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  • Öğe
    Correlation of metal ions with specific brain region volumes in neurodegenerative diseases
    (Tubitak Scientific & Technological Research Council Turkey, 2023) Melek, Ismet Murat; Kus, Berna; Kaptan, Zulal; Petekkaya, Emine
    Background/aim: There are reports stating that deteriorations in metal homeostasis in neurodegenerative diseases promote abnormal protein accumulation. In this study, the serum metal levels in Alzheimer's disease (AD) and Parkinson's disease (PD) and its relationship with the cortical regions of the brain were investigated. Materials and methods: The patients were divided into 3 groups consisting of the AD group, PD group, and healthy control group (n = 15 for each). The volumes of specific brain regions were measured over the participants' 3 -dimensional magnetic resonance images, and they were compared across the groups. Copper, zinc, iron, and ferritin levels in the serums were determined, and their correlations with the brain region volumes were examined. Results: The volumes of left hippocampus and right substantia nigra were lower in the AD and PD groups, while the volume of the left nucleus caudatus (CdN) and bilateral insula were lower in the AD group compared to the control group. Serum zinc levels were lower in the AD and PD groups, while the iron level was lower in the PD group in comparison to the control group. In addition, the serum ferritin level was higher in the AD group than in the control group. Serum zinc and copper levels in the AD group were positively corre-lated with the volumes of the right entorhinal cortex, thalamus, CdN, and insula. Serum zinc and copper levels in the PD group showed a negative correlation with the left nucleus accumbens (NAc), right putamen, and right insula volumes. While the serum ferritin level in the PD group displayed a positive correlation with the bilateral CdN, putamen, and NAc, as well as the right hippocampus and insula volumes, no area was detected that showed a correlation with the serum ferritin level in the AD group. Conclusion: A relationship was determined between the serum metal levels in the AD and PD groups and certain brain cortical regions that showed volumetric changes, which can be important for the early diagnosis of neurodegenerative diseases.
  • Öğe
    Removal of toxic Cr(VI) from aqueous medium with effective magnetic carbon-based nanocomposites
    (Tubitak Scientific & Technological Research Council Turkey, 2023) Cavusoglu, Ferda Civan; Ozcelik, Gulsum; Bayazit, Sahika Sena
    Cr(VI), which has toxic effects, is a heavy metal and it must be removed from the environment due to the various damages it causes. In this study, the removal of Cr(VI) pollutants from aqueous solutions with Fe3O4-based materials using a batch adsorption technique was investigated. Magnetically modified graphene nanoplatelet (GNP)-based nanocomposites were prepared and their structures were characterized by FTIR, XRD, SEM, BET, and TGA techniques. The effects of various physicochemical parameters such as adsorbent dose, contact time, initial Cr(VI) solution concentration, pH, and the presence of coexisting ions (NaCl) on the adsorption process were investigated. Accordingly, the optimum conditions for Cr(VI) removal were determined. Nonlinear Langmuir, Freundlich, and Temkin isotherm models and pseudo-first-order, pseudo-second-order, and Bangham kinetic models were used to investigate the adsorption mechanism. The experimental data relatively fit the second-order kinetic model and the Freundlich isotherm model. The maximum adsorption capacities for pure Fe3O4 (Fe:GNP 1:0), Fe:GNP (2:1), and Fe:GNP (1:1) nanocomposite materials at 298 K and pH of approximately 5 were obtained as 12.71 mg/g, 27.03 mg/g, and 62.27 mg/g, respectively. This result showed that Cr(VI) removal increased as the amount of GNP in the composite material increased. Generally, the results confirmed that magnetically modified GNP based adsorbents are functional and promising materials that can be used for the removal of pollutants such as Cr(VI) from aqueous media.
