Van Yüzüncü Yıl Üniversitesi

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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.
12 Years After Roboski: Prolonged Grief and Posttraumatic Effects
(American Psychological Association, 2025) Ayhan, C.H.; Tanhan, F.; Yağan, F.; Avcı Erdal, N.; Öztürk, G.; Bedir, G.; Aslangiri, S.
Objective: The Roboski massacre, which took place on December 28, 2011, is remembered as a major tragedy resulting from a cross-border operation by the Turkish Air Force that led to the loss of 34 civilians, including 19 children. This event not only caused significant physical losses but also left a profound psychological, social, and political impact on those affected. An enhanced comprehension of prolonged grief disorder’s development can assist professionals in identifying bereaved individuals requiring assistance and augment the efficacy of treatments. The aim of this study is to examine the relationship between the grief process and symptoms of posttraumatic stress, perceived discrimination, and political trust within the framework of the theory of prolonged grief in a sample of the bereaved family members who lost their relatives in the Roboski massacre almost 12 years postloss. Method: In total, 88 Kurdish individuals (Mage = 37.13, SD = 16.4; 53.4% males) who had lost their close relatives in the Roboski incident in 2011 participated in this study. The Prolonged Grief Scale, the Posttraumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, the Perceived Discrimination Scale, and the Political Trust Scale were used to collect data. Results: The findings of the study revealed that, even approximately 12 years after the Roboski massacre, a significant portion of the participants continue to experience symptoms of prolonged grief and posttraumatic stress reactions. There was a positive correlation between prolonged grief symptoms and posttraumatic stress reactions (r =.71) as well as perceived discrimination (r =.53). It was also found that the subdimensions of posttraumatic stress, namely “reexperiencing” (β =.19, p <.05), “negative cognitive alterations” (β =.39, p <.05), and “perceived collective discrimination” (β =.11, p <.05), were significant predictors of prolonged grief. Conclusions: Our findings revealed that professionals should focus on identifying bereaved people who experience prolonged grief after a traumatic loss. Targeting these symptoms may alleviate the exacerbation of persistent grief reactions several years after a traumatic loss.Our findings suggest that addressing prolonged grief disorder following a massacre requires a multifaceted approach that includes early intervention, tailored therapeutic strategies, and robust social support systems. By integrating these elements, mental health professionals can significantly improve outcomes for those affected by traumatic loss, facilitating a path toward recovery and resilience. © 2025 American Psychological Association
18f Fdg Pet/Ct in a Child With Gliomatosis Cerebri
(Elsevier Doyma Sl, 2013) Surucu, E.; Mutafoglu, K.; Ince, D.; Cakmakci, H.; Demiral, A.; Polack, B. Degirmenci
A 2,2-Dichloropropionic Acid-Degrading Novel Pseudomonas Fluorescence Strain Fatsa001: Isolation, Identification, and Characterization
(Taylor & Francis inc, 2025) Meral, Ulku Binboga; Edbeib, Mohamed Faraj; Kirkinci, Suleyman Faruk; Aksoy, Hasan Murat; Akman, Ayhan; Wahab, Roswanira Abdul; Kaya, Yilmaz
There are mounting concerns over the high concentrations of non-biogenic, toxic halogenated organic compounds being liberated into the ecosystem. Therefore, this study's isolation of a novel bacterium from a contaminated stream in Fatsa, Ordu, Turkey, adept in degrading 2,2-dichloropropionic (of 2,2-DCP) is a welcome endeavor. The ability of the bacterial isolate to utilize 2,2-DCP as the sole carbon and energy source was discovered when the bacterium was observed to grow well on liquid minimal media containing 20 mM of 2,2-DCP, showing a doubling time of 14.2 h. The following genetic and biochemical characterizations revealed that the 16S rRNA sequence of the fatsa001strain is identical (99%) to Pseudomonas fluorescence, after which the sequence was deposited in the NCBI GenBank as Pseudomonas sp. strain fatsa001 (MN098848). The halogen-degrading ability of the P. fluorescens fatsa001 bacterium was again confirmed by the PCR data, which showed the presence of a conserved group of amino acids from the group I dehalogenase gene. It worth mentioning here that this is the first report on a P. fluorescence bacterial strain with the ability to degrade toxic 2,2-DCP. The detoxification ability of this bacterium envisages its practicality as an in situ environmental bioremediation agent.
