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- MakaleAçık Erişim2021Production and characterization of zinc oxide nanoparticles in microsystems via green synthesis; [Yeşil sentez yoluyla mikrosistemlerde çinko oksit nanopartiküllerin üretimi ve karakterizasyonu]
Akay, Şeref; Sefaoğlu, Melike
Nanoparticles (NP), which can be produced for many different fields and purposes; are at size vary from nanometer to a micrometer. These particles can be prepared by different approaches such as chemical, physical and biological methods. However, the biological approach is the most promising approach among other methods due to its simplicity and environmentally friendly conditions. The production of the nanoparticle by means of a biological approach does not require any high temperature, acidic/basic conditions and hazardous chemicals. Therefore, this method is named “green synthesis”. Development in microtechnology has had profound effects in many areas such as drug discovery, biology, diagnosis, and tissue engineering. Microfluidics which focuses on the processing of liquids in microscale systems has attracted wide attention in the production process of nanoparticles due to precise control and fast mixing. The main purpose of this study is to produce and characterize metal nanoparticles by combining microsystems and green synthesis approaches. For this purpose, in the first step, the design of microsystems that suitable for the flow of different phases was performed. In the second step, ZnO nanoparticle synthesis was carried out using the red cabbage (Brassica oleracea var.capitata f. Rubra) extracts. The synthesis of nanoparticles achieved by optimizing different parameters such as; extract: zinc ratio, zinc solution concentration, flow rates, and flow rates ratio in the microsystem and temperature. The results showed that the herbal red cabbage components can be used for the green synthesis of ZnO nanoparticles.
AtıfScopus1OpenAlex2TR Dizin1
İncele - MakaleYalnız künye2020Scopus SJRQ3Food label reading habits of health sciences students
Odaman, Tayyibe Ayşe; Bahar, Rabia; Şam, Sedanur; Ilyasoğlu, Huri
Purpose: The purpose of this study is to determine the food label reading habits of health sciences students. Design/methodology/approach: The data were collected through a face-to-face survey with voluntary students (n: 520). The survey questionnaire consisted of three parts to gather information about their demographic and anthropometric characteristics and food label reading habits. Chi-squared test and Pearson correlation analysis were used to analyze the data. Findings: The health sciences students mostly read the food name, expiration date and ingredients on the food labels. However, they paid less attention to the nutrient contents, such as the fat type and carbohydrate, cholesterol, sugar, fiber and salt amounts. The female students paid more attention to the nutrient contents than the male students. Moreover, the Nutrition and Dietetics students paid more attention to the nutrient contents than the other students. Significant negative correlations were found between the carbohydrate, protein and fat amount reading habits and both the body mass index (p = 0.005, p = 0.001 and p < 0.001) and waist to height ratio (p = 0.040, p = 0.005 and p = 0.022). Research limitations/implications: This study does not allow one to draw conclusions for all university students. Originality/value: This study is first such study performed among health sciences students in Turkey.
AtıfScopus7WoS7OpenAlex8
İncele - MakaleYalnız künye2021Scopus SJRQ1Single-step recovery of pectin and essential oil from lemon waste by ohmic heating assisted extraction/hydrodistillation: A multi-response optimization study
Tunç, Merve Tuğçe; Odabaş, Halil İbrahim
The main products obtained from citrus wastes are pectin and essential oil. In this work, ohmic heating assisted extraction/hydrodistillation (OHAE/H) was applied for the simultaneous recovery of pectin and essential oil from lemon waste. Optimum OHAE/H conditions to maximize the yield of pectin and essential oil were determined with response surface methodology. Three independent variables, namely liquid to solid ratio (w:v), extraction/hydrodistillation time (min) and voltage gradient (V/cm) were varied to obtain maximum pectin and essential oil yield. Optimum OHAE/H conditions were determined as 8.7:1 liquid to solid ratio, 58.4 min extraction/hydrodistillation time and 14.2 V/cm voltage gradient. The predicted pectin and essential oil yields at optimum conditions were 16.58 and 3.62 g/100 g lemon waste, respectively. Data analysis showed that all of the independent variables significantly affected the pectin and essential oil yield. In the verification study, close agreement was found between predicted and experimental values. Conventional heating extraction/hydrodistillation (CHE/H) were conducted to evaluate the effectivity of OHAE/H. With OHAE/H process, the yields of the pectin and essential oil were significantly increased when compared to CHE/H. Limonene concentration of the essential oil produced with OHAE/H was higher than the essential oil produced by CHE/H. Results demonstrate that the single-step OHAE/H could be an effective method for simultaneous extraction and hydrodistillation of pectin and essential oils.
