Yayınlar
Koleksiyondaki öğeler
- BildiriYalnız künye2017Determination of the dynamic characteristics of the faculty building of engineering and natural science with hvsr method and fsr method
Beker, Y.; Sayıl, N.
Seismic response characteristics of structures can be estimated by spectral ratios of microtremors measured on structures and their foundation ground surface. The microtremor horizontal-to-vertical-spectral-ratio (HVSR) technique has received great attention from all over the world with its simplicity together with quick information about dynamic characteristics of ground and structures. The HVSR of microtremors gives a good estimation of natural building frequency. In this study, Nakamura (H/V) method and Floor Spectral Ratio Method (FSR) has been applied to microtremor records taken with three component broad band velocity seismometers in seven different locations inside the building (ground floor; east and west side for second, fourth and sixth floor) and one at outside with the aim of determining the dynamic characteristics of Faculty building of Engineering and Natural Science at Gumushane University, in NE Turkey. The average predominant frequency, period and amplification values for the Faculty building are calculated. The ratio of amplitude spectrum of the upper floors to amplitude spectrum of the ground floor for both of horizontal components (East-West, North-South) is determined using FSR Method. The vibration frequency and period is around 4.0 Hz and 0.332 s, respectively. Also, the damping ratio and vulnerability were calculated to the Faculty building.
AtıfScopus1
İncele - MakaleYayıncıda açık erişim2017Scopus SJRQ2Analysis of the changes in forest ecosystem functions, structure and composition in the Black Sea region of Turkey
Keleş, Sedat; Durusoy, İdris; Çakir, Günay
We used geographical information system to analyze changes in forest ecosystem functions, structure and composition in a typical department of forest management area consisting of four forest management planning units in Turkey. To assess these effects over a 25 year period we compiled data from three forest management plans that were made in 1986, 2001 and 2011. Temporal changes in forest ecosystem functions were estimated based on the three pillars of forest sustainability: economics, ecology and socio-culture. We assessed a few indicators such as land-use and forest cover, forest types, tree species, development stage, stand age classes, crown closure, growing stock and its increment, and timber biomass. The results of the case study suggested a shift in forest values away from economic values toward ecological and socio-cultural values over last two planning periods. Forest ecosystem structure improved, due mainly to increasing forest area, decreasing non-forest areas (especially in settlement and agricultural areas), forestation on forest openings, rehabilitation of degraded forests, conversion of even-aged forests to uneven-aged forests and conversion of coppice forests to high forests with greater growing stock increments. There were also favorable changes in forest management planning approaches.
AtıfScopus16WoS18OpenAlex21
İncele - MakaleAçık Erişim2019Scopus SJRQ3Reduced Akkermansia muciniphila and Faecalibacterium prausnitzii levels in the gut microbiota of children with allergic asthma
Demirci, M.; Tokman, H.B.; Uysal, H.K.; Demiryas, S.; Karakullukcu, A.; Saribas, S.; Cokugras, H.; Kocazeybek, B.S.
Introduction and objectives: The amounts of Akkermansia muciniphila and Faecalibacterium prausnitzii in gut microbiota are reduced in patients with allergic diseases compared to healthy controls. We aimed to quantify levels of A. muciniphila and F. prausnitzii amounts using real-time quantitative PCR (qPCR) in the gut microbiota of children with allergic asthma and in healthy controls. Materials and methods: In total, 92 children between the ages of three and eight who were diagnosed with asthma and 88 healthy children were included in the study and bacterial DNA was isolated from the stool samples using the stool DNA isolation Kit. qPCR assays were studied with the microbial DNA qPCR Kit for A. muciniphila and microbial DNA qPCR Kit for F. prausnitzii. Results: Both bacterial species showed a reduction in the patient group compared to healthy controls. A. muciniphila and F. prausnitzii were found to be 5.45 ± 0.004, 6.74 ± 0.01 and 5.71 ± 0.002, 7.28 ± 0.009 in the stool samples of the asthma and healthy control groups, respectively. Conclusions: F. prausnitzii and A. muciniphila may have induced anti-inflammatory cytokine IL-10 and prevented the secretion of pro-inflammatory cytokines like IL-12. These findings suggest that A. muciniphila and F. prausnitzii may suppress inflammation through its secreted metabolites.
