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Koleksiyondaki öğeler
- MakaleYalnız künye2016Scopus SJRQ3PHYTOCHEMICAL PROFILES OF WILD GROWN BLACKBERRY AND MULBERRY IN TURKEY
Akin, Meleksen; Eyduran, Sadiye Peral; Ercisli, Sezai; Yilmaz, Ilker; Cakir, Ozlem
Blackberry and mulberry are main berry crops grown in Black Sea region mostly in humid shade forest areas and its important for local people's diet and also important for the maintenance of their health and prevention of disease. Present study aimed to determine the content of vitamin C, organic acids (citric acid, tartaric acid, oxalic acid, malic acid, succinic acid, fumaric acid), sugars (glucose and fructose) and phenolic compounds (catechin, rutin, quercetin, chlorogenic acid, ferulic acid, o-coumaric acid, p-coumaric acid, caffeic acid, syringic acid, vanillic acid, and gallic acid), as well as antioxidant capacity (Trolox Equivalent Antioxidant Capacity, TEAC assay) in the wild grown blackberry and mulberry fruit. Among phenolic acids, chlorogenic acid was the predominant for all wild grown blackberries, white and black mulberries. The presence of oxalic acid was only detected in the wild blackberry genotype. As a result, the phytochemical recognition of the wild grown blackberry, black and white mulberries might contribute to forthcoming investigations for developing the efficiency of food industry.
AtıfWoS8
İncele - MakaleAçık Erişim2026Scopus SJRQ1Role of occupational self-efficacy and professional identity as mediators in the relationship between person-job fit and career sustainability among teachers
Demir, Mustafa; Yayla, Ibrahim Erdogan; Dombak, Kubra; Baloglu, Mustafa
Introduction Career sustainability has become increasingly important for teachers to maintain long-term professional engagement and effectiveness. This study examined the serial mediating roles of occupational self-efficacy and professional identity in the relationship between person-job fit and career sustainability among teachers.Methods The study employed a correlational survey design. A total of 390 teachers working in Turkiye participated in the study. Data were collected using the Career Sustainability Scale, the Person-Job Fit Scale, the Occupational Self-efficacy Scale, and the Perceived Professional Identity Scale. We tested the research hypotheses using a serial mediation analysis with Hayes' PROCESS Macro Model 6.Results The findings show positive and significant relationships among person-job fit, occupational self-efficacy, professional identity, and career sustainability. Although the direct effect of person-job fit on career sustainability is not statistically significant, the indirect effects via occupational self-efficacy and professional identity are significant. The serial mediation analysis further shows that person-job fit is related to teachers' occupational self-efficacy, which may, in turn, be related to their professional identity and, consequently, to career sustainability.Conclusion The findings indicate a significant indirect relationship between person-job fit and teachers' career sustainability, mediated by occupational self-efficacy and professional identity. These findings highlight the importance of holistically considering person-job fit, occupational self-efficacy, and professional identity for teacher career sustainability.
- MakaleYalnız künye2018Scopus SJRQ2Plant Origins of Propolis from Hakkari, Turkey
Ecem Bayram, Nesrin; Sorkun, Kadriye; Cevahir Oz, Gul
In this study, palynological analysis of 64 propolis samples from Hakkari province in Eastern Anatolia Region of Turkey was carried out. By microscopic analysis method, pollen diagnosis was made in propolis samples, and plants which may be propolis sources, were estimated. As a result, 71 plant taxa belonging to 34 families were identified at different rates in propolis samples. The pollens of the plants belonging to the family Apiaceae (2.7%-35%), Asteraceae (3.4%-35.4%) and, Fabaceae (12%-66%) were considerably found in the propolis of the Hakkari province. This study is the first report introducing the plant profile of Hakkari propolis in detail.
AtıfWoS1İncele - MakaleYalnız künye2015Scopus SJRQ3Effect of Chemical Composition and Grain Size on RT Superplasticity of Zn-Al alloys processed by ECAP
Demirtas, M.; Purcek, G.; Yanar, H.; Zhang, Z. J.; Zhang, Z. F.