AtıfScopus53WoS43OpenAlex54İncele - MakaleAçık Erişim2021Scopus SJRQ4Automatic Classification of COVID-19 using CT-Scan Images
Reis, Hatice Catal
Medicine and engineering sciences have been working in close contact for common purposes. Machine learning algorithms are used in the medical field for early diagnosis prediction. The major aim of this study is to evaluate machine learning algorithms and deep learning algorithms using computed tomography scan (CT-scan) images for automated detection of the coronavirus disease 2019 (COVID-19) patients. We obtained seven hundred and fifty-seven (757) CT-scan images from a public platform. We applied four automated traditional classification methods to predict COVID-19 using deep learning and machine learning. These algorithms are SVM, AdaBoost, NASNetMobile, and InceptionV3. Comparative analyses are presented among the four models by considering metric performance factors to find the best model. The results show that the InceptionV3 model achieves better performance in terms of accuracy, precision, recall, Cohen’s kappa, F1-score, root mean squared error (RMSE), and receiver operating characteristic-area under the curve (ROC-AUC), in comparison with the other Covid-19 classifiers. Accordingly, the InceptionV3 approach is recommended for the automatic diagnosis of Covid-19 and assessments. This research can present a second point of view to medical experts and it can save time for researchers as the performance of standard machine learning methods in detecting COVID-19 is evaluated.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2022Scopus SJRQ4DYNAMICAL ANALYSIS OF THE CONFORMABLE FRACTIONAL ORDER HOST-PARASITE MODEL
Şişman, Şeyma; Merdan, Mehmet
In this study, the differential equation system with a mathematical model of parasites is examined in cases where infection does not depend on transmission and defense, but on the level of infectivity and defense of the parasite and host. When discretization is applied to the differential equation, a two-dimensional discrete system is obtained in the range of t ∈ [n, n + 1] then the stability of the Neimark-Sacker bifurcation of the positive equilibrium point of this discrete system is investigated. Finally, MAPLE and MATLAB package program are used to show the accuracy of the results obtained.
- Kitap BölümüYalnız künye2020From bureaucracy to governance: Transition from centralism to localism in public administration
Cakir, Canan
- BildiriYalnız künye2021Stability estimates for a third order of accuracy difference scheme elliptic overdetermined multi-point problem
Ashyralyyev, Charyyar; Akyuz, Gulzipa
In this work, we discuss a third order of accuracy difference scheme for approximate solution of the elliptic overdetermined multi-point problem in the Hilbert space. Functional operator approach is used to study existence and uniqueness of solution of difference problem. Stability, almost coercive stability and coercive stability estimates for solution of difference scheme are established.
- MakaleAçık Erişim2021Scopus SJRQ4Evaluation of added sugar and sugar-sweetened beverage consumption by university students
Meric, Çağdaş Salih; Ayhan, Nurcan Yabanci; Yilmaz, Hacı Ömer
Today, increased intake of sugar and sugar-sweetened beverages is seen as an important factor in the growing prevalence of chronic diseases, such as obesity, obesity-related diabetes, and coronary heart diseases. This study involved 214 Ankara University students from the Department of Nutrition and Dietetics, which was intended to evaluate the consumption of sugar and sugar-sweetened beverages. The frequency of student consumption of beverages and the quantities and amounts of sugar taken with beverages were questioned. The average total amount of sugar added to drinks by the students was 4.69 ± 6.35 gram, while the average total amount of sugar taken with sugar-sweetened beverages was 11.34 ± 15.32 gram. Female students relative to male students, students in grade 4 compared to grades 2 and 3, and students who had daily breakfast compared to those who did not had lower average sugar consumption (p-value < 0.05). As class grades increase, the amount of sugar added to beverages and fruit juice and sweetened soft drinks and carbonated beverages decreased (p-value < 0.05). The consumption of herbal teas and dietary beverages increased and the eating habits of students generally changed positively (p-value > 0.05). It is important to educate university students about the reduction in sugar intake and sugar-containing food in order to avoid many chronic diseases that may be seen in older ages.