AtıfScopus143WoS133OpenAlex149
İncele - MakaleYalnız künye2018Scopus SJRQ1Geometric optimization of an ejector for a 4 kW SOFC system with anode off-gas recycle
Genc, Omer; Toros, Serkan; Timurkutluk, Bora
One of the important energy saving tools used in solid oxide fuel cell (SOFC) system is the anode off-gas recycling (AGR) via an ejector which allows the recirculation of the unused fuels in the anode exhaust gas including hot steam which is essential for the elimination of the carbon deposition and the initiation of the reactions in the reformer. In an ejector system developed for the SOFCs, the steam to carbon ratio (STCR) and entrainment ratio are the crucial parameters for the determination of the ejector performance. These parameters can be engineered by modifying the geometric dimensions and operation conditions. This study focuses on the determination of the maximum STCR value and entrainment ratio via numerical geometric analyses for a micro combined heat and power (μ-CHP) system based on 4 kW SOFC, utilizing methane. A detailed numerical procedure for designing an ejector is provided and the ejector performance is investigated for different critical dimensions (throat diameter, nozzle exit angle and nozzle position etc.). The results show that the nozzle position and the nozzle exit angle significantly affect STCR and the entrainment ratio. When the nozzle position increases and nozzle exit angle decreases, the entrainment ratio and STCR is found to increase. The entrainment ratio and STCR are determined as around 7.3 and 2.7, respectively for a specific design created in the study.
AtıfScopus26WoS23OpenAlex24İncele - MakaleYalnız künye2018Scopus SJRQ4Volume calculation of brain structures in migraine disease by using mristudio
Palancı, Özgür; Kalaycıoğlu, Ahmet; Acer, Niyazi; Eyüpoğlu, İlker; Çakmak, Vildan A.
Migraine is a neurological disorder that is known as headache and accompanies attacks of neurological and gastrointestinal symptoms and prevents daily life activities of the person. In the literature, the volume changes of many structures in the brain have been investigated using brain magnetic resonance images (MRI) of migraine patients, but it has not yet been investigated whether there is a comprehensive and detailed volume change involving all the structures of the brain. The purpose of this study is to examine the brain structures in a wide range and to determine in which regions the volume changes. In this study, 25 healthy subjects and 25 migraine patients were included in the study. SPSS 15.0 program was used for statistical analysis. The Mristudio was used in our study when we examined the volumes of migraine patients and brain structures of healthy individuals. Statistically significant volume changes were found in the volumes of structures found in the brain frontal, parietal, occipital, temporal lobes. Volumetric changes were assessed in terms of duration of illness and frequency of attacks. In conclusion, our study is compatible with migraine pathophysiology. Structural changes in the brain are thought to be a risk factor for migraine. The evidence on the relationship of regional gray matter volumetric change detected in migraine is unclear. We believe that this ambiguity is caused by the method used.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2018Scopus SJRQ3Automated Model Updating Effect on the Linear and Nonlinear Dynamic Responses of Historical Masonry Structures
Altunişik, A.C.; Okur, F.Y.; Genç, A.F.; Günaydin, M.; Karahasan, O.
Finite element models supply the simulation of the problems to obtain the structural behaviors under different loading conditions. The updating processes based on changing the uncertain parameters such as material properties, boundary conditions, meshing size etc. are made to create actual finite element models in order to represent the real conditions of the problems. This procedure can be made using two methods, namely manual model updating and global/local automatic model updating. The global/local automatic model updating procedures are very popular owing to the applicability to all kind of engineering structures, minimizing the differences nearly to zero, availability of damage localization and structural health monitoring. In this paper a historical masonry armory building selected as an application and its finite element analyses, experimental measurements and automated model updating processes are carried out. The finite element model of the structures was developed with ANSYS software and first three natural frequencies are attained. The experimental dynamic characteristics such as natural frequencies, damping ratios and mode shapes are obtained using ambient vibration method. The differences between experimental and numerical frequencies are minimized up to the range of 0–1%, by using local updating procedure. The linear and nonlinear seismic analyses of the building are conducted on initial and updated models. At the end of the analyses, maximum displacements, principal stresses and strains are given with detail. In addition, crack distributions diagrams are attained to validate the stresses accumulation points. It can be seen that there is an increasing trend in the displacement, stress and strain values after finite element model updating both linear and nonlinear analysis. In addition, linear and nonlinear analysis results are compared with each other to evaluate the nonlinear analysis effect. It is concluded that the displacement and strain values are increased after nonlinear analysis. But, there is not any agreement in stress values.
