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Altundag A.,Istanbul Surgery Hospital | Cayonu M.,Amasya University
Current Pharmaceutical Design | Year: 2016

Background. Cancer and its treatment therapies, such as chemotherapy and radiotherapy, have negative effects on taste and smell functions. It is easy to explain smell and taste dysfunctions when a cancer involves the peripheric end organs or neurologic pathways of smell and taste. However, it is difficult to understand how distortion in sensory perception develops as cancer progresses and cancer therapies are applied, because few studies on this subject have described heterogeneous oncological patient populations who are receiving different treatment regimens. Methods. A literature review was performed about the chemical senses of the patients with various cancer types, and also about the possible mechanisms of taste and smell dysfunctions in cancer patients. Results. Chemotherapy and radiotherapy may cause taste and smell alterations by destroying taste and olfactory receptor cells, creating alterations on the surfaces of cells and receptors as well as interrupting neural coding. The prevalence of taste dysfunctions in cancer patients has been reported to be up to 77%. Unlike taste dysfunction, diminished sensitivity of smell in cancer patients is described infrequently and the available literature contains some conflicting results for smell dysfunction in cancer patients. Conclusion. Further studies are needed on the loss of appetite in cancer patients, and specific treatments should be identified according to the pathologic mechanism responsible for anorexia and particularly for taste and smell dysfunctions. Because sufficient nutrition and energy intake can help patients overcome the cancer and its treatment-related complications. © 2016 Bentham Science Publishers.


Sezgin Sezer A.,Amasya University
Knowledge-Based Systems | Year: 2012

In this paper, by defining soft intersection-union product, we make a new approach to the classical ring theory via soft set theory, with the concept of soft union rings, ideals and bi-ideals. Moreover, we characterize regular, regular duo, intra-regular and strongly regular rings by soft union rings and ideals. © 2012 Elsevier B.V. All rights reserved.


Tanak H.,Amasya University
International Journal of Quantum Chemistry | Year: 2012

Density functional calculations of the structure, molecular electrostatic potential, and thermodynamic functions have been performed at B3LYP/6-31G(d) level of theory for the title compound of 2-[(2,4-dimethylphenyl)iminomethyl]-3, 5-dimethoxyphenol (I). To investigate the tautomeric stability, optimization calculations at B3LYP/6-31G(d) level were performed for the enol and keto forms of I. Calculated results reveal that the enol form of I is more stable than its keto form. The predicted nonlinear optical properties of I are much greater than ones of urea. The changes of thermodynamic properties for the formation of the title compound with the temperature ranging from 200 to 500 K have been obtained using the statistical thermodynamic method. At 298.15 K, the change of Gibbs free energy for the formation reaction of I is 32.973 kJ/mol. The title compound can not be spontaneously produced from the isolated monomers at room temperature. The tautomeric equilibrium constant is computed as 0.868 at 298.15 K for enol-imineâketo-amine tautomerization of I. In addition, natural bond orbital analysis of I was performed using the B3LYP/6-31G(d) method. © 2011 Wiley Periodicals, Inc.


Vural H.,Amasya University
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2015

(Chemical Equation Presented) A new chelidamate complex of Cd (II) ion, [Cd2(dpa)2(chel)2]·2[Cd(dpa)(chel)]·6H2O [(chel: chelidamate or 4-hydroxypyridine-2,6-dicarboxylate, dpa: di (2-picolyl)amine)] was synthesized and characterized by spectroscopic (UV-Vis and FT-IR spectroscopy) and structural (single-crystal X-ray diffraction) methods. Quantum chemical calculations were carried out by using Hartree Fock (HF) and Density Functional Theory (DFT)/B3LYP methods Stuttgart/Dresden (SDD) basis set. The asymmetric unit of the title compound contains two symmetry unrelated monomeric units, one dimeric unit and six water molecules of crystallization. The geometries around the Cd (II) metal centers in the units can be described as distorted octahedral for the monomeric units and distorted monocapped trigonal prism for the dimeric unit. The electronic structure of the complex was calculated using time dependent DFT (TD-DFT) method with polarizable continuum model (PCM). Molecular stability and bond strength were investigated by applying natural bond orbital analysis (NBO). The computed frequencies were compared with experimental frequencies. © 2014 Elsevier B.V. All rights reserved.


Mavi B.,Amasya University
Annals of Nuclear Energy | Year: 2012

The linear attenuation coefficients of γ-rays for some granite samples have been measured at 662, 1773 and 1332 keV. The γ-rays have been obtained from 137Cs and 60Co sources respectively and the measurement have been performed using a gamma spectrometer which contains 3" × 3" NaI(Tl) detector connected to 16384 channel Multi-Channel-Analyser (MCA). © 2012 Elsevier Ltd. All rights reserved.