AtıfScopus6WoS5OpenAlex7İncele - MakaleYalnız künye2020Scopus SJRQ1Evaluating the feasibility of blockchain in logistics operations: A decision framework
Ar, Ilker Murat; Erol, Ismail; Peker, Iskender; Ozdemir, Ali Ihsan; Medeni, Tunc Durmus; Medeni, Ihsan Tolga
The main purpose of this study is to investigate the feasibility of blockchain technology in logistics industry using a quantitative approach. To this end, a decision framework is proposed based on a multi-criteria decision structure that incorporates AHP into VIKOR under Intuitionistic Fuzzy Theory. This integration presents different solutions and rankings based on different decision-making strategies and also captures uncertainty in the evaluation process. While Intuitionistic Fuzzy AHP calculates the importance weights of the proposed criteria indicated as scalability, privacy, interoperability, audit, latency, visibility, trust, and security, Fuzzy VIKOR ranks the logistics operations demonstrated as materials handling, warehousing, order processing, transportation, packaging, fleet management, labeling, vehicle routing and product returns management. The proposed decision framework was applied in a large-scale logistics company located in Turkey. The findings of this study suggest that while the most important criteria are security, visibility and audit, the most feasible logistics operations proved to be transportation, materials handling, warehousing, order processing and fleet management in a possible blockchain implementation. The decision framework in this study may enable decision makers to evaluate the feasibility of blockchain in logistics operations, which is one of the main research gaps in the current blockchain research. Furthermore, this is the first study that integrates AHP and VIKOR methods under Intuitionistic Fuzzy Theory in the context of blockchain.
AtıfScopus138WoS106OpenAlex145İncele - MakaleYalnız künye2021Scopus SJRQ2ReCRNet: a deep residual network for crack detection in historical buildings
Reis, Hatice Catal; Khoshelham, Kourosh
In historical buildings, surface cracks are important indicators of potential structural damage. Natural disasters and indirect human factors, which are frequently encountered in recent periods, negatively affect historical buildings and structures. Fast and cost-effective crack detection methods play a key role in structural health monitoring of historical buildings. This paper presents methodologies for identifying concrete cracks using deep learning. We propose ReCRNet, a deep learning architecture designed for classifying images of cracks. The performance of the proposed method is evaluated and compared with state-of-the-art methods such as AlexNet, VGG 19, linear support vector machine (SVM), and decision tree (DT). The results show that ReCRNet achieves better performance in terms of accuracy, precision, recall, F1-score, and receiver operating characteristic (ROC), in comparison with the other crack classifiers. Accordingly, the proposed approach is recommended for automatic monitoring of historical buildings and building condition assessments.
AtıfScopus17OpenAlex15İncele - MakaleAçık Erişim2020Scopus SJRQ3Educating children through their parents to prevent child sexual abuse in Turkey
Apaydın Cırık, Vildan; Efe, Emine; Velipaşaoğlu, Sevtap
Purpose: The aims of this study were to train parents to recognize and prevent child sexual abuse (CSA); evaluate the problems encountered by parents; and evaluate the overall effectiveness of the CSA training program. Design and Methods: The study used a pretest/posttest design. The study was conducted with a sample of 58 children (aged 3-6 years) and 64 parents. Findings: Children who received CSA prevention education from their parents demonstrated improved knowledge about private parts and about what they should do if they suspect sexual abuse. The parents stated that they encountered some problems (other family members objected to the child being given such training). Practise Implications: Children's risk of abuse may be reduced if their parents teach them about CSA correctly.