AtıfScopus17WoS15OpenAlex15İncele - MakaleAçık Erişim2017Scopus SJRQ1Long term outdoor performances of three different on-grid PV arrays in central Anatolia – An extended analysis
Ozden, Talat; Akinoglu, Bulent G.; Turan, Rasit
Long term outdoor testing of the PV systems at different climatic conditions or different systems under the same ambient conditions are extremely important in producing policies for the transition to renewables. The present research is the testing of three different PV systems under the same climatic conditions of central Anatolia, after four years of operation. The systems consist of a mono-Si, an a-Si thin film and a CdTe thin film arrays. Different calculation procedures of the input solar irradiation on tilted surface are used for comparison. Performances together with degradation rates are computed using different procedures and also using the measured solar data of 20 km away from the installed systems. The accuracy is verified using 4 months of simultaneous measurements. The results showed that the aforementioned different input calculation procedures of the performances are important and determinant. The 44-months-average efficiencies of these three systems are calculated to be 11.86%, 6.40% and 5.30%, respectively. The degradation rates of these systems are obtained as 0.40%, 1.88% and 10.60%, respectively. Although the degradation rates that are calculated for the first two systems are quite similar to those appeared in the literature, CdTe system is considerably higher than those given in the literature.
AtıfScopus77WoS63OpenAlex76İncele - MakaleAçık Erişim2017Scopus SJRQ3The importance of amount of settlement in determining the bearing capacity of soils
Alemdaǧ, Selçuk; Cinoǧlu, Aslihan; Gacener, Elif
In this study, it is aimed to determine safe bearing capacity of soils, which are out cropped around Tamzi and Akcakale villages located in Gumushane, providing allowable settlement conditions for an optimum foundation design. To define the geotechnical properties of soils, three trenches were dug and two seismic refraction with two Multichannel Spectral Analysis of Surface Waves (MASW) were carried out in each research area. Sieve analyses, shear box tests, triaxial compression tests were carried out on disturbed and undisturbed samples taken from the trenches. Seismic velocities of the soils are determined by seismic refraction and MASW methods. While determining the safe bearing capacity; the equations proposed by Terzaghi, Meyerhof, Kurtuluş, Tezcan and Özdemir, Türker, Keçeli were used and the obtained safe bearing capacity values were compared to each other. After, the soils were modeled numerically by using finite elements method and safe bearing capacities providing allowable settlement conditions were determined. According to the results, safe bearing capacity values obtained from empirical equations are not satisfactory to have an optimum foundation design. For the optimum foundation design, safe bearing capacity should be accepted as 190 kN/m2 for clayey soil (CL) and 485 kN/m2 for the clayey sand (SC).
AtıfScopus1OpenAlex4İncele - MakaleYalnız künye2018Scopus SJRQ2An enhanced scanning-based MPPT approach for DMPPT systems
Başoğlu, Mustafa Engin
In this paper, an improved maximum power point tracking (MPPT) approach being low parameter dependency, simple structure and limited search interval has been presented for distributed MPPT photovoltaic (PV) systems. Basically, this approach is based on scanning of power–voltage (P-V) characteristic curve of PV modules in a limited duty ratio interval which makes tracking operation simple, fast and efficiently available in both uniform irradiance and partial shading conditions (PSCs). By limiting the scanning interval of maximum and minimum values of duty ratio via some analyses related to P-V characteristic for PSCs, global MPPT (GMPPT) is achieved in an efficient way. So as to validate performance of the proposed approach, a single-ended primary inductance converter has been used in both simulation and experimental studies. PV simulator has been used as a PV source to obtain different module characteristics with different number of bypass diodes and PV power levels. Both simulation and experimental results clarify that improved MPPT approach realises GMPPT effectively. Due to the high performance results, this approach can be an alternative technique in module-integrated converters, smart modules and PV power optimisers in which single module is used.