Dilute Zn-0.3Al, eutectic Zn-5Al and eutectoid Zn-22Al alloys were processed by multi-pass equal channel angular pressing (ECAP) in order to achieve fine grained (FG) or ultrafine-grained (UFG) microstructure and room temperature (RT) superplasticity. ECAP refined the microstructure of Zn-0.3Al and resulted in a FG Zn-rich.-matrix with an average grain size of 2 mu m and homogeneously distributed nano-sized Al-rich a-particles with the grain sizes in the range of 50-200 nm. A bi-modal microstructure was achieved in Zn-5Al alloy with UFG Al-rich a-and FG Zn-rich.-phases having mean grain sizes of 110 nm and 540 nm, respectively. ECAP brought about an agglomerate-free UFG microstructure in Zn-22Al alloy with an average grain size of 200 nm which is the lowest one obtained so far for this alloy after ECAP processing. The maximum RT superplastic elongations of 1000%, 520% and 400% were achieved for Zn-0.3Al, Zn-5Al and Zn-22Al alloys, respectively. Considering the RT superplasticity in Zn-Al alloys, it was found that lower Al content results in higher superplastic elongations even if the alloy has relatively larger grain size. Grain boundary sliding (GBS) was found to be the main deformation mechanism in region-II as the optimum superplastic region during RT deformation for all three Zn-Al alloys with the strain rate sensitivity factor ranging between 0.25-0.31.
AtıfWoS19İncele - MakaleYalnız künye2021BIOCHEMICAL AND BIOACTIVE CONTENT IN FRUITS OF WALNUT (JUGLANS REGIA L.) GENOTYPES FROM TURKEY
Erdogan, Ummugulsum; Argin, Sanem; Turan, Metin; Cakmakci, Ramazan; Olgun, Murat
Walnuts (Juglans regia L.) are a good source of dietary minerals and contain significant amounts of potassium, phosphorus, magnesium and iron. In Turkey, walnut orchards are found in the coruh Valley and are generally composed of local varieties. Since chemical and physical properties of walnuts are very important in determining their quality, in this study, nut and kernel characteristics, fatty acid composition and phenolic composition were determined for 26 walnut genotypes collected from the valley. Total fat content was found to be between 53.75% and 71.43%, while the crude protein amount ranged from 10.21% to 20.71%. Total carbohydrates were calculated between 14.31-27.52% and ash content was found to be between 1.64% and 3.32%. The oleic acid content and linoleic acid content ranged from 18.34 to 25.58% and 37.09% to 87.51%, respectively. The linolenic acid content was determined between 5.52% and 11.03%. Our study showed that, differences in phenolic component, crude protein and fatty acid content of walnuts were caused by different growing conditions. Genotypes have a rich and stable structure in terms of fruit quality parameters, minerals, organic acids, phenolic composition, antioxidant and fatty acids amounts and amino acids. In other words, these characteristics did not show much variation in genotypes grown in the Valley. However, there was a great variation in hormone levels among genotypes. In terms of the parameters examined, GN2, GNI, ((NIS, GN24, GN25 and GN26 genotypes were determined as rich and stable genotypes.
AtıfWoS8İncele - MakaleYalnız künye2017The effect of extreme sports on oxidative stress
Aggon, Eser; Agirbas, Ozturk; Ucan, Izzet; Hackney, Anthony C.
Background & Study Aim: Despite the high risk of extreme sports, participation rates have increased in the last years. Rafting and paragliding are two of the most popular extreme sports. The aim of this study was the effect of rafting and paragliding exercises in males on oxidative stress situation and antioxidant status. Material & Methods: Seventeen male rafters and ten male paragliders voluntarily participated in the study. The inclusion criteria were: non-smoker, no known history of cardiovascular disease, body mass index (BMI) < 30 kg/m2, and no intake of medications or antioxidant supplements. Blood samples were taken at rafting and paragliding practices' a day before and after the sporting activities. The data were statistically analysed with Wilcoxon and Mann-Whitney U tests. Results: Rafting activity increased the values of the total antioxidant situation (TAS), paragliding exercises decreased the level of TAS while paragliding increased the level of total oxidative stress (TOS). Differences existed between the group only before activities in TAS values. Conclusions: The specific property of the rafting workout is to stimulate of participants to cope with oxidative stress by activating the antioxidant status. In turn paragliding exercises increase oxidative stress due to the danger element in the sport and perhaps requiring the participants stay at a high altitude, in some situations, during its practice.