  • Öğe
    Decreased circulating microRNA-21 and microRNA-143 are associated to pulmonary hypertension
    (Tubitak Scientific & Technological Research Council Turkey, 2023) Duzgun, Zekeriya; Kayikcioglu, Meral; Aktan, Cagdas; Bara, Busra; Eroglu, Zuhal; Yagmur, Burcu; Cetintas, Vildan Bozok
    Background/aim: Pulmonary arterial hypertension (PAH) is characterized by maladaptation of pulmonary vasculature which is leading to right ventricular hypertrophy and heart failure. miRNAs play a crucial role in the regulation of many diseases such as viral infection, cancer, cardiovascular diseases, and pulmonary hypertension (PH). In this study, we aimed to investigate the expression pattern of eight human plasma miRNAs (hsa-miR-21-3p, hsa-miR-143-3p, hsa-miR-138-5p, hsa-miR-145-3p, hsa-miR-190a, hsa-miR-204-3p, hsa-miR-206, hsa-miR-210-3p) in mild-to-severe PH patients and healthy controls.Materials and methods: miRNAs were extracted from the peripheral plasma of the PH patients (n: 44) and healthy individuals (n: 30) by using the miRNA Isolation Kit. cDNA was synthesized using All in-One First strand cDNA Synthesis Kit. Expression of the human plasma hsa-miR-21-3p, hsa-miR-143-3p, hsa-miR-138-5p, hsa-miR-145-3p, hsa-miR-190a, hsa-miR-204-3p, hsa-miR-206, hsa-miR-210-3p, and miRNAs were analyzed by qRT-PCR.Results: According to our results, in PH patients hsa-miR-21-3p and hsa-miR-143-3p expression levels were decreased by 4.7 and 2.3 times, respectively. No significant changes were detected in hsa-miR-138-5p, hsa-miR-145-3p, hsa-miR-190a, hsa-miR-204-3p, hsa-miR-206, and hsa-miR-210-3p expression levels between PH and control groups. In addition, considering the severity of the disease, it was observed that the decrease in miR-138, miR-143, miR-145, miR-190, mir-204, mir-206 and miR-208 expressions was significant in patients with severe PH.Conclusion: In the early diagnosis of PAH, hsa-miR-21-3p and especially hsa-miR-143-3p in peripheral plasma can be considered as potential biomarkers.
  • Öğe
    The Role of Endoplasmic Reticulum Stress in Gastroesophageal Reflux Disease Symptoms and Treatment
    (Aves, 2023) Kasap, Elmas; Buran, Tahir; Avcu, Aysun Toraman; Hasdemir, Pinar Solmaz; Balcan, Erdal; Aktan, Cagdas; Korkmaz, Mehmet
    Background: Gastroesophageal reflux disease is a common condition worldwide. There is no curative treatment for gastroesophageal reflux disease. Endoplasmic reticulum stress leads to the activation of the unfolded protein response and has an important role in inflammation. The aim is to determine the role of endoplasmic reticulum stress in the follow-up of individuals with gastroesophageal reflux disease and the temporal changes of endoplasmic reticulum stress markers with treatment. Methods: Twenty-four subjects in total were recruited prospectively, of whom 15 had nonerosive reflux disease. Two biopsies from 2 cm above the esophagogastric junction, 2 biopsies from gastric antrum mucosa, and 2 biopsies from gastric corpus mucosa were taken. Simultaneously, 2 tubes of venous blood samples were drawn from each individual (1 tube for studying the genetic markers and 1 tube for analyzing the CYP2C19 polymorphism). Results: The mean age was 42.3 +/- 17.6 for women and 34.66 +/- 11.2 for men. Pantoprazole, esomeprazole, rabeprazole, and lansoprazole preparations were used for treatment. There was no significant difference between tissue and blood samples for panel genes ATF-6, XBP-1, DDIT-3, DNAJC-10, and EIF-2-AK before treatment. There was a significant decrease in the level of ATF-6, XBP-1, DNAJC-9, EIF2-AK, and NF-2L-2 genes in blood after treatment. In the comparison of proton pump inhibitors, significant decreases in the expression of the ATF-6, XBP-1, and DNAJC-9 mRNAs were detected in blood from individuals after treatment. Conclusion: Endoplasmic reticulum stress can be for evaluating the clinical improvement and the effectiveness of treatment in gastroesophageal reflux disease.
