Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14720/4

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0d, 1d, 2d, and 3d Soft and Hard Templates for Catalysis
(Elsevier Science Bv, 2017) Butun, Sultan; Demirci, Sahin; Yasar, Alper O.; Sagbas, Selin; Aktas, Nahit; Sahiner, Nurettin
[1,2,5]thiadiazolo[3,4-G]quinoxaline Acceptor-Based Donor-Acceptor Polymers: Effect of Strength and Size of Donors on the Band Gap
(Wiley, 2017) Gokce, Gurcan; Karabay, Baris; Cihaner, Atilla; Ozkut, Merve Icli
Electrochromic polymers based on [1,2,5]thiadiazolo[3,4-g]quinoxaline acceptor and thiophene, 3,4-ethylenedioxythiophene and 3,3-didecyl-3,4-proylenedioxythiophene donors, namely poly(6,7-diphenyl-4,9-di(thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P1), poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7-yl)-6,7-diphenyl-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P2), and poly(4-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-9-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-8-yl)-6,7-diphenyl-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P3), respectively, were electrochemically and/or chemically synthesized and characterized. Electrochemical and optical properties of the polymers were then investigated. The results, which were obtained electrochemically and optically, indicate that the polymers bearing the same acceptor and different donor units have a band gap range of 0.59-1.24 eV depending on the strength and size of the donor units and band gap determination method. A significant finding in this study was the phenomenon that when the acceptor is physically huge, the general rule that a weak donor would have a high band gap whereas a strong donor would have low band gap can be broken due to the torsional angles/steric hindrances involved with physically large donor molecules. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3483-3493
1,3-Dipolar Cycloaddition Reactions of 1-Methyl Betaine With C70-A Theoretical Study
(Amer Scientific Publishers, 2009) Turker, Lemi; Gumus, Selcuk
In the present study, the molecular orbital properties of 1,3-dipolar cycloaddition products of 1-methyl-3-oxidopyridinium betaine with C-70 have been investigated theoretically at the level of PM3 (RHF) type semi empirical quantum chemical calculations and then single point DFT calculations were performed for the energies. The betaine acts as a 4 pi-component across its 2,6-positions and certain C=C bonds of C-70 act as 2 pi-component in the 1,3-dipolar cycloadditions considered presently. Various cycloadducts are structurally possible because C-70 structure possesses 8 different 2 pi-components, therefore 8 different pairs of reaction termini exist. The results indicate that, the cycloadducts (including regioisomers) formed with [6, 6]-type double bond are more stable and less endothermic than adducts formed with the [5, 6]-type with some exceptions. Some structural, spectral and physicochemical properties of these cycloadducts have also been studied.
1800 Mhz Radio-Frequency Electromagnetic Radiation Induces Oxidative Stress in Rat Liver, Kidney and Brain Tissues
(Yuzuncu Yil Universitesi Tip Fakultesi, 2018) Berköz, M.; Arslan, B.; Yıldırım, M.; Aras, N.; Yalın, S.; Çömelekoğlu, Ü.
Radio-frequency electromagnetic radiation (RF-EMR) represents one of the environmental factor that influence animal organism to stress. In this study we determined the oxidative stress parameters from rat liver, kidney and brain tissues that were exposed to chronic 1800 MHz RF-EMR. Our study was designed in 3 groups as 9 animals in each group. These are; control, sham and RF-EMR exposed group. The control group was not exposed to any procedure; sham group was housed in the same room under the same conditions with equal time period, except that the generator was turned off. RF-EMR exposed group was subjected to 1800 MHz RF-EMR emitted from the signal generator for 2 h per day for eight weeks. All animals that completed the experimental period were sacrificed and liver, kidney and brain tissues of all rats were isolated for analyzing malondialdehyde (MDA), nitric oxide (NO) and reduced glutathione (GSH) levels and superoxide dismutase (SOD) and catalase activities. Liver, kidney and brain MDA and NO levels were higher and GSH level and SOD and catalase activities were significantly lower in RF-exposed group than control and sham groups (p<0.001). No significant difference was observed in terms of tissue MDA, GSH and NO levels and SOD and catalase activities between control and sham groups in each tissue. The results of our study shows that RF-EMR may act as an environmental stressor and cause oxidative and nitrosative damage in liver, kidney and brain tissues. © 2018, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.