AtıfScopus27WoS23İncele - MakaleYalnız künye2016Scopus SJRQ3The Effect of Dy Doping on the Magnetic Behavior of YBCO Superconductors
Öztürk, Ali; Doğan, Mustafa; Düzgün, İbrahim; Çelebi, Selahattin
The effect of dysprosium (Dy) doping on yttrium barium copper oxide (YBCO) prepared by conventional solid-state reaction method has been investigated by means of XRD, AC susceptibility, and DC magnetization measurements. AC susceptibility measurements for sintered YBCO pellets have been performed as a function of temperatures at constant frequency and AC field amplitude in the absence of a DC bias field. DC magnetization measurements were done at 5, 20, and 77 K upon zero field cooling (ZFC) process. The magnetization measurements showed a paramagnetic behavior existing at high magnetic fields. The magnetic field dependence of critical current density of the samples has been estimated from DC magnetization data. The partial Dy substitution for Y on YBCO superconductors improves the bulk critical current density at high magnetic fields and at high-temperature regions (higher than 20 K).
AtıfScopus18WoS15OpenAlex16İncele - MakaleAçık Erişim2018Scopus SJRQ1Indoor and outdoor radon measurements at lung cancer patients’ homes in the dwellings of Rize Province in Turkey
Özen, Songül Akbulut; Celik, Necati; Dursun, Emrehan; Taskın, Halim
In this study, indoor and outdoor radon (222Rn) surveys were carried out in the summer and winter seasons in homes of one hundred lung cancer patients in the year 2013–2014. The aim was to investigate the relationship between radon and cancer patients. Lung cancer patients completed a questionnaire concerning their living environment, various physical parameters and living habits. Pearson correlation and t tests revealed no meaningful results between radon concentrations, on one hand, and environmental and personal living habits, on the other hand. Consequently, the BEIR VI model was adapted and 222Rn exposure was estimated to be responsible for about 12% of the lung cancer incidences in the winter season and around 5% in the summer season in the Rize Province. However, due to the limited number of data and numerous parameters that could lead to lung cancer, the estimations done with the model should be taken very lightly. The annual effective doses due to inhalation of indoor and outdoor 222Rn were estimated to be, respectively, 1.43 and 0.94 mSv y−1. The indoor and outdoor annual effective doses were, respectively, close and below the world annual effective dose (1.3 mSv y−1). At the district level, the indoor annual effective dose equivalent in the İyidere district was 4.52 mSv y−1, which was 3.5 times greater than the world average. The number of patients in the majority of the houses in this district was more than one.
AtıfScopus31WoS27OpenAlex33İncele - MakaleYalnız künye2021Scopus SJRQ4Gynecological Cancer Awareness Among Women
Özcan, Handan; Demir Doğan, Melike
Purpose: The purpose of this study is to evaluate and determine the gynecological cancer awareness among women aged 20 and over and make recommendations according to the current situation. Method: The study is a quantitative, descriptive, and cross-sectional study. The population of the study was composed of a total of 60.290 women aged over 20 years living in the city center of Gumushane according to TURKSTAT data for 2017. The sample consisted of a total of 382 women determined at 95% confidence interval. Personal information form and Gynecological Cancer Awareness Scale were used to collect the data. Results: The mean age of the women was 39.07 ± 17.84. 48.6% of the participants had knowledge about gynecological cancers, and only 16.2% reached this information from healthcare personnel. It was determined that the women who were working, had an employed husband, had a high level of education, had a husband with high level of education, had no chronic disease, and had knowledge about gynecologic cancers were higher than the others. The awareness of the participants about gynecological cancer decreased as their ages, body mass index, the number of pregnancy and birth increased. The gynecological cancer awareness of the women increased with the increase in marriage age, the age of first sexual intercourse, and the age of first pregnancy. Conclusion: Early diagnosis of gynecological cancers with effective and common screening programs is very important in reducing mortality and morbidity rates. It is recommended to maintain healthy lifestyle behaviors, avoid risky behaviors, screen risky groups and ensure women’s awareness for primary prevention.