  • Öğe
    Inactive Platelet Rich Plasma in Culture Conditions Increases the Proliferation and Decreases the Apoptosis and Senescence of Human Adipose Derived Mesenchymal Stem Cells
    (Galenos Publ House, 2023) Salkin, Hasan
    BACKGROUND/AIMS: The aim of this study was to evaluate the effects of 10% platelet rich plasma (PRP) on the biological activity of human adipose-derived mesenchymal stem cells (hADSCs).MATERIALS AND METHODS: hADSCs were obtained from Erciyes University Gevher Nesibe Genom and Stem Cell Institute. The cells were transferred into plates at a density of 5,000 cells/cm2 in DMEM supplemented with 10% fetal bovine serum. Immunophenotyping was performed by means of primary antibodies selected against CD44, CD90, CD105, CD34, CD45 and CD73 antigens. The experimental groups were composed of 10% PRP treated cells (the study group) and untreated cells (the study group). 2,5-diphenyltetrazolium bromidetest was performed to demonstrate proliferation. Viability and apoptosis were evaluated in the experimental groups on days 1, 3 and 7. Senescent cells were determined by beta-galactosidase staining in the experimental groups on day 7.RESULTS: hADSCs were positive for the immunophenotype of mesenchymal stem cells. The viability and proliferation parameters were statistically significant and higher in the study group at days 1, 3 and 7. Apoptosis and senescence were lower in the 10% PRP group (p<0.05).CONCLUSION: 10% PRP increases proliferation and viability, and prevents the senescence and total apoptosis in hADSCs. In regenerative medical studies, 10% PRP can be used to increase the biological characteristics of hADSCs.
  • Öğe
    In-Vitro Bioactivity Investigation of Sol-Gel Derived Alumina-Bovine Hydroxyapatite (BHA) Composite Powders
    (Gazi Univ, 2020) Yelten, Azade; Karal-Yilmaz, Oksan; Akguner, Zeynep Puren; Bal-Ozturk, Ayca; Yilmaz, Suat
    Alumina (alpha-Al2O3) and hydroxyapatite (HA, Ca-10(PO4)(6)(OH)(2)) are well-known for being clinically successful bioceramic materials. In this work, in-vitro biological characterization of the sol-gel alumina-bovine hydroxyapatite composite powders was realized. Alumina powders were synthesized through the sol-gel process. First, boehmite (AlOOH) sol was prepared utilizing aluminium isopropoxide (Al(OC3H7)(3), AIP) as the starting precursor. Bovine hydroxyapatite (BHA) powders, which can be defined as naturally derived calcium phosphate powders were added as 10, 20, 30, and 50% wt. of AIP to each AlOOH sol. Homogeneous dispersion of the BHA powders in the AlOOH sol was managed due to employing Na-alginate as a kind of thickener. Gelation of the AlOOH-BHA mixtures was carried out at 110 degrees C for 3h. After drying, AlOOH-BHA mixtures were heat-treated at 1300 degrees C for 2h. Chemical, microstructural, thermal, and physical properties of the precursors/process products were characterized with X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Fluorescence Spectroscopy (XRF), Differential Thermal Analysis (DTA), and Scanning Electron Microscopy - Energy Dispersive Spectroscopy (SEM-EDS) analyses. Indirect MTT assay was done to evaluate the biocompatibility of the Al2O3-BHA based biocomposite extracts using the L929 cell line. It is found that all Al2O3-BHA composite extracts with varying doses of 25% and 50% had no negative effect on the cell viability. In addition, % cell viability decreased with the increasing of the extract concentration. It can be concluded that the prepared Al2O3-BHA composites can be a good candidate for biomedical applications.