2-[(2-Bromo-phen-yl)imino-meth-yl]-6-methyl-phenol
(int Union Crystallography, 2010) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
In the title compound, C14H12BrNO, is a Schiff base which adopts the phenol-imine tautomeric form in the solid state. The dihedral angle between the two aromatic rings is 34.26 (9)degrees and an intramolecular O-H center dot center dot center dot N hydrogen bond generates an S(6) ring.
2-[(E)-2-Hy-droxy-5-(trifluoro-meth-oxy)benzyl-idene-amino]-4-methyl-phenol
(int Union Crystallography, 2011) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
The title compound, C15H12F3NO3, is a Schiff base which adopts the cis-quinoid form in the solid state. The dihedral angle between the least-squares planes of the benzene rings being 3.6 (1)degrees. The F atoms of the -CF3 group are disordered over two sets of sites with refined occupancies of 0.61 (5) and 0.39 (5). An intramolecular N-H center dot center dot center dot O hydrogen bond occurs. The crystal structure is stabilized by intermolecular O-H center dot center dot center dot O hydrogen bonds.
238u and 222rn Activity Concentrations and Total Radioactivity Levels in Lake Waters
(Springer, 2013) Zorer, O. Selcuk; Sahan, T.; Ceylan, H.; Dogru, M.; Sahin, S.
The concentrations and distributions of natural radioactivity, uranium and radon in lake waters from around Van, Turkey were investigated with an aim of evaluating the environmental radioactivity. Fourteen lake waters were collected from different six lakes around Van (Turkey) to determine U-238, Rn-222 and total alpha and total beta distributions in 2009. The total alpha and total beta activities were counted by using alpha/beta counter of the multi-detector low background system (PIC-MPC-9604) and the U-238 concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2) and radon concentrations were measured with the solid state nuclear track detector technique. The activity concentrations ranging from ND to 0.039 Bq L-1 and from 0.026 to 3.728 Bq L-1 for total alpha and beta, respectively, and uranium concentrations ranging from 0.083 to 3.078 mu g L-1, and radon concentrations varying between 47.80 and 354.86 Bq m(-3) were observed in the lake waters.
3,5-Dibenzoyl
(int Union Crystallography, 2009) Sahin, Zarife Sibel; Isik, Samil; Sener, Ahmet; Tan, Meltem
In the crystal structure of the title compound, C26H27NO3, a one-dimensional network of C-H center dot center dot center dot O hydrogen bonds and pi-ring interactions is responsible for crystal stabilization. Intermolecular hydrogen bonds and C-H center dot center dot center dot pi interactions produce R-2(2)(10), R-4(4)(27) and R-4(4)(29) rings.
A 3-Db 90 Degrees Microstrip Hybrid Directional Coupler at 2.27 Ghz
(Elsevier Gmbh, 2023) Imeci, Mehmet Yusuf; Tutuncu, Bilal; Imecl, Sehabeddin Taha
A 90 degrees hybrid-coupler in the 2.27 GHz range, offering high performance despite its size of 115.64 mm2 (18.36 & lambda;g), is introduced. The main factor that distinguishes this proposed design, positively, is that the device demonstrates high fabrication tolerances due to its simplicity, and uncomplicated length dimensions. At the center of the structure are 9 metal squares, all of equal size and equidistant. It has been observed that the S-parameters remain relatively the same after increasing or decreasing the side lengths, substrate parameters, and the vertical separation dimensions. Based on these results, it has been shown that the design will provide a successful fabrication tolerance. According to the simulation results, the S-parameters are as follows: S11 = -24.01, S12 = -3.063, S13 = -3.063, and S14 = -23.47 (all in dB). The phase deviation is only 0.8 degrees. After the simulation studies, a prototype of the coupler was fabricated, and laboratory measurements were made. The simulated and measured results, have desirable agreement. Finally, a few similar studies presented in the literature are discussed with a comparative table, in terms of overall size, isolation, phase deviation, and structure complexity. Thus, the advantages of this presented structure, compared to these studies, have been revealed.