AtıfWoS1İncele - MakaleAçık Erişim2018Investigation of alloying effects on XRF parameters of 3d transition metals in Permendur49, Kovar and Ti50Co50 alloys
Alim, Bunyamin; Ugurlu, Mine; Han, Ibrahim; Demir, Lutfu
The alloying effects on X-ray fluorescence (XRF) parameters such as K shell fluorescence cross-sections (sigma(K alpha), sigma(K beta) and sigma(K)), K shell average fluorescence yields (omega(K)) and K to L shell vacancy transfer probabilities (eta(KL)) of V, Ti, Fe, Co and Ni 3d transition metals in Permendur49 (Fe49Co49V2), Kovar (Fe54Ni29Co17) and Ti50Co50 alloys have been carried out by X-ray fluorescence studies. K X-ray intensity ratios of these 3d transition metals in both pure form and present alloys have been measured following excitation by 22.69 keV X-rays from a 10 mCi Cd-109 radioactive point source. The characteristic K-X-ray spectra from samples were detected by a high-resolution Si(Li) solid-state detector. The investigated fluorescence parameters of present 3d transition elements in alloys indicate significant differences with respect to the pure metals. Consequently, the observed change of the investigated fluorescence parameters can be attributed to the delocalization and charge transfer phenomena between the 3d elements in alloys. (c) 2017 The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V.
AtıfWoS7OpenAlex8İncele - MakaleAçık Erişim2026The Frequency-Dependent Electrical Properties and Fabrication of Diode
Sevgili, Omer; Orak, Ikram; Özel, Sultan Suleyman; Özel, Faruk
The fabrication of Al/NiO/p-Si Schottky diode (SD) was formed using a thermal evaporation system. The structural analyze of NiO using an interfacial layer was conducted using a Scanning Electron Microscope (SEM) and the SEM cross-section revealed a thickness of 0.0345 mu m for NiO interfacial layer. The capacitance-voltage (C-V) and conductance-voltage (G/omega-V) measurements of the fabricated SD were performed in the 50 kHz to 5 MHz frequency range and in the-3 V to +3 V range. The Nicollian-Brews method was employed to calculate the series resistance (Rs), while the high-low frequency capacitance method (CHF-CLF) was used to calculate the surface states (Nss). The value of the Nss was determined to be in the order of 1012 eV-1cm-2. These findings suggest that NiO is a promising alternative to conventional insulating layers in electronic devices.
- MakaleAçık Erişim2018Alloying effect on K shell X-ray fluorescence cross-sections and yields in Ti-Ni based shape memory alloys
Alim, Bunyamin; Han, Ibrahim; Demir, Lutfu
K shell X-ray fluorescence cross-sections (sigma(K alpha), sigma(K beta) and sigma(K)), and K shell fluorescence yields (omega(K)) of Ti, Ni both in pure metals and in different alloy compositions (TixNi1-x; x = 0.3, 0.4, 0.5, 0.6, 0.7) were measured by using energy dispersive X-ray fluorescence (EDXRF) technique. The samples were excited by 22.69 keV X-rays from a 10 mCi Cd-109 radioactive point source and K X rays emitted by samples were counted by a high resolution Si(Li) solid-state detector coupled to a 4 K multichannel analyzer (MCA). The alloying effects on the X-ray fluorescence (XRF) parameters of Ti-Ni shape memory alloys (SMAs) were investigated. It is clearly observed that alloying effect causes to change in K shell XRF parameter values in Ti-Ni based SMAs for different compositions of x. Also, the present investigation makes it possible to perform reliable interpretation of experimental sigma(K alpha), sigma(K beta) and omega(K) values for Ti and Ni in SMAs and can also provide quantitative information about the changes of K shell X-ray fluorescence cross sections and fluorescence yields of these metals with alloy composition. (c) 2017 The Egyptian Society of Radiation Sciences and Applications. Production and hosting by Elsevier B.V.