  • Öğe
    High-performance CMOS CCI in a 0.35 ?m CMOS technology and a new all-pass filter application
    (Tubitak Scientific & Technological Research Council Turkey, 2013) Arslan, Emre; Metin, Bilgin; Cicekoglu, Mehmet Oguzhan; Morgul, Avni
    A differential pair-based, high-performance, first-generation current conveyor is proposed. The proposed circuit is laid out using the Mentor Graphics IC Station layout editor. The performance characteristics have been determined from HSpice postlayout simulations using the Austria Mikro Systeme 0.35 mu m, 3.3 V process parameters. During the simulations, +/- 1.65 V supply voltages and a 25 mu A biasing current are used. The power consumption is about 1.12 mW. The circuit also has very high voltage swings on ports X and Y, a very small impedance value on port X, high impedance values on ports Y and Z, and high-valued current and voltage transfer bandwidths. It is shown that the presented circuit can satisfy both the low-voltage/low-power and high-frequency performance current conveyor needs of the analog circuit applications. Furthermore, 2 new all-pass filter circuits as application examples are given and a procedure that can be used to search for the opportunities that would result from the use of the modified current conveyors is presented. Some special circuit topologies and new circuit function possibilities can be obtained by redesigning circuits with modified current conveyors, which is not possible with a standard current conveyor. The proposed approach is expected to allow deeper insight into circuit synthesis using modified current conveyors.
  • Öğe
    The Effect of Foot Massage on Pain and Anxiety Levels after Laparoscopic Cholecystectomy: A Randomized-Controlled Trial
    (Marmara Univ, Inst Health Sciences, 2021) Abdullayev, Aysegul; Ozbas, Ayfer
    Objective: This study was conducted to determine the effect of foot reflexology massage performed on patients after laparoscopic cholecystectomy on pain levels, analgesic use and anxiety levels. Methods: This prospective, experimental and randomized-controlled study was conducted with patients who underwent cholecystectomy. Ninety patients in total were divided into the experiment (n = 30), control (n = 30) and placebo (n = 30) groups. Foot reflexology massage was performed on the patients in the experiment group two times after surgery. Placebo massage was performed on the patients in the placebo group at the same times. Only routine treatment and care were given to the patients in the control group. The patients' pain and anxiety levels and their amounts of analgesic use within 24 hours were monitored. Results: The patients' state anxiety scores decreased significantly from the preoperative to the postoperative measurements, and the degree of decrease did not differ between the groups (p>0.05). The pain scores of the patients decreased after the first and second massage applications in all groups in comparison to their pre-massage scores, and the pain in the experiment group felt after the second massage was lower than that in the patients in the placebo group (p<0.01). It was found that analgesic administration for the patients within 24 hours after the operation did not differ in terms of quantity or time of administration (p>0.05). Conclusion: As a result, it may be stated that using reflexology with pharmacological methods to reduce postoperative pain will increase the effectiveness of pain treatment and the quality of nursing care.
  • Öğe
    Examining Sleep Quality and Job Satisfaction of Critical Care Nurses
    (Marmara Univ, Inst Health Sciences, 2020) Dogan, Hatice Dilek
    Objective: Ensuring patient safety in intensive care units, which constitute the key area of nursing profession, depends on protecting the safety of nurses. Intensive care units providing nonstop treatment in challenging conditions change the sleep quality, psychological and physiological rhythm of nurses. In this units nurses need to work very carefully always. Based on this thought, we aimed to examine the sleep quality and job satisfaction of intensive care nurses. Methods: 234 nurses from different intensive care units in five different hospitals participated in this descriptive cross-sectional study. Personal information form, Pittsburgh Sleep Quality Index (PSQI) and Minnesota Satisfaction Questionnaire (MSQ) were used in data analysis. Results: No differences were found among Pittsburgh Sleep Quality Index scores of nurses with respect to intensive care units, whereas Minnesota Satisfaction Questionnaire scores were found to be different (p<0.005). The average Pittsburgh Sleep Quality Index score was found to be 8.99 +/- 3.45. The highest Minnesota Satisfaction Questionnaire scores were found at level 3 general surgery, anesthesia intensive care units and neonatal intensive care units. A significant relationship was found between the job satisfaction of nurses and the duration of work in intensive care units (p<0.001). Conclusions: Although nurses were happy to work in intensive care units, their sleep quality was found to be 'poor' and their job satisfaction was found to be at 'medium level'. In order to improve sleep quality of intensive care nurses, working hours should be revised. It is recommended that managers make improvements that increase motivation and take into account the feedback of employees.