Gok A.,Amasya University
Measurement: Journal of the International Measurement Confederation | Year: 2015

Surface roughness affects the strength of parts during contact and working performance. Therefore, generating optimum surface roughness values are crucial to obtain high productivity in the manufacturing of turning geometries. This study presents a new method of choosing optimal cutting parameters. The first aim of this study is to investigate turning of ductile iron using fuzzy TOPSIS and grey relational analysis of optimum cutting parameter values. The second aim of the study is to determine using response surface analysis of mathematical model depending on cutting parameters of average surface roughness, maximum roughness, and main cutting force and feed force in turning. The adequacy of the developed mathematical model is proved by ANOVA. The results indicate that the depth of cut was the dominant property on the surface roughness and cutting forces. © 2015 Elsevier Ltd. All rights reserved.


Deltamethrin and thiachloprid are an α-cyano class pyrethroid and neonicotinoid insecticide, respectively. Recently, a pesticide combining deltamethrin and thiacloprid has also been released. In the present study, the acute and subacute toxic effects of deltamethrin, thiachlopride, and a combination of these insecticides, on the lymphoid organs (spleen, thymus and bone marrow), polymorphonuclear leukocytes (PMNs) and plasma of rats, were determined to better understand mammalian antioxidant-oxidant and inflammatory system responses. For this purpose, rats were treated orally with different doses of thiacloprid (single acute dose of 112.5. mg/kg); subacute dose of 22.5. mg/kg/day for 30. days; deltamethrin (single acute dose of 15. mg/kg); subacute dose (3. mg/kg/day for 30. days), or a combination of these pesticides. Results were compared with those from a comparable dosing regimen with the known immunosuppressive drug cyclophosphamide. Pesticide treatments caused significant changes in the levels of liver and kidney injury markers. Antioxidant enzyme (catalase and glutathione peroxidase), glutathione and plasma antioxidant levels decreased but lipid peroxidation increased in all lymphoid organs and the plasma. Glutathione- S-transferase and especially DT-diaphorase activity, decreased after thiacloprid treatment. Myeloperoxidase activity, carbonyl content, lipid peroxidation and total nitrite levels increased in PMNs and plasma. When evaluated as a whole, the oxidative and inflammatory stresses seen in the pesticide combination groups were not much more pronounced than in the groups treated with a single pesticide. In terms of the evaluated biochemical parameters, the pesticides showed similar effects to cyclophosphamide. © 2011 Elsevier Inc.


Density functional calculations of the structure, vibrational spectra, molecular electrostatic potential and thermodynamic functions have been performed at the B3LYP/6-311++G(d,p) level of theory for the Schiff base compound 2-[(2,4-Dimethylphenyl)iminomethyl]-6-methylphenol. Experimental and theoretical Fourier transform infrared (FT-IR) studies of the title compound show the preference of enol form, as supported by X-ray analysis results. Using the time-dependent density functional theory (TD-DFT) method, electronic absorption spectra of the compound have been predicted and a good agreement is determined with the experimental ones. To investigate the tautomeric stability, optimisation calculations at B3LYP/6-311++G(d,p) level were performed for the enol and keto forms of the title compound. Calculated results show that its enol form is more stable than that of the keto form. The predicted non-linear optical properties of the title compound are much greater than those of urea. The changes in thermodynamic properties for the formation of the title compound with the temperature ranging from 200 K to 500 K have been obtained using the statistical thermodynamic method. At 298.15 K the change of Gibbs free energy for the formation reaction of the title compound is 37.03 kJ/mol. The title compound cannot be spontaneously produced from the isolated monomers at room temperature. The tautomeric equilibrium constant is also computed as 1.23×10-3 at 298.15 K for enol ↔ keto tautomerisation of the title compound. © 2013 Taylor & Francis.


Sezgin A.,Amasya University | Atagun A.O.,Bozok University
Computers and Mathematics with Applications | Year: 2011

Soft set theory, proposed by Molodtsov, has been regarded as an effective mathematical tool to deal with uncertainties. In this paper, first we prove that certain De Morgan's law hold in soft set theory with respect to different operations on soft sets. Then, we discuss the basic properties of operations on soft sets such as intersection, extended intersection, restricted union and restricted difference. Moreover, we illustrate their interconnections between each other. Also we define the notion of restricted symmetric difference of soft sets and investigate its properties. The main purpose of this paper is to extend the theoretical aspect of operations on soft sets. © 2010 Elsevier Ltd. All rights reserved.


Atagun A.O.,Bozok University | Sezgin A.,Amasya University
Computers and Mathematics with Applications | Year: 2011

Soft set theory, proposed by Molodtsov, has been regarded as an effective mathematical tool to deal with uncertainties. In this paper, we introduce and study soft subrings and soft ideals of a ring by using Molodtsov's definition of the soft sets. Moreover, we introduce soft subfields of a field and soft submodule of a left R-module. Some related properties about soft substructures of rings, fields and modules are investigated and illustrated by many examples. © 2010 Elsevier Ltd. All rights reserved.

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