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İncele - MakaleYalnız künye2020Scopus SJRQ1A Neutrosophic VIKOR Method-Based Decision-Making with an Improved Distance Measure and Score Function: Case Study of Selection for Renewable Energy Alternatives
Eroğlu, Hasan; Şahin, Ridvan
In this study, a new score and distance function which provides more accurate results than the studies in the literature and considers the decision maker’s cognition has been proposed. In order to show the effects of the new score function coefficients on neutrosophic numbers, a new representation named “4D Plot” has been proposed. VIKOR (Vlse Kriterijumska Optimizacija Kompromisno Resenje which means multicriteria optimization and compromise solution in Serbian) method, which is based on the creation of a conciliatory solution within the framework of alternatives and evaluation criteria, provides highly effective results in multiple criteria decision-making problems. Neutrosophic numbers play an active role in facilitating the decision-making process in many studies. In this context, extension of the classical VIKOR method is introduced in detail in this study. The framework of the extended neutrosophic VIKOR method has been established. The proposed method has been applied to the renewable energy alternative selection problem in Turkey and compared with different methods and different scenarios. It has been shown that the proposed method gives more effective and accurate results. Furthermore, the sensitivity and accuracy of the study are enhanced by a sensitivity analysis. We have extended the classical VIKOR method for SVN numbers with a newly generalized score function and a distance measure. As a novel and newly presentation named “The 4D Plot” has been developed and applied in this paper to SVN numbers for presenting the effect of the new score function. The renewable energy alternative selection was made in Turkey with the proposed method by the opinions of the experts and the ranking of the alternatives was obtained. A sensitivity analysis has been made to show the accuracy and validity of the study. With the proposed distance measure and score function, it is shown that more accurate results can be found in multiple criteria decision-making problems. The model will provide solutions for many soft computing problems such as engineering and economy by finding more effective and accurate results in the neutrosophic number space according to the preference of decision makers. As a future work, the presented functions and framework can be adapted to different MCDM problems.
AtıfScopus50WoS35OpenAlex45İncele - MakaleAçık Erişim2020Scopus SJRQ3Excess lifetime cancer risk due to natural radioactivity in Gümüşhane Province, NE Turkey
Maden, Nafiz; Akaryali, Enver; Gücer, Mehmet Ali
In this study, 162 in situ measurements of 238U, 232Th, and 40K radionuclide concentrations dataset taken by the gamma-ray spectrometer in Gümüşhane, Turkey are presented. The gamma ray measurements were performed by a 512-channel, three-window gamma-ray spectrometry equipment made by GF Instruments. We first observed the radionuclides of the 238U,232Th, and 40K values in Gümüşhane. We then calculated the hazard indices of gamma radiation such as annual effective dose equivalent (AEDE), internal and external hazard index (Hin, Hex), and excess lifetime cancer risk (ELCR) based on the radionuclide abundances of 238U, 232Th, and 40K for the first time. In Gümüşhane, the average activity concentrations of radionuclides 238U, 232Th, and 40K were measured as 58.7 ± 34.3 Bq kg-1, 62.7 ± 37.2 Bq kg-1, and 1026.8 ± 486.0 Bq kg-1, respectively. The average outdoor annual effective dose equivalent and ELCR values were 132.2 ± 63.2 mSv yr-1 and 0.40 ± 0.19 × 10-3, respectively. Numerical results indicate that the radiological parameters (AEDE and ELCR) obtained for Gümüşhane Province were greater than the world’s mean values.
AtıfScopus7WoS7OpenAlex6İncele - MakaleAçık Erişim2020Scopus SJRQ2The Effect of the Fear of COVID-19 on Healthcare Professionals’ Psychological Adjustment Skills: Mediating Role of Experiential Avoidance and Psychological Resilience
Seçer, I; smail; Ulaş, Sümeyye; Karaman-Özlü, Zeynep
As the COVID-19 outbreak is rapidly spreading all over the world, it’s secondary consequences will negatively affect both societies and individuals. The target group, expected to be exposed to the secondary negative consequences most intensely during the pandemic process and afterward, is undoubtedly the healthcare professionals. In this research, the impact of the fear that healthcare professionals in Turkey developed against the outbreak of COVID-19 on their psychological adjustment skills is examined, and in this context, the mediating role of experiential avoidance and psychological resilience is examined. In this context, an answer was sought for the question “Does experiential avoidance and psychological resilience have a mediating role in the impact of COVID-19 fear on psychological adjustment skills of healthcare professionals?” The research was carried out with a total of 370 healthcare professionals reached via online data collection method. Structural equation modeling was used in the data analysis process, and as a result, it was determined that the fear of COVID-19 had a negative effect on the psychological adjustment in healthcare professionals; however, psychological resilience was found to have a protective function that limits this effect, and experiential avoidance has a risk factor that aggravates this effect. Findings obtained from the research are discussed in the context of the literature.