  • Öğe
    Berberine Attenuates Cerebral Vasospasm After Experimental Subarachnoid Hemorrhage Via Modulating AMPK/Rho Pathway
    (Dokuz Eylul Univ Inst Health Sciences, 2020) Kadirhan, Ozge Altintas; Kumas, Meltem; Karatas, Ersin; Mutlu, Hasan Serdar; Kocyigit, Abdurrahim; Asil, Talip
    Purpose: Our goal is to clarify the effectiveness of berberine (BBR) on cerebral vasospasm induced by subarachnoid hemorrhage. Methods: Thirty male Sprague-Dawley rats (350-400 g) were randomly allocated to five groups (sham group, SAH, BBR, SAH+BBR1 or SAH+BBR2. Experimental SAH model was induced by applying autologous blood into the cisterna magna at interval of 48 hours. To evaluate early and late effects of BBR, we allocated BBR treated groups as SAH+BBR1 and SAH+BBR2 (respectively, received BBR at a dose of 20 mg/kg 15 minutes and 6 hours after first SAH induction). Rats were sacrificed on 72-hour after the study onset. Cross-sections of basilar artery was investigated by histologically. Total antioxidant status (TAS) and total oxidant status (TOS) of brain tissue were studied by spectrophotometric assay. Oxidative stress index (OSI) was calculated. NAPPH Oxidase 4 (NOX4) enzyme levels were measured by ELISA method. Endothelial nitric oxide synthase (e-NOS), phosphorylated e-NOS (pe-NOS), AMP-activated protein kinase (AMPK), phosphorylated AMPK (pAMPK), Rho kinase and cingulin protein expressions were detected by Western blot analysis. Results: SAH+BBR1 and SAH+BBR2 groups significantly demonstrated lower OSI values, increased basilar artery cross-sectional luminal area in comparison with the SAH group. Increased Phosho-eNOS, eNOS, P-AMPK levels and Cingulin expression, decreased Nox4 and Rho-kinase levels were shown in BRB treated SAH groups relative to the SAH group. Conclusion: Berberine might be a neuroprotective agent to improve impaired cerebrovascular spasm.
  • Öğe
    Incoterms 2020
    (Istanbul Univ, 2020) Agaoglu, Cahit
    The Incoterms (R) are internationally accepted standards defined by the International Chamber of Commerce (ICC) and is a trademark of ICC, which define the responsibilities of sellers and buyers depending on how the goods are delivered in sales contracts. These international resources were created to eliminate the differences of interpretation and to accurately and fairly share the costs and risks of goods delivery. The latest version of these rules was enforced from January 01, 2020. With the appropriate consideration for the current commercial practices, the Incoterms (R) 2020 rules aim to be useful to the practitioners by updating the previous version of the Incoterms (R) 2010 rules. Thus, Incoterms (R) 2020 amended one of the existing terms and enriched the content of some terms. In our article, we have attempted to demonstrate the type of changes occurring for each item for different types of delivery in the Incoterms (R) 2020.