AtıfWoS3OpenAlex8İncele - MakaleAçık Erişim2021Scopus SJRQ1Measurement of Propagation Characteristics of Nonreciprocal Networks/Lines Using a Line-Line Method
Hasar, Ugur C.; Kaya, Yunus; Ertugrul, Mehmet
In this article have proposed a new calibration-free line-line method for propagation constant (gamma) determination of homogeneous nonreciprocal networks or lines with symmetric reflection property. To achieve our goal, wave-cascading matrices for impedance, amplitude, and phase changes for a line step from a homogeneous reciprocal network or line to a homogeneous nonreciprocal network or line (and vice versa). Two different approaches based on the proposed line-line method are proposed for unique extraction of gamma in forward and backward directions. Measurements of gamma for two reciprocal lines (waveguide straights at X-band and Ku-band with different lengths) and a nonreciprocal line (microwave phase shifter) were first carried out and then compared with measured gamma of these lines by different methods to validate our method and monitor its accuracy.
AtıfWoS4OpenAlex5İncele - BildiriAçık Erişim2017Scopus SJRQ1Nanoemulsion-based delivery systems to improve functionality of oregano essential oil: Molecular characterization and in vitro antifungal activity
Ermis, Ertan; Cicek, Perihan Kubra; Meral, Raciye; Yilmaz, Azime; Dertli, Enes; Yilmaz, Mustafa Tahsin
AtıfWoS1OpenAlex1İncele - MakaleYalnız künye2022Scopus SJRQ1Nondestructive Experimental Measurement, Model Updating, and Fatigue Life Assessment of carsamba Suspension Bridge
Günaydin, Murat; Sunca, Fezayil; Altunisik, Ahmet Can; Ergün, Mustafa; Okur, Fatih Yesevi
This paper includes the structural condition assessment of a 164-m suspension bridge in accordance with numerical and experimental methods. A finite-element model was developed using SAP2000 software so that the assessment of the bridge could be calculated numerically. The operational modal analysis method was also used to obtain experimental dynamic characteristics. In this context: (i) numerical dynamic characteristics of the bridge were obtained and compared with the experimental dynamic characteristics, (ii) a model updating procedure was carried out to minimize the differences between the numerical and experimental natural frequencies, (iii) static and dynamic analyses of the bridge were carried out by using the initial and updated finite-element models, (iv) fatigue life assessment of the bridge was investigated, and (v) the utility of the bridge for pedestrians and vehicles was checked according to various regulations. The results showed that updating the finite-element model had a significant role to play in the static and dynamic behavior of the bridge. The results also demonstrated that the bridge was designed to be extremely safe against static, dynamic, and fatigue loads. Finally, it was concluded that the bridge investigated behaves as a girder bridge rather than a suspension bridge.
AtıfWoS17OpenAlex18İncele - BildiriAçık Erişim2022Implementation of a SoC by Using lowRISC Architecture on an FPGA for Image Filtering Applications
Akçay, Latif; Sürer, Bartu; Yalçin, Berna Ors
In this study, it is aimed to implement the lowRISC system-on-chip, which is based on the Rocket processor created with the RISC-V instruction set architecture developed by Berkeley University, on FPGA and to run image processing algorithms on this system. While making this implementation, the main target is a system that is very simple, consumes low power, and can be quickly redirected to other purposes. Therefore, it is based on the effective evaluation of the existing system without using any extra customized accelerators. Thus, a free, open source, and powerful enough platform for many embedded system applications is proposed to the designers. For this purpose, a lane detection application designed with standard C libraries such as Gaussian blur filter, Sobel operation filter and other elements, which are widely used in image processing applications, is run with embedded Linux operating system and the results are shared.
AtıfOpenAlex1İncele - MakaleAçık Erişim2024GENERALIZED n-POLYNOMIAL P- FUNCTIONS WITH SOME RELATED INEQUALITIES AND THEIR APPLICATIONS
Ozcan, Serap; Kadakal, Mahir; Iscan, Imdat; Kadakal, Huriye
In this paper, we introduce the notion of generalized n-polynomial Pfunction. We explore some algebraic properties of this function class. Additionally, we establish a new trapezium type inequality for this generalized class of functions and derive several refinements of the trapezium type inequality for functions whose first derivative in absolute value at a certain power is generalized n-polynomial P-function. Finally, we conclude our paper by exploring some applications of the results we have obtained in the context of special means. Our novel findings generalize previously known results in the literature.