AtıfScopus54WoS47OpenAlex75İncele - MakaleAçık Erişim2022Scopus SJRQ2Determining the musculoskeletal problems of academicians who transitioned to distance education during the COVID-19 pandemic
Yorulmaz, Deniz S.; Karadeniz, Havva; Duran, Seçil; Çelik, İsa
BACKGROUND: Musculoskeletal disorders are a significant public health issue that negatively affects individuals and society both socially and economically, and increases the cost of care and cure. OBJECTIVE: This study aimed to determine the musculoskeletal problems and risk factors of academicians who transitioned to provide distance education during the COVID-19 pandemic. METHODS: The population of this descriptive cross-sectional study included academicians who worked in two public universities in Turkey. Ethical committee approval and institutional permissions were obtained between 1 and 28 February 2021. Data were collected using a personal information form, the Work Environment Evaluation Questionnaire, and the Musculoskeletal Pain Intensity Assessment Questionnaire. The data were analyzed using the number, percentage, independent group t-test, ANOVA test, and linear regression analysis (forward method). The analysis was interpreted at the 95% confidence level and 0.05 error margin. RESULTS: Of the academicians, 78% were women, 54.6% were married, 80.6% did not regularly exercise, and 73.5% had more workload during the distance education period. Academicians mostly experienced discomfort about their eyes, necks, and waists, and an increase at a significant level was detected in their musculoskeletal system problems during the distance education period. Increasing workload, duration of mobile phone use, active time, having an ergonomic chair, and gender predicted the musculoskeletal system pain intensity by 20%. CONCLUSION: Musculoskeletal system problems are a significant public health issue. Academicians should be informed and consulted for the protection of musculoskeletal system health during the distance education period.
AtıfScopus6WoS7OpenAlex7İncele - Kitap BölümüYalnız künye2021Impact of Covid-19 Pandemic on Cryptocurrency Prices
Karaaslan, İbrahim
- MakaleAçık Erişim2021Scopus SJRQ2Investigation of class 1 integrons with antibiotic resistance genes in multidrug-resistant acinetobacter baumannii strains and determination of plant extract effects on multidrug-resistant isolates
Saral, Ayşegül; Cinemre, Sedanur; Okumuş, Funda; Akar, Zeynep; Çiçek, Ayşegül Çopur; Düzgün, Azer Özad
This study aimed to investigate the presence of resistance genes in multidrug-resistant A. baumannii isolates as well as to determine the antibacterial activity of selected plant extracts against isolates. 41 strains were isolated from various clinical samples. PCR tests were performed using the primers. Methanol was used as solvent for the preparation of the plant extracts. MIC values of the plant extracts were determined by the broth microdilution method. The blaOXA-23, blaCTX-M-1, blaCTX-M-2, blaGES genes and Class 1 integrons were detected in five isolated strains. The lowest MIC value (2.25 mg/mL) was determined for the Echinacea purpurea extract, while the highest MIC value (50 mg/mL) was determined for the Morus alba extract. Determination of the antibacterial effect of plants extracts used in the study against A. baumannii isolates shows the importance of screening the antibacterial activity of plants in the fight against antibiotic resistance.