  • Öğe
    Estimation of the Global-Scale Ecological Footprint within the Framework of STIRPAT Models: The Quantile Regression Approach
    (Istanbul Univ, 2020) Topdag, Derya; Acar, Tugce; Celik, Ismail Erkan
    Despite the fundamental role of human-induced forces in global environment having changed, knowledge about the specific factors that cause these impacts is limited and uncertainties remain. In this respect, the ecological footprint emerges as a concept used to emphasize both the apparent unsustainability of current practices and the inequalities in resource consumption among countries. The ecological footprint provides a method for measuring how much land can support the consumption of natural resources and provides a precise measure of human impact on the world. In recent years, sustainable development and biological capacity debate has mainly revolved around factors affecting the ecological footprint and approaches to improving environmental quality. Therefore, it is important to determine which factors affect the global ecological footprint. For this aim, a cross-section analysis was carried out with the quantile regression approach applied within the framework of the STIRPAT model structure for 154 countries that were allocated according to their income levels in 2016, taking into account current data. According to the quantile regression findings, the coefficients of the welfare and financial development index are positive and statistically significant. It has been concluded that the population decreases the amount of ecological footprint per person, thus, increasing the total ecological footprint. In addition, it has been determined that the density of the service sector negatively affects the ecological footprint.
  • Öğe
    Financial Literacy, Behavioral Biases and Participation in Crypto Asset Markets
    (Eskisehir Osmangazi Univ, Fac Education, 2023) Ardogan, Ahmet Rutkay; Guel, Yavuz; Suyadal, Mehmetcan
    We have conducted a survey to determine the relationship between financial literacy and crypto market participation. Furthermore, we have included overconfidence and risk lover tendency, which are considered behavioral biases, in our models along with financial literacy. Logistic regression results revealed striking findings on financial literacy and crypto market participation. Our analysis shows that financial literacy has a positive significant impact on crypto market participation. Specifically, advanced financial literates are more likely to engage in crypto markets than basic financial literates. Confidence in financial decisions and risk - lover tendency also positively affect crypto investments, however these effects are insignificant. Apart from this, we determined a relationship between participation behavior and other control variables such as age, gender and investing in traditional assets. Lastly, we focus on Turkish crypto investors and find significant differences in respect of demographic factors in financial literacy and behavioral biases
  • Öğe
    Have Turkish Courts Started to Enforce Foreign Joint Custody Judgments?
    (Istanbul University Press, 2022) Ağaoğlu C.
    The approach of Turkish courts related to the enforcement of joint custody decisions is chang-ing in line with the international perspective. Important development and change arrive with the adoption of the “Protocol No. 7 amended with Protocol No. 11, Annex to the Convention on the Protection of Human Rights and Fundamental Freedoms” (Protocol No. 7). Referring to this, Turkish Courts have both started to rule in favor of joint custody and started to en-force foreign joint custody judgments. The decision of the Supreme Court 2nd Legal Depart-ment, dated February 20, 2017, numbered E. 2016/15771, K. 2017/1737 has been the turning point on this. We expect that this encouraging attitude of the Supreme Court will positively affect the enforcement of foreign joint custody decisions, especially in cases where joint cus-tody is in the best interest of the child and the fact that the issue of joint custody after divorce is not regulated in Turkish Law will no longer face public policy interference. However, in order to achieve this, we are of the opinion that provisions that bring a detailed arrangement related to joint custody should be included in the “Turkish Civil Code” (TCC). © 2022 Istanbul University Press. All Rights Reserved.
  • Öğe
    Evaluating the Effect of Different Laser Types on Dentin Fracture Resistance
    (Cumhuriyet University Faculty of Dentistry, 2021) Ürkmez H.F.; Güneç H.G.; Haznedaroğlu F.