AtıfWoS1OpenAlex1İncele - MakaleAçık Erişim2019Scopus SJRQ2Determination of Thermal Conductivity Properties in Some Wood Species Obtained from Turkey
Çavus, Vedat; Sahin, Siri; Esteves, Bruno; Ayata, Umit
With the increased awareness of thermal insulation of buildings, the knowledge of thermal conductivity of non-structural materials applied for roughing, cladding or flooring has become more important. The objective of this study was to investigate the thermal conductivity of 31 different wood species originated from the region of Izmir in Turkey. Thermal conductivity of air dried boards was determined in accordance to ASTM 5334 standard which measures this property on the interior of wood rather than on the surface. Thermal conductivity varied from 0.090 to 0.197 W/ mK. The highest thermal conductivity was obtained for oak and the lowest for Canadian poplar. A linear relation was obtained between wood density and thermal conductivity.
AtıfWoS42OpenAlex58İncele - BildiriAçık Erişim2014Investigation of Pre-service Science Teachers' Self-efficacy Beliefs of Science Teaching
Kahraman, Sakip; Yilmaz, Zeynel Abidin; Bayrak, Ramis; Gunes, Kubra
The scope of the study is to investigate the pre-service science teachers' self-efficacy beliefs of science teaching with respect to gender and grade level. Using the survey approach, the data of the study were gathered from 114 pre-service science teachers enrolled in the Faculty of Education at two universities in Turkey. The data was collected using a likert type scale, science teaching self-efficacy belief scale with 23 items, originally developed by Enochs-Riggs (1990). Variance analyses (two-way ANOVA) was performed on the collected data to reveal whether there are significant differences in science teacher candidates' self-efficacy beliefs of science teaching according to grade level and gender. The results of analysis showed that there was no statistically significant difference in pre-service science teachers' self-efficacy beliefs of science teaching with respect to both gender and grade level. (C) 2014 The Authors. Published by Elsevier Ltd.
AtıfWoS3OpenAlex16İncele - MakaleAçık Erişim2023Effect of Reboxetine Treatment on BDNF, Synaptophysin, and PSD-95 Levels in the Spinal Dorsal Horn of Rats with Diabetic Neuropathy
Yücel, Nazli Turan; Üçel, Umut Irfan; Özkay, Umide Demir; Ulupinar, Emel; Can, Ozgur Devrim
Objective: It is known that neuropathic pain is accompanied by alterations in the levels of neurotrophic factors and synaptic proteins in the microenvironment of the spinal dorsal horn. Such changes contribute to hyperalgesia and allodynia processes; thus, analgesic drugs can exert their pharmacological effects by affecting the expressions, levels, or functions of these endogenous substances. In this study, based on the knowledge that reboxetine (a selective noradrenaline reuptake inhibitor) has the potential for antihyperalgesic efficacy in diabetic neuropathy, we aimed to examine the probable effects of this drug on diabetes-induced changes in brain-derived neurotrophic factor (BDNF), synaptophysin (the pre-synaptic marker of synaptic integration), and postsynaptic density-95 (PSD-95) (the postsynaptic marker of synaptic integration) levels in the superficial laminae of the dorsal horn.Methods: Experimental diabetes was induced by a single-dose injection of streptozotocin (STZ) (50 mg/kg) in rats. After four week-long induction period of painful diabetic neuropathy, rats were treated orally with 8 mg/kg reboxetine for two weeks. Hyperalgesia responses were evaluated by using the Randall-Selitto and Hargreave's tests. Following the pain tests, immunohistochemical studies were performed.Results: Two weeks of reboxetine administration increased the reduced paw withdrawal thresholds and shortened the paw withdrawal latencies of diabetic rats in neuropathic pain tests, indicating the antihyperalgesic efficacy of this drug. Moreover, augmented BDNF and synaptophysin levels in diabetic rats reversed by reboxetine treatment. However, there was no alteration in the densities of PSD-95, in both STZ-diabetic and reboxetine-treated STZ-diabetic rats.Conclusion: The obtained results suggested that inhibition of central sensitization and modulation of spinal plasticity seem to be pharmacological mechanisms underlying reboxetine's antihyperalgesic effects on diabetic rats. However, further studies are still needed to clarify the exact mechanism of action.