AtıfScopus19WoS20OpenAlex24İncele - MakaleYalnız künye2020Scopus SJRQ4Effect of concentration and drying processes on physical and chemical properties of strawberry {arbutus unedo l.) leather (pestil)
Kerse, Sevgi; Okcu, Zuhal
In this study, producting with different concentration of starch (%5 ve %8) and different dried methods (in drying oven 60 °C, 80 °C, microwave oven and conventional drying methods arbutus leather is analysed in terms of physical, chemical and sensory parameters. Fruit is more ascorbic acid, total phenolic, antioxidant activity than other leathers. Fruit leathers which contain %8 starch, values are high than leather produced in different concentratioas exclusive HMF value. Fruit leather which dried conventional methods has high value of total dry matter, water soluble dry matter, total sugar, invert sugar,sucrose, ascorbic acid and ABTS values. Fruit leather which dried in micro waveoven has highvalue of ash, total phenolic, DPPH and HMF value. Leathers, which is most appreciated in sensory evaluation, is pestil dried at 60 °C.The least appreciated was the microwave-dried leather.
- MakaleAçık Erişim2020Scopus SJRQ2Response of Japanese quails (Coturnix coturnix japonica) to dietary inclusion of Moringa oleifera essential oil under heat stress condition
Tekce, Emre; Bayraktar, Bülent; Aksakal, Vecihi; Dertli, Enes; Kamiloğlu, Aybike; Çinar Topcu, Kübra; Takma, Çiğdem; Gül, Mehmet; Kaya, Hacer
The present study was aimed at investigating the effects of the dietary use of different doses of Moringa oleifera essential oil (MOEO) on performance parameters, internal organ weights and meat quality in Japanese quails (Coturnix coturnix japonica) exposed to Heat Stress (HS). For this purpose, 320 male day-old quail chicks were used. Seven days of preliminary (physical exercise) and a 35-day fattening period were applied. The animals were divided into 8 groups, each including 40 animals according to temparature (C: 25 °C and SC: 37 °C) and dietary doses (C, 200, 400 and 600). Each group was divided into 4 subgroups, each comprising 10 animals. The consequences of this study showed that, in the stress-free (HSF) groups, while all of the different doses of dietary MOEO positively affected growth performance, feed intake and feed efficiency, in the HS groups, similar positive effects were observed with the use of 200 ppm of dietary MOEO. While no effect was detected on internal organ weights on Days 21 and 42 in the HSF and HS groups, a dose-dependent increase was determined in the intestinal pH value on day 42 in the HS group (p <.05). Additionally, in the analysis of meat quality on the 21st and 42 days compared to the controls, no effect was observed on the meat colour parameters value and TBARS level in the HS and HSF groups. Based on the consequences of this study, it is considered that, MOEO could be used as an alternative product in poultry, at a dose of 200 ppm, to reduce the detrimental effects of HS.HIGHLIGHTS Temperature stress, performance parameters and serious problems in the health of poultry. Moringa olifera helps regulate performance parameters in poultry exposed to heat stress. Since the addition of Moringa oleifera to the diets does not affect the organ weight and meat quality in 21 and 42 days, it does not cause any negative effects for the consumer.
AtıfScopus17WoS17OpenAlex19İncele - MakaleAçık Erişim2021Scopus SJRQ1Effect of heat treatment on mechanical and wear properties of Zn–40Al–2Cu–2Si alloy
SAVAŞKAN, Temel; AZAKLI, Zeki; HEKÌMOĞLU, Ali Paşa
In order to determine the effect of heat treatment on the mechanical and wear properties of Zn–40Al– 2Cu–2Si alloy, different heat treatments including homogenization followed by air-cooling (H1), homogenization followed by furnace-cooling (H2), stabilization (T5) and quench–aging (T6 and T7) were applied. The effects of these heat treatments on the mechanical and tribological properties of the alloy were studied by metallography and, mechanical and wear tests in comparison with SAE 65 bronze. The wear tests were performed using a block on cylinder type test apparatus. The hardness, tensile strength and compressive strength of the alloy increase by the application of H1 and T6 heat treatments, and all the heat treatments except T6, increase its elongation to fracture. H1, T5 and T6 heat treatments cause a reduction in friction coefficient and wear volume of the alloy. However, this alloy exhibits the lowest friction coefficient and wear volume after T6 heat treatment. Therefore, T6 heat treatment appears to be the best process for the lubricated tribological applications of this alloy at a pressure of 14 MPa. However, Zn–40Al–2Cu–2Si alloy in the as-cast and heat-treated conditions shows lower wear loss or higher wear resistance than the bronze.