    Objectives: The aim of this in vitro study was to use fracture testing methods to evaluate the impact of the use of different laser types–particularly diode, Nd:YAG and Er:YAG lasers–on dentin fracture resistance. Materials and Methods: Ninety human maxillary incisors were used. The teeth were divided into three experimental groups and three control groups, each containing 15 samples. The laser treatments were a diode laser for experimental group 1, a Nd:YAG laser for experimental group 2, and an Er:YAG laser for experimental group 3. The teeth were then dried and obturated using the AH-Plus sealer and RevoS AS40 gutta percha (GP). Control group 1 was obturated as in the experimental groups but without laser application; control group 2 was instrumented but not obturated; and negative control group 3 had no procedure performed at all. All samples were fixed in acrylic blocks and were subjected to fracture tests using an Autograph Universal Testing Machine. The results were analysed using IBM SPSS Statistics 22 software, one-way ANOVA test and Tukey’s HSD test (to identify groups that cause a difference), with p<0.05 indicating statistical significance. Results: The applied force was significantly lower for control group 2 than for the Er:YAG laser or negative control groups (p<0.05). The remaining groups showed no statistically significant differences (p>0.05) Conclusions: The findings presented here support the conclusions that the use of Nd:YAG, Er:YAG and diode lasers in endodontic treatments has no negative impact on dentin fracture resistance and that these lasers can be used safely. © 2021. All Rights Reserved.
  • Öğe
    The effect of cyclic relative humidity exposure, sanding and grooving on the dimensional stability of solid wood parquet
    (Istanbul Teknik Universitesi, Faculty of Architecture, 2018) Koca G.; Arioğlu N.; As N.
    In this study, the effect of cyclic relative humidity changes, sanding and grooving on the dimensional stability of solid wood parquet were evaluated. The experiments were carried out on oak (Quercus petraea) and sapele (Entandrophrag-ma cylindiricum) wood species. Firstly some physical tests (density, shrinkage, and swelling) were carried out on 20×20×30 mm specimens obtained from these two species. After the physical tests the parquet size specimen groups were obtained both in radial and tangential section directions and in two sizes; narrow (250×50×15 mm) and wide (250×90×15 mm). One group of parquet size specimens was sanded and the other group was grooved. There was also a group of specimen for control. After being conditioned to equilibrium moisture content at 65% relative humidity, specimens were placed in a climate chamber and exposed to cyclic relative humidity changes. The dimensions of the specimens were measured between different environmental conditions and the dimensional change was evaluated by taking into consideration the mentioned physical properties. The results show that cyclic relative humidity changes mainly resulted with an increase in the dimensional stability of sanded and cyclic conditioned specimens. There was not a significant change in the dimensional stability of grooved specimens. © 2018, Istanbul Teknik Universitesi, Faculty of Architecture. All rights reserved.
  • Öğe
    Third generation current conveyor based current-mode first order all-pass filter and quadrature oscillator
    (2008) Ün M.; Kaçar F.
    A novel current-mode first order all-pass filter configuration is proposed. The proposed circuit uses a third generation current conveyor (CCIII), resistors and a capacitor. Since the output of the filter exhibits low output impedance the synthesized filter can be cascaded without additional buffers. To demonstrate the performance of the proposed filter a new current-mode quadrature oscillator is introduced as an application example. For non-ideal CCIII all-pass filter condition is derived and oscillation condition and frequency of the quadrature oscillator circuit are also presented. The theoretical results are verified with PSPICE simulations using CMOS realization of the CCIII.
  • Öğe
    On the inclusion properties for ?-spirallike functions involving both Mittag-Leffler and Wright function
    (TUBITAK, 2022) Altinkaya Ş.
    By making use of the both Mittag-Leffler and Wright function, we establish a new subfamily of the class S? of ?-spirallike functions. The main object of the paper is to provide sufficient conditions for a function to be in this newly established class and to discuss subordination outcomes. © This work is licensed under a Creative Commons Attribution 4.0 International License.