2,6-Bis((e) and Its Metal(Ii) Complexes: Synthesis, Spectroscopy, Biological Activity, and Photoluminescence Features
(Wiley-v C H verlag Gmbh, 2013) Gulcan, Mehmet; Zengin, Huseyin; Celebi, Metin; Sonmez, Mehmet; Berber, Ismet
The preparation, characterization, magnetic measurements, antimicrobial activity, and photoluminescence properties of a number of metal complexes with a Schiff base ligand derived from 2, 6-diformyl-4-methylphenol and 1-amino-5-benzoyl-4-phenyl-1H-pyrimidine-2-thione are reported herein. UV/Vis spectra and magnetic measurements infer square planar stereochemistry for Pd-II and Pt-II complexes, and octahedral arrangement for the other metal complexes. The compounds results in intense emission (where (max) = 402 nm) upon irradiation by UV light. The photoluminescence quantum yields and long excited-state lifetimes of the ligand and its complexes were calculated as 42% and 3.94 ns, respectively. The photoluminescence intensities and quantum yields of metal complexes changed upon complexation with various metal ions. The ligand and its complexes are of interest as organic emitting materials for electroluminescent devices. The complexes were additionally evaluated for in vitro the antimicrobial activity against bacterial and fungal strains. While Cu-II, Co-II, and Pt-II complexes have good antifungal efficiency against yeast (MICs, 80 gmL(-1)), only the complex [Cu(L)(AcO)]4H(2)O had effective and selective antimicrobial activity against all tested microorganisms with MIC values in the range of 40-80 gmL(-1), except for E. coli ATCC 4230. This study suggests that the complex [Cu(L)(AcO)]4H(2)O may be a new potential antimicrobial substance towards bacteria and fungi.
The 2011 Van Earthquake S and Resilience in the Urban Population
(Istanbul Univ, Fac Letters, dept Geography, 2022) Choi, Jae hun; Alaeddiginoglu, Faruk
About a decade after the 2011 earthquakes, can people say that the city of Van has recovered now? This study purposes to answer this question by presenting a method for measuring the shock and process of recovering from an earthquake in terms of resilience and to provide objective results indicating whether or not Van has recovered from the shock of the 2011 earthquakes using this method. This study presents a method for measuring resilience in terms of population and local economic resilience. This study proposes the following five variables for measuring resilience in terms of population: decline year, drop (the degree of decline than expected), rebound (the velocity of recovery from decline), resilience index, and slope change (of the population regression equation). By synthesizing the resilience measurement results up to the end of 2019, the population growth rate of the whole city has yet to return to pre-earthquake levels. When measuring the resilience indicators at the neighborhood level, the neighborhoods that Housing Development Administration of Turkiye (TOKI) had built and the neighborhoods around the city center show high resilience. The resilience indicators for neighborhoods near TOKI were low. The conclusion is that appropriate measures have not been taken from the perspective of the entire city of Van to overcome the effects of the 2011 earthquakes.
The 23 October 2011 Mw7.0 Van (Eastern Turkey) Earthquake: Interpretations of Recorded Strong Ground Motions and Post-Earthquake Conditions of Nearby Structures
(Earthquake Engineering Research Institute, 2014) Akansel, V.; Ameri, G.; Askan, A.; Caner, A.; Erdil, B.; Kale, O.; Okuyucu, D.
A major thrust-fault earthquake of MW = 7.0 occurred on 23 October 2011 at 10:41:21 UTC in the eastern Anatolian region of Turkey, severely affecting the nearby towns of Van and Erciş. In this study, a few strong-motion records from the epicentral area are analyzed in order to investigate the characteristics of the ground motions. Also reported are the post-earthquake field observations for various types of structures, such as buildings, bridges, historical structures, tunnels, and dams within the vicinity of the fault plane. The spatial distribution of damage indicates a noticeable hanging-wall effect. The special-type structures are observed to experience far less damage, as opposed to the building structures in the region pointing to the need for strict compliance to seismic building code and the corresponding construction requirements.© 2014, Earthquake Engineering Research Institute.
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.
238u and Total Radioactivity in Drinking Waters in Van Province, Turkey
(Taylor and Francis Ltd., 2014) Selçuk Zorer, Ö.; Daǧ, B.