AtıfScopus17WoS14OpenAlex18İncele - MakaleYalnız künye2020Scopus SJRQ2Numerical and Experimental Investigation on the Effects of a Nozzle Attachment to Plasma Torches for Plasma Atomization
Yurtkuran, Emre; Ünal, Rahmi
Plasma atomization technology is able to both melt and atomize a material which is fed into the converging plasma jets as a wire. Temperature and velocity distribution in a plasma jet obtained at the outer region of a plasma torch is very important to melt a solid wire and to disintegrate the liquid metal into fine spherical particles. In this study, a non-transferred arc plasma torch is designed and numerically solved for the determination of temperature and velocity distributions in the plasma jet. A high velocity nozzle attachment is assembled to plasma torches for increasing the jet velocity for atomization purposes. Results of numerical solutions with and without high velocity nozzle attachment are discussed and compared with experimental studies. It is found that high velocity nozzle attachment can be favourable in terms of the higher velocity and temperature distribution in the plasma jet at longer distances from the torch exit.
AtıfScopus22WoS21OpenAlex22İncele - MakaleYalnız künye2016Scopus SJRQ3A research on instıtutıonal socıal responsıbılıty projects executed in the matter of educatıon
Çalişir, Gülsüm
Together with developing world, needs, charges and responsibilities also are changing. At the age we are in holdings, enterprises, corporations and organisations had become charged to do community oriented works now. In this regard, those mentioned units had transformed to state that they felt themselves responsible to give they took from people to people again. Corporations especially had tended towards social responsibility stusies to be able to addres their target groups before societ within the context of public relations activities and to establish a bridge in between. As change in time also cause change in expectations, now corporations had concentrated on social responsibility studies to be able to be approved in society and to continue their existing prestiges, instead of contenting teirselves just with commercial activities. Thus, also the importance of the concept called institutional social responsibility had increased in the century we live. Within this frame, to research efforts made in social responsibility studies executed in the area of “education” is forming the subject of this study. From the point of view of mentioned notion, a sample had been formed through coincidental choice of ten of institutions becoming prominent in society in this study. According to the research done through web sites of these ten institutions included the sample, examples to the studies institutions executed in educational area had been given by telling their institutional social responsibility understandings and policies, and their contents had been tried to be expressed. While existance of institutional social responsibility policies in six institutions included the study had been drawing attention, it had been determined that Business Bank of Turkey’s (Türkiye İş Bankası) and Turkcell’s institutional social responsibility activities accomplished in educational area were more different than the other eight institution and realized in areas more than one.
- MakaleAçık Erişim2022Scopus SJRQ1Highly siderophile element and Os isotope systematics of the Cenozoic volcanic rocks from the Eastern Pontides, NE Turkey: Constraints on the origin and evolution of subcontinental mantle-derived magmas
Arslan, Mehmet; Temizel, İrfan; Ackerman, Lukáš; Yücel, Cem; Yazar, Emel Abdioğlu
The Cenozoic subalkaline to alkaline volcanic rocks from the Eastern Pontides Orogenic Belt (EPOB) in NE Turkey exhibit wide range of highly siderophile element (HSE) contents and Os isotope compositions that can be related to their mantle sources and parental melt evolution. Although some Eocene rocks show signs of late-stage modification, most of the studied volcanic rocks possess primary HSE and Os systematics. The Eocene volcanic rocks have largely variable PdN/IrN (~0.25–751), PdN/PtN (~0.25–87) and (187Os/188Os)i ratios (~0.113 to 0.51). The Miocene volcanic rocks have high PdN/IrN (~2.6–441), low PdN/PtN (~0.11–1.7) and radiogenic (187Os/188Os)i ratios ranging from ~0.166 to 0.52 while the Mio-Pliocene volcanic rocks show high PdN/IrN of ~7.2–29, low PdN/PtN (~1.2–2.7), and only mildly radiogenic (187Os/188Os)i values between ~0.132 and 0.177. Finally, the Quaternary volcanic rocks have low PdN/IrN (~2.3–3.6), PdN/PtN (~0.9–1.6) and radiogenic (187Os/188Os)i values ranging from ~0.133 to 0.194. Overall, the primitive mantle-normalized HSE patterns of the studied volcanic rocks are characterized by PPGE (Pt, Pd) and Re enrichment with respect to IPGE (Os, Ir, Ru). The variations in HSE and radiogenic Os isotope compositions of the relatively differentiated volcanic rocks indicate that crustal assimilation played active role in their parental melt evolution, especially in the Eocene and Miocene period. Besides, the obtained HSE data also suggest that the parental magmas of all the studied volcanic rocks were generated mainly in the S-saturated conditions. The temporal and spatial HSE and Os isotope variations observed in the studied Cenozoic volcanic rocks reflect the heterogeneity of the mantle source beneath the EPOB, which could be attributed to variations in response of different fluid/melt metasomatism of the underlying SCLM.