500,000 Years of Environmental History in Eastern Anatolia: the Paleovan Drilling Project
(Copernicus Gesellschaft Mbh, 2012) Litt, Thomas; Anselmetti, Flavio; Baumgarten, Henrike; Beer, Juerg; Cagatay, Namik; Cukur, Deniz; Wonik, Thomas
International Continental Scientific Drilling Program (ICDP) drilled a complete succession of the lacustrine sediment sequence deposited during the last similar to 500,000 years in Lake Van, Eastern Anatolia (Turkey). Based on a detailed seismic site survey, two sites at a water depth of up to 360 m were drilled in summer 2010, and cores were retrieved from sub-lake-floor depths of 140 m (Northern Basin) and 220 m (Ahlat Ridge). To obtain a complete sedimentary section, the two sites were multiple-cored in order to investigate the paleoclimate history of a sensitive semi-arid region between the Black, Caspian, and Mediterranean seas. Further scientific goals of the PALEOVAN project are the reconstruction of earthquake activity, as well as the temporal, spatial, and compositional evolution of volcanism as reflected in the deposition of tephra layers. The sediments host organic matter from different sources and hence composition, which will be unravelled using biomarkers. Pathways for migration of continental and mantle-derived noble gases will be analyzed in pore waters. Preliminary 40Ar/39Ar single crystal dating of tephra layers and pollen analyses suggest that the Ahlat Ridge record encompasses more than half a million years of paleoclimate and volcanic/geodynamic history, providing the longest continental record in the entire Near East to date.
8-Ohdg Levels in Patients With Allergic Rhiniti
(Yerkure Tanitim & Yayincilik Hizmetleri A S, 2011) Onbasi, Kevser; Noyan, Tevfik; Cebi, Aysegl; Kiroglu, Faruk
Objective: Respiratory allergies like allergic rhinitis and allergic asthma are more frequently observed worldwide. Chronic inflammation in the respiratory tract is observed in these diseases. Oxidative stress contributes to this inflammation in the respiratory airways. 8-OHdG is a marker of oxidative stress. The aim of our study was to investigate the 8-OHdG levels in patients with respiratory allergy. Material and Methods: 23 patients with allergy consisting of 11 men and 12 women and 23 healthy controls were enrolled to the study. Results: 8-OHdG levels were found to be higher in allergic patients in comparison to healthy controls but it was not statistically significant. Conclusion: The reason for not significantly high levels of 8-OHdG levels as a marker of oxidative stress in respiratory allergy may attribute to the factor that the inflammation in respiratory allergy is less intensive in comparison to the inflammation in atopic dermatitis.
Aas Determination of Some Trace Heavy Metals in Lake Van Water After Preconcentration by Complexation With Surface Functional Groups on Activated Carbon
(Parlar Scientific Publications (p S P), 2005) Kiliçel, F; Gökalp, F
The adsorption of some trace heavy metals on a granulated, pure and activated carbon (Riedel-de Haen, 18002) was characterized assuming that it takes place by formation of complexes with functional groups, present in the activated carbon. The concentrations were determined for each element in aqueous suspension at constant acidity. An atomic absorption spectrometric method for the determination of the trace heavy metals (Zn, Pb, Cd, Cr, Ni, Cu, Co, Bi, Mn) in Lake Van water and that of the rivers flowing into the lake has been developed after adsorption of their diethyldithiocarbamate (DEDTC) complexes on activated carbon. Complexes were adsorbed on the adsorbent at pH 3.2 +/- 0.1. Trace heavy metal ions were elueted with 20 ml of 1 M HNO3 and determined by flame atomic absorption spectrometry (FAAS). Under optimum conditions, the trace heavy metal ions in aqueous samples were concentrated about 50-fold by column treatment and recovery rates of the investigated metals were in the range 79-106%.
Ab Initio Study of Li2cata2o7 Compound: Electronic and Optical Properties for Three Phases
(Tubitak Scientific & Technological Research Council Turkey, 2019) Aycibin, Murat
The Li2CaTa2O7 compound belongs to the Ruddlesden-Popper family of layered perovskites. First principle approximation was used to investigate the electronic band structure and optical properties of the compound for three phases. Independent of the studied compound's structural type, Li2CaTa2O7 has semiconductor behavior and direct transition. In addition, the forbidden energy band gap of the compound decreases with rising temperature, as expected. Furthermore, the 3d orbital of Ca contributes to the conduction band due to the crystal field effect. Moreover, the optical response of the chosen axes of the compound to incoming electromagnetic rays varies with phase transition.