As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of total radioactivity and natural uranium have been analysed in drinking water samples. A survey to study natural radioactivity in drinking waters was carried out in the Van province, East Turkey. Twenty-three samples of drinking water were collected in the Van province and analysed for total α, total β and 238U activity. The total α and total β activities were counted by using the α/β counter of the multi-detector low background system (PIC MPC-9604), and the 238U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2). The samples were categorised according to origin: tap, spring or mineral supply. The activity concentrations for total α were found to range from 0.002 to 0.030 Bq L-1 and for total β from 0.023 to 1.351 Bq L-1. Uranium concentrations ranging from 0.562 to 14.710 μg L-1 were observed in drinking waters. Following the World Health Organisation rules, all investigated waters can be used as drinking water. © 2013 © 2013 Taylor & Francis.
3-Acrylamidopropyl Cationic Hydrogel Modified Graphite Electrode and Its Superior Sensitivity To Hydrogen Peroxide
(Taylor & Francis inc, 2019) Caglar, Aykut; Kazici, Hilal Celik; Alpaslan, Duygu; Yilmaz, Yonca; Kivrak, Hilal; Aktas, Nahit
A highly sensitive hydrogen peroxide (H2O2) sensor is fabricated by the synthesized 3-Acrylamidopropyl-trimethylammoniumchloride (p(APTMACl)) hydrogel to covered of pen- graphite (PG) electrodes. (p(APTMACl))-PG electrode is characterized using scanning electron microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy, and thermogravimetric analysis (TGA). The electrochemical properties of these sensors are investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The CV behavior of (p(APTMACl))-PG electrode is investigated in 0.1M PBS (pH 7, 5mm diameter of mold). The developed sensor displays significantly enhanced electrocatalytic activity through the H2O2 detection. Linear response of the sensor to H2O2 were observed in the concentration range from 0 to 130 mu M (R-2 = 0.99) with a detection limit of 1.08x10(-6) M, quantification limit of 3.62x10(-6) M (S/N=3) and sensitivity of 2375 mu A/mMcm(2). In addition, interference studies reveal that (p(APTMACl))-PG electrode is not affected by ascorbic acid (AA), uric acid (UA), and dopamine which are common interfering species. The developed sensor is also successfully applied to detect H2O2 in real commercial samples. This study describes a novel strategy to sensing characteristics to hydrogen peroxide by p(APTMACl)-PG electrode.
A 3-Cm Single-Port Video-Assisted Thoracoscopic Lobectomy for Lung Cancer
(Lippincott Williams & Wilkins, 2015) Ocakcioglu, Ilhan; Sayir, Fuat; Dinc, Mustafa
Video-assisted thoracoscopic surgery is advantageous over traditional surgical practices, because of a faster postoperative recovery period, less pain, and a shorter hospital length of stay. There is no single standard technique in the video-assisted thoracoscopic surgery approach. Although these minimally invasive resections are habitually performed through 3-port or 4-port incision, we performed a left lower lobectomy in a 54-year-old male patient for lung cancer, through a 3-cm single-port incision.
The 3-D Strain Patterns in Turkey Using Geodetic Velocity Fields From the Rtk-Cors (Tr) Network
(Pergamon-elsevier Science Ltd, 2016) Kutoglu, Hakan Senol; Toker, Mustafa; Mekik, Cetin
This study presents our use of GPS data to obtain and quantify the full continuous strain tensor using a 3D velocity field in Turkey. In this study, GPS velocities improve the estimation of short-term strain tensor fields for determining the seismic hazard of Turkey. The tensorial analysis presents different aspects of deformation, such as the normal and shear strains, including their directions, the compressional and extensional strains. This analysis is appropriate for the characterizing the state of the current seismic deformation. GPS velocity data from continuous measurements (2009-2012) to estimate deformations were processed using the GAMIT/GLOBK software. Using high-rate GPS data from permanent 146 GNSS stations (RTK-CORS-TR network), the strain distribution was determined and interpolated using a biharmonic spline technique. We show the strain field patterns within axial and plane form at several critical locations, and discuss these results within the context of the seismic and tectonic deformation of Turkey. We conclude that the knowledge of the crustal strain patterns provides important information on the location of the main faults and strain accumulation for the hazard assessment. The results show an agreement between the seismic and tectonic strains confirming that there are active crustal deformations in Turkey. (C) 2015 Elsevier Ltd. All rights reserved.