  • Öğe
    Bir Kore Şehidimiz ve Ardından Yazılanlara
    (2007) Ülgen, Erol
    Türkiye, 1950 yılında Birleşmiş Milletler’in çağrısına uyarak, Güney Kore’nin yanında çoğu gönüllülerden oluşan yeni bir tugayla sava-şa katılır. Bu vesileyle NATO’ya girer. Bu acımasız savaşın gönüllü kah-raman subayları arasında Kırşehirli Kd. Yzb. Esat Nadir Öztüzün de var-dır. Çocukluk hayatı çok çetin geçen Öztüzün’ün meslek hayatı başarılar-la doludur. Henüz 32 yaşındayken 22 Kasım 1950’de Kunuri’de şehit o-lur. Bu çalışmada yakın tarih hatırlatılmış, şehit Öztüzün, kaynaklara da-yalı olarak çeşitli yönleriyle tanıtılmış ve anlatılmıştır.
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    Egzersiz bağımlılığı ölçeği-21'in Türkçe geçerlilik ve güvenilirlik çalışması
    (2007) İkizler, H. Can; Yeltepe, Hülya
    Amaç: Egzersiz Bağımlılığı Ölçeği-21, (EBÖ-21) Hausenblas ve Downs (2002) tarafından egzersiz bağımlılığının tespiti için geliştirilmiş, 21 sorudan oluşan bir kendini değerlendirme ölçeğidir. Bu çalışmada, egzersiz bağımlılığının tanımlanması ve uzun süredir, yüksek şiddette ve sıklıkta egzersiz yapan bireylerde egzersiz bağımlılığının saptanması için Egzersiz Bağımlılığı Ölçeği-21'in (EBÖ-21) Türkçe geçerlilik ve güvenilirlik çalışmasının yapılması amaçlanmıştır. Yöntem: İstanbul ilindeki Pamukspor, Darüşşafaka, Enka ve İTÜ" Spor Merkezlerinde iki yıl ve üzeri egzersiz yapanlar ile iki yıldır hiç egzersiz yapmayanlar çalışma kapsamına alınmıştır. Çalışma örneklemini, hiç egzersiz yapmayan (n= 38), haftada üç-dört gün egzersiz yapan (n=41) ve haftada beş gün ve üzeri egzersiz yapan (n=45), 124 katılımcı oluşturmuştur. Çalışma iki aşamadan oluşmuştur. İlk aşamada! Ölçeğin (EBÖ-21) test-tekrar test geçerlilik ve güvenilirliğinin sağlanması için EBÖ-21, katılımcılara iki haftalık ara ile uygulanmıştır. İkinci aşamada, örneklem grubu içerisindeki egzersiz bağımlısı bir grubun varlığına bakılmıştır. Ayrıca egzersiz bağımlılığı ile egzersize katılım yılı ve haftadaki egzersiz yapma sıklığı arasındaki ilişki incelenmiştir. Bulgular: Güvenilirlik analizi sonucunda ilk test için (Cronbach) a=0.96 ve ikinci test için de (Cronbach) a=0.97 bulunmuştur. Ayrıca test ve tekrar test uygulamalar arasında yapılan Pearson Korelasyon analizlerinde bütün maddeler için PO.001 düzeyinde anlamlılık bulunmuştur. Örneklem grubunda, n=14 kişinin egzersiz bağımlısı olduğu tespit edilmiştir. Egzersiz bağımlılığının haftada beş gün ve üzeri sıklıkta egzersiz yapanlar (n=13) ile beş yıl ve daha uzun süredir egzersiz yapanlar (n=10) arasında yaygın olduğu tespit edilmiştir. Bu veriler egzersiz bağımlılığı ile egzersize katılım yılı ve haftadaki egzersiz yapma sıklığı arasında pozitif bir ilişki olduğunu göstermektedir. Sonuç: Bu çalışmanın bulguları "Egzersiz Bağımlılığı Ölçeği-21 (EBÖ-21 )"in Türkçe çevirisinin uzun süredir, yüksek şiddette ve sıklıkta egzersiz yapan bireylerde egzersiz bağımlılığını tespit etmek için geçerli ve güvenilir olarak kullanılabileceğini düşündürmektedir.