Ab-Initio Calculations of Physical Properties of Alkali Chloride Xcl (X = K, Rb and Li) Under Pressure
(Elsevier, 2015) Erdinc, Bahattin; Secuk, Mehmet Nurullah; Aycibin, Murat; Gulebagan, Sinem Erden; Dogan, Emel Kilit; Akkus, Harun
Structural properties, electronic band structure, real and imaginary parts of complex dielectric function of alkali chloride XCl (K, Rb and Li) compounds were investigated under various pressures using first principles calculations. Moreover, Gibbs free energies were also calculated at those pressures. Calculated results of the Gibbs free energy show that LiCl does not show any structural phase transition. However, structural phase transitions of KCl and RbCl occur from NaCl (B1) to CsCl (B2) at 4.5 and 1.7 GPa pressures, respectively. The electronic band gaps under pressure were also calculated. The calculated physical properties of these compounds are compared with the previous theoretical and experimental results and a good agreement was observed. (c) 2015 The Authors. Published by Elsevier B. V. This is an open access article under the CC BY-NC-ND license.
Abc, Ved, and Abc-Ved Matrix Analyses for Inventory Management in Community Pharmacies: a Case Study
(Society of Pharmaceutical Sciences of Ankara (FABAD), 2022) Dursa, E.; Arslan, M.
Inventory control methods should be used effectively in community pharmacies to determine and obtain the needs for pharmaceuticals and non-pharmaceutical products at appropriate times and with proper procedures. An effective stock control provides positive outputs in the community pharmacy’s economy, the quality of the service to be provided, and the pharmacy’s image. In this context, within the scope of this study, it aims to evaluate ABC, VED, and ABC-VED matrix analyses in terms of community pharmacies. In the study, ABC, VED, and ABC-VED matrix analyzes were applied using the inventory data of a community pharmacy serving in the city center of Van for the 2019-2020 financial year. For this purpose, firstly, annual consumption and expenditure data for each pharmacy item specified for the 2019-2020 financial year were collected. The data were then transferred to an MS Excel spreadsheet, and statistical analysis was performed using MS Excel statistical functions. As a result of ABC-VED analysis, it was determined that the drugs in the first category were of great importance for effective stock control, the drugs in the second category were of medium importance, and the drugs in the third category were of low importance. They are because the pharmacy from which the research data is taken is close to the family health center and the socioeconomic structure of the pharmacy’s environment. This categorization is thought to be appropriate. © 2022 Society of Pharmaceutical Sciences of Ankara (FABAD). All rights reserved.
Absorption Ratio of Treatment Couch and Effect on Surface and Build-Up Region Doses
(Elsevier Science Bv, 2018) Tugrul, Taylan
Aim: In this study, at different fields, energies and gantry angles, treatment couch and rails dose absorption ratio and treatment couch effect on surface and build-up region doses were examined. Background: It is assumed that radiation attenuation is minimal because the carbon fiber couches have low density and it is not generally accounted for during treatment planning. Consequently, it leads to a major dosimetric mistake. Materials and methods: Solid water phantom was used for relative dose measurement. The measurements were done using a Farmer ion chamber with 0.6 cc volume and a parallel plane ion chamber starting from surface with 1 mm depth intervals at 10 x 10 cm(2) field, SSD 100 cm. Measurements were taken for situations where the beams intersect the couch and couch rails. Results: Dose absorption ratio of carbon fiber couch obtained at gantry angle of 180 was 1.52%, 0.69%, 0.33% and 0.25% at different field sizes for 6 MV. For 15 MV, this ratio was 0.95%, 0.27%, 0.20% and 0.05%. The absorption ratio is between 3.4% and 1.22% when the beams intersect with couch rails. The couch effect increased surface dose from 14% to 70% for 6 MV and from 11.34% to 53.03% for 15 MV. Conclusions: The results showed that the carbon fiber couch increased surface dose during posterior irradiation. Therefore, the skin -sparing effect of the high energy beams was decreased. If the effect of couch is not considered, it may cause significant differences at dose which reaches the patient and may cause tissue problems such as erythema. (C) 2017 Greater Poland Cancer Centre. Published by Elsevier Sp. z o.o. All rights reserved.
Accommodation Spasm Following Tetanus Diphtheria (Td) Vaccination
(Yuzuncu Yil Universitesi Tip Fakultesi, 2020) Batur, M.; Artuç, T.; Seven, E.; Tekin, S.
