refinement methods) and between the calculated and observed values are found.Publication Metadata only Spectroscopy and Chemometrics as Central Prospective Tools to Investigate Biologically Relevant Materials(2018) ILDIZ, GÜLCE ÖĞRÜÇ; 107326Publication Metadata only Radioisotope Excited X Ray Fluorescence Analysis of Ashes From Coal Power Plants of Turkey(Kluwer Academic Publishers, 1998-01) Başsarı, A.; AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; 10127Fifteen ash samples taken from filters and bottom products of boilers or chimneys of seven coal fired power plants in Turkey have been analysed quantitatively for some minor elements using radioisotope energy dispersive X-ray fluorescence (EDXRF). It is found that samples contain Cu, Zn, Rb, Sr, Zr, Mo, Cs, Sb, Ba, Pb, Y, La, Ce, Nd and Sm in different amounts. An ash sample taken from the electro-filter of the Ambarli, fuel oil fired-power plant was also analysed for comparison and found that it contained the smallest amount of potentially toxic elements.