AtıfScopus1WoS1OpenAlex3İncele - MakaleYalnız künye2021Scopus SJRQ2Crustal Contamination of Tertiary Volcanic Rocks: Evidence from K, U, Th and Radiogenic Heat Production Data in Eastern Pontides (NE Turkey)
Maden, Nafiz; Akaryalı, Enver; Aydınçakır, Emre
Herein, we present new 238U, 232Th, and 40K radionuclide concentrations, density and radiogenic heat production (RHP) data on the Tertiary volcanic rocks outcropping in Borçka, Gumushane and Trabzon regions within the Eastern Pontide Orogenic Belt (EPOB). The mean K values for Trabzon, Borçka and Gümüşhane regions were 2.19 ± 0.87%, 0.90 ± 0.70% and 0.59 ± 0.25%, respectively, the mean U values for Trabzon, Borçka and Gümüşhane regions were 2.12 ± 0.76 ppm and 1.29 ± 0.68 ppm and 0.90 ± 0.32 ppm, and the average Th values were calculated as 6.54 ± 2.32 ppm, 2.49 ± 1.93 ppm and 1.33 ± 0.60 ppm for Trabzon, Borçka and Gümüşhane regions, respectively. The average Th/U values are 3.38 ± 1.48 for the Trabzon region, 2.01 ± 1.22 for the Borçka region, and 1.69 ± 1.09 for the Gümüşhane region. Average U/Th values were calculated as 0.35 ± 0.14, 0.71 ± 0.52 and 0.89 ± 0.72 for the Trabzon, Borçka and Gümüşhane regions, respectively. The RHP values were determined as 1.16 ± 0.35 μW m - 3, 0.58 ± 0.33 μW m - 3 and 0.37 ± 0.10 μW m - 3 for Trabzon, Borçka and Gümüşhane regions, respectively. The Tertiary aged rocks in the EPOB that we have examined within this study scope have been derived from an enriched mantle, previously metasomatized by fluids derived from subducted slab. The parental magma of Eocene basaltic rocks was contaminated with crustal material during the ascension of the magma through the crust or in the shallow-level crustal magma chambers.
AtıfScopus5WoS5OpenAlex6İncele - MakaleAçık Erişim2021Scopus SJRQ4Evaluation of Load-Transfer Efficiency of Steel Mesh Reinforced Contraction Joints in Concrete Pavement: Accelerated Pavement Test and FE Analysis
Celik, Muhammet; Seferoglu, Mehmet Tevfik; Akpinar, Muhammet Vefa; Nasery, Mohammad Manzoor; Seferoglu, Aysegul Gunes
Transverse contraction joints are by far the most common type of joint in jointed plain concrete pavements. Early loading of contraction joints can create a weakened vertical plane and later grow as a full-depth crack. In this study, load transfer efficiency (LTE) of steel mesh reinforced transverse contraction joints were studied at accelerated pavement tests (APT). 3D finite element (FE) model of jointed plain concrete pavement (JPCP) was developed to study deflections and crack propagation in just under the joint of the concrete pavement. The APT tests were focused on the LTE values before and after the crack initiation under the contraction joint region. Experiments were performed on three slabs in which two of these slabs were prepared without reinforcement and one of them was reinforced with steel mesh. Data generated by APT was used for verification of crack propagation modeling in the finite element analysis. Steel mesh reinforced slab gave the lowest vertical deflections (51μm) and highest LTE (91.56%). The LTE value in the reinforced slab after 25,000 passes was 13.63% higher than the average of unreinforced slabs. The findings suggest that the load transfer efficiency was found to be a complex parameter and should be interpreted together with average displacement values when contraction joints are evaluated at early traffic loadings.
AtıfScopus3WoS2OpenAlex2TR Dizin1İncele - MakaleYalnız künye2023Scopus SJRQ4Some special Smarandache ruled surfaces according to alternative frame in E3
Senyurt, Suleyman; Mazlum, Sumeyye Gur; Canli, Davut; Can, Elif
In this study ruled surfaces formed by alternative unit vectors that draw these curves along Smarandache curves obtained from alternative vectors and alternative unit Darboux vectors of a differentiable curve are defined. Then the Gaussian and mean curvatures of each ruled surface are computed. It is also examined whether the surfaces are developable or minimal. Finally, examples of these surfaces are given and their graphics are drawn.
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