Accommodation spasm is a rare condition that presents with pseudomyopia usually in children and young adults. Most of the cases are associated with emotional conditions that causes functional spasm. Sometimes, an underlying organic cause can be detected. Tetanus-diphtheria vaccine (Td) is a combined vaccine in toxoid form and performs to prevent infectious diseases caused by Clostiridium tetani and Corynebacterium diphtheriae, respectively. In this case report, we present the clinic features of a 13-year-old girl who applied with decreased vision after Td vaccination and diagnosed with isolated accommodation spasm. © 2020, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.
Accumulation of Heavy Metals on Bacillus Cereus and Pseudomonas Aeruginosa Strains Isolates From the Van Regional Soils in Turkey
(Asian Journal of Chemistry, 2007) Dostbil, Nursel
This investigation was conducted in order to determine the overall intracellular accumulation of Co2+, Cd2+ and Pb2+ on Bacillus cereus and Pseudonzonas aeruginosa which isolated from the soil samples collected from Van region. According to the results of the investigation, intracellular accumulation was observed to increase in wild type strains of B. cereus T 124 and P aeruginosa N 48 through the applications of Co2+, Cd2+ and Pb2+ (0.25, 0.5, 1, 2 and 4 mM). However, both the type of bacteria and the effect of various heavy metals caused different accumulation in two bacteria. In the three of the heavy metals put into application, B. cereus T 124 was found to have much more accumulation than P. aeruginosa N 48. The intracellular accumulation of Cd and Co metal was observed to be greater in B. cereus T 124 strain whereas the intracellular accumulation Pb2+ metal was seen to be much greater in P aeruginosa strain. The highest amount of accumulation was observed for Pb2+.
Accurately Localizing the Thyroid Tissue in Mature Cystic Teratoma of Ovary by Single-Photon Emission Computerized Tomography/Computerized Tomography
(Wolters Kluwer Medknow Publications, 2015) Demir, Yusuf; Ucler, Rifki; Alkis, Ismet; Bulut, Gulay
A 30-year-old woman with hyperthyroidism was admitted to hospital. Although increased thyroid function was found, the gland was normal in ultrasonography (USG). Additionally, thyroid iodine uptake and Tc-99m pertechnetate scintigraphy was normal. Abdomen USG detected a cystic pelvic mass in left ovary. A whole-body scan was performed 48 hours after oral ingestion of 29.6 MBq (0.8 mCi) 1-131 (iodine-131) revealed a round structure located to the left lower abdomen. Iodine uptake was detected in this cyst which was compatible with functional thyroid tissue demonstrated by SPECT/CT. The patient was underwent surgical operation and histopathology confirmed mature cystic teratoma. Accurate localization and depiction of thyroid tissue in ovary mass was provided with SPECT/CT.
Actions of Resveratrol and Serotonin Added To Stored Bloods on Lipid Peroxidation and Oxidative Dna Damage
(Yuzuncu Yil Universitesi Tip Fakultesi, 2018) Huyut, Z.; Şekeroğlu, M.R.; Alp, H.H.; Balahoroğlu, R.; Çokluk, E.
Stored blood for use in diseases such as acute blood loss, injury and anemia can be maintained for about a month. It was reported that some negative changes called "storage lesions" occur in stored bloods time dependently. In order to delay these changes, preservatives are added to stored bloods. In this study, we aimed to determine the effects of resveratrol and serotonin on oxidative DNA and mitochondrial damage and lipid peroxidation in stored blood. Blood was taken from 10 volunteers to different blood bags and each blood was separated into 3 groups (control, resveratrol and serotonin groups). Malondialdehyde (MDA), ubiquinone-10 (CoQ10) and 8-hydroxy-2-deoxyguanosine/106deoxyguanosine (8-OHdG/106dG) levels were determined at baseline and on the 7th, 14th, 21st and 28th day after addition of resveratrol and serotonin. MDA, CoQ10 and 8-OHdG/106dG levels increased over time in the control and serotonin groups (p<0.05). However, resveratrol protected against the time-dependent increase in MDA and CoQ10 values (p>0.05). MDA and CoQ10 levels were significantly lower in the resveratrol-treated group on the 21st and 28th days compared with the other groups (p<0.05). These results show that oxidation sensitivity increased time dependently in stored blood. However, the addition of resveratrol allowed the extension of the blood’s shelf life by protecting against increased lipid peroxidation and oxidized CoQ10. © 2018, Yuzuncu Yil Universitesi Tip Fakultesi. All rights reserved.

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