AtıfScopus12WoS11OpenAlex10İncele - MakaleYalnız künye2022Scopus SJRQ2An Investigation of the Antiproliferative Effect of Rhododendron luteum Extract on Cervical Cancer (HeLa) Cells via Nrf2 Signaling Pathway
Turan, Ibrahim; Demir, Selim; Yaman, Serap Ozer; Canbolat, Deniz; Mentese, Ahmet; Aliyazicioglu, Yuksel
The aim of the present study was to investigate the role of Rhododendron luteum extract (RLE) in the induction of Nrf2‑related oxidative stress and endoplasmic reticulum (ER) stress in human cervical cancer (HeLa) cells. The antiproliferative effect of RLE on HeLa and fibroblast cells was determined using the MTT assay. The effects of RLE on the cell cycle, apoptosis, and production of reactive oxygen species (ROS) in HeLa cells were evaluated using fluorescent probes. The mRNA expression levels of Nrf2 [and its targets glutamate-cysteine ligase catalytic subunit (GCLC), and glucose-6-phosphate dehydrogenase (G6PD)], and C/EBP homologous protein (CHOP, an ER stress marker were determined using reverse transcription‑quantitative polymerase chain reaction (RT-PCR). The results demonstrated that RLE exhibited a selective cytotoxic effect (2.9-fold) on HeLa cells compared to fibroblast cells. RLE arrested the cell cycle at the S phase, and induced apoptosis, ER stress, and ROS formation. In addition, RLE significantly suppressed the expression levels of Nrf2, GCLC and G6PD (0.65, 0.69, and 0.54-fold, respectively) and increased the expression of CHOP (4.48-fold) in HeLa cells at 72 h of treatment (p < 0.05). These results show that the antiproliferative effect of RLE occurs through the Nrf2 and ER stress pathways, and the results should now be supported by further in vivo studies.
AtıfScopus15WoS15OpenAlex13İncele - MakaleYalnız künye2022Scopus SJRQ3The relationship between banks’ credit quality, credit growth and social capital: evidence from Turkish banking sector
Pilatin, Abdulmuttalip; Ayaydin, Hasan
The aim of this study is to empirically examine the relationship between credit growth, credit quality and social capital of all commercial banks operating in Turkey for a period of twelve years between 2007 and 2018 on the basis of 81 provinces. In order to measure social capital on a provincial basis, the independent variable SC1 was obtained by applying principal component analysis to the variables consisting of 2 network and 2 norm variables. In addition, province-based organ donation rate was used as an alternative social capital variable. Changes in Total Loans (ΔTL), Changes in Real Estate Loans (ΔREL), Changes in Commercial and Industrial Loans (ΔCIL), Changes in Construction Loans (ΔCL), Changes in Non-Performing Loans (ΔNPL), Ratio of Non-Performing Loans to Total Loans (NPL/TL) and Ratio of Non-Performing Loans to Total Assets (NPL/TA) were determined as the dependent variable. The relationship between the level of social capital (SC1) and seven dependent variables on a provincial basis in Turkey was analyzed and measured using panel data techniques. The results of the analysis show that the relationship between the social capital level of the provinces, credit growth and non-performing loans are negative and significant. The results of the study show that the level of social capital is important and decisive in terms of credit growth and credit risk of banks.
AtıfScopus6WoS7OpenAlex12İncele