AtıfWoS1OpenAlex1
İncele - MakaleYalnız künye2016ANALYSIS OF A LONG STRIP CONTAINING AN INTERNAL OR EDGE CRACK USING FEM
Yaylaci, Murat; Birinci, Ahmet; Adiyaman, Gokhan; Öner, Erdal
This paper presents the elastostatic plane problem of a long strip containing an internal or edge crack perpendicular to its boundaries. The plane problem consists of an infinitely long strip of thickness h. The infinitely long strip is loaded by uniformly distributed load and rests on two simple supports. It is assumed that the effect of gravity is neglected. The finite element model of the problem is constituted using ANSYS software and the two dimensional analysis of the problem is carried out. Normalized stress-intensity factors for the cases with internal and edge crack, and normal stress (sigma(x)) for uncracked layer case are obtained for various dimensionless quantities. Finally, the results obtained from the finite element analysis are verified by comparing with analytical ones and it is seen that the results from finite element analysis indicate a good agreement with the analytical solution.
AtıfWoS4İncele - MakaleAçık Erişim2025INVESTIGATION OF SURGICAL NURSES' ANXIETY AND GENERAL ATTITUDES TOWARDS ARTIFICAL INTELLIGENCE
Günes, Huseyin; Okutan, Serafettin; Dolanbay, Nihal; Bostanci, Meric Emre
Purpose: This study was conducted to determine the general anxiety and attitudes of surgical nurses toward artificial intelligence. Method: This study was designed as descriptive and correlational with the participation of 335 surgical nurses working in two different hospitals in the Eastern and Central Anatolia regions of Turkey between 06.02.2025-01.06.2025 dates. Results: The scores obtained from the positive and negative attitude sub-dimensions of the General Attitudes towards Artificial Intelligence Scale are moderate (40.24 +/- 8.94, 23.65 +/- 6.61). The total score of the Artificial Intelligence Anxiety Scale is moderate (46.09 +/- 13.65). A low level of negative correlation was found between the positive attitude scores of the General Attitudes towards Artificial Intelligence Scale and the total scores of the Artificial Intelligence Anxiety Scale (r=-0.239, p<0.001). A high level of positive correlation was found between the negative attitude scores of the General Attitudes towards Artificial Intelligence Scale and the total scores of the Artificial Intelligence Anxiety Scale (r=0.710, p<0.001). In the multiple linear regression model established, it was seen that 53% of the anxiety toward artificial intelligence was explained by the general attitudes towards artificial intelligence variable, which is the independent variable in the model (R2=0.530). Conclusion: As the positive attitudes of surgical nurses toward artificial intelligence increase, their anxiety levels toward artificial intelligence decrease. It is necessary to provide continuous education and support to surgical nurses about artificial intelligence applications.
AtıfTR Dizin1İncele - MakaleYalnız künye2019Scopus SJRQ4DETERMINATION OF ANTIOXIDANT, ANTIMICROBIAL ACTIVITIES, PHENOLIC COMPOUNDS OF WILD ROSA L. SPECIES BAYBURT, TURKEY
Gidik, Betul; Akar, Zeynep; Can, Zehra; Sefali, Abdurrahman; Erturk, Omer
Five different rosehip (Rosa L.) species including, Rosa canina, Rosa iberica Stev, Rosa villosa, Rosa beggeriana Schrenk and same kind of but different location Rosa spinosissima grown in Bayburt from Turkey are studied. The wild species of Rosa L. were collected from Rocks and Steps, Field and garden borders. Morphological parameters were measured as fruit and seed weights and fruit and seed size. Ten fruits were chosen randomly for the measurement and take the average of them to determine the weights and size. In our study was determined antioxidant activity, antimicrobial activity and phenolic compounds. As antioxidant activity; total phenolic total flavonoid, condense tannin contents, CUPRAC, FRAP, ABTS. Nineteen standard of phenolic compositions of fruits and seeds were determined. Antioxidant, antimicrobial activities of the extracts were found high levels in rose hip species fruit than seed. Catechin, rutin protocatequic acid and CAPE were principal for all rose hip species fruit but, was not deteceted CAPE Kop Mountain, Yukari Kop Village Rosa spinosissima species. This suggests that the difference in location affects the phenolic content. Pearson Correlation analyze has done with the morphological parameters, GPS data, antioxidant activity and phenolic compounds by using the SPSS software programme version 25.0.
AtıfWoS3İncele