The 3-D Strain Patterns in Turkey Using Geodetic Velocity Fields From the Rtk-Cors (Tr) Network (Vol 115, Pg 246, 2016)
(Pergamon-elsevier Science Ltd, 2016) Kutoglu, Hakan Senol; Toker, Mustafa; Mekik, Cetin
A 3-Day Boy With a Right Preauricular Swelling
(Springer, 2010) Akgun, Cihangir; Peker, Erdal; Akbayram, Sinan; Dogan, Murat; Tuncer, Oguz; Kirimi, Ercan
A 3-day-old boy was admitted for right preauricular swelling. Examination showed a toxic looking neonate with poor neonatal reflexes. There was erythema and swelling of 4 x 3 cm at the level of the right cheek. Laboratory investigation pointed to a bacterial infection. With parenteral antibiotics, the lesion resolved completely.
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.
3d-2d Microleakage Assessment of Preheated Bulk-Fill Composite Resin Applied With Different Parameters: a Micro-Ct Analysis
(Springer, 2023) Can, Dilber Bilgili; Ozarslan, Merve
This study evaluated microleakage from class II cavities filled with bulk-fill composite preheated to different temperatures, applied at different thicknesses, and with different polymerization modes. A total of 60 mesio-occlusal cavity were drilled into the extracted human third molars at 2 mm and 4 mm thickness. Preheated bulk-fill composite resin (Viscalor; VOCO, Germany) was applied to the cavities at 68 degrees C and 37 degrees C after the adhesive resin was applied, and cured using standard and high-power light-curing modes of a VALO light-curing unit. An incrementally applied microhybrid composite was used as the control. The teeth were subjected to 2000 cycles of heating to 55 degrees C and cooling to 5 degrees C with a 30-s hold time. Then, they were immersed in a 50% silver nitrate solution for 24 h and scanned with micro-computed tomography. Scanned data were processed using the CTAn software. Two (2D) and three (3D) dimensional analyses of leached silver nitrate were performed. The data's normality was assessed using the Shapiro-Wilk test before comparisons using a three-way analysis of variance. In both 2D and 3D analysis, bulk-fill composite resin preheated to 68 degrees C and applied at 2 mm thickness showed less microleakage. In the 3D analysis, restorations applied at 37 degrees C and 4 mm thickness in high-power mode showed significantly higher values (p < 0.001). Preheated bulk-fill composite resin can be applied at 68 degrees C and effectively cured at both 2 mm and 4 mm thickness.
4-Vinylpyridine Smart Nanoparticles With N-Isopropylacrylamide, 2-Hydroxyethyl Methacrylate, Acrylic Acid, and Methacrylic Acid for Potential Biomedical Applications
(Bentham Science Publ Ltd, 2011) Sahiner, Nurettin; Ozay, Ozgur; Aktas, Nahit
Stimuli-responsive (pH, temperature and magnetic field) 4-vinylpyridine (4-VP)-based nanoparticles in copolymeric formulation with core-shell morphology were synthesized using N-isopropylacrylamide (NIPAM), 2-hydroxyethyl methacrylate (HEMA), acrylic acid (AAc), and methacrylic acid (MAc) as shell-forming monomers. Keeping the 4-VP ratio constant and varying the comonomer amounts produced particles with variant shell thickness. Multi-responsive p(4-VP)-based nanoparticles were further modified by reacting with different functional groups containing bromoalkanes by quaternization. These p(4-VP)-based particles were also utilized to include composite materials by encapsulating separately prepared magnetic ferrites. To demonstrate the potential usage of the synthesized particles and their modified forms as drug delivery devices, naproxene sodium salt as an antibacterial drug was used for in vitro release studies in PBS.
6-Methylthiouracil and 6-Methyluracil Derivatives Synthesized by Reaction of Acetylketene With Thiourea and Urea Compounds in Presence of Yb(Tfa)3
(Taylor & Francis inc, 2023) Aslanoglu, Furgan; Yazici, Ahmet
Thiouracil and uracil derivatives are among the bioactive molecules used in the treatment of many diseases, such as 6-propylthiouracil and 5-fluorouracil. A new synthesis method of 6-methylthiouracil and 6-methyluracil was developed in this study. Various 6-methylthiouracil and 6-methyluracil derivatives were obtained by reacting 2,2,6-trimethyl-4H-1,3-dioxin-4-one with thiourea and urea compounds in the presence of Yb(TFA)(3) according to this new method. Optimization of this new method was performed. The structures of 6-methylthiouracil and 6-methyluracil derivatives were characterized.

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