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Koleksiyondaki öğeler
- MakaleAçık Erişim2023Scopus SJRQ2Extraction of Functional Compounds from Tarragon (Artemisia dracunculus L.) by Deep Eutectic Solvents at Different Properties
Can Gerçek, Yusuf; Kutlu, Naciye; Çelik, Saffet; Gıdık, Betül; Bayram, Sinan; Bayram, Nesrin Ecem
In this study, it was aimed to examine the capacity of deep eutectic solvents (DESs) with different contents to extract bioactive compounds from tarragon (Artemisia dracunculus L.) plant. For this reason, the total phenolic-flavonoid content, total proanthocyanidin content and antioxidant/antimicrobial activities of the prepared DES extracts were investigated, as well as the individual phenolic and individual amino acid profiles. According to the results, DES10 had the highest efficiency in terms of its capacity to extract individual phenolics (approximately 59 mg/100 g) and individual amino acids (approximately 2500 mg/kg), and also gave a higher yield compared to ethanol (approximately 44 mg/100 g for individual phenolics and about 19810 mg/kg for individual amino acids) and methanol (approximately 58 mg/100 g for individual phenolics and approximately 21430 mg/kg for individual amino acids). However, the total phenolic content, total flavonoid content and antioxidant activity values of DES extracts were determined between 59.09–77.50 mg GAE/100 g, 28.68–45.55 mg GAE/100 g and 42.96–146.86 mg TE/100 g, respectively. Therefore, it can be recommended to use these green solvents, which are known as environmentally friendly, as an alternative to organic solvents in the process of preparing extracts of this important medicinal plant in different areas.
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İncele - Kitap BölümüAçık Erişim2023Trajectory Tracking Control of an Unmanned Ground Vehicle Based on Fractional Order Terminal Sliding Mode Controller
Sekban, Hayriye Tuğba; Başçi, Abdullah
In this chapter, fractional order terminal sliding mode control (FOTSMC) method, which is a hybrid control approach, is used to improve the trajectory tracking control performance of an unmanned ground vehicle (UGV). First, a kinematic controller design has been carried out to estimate the linear and angular velocities that will stabilize the vehicle asymptotically. Then, FOTSMC, which is a hybrid control method that combines the advantages of fractional control and terminal sliding mode control methods, is proposed to perform vehicle reference velocities tracking. In addition, terminal sliding mode control (TSMC) and sliding mode control (SMC) methods are used for trajectory tracking control of the same vehicle to demonstrate the performance of the proposed controller. Simulation results show that the proposed controller performs trajectory tracking with smaller error and lower amplitude chattering compared to TSMC and SMC.
- MakaleYalnız künye2025Scopus SJRQ2A novel exopolysaccharide from cold-adapted yeast Rhodotorula glutinis, along with structural, rheological, antioxidant, and antibiofilm properties
Oztekin, Sebahat; Dikmetas, Dilara Nur; Karbancıoglu-Guler, Funda
In the present study, a novel exopolysaccharide EPS-BMD26 produced by cold-adapted yeast Rhodotorula glutinis was structurally examined, along with its rheological, antioxidant, and antibiofilm properties. High-performance liquid chromatography (HPLC) analysis revealed glucose and galactose as two monosaccharide constituents. The functional groups within the EPS-BMD26 structure were detected by Fourier transform infrared (FT-IR) spectroscopy. The 1H and 13C nuclear magnetic resonance (NMR) spectra of EPS-BMD26 also confirmed its β-D-glucan type with galactose residues with an average molecular weight of 118 kDa. Differential scanning calorimetry (DSC) analysis revealed that EPS-BMD26 had a high level of thermal stability, up to 326.16 °C. Scanning electron microscopy (SEM) analysis demonstrated that EPS-BMD26 had a porous microstructure with fissures. X-ray diffraction (XRD) analysis revealed its semi-crystalline nature. EPS-BMD26 showed moderate and concentration-dependent antioxidant potential recruiting different methods, including •OH, DPPH•, CUPRAC, and ABTS radical scavenging activities. Water-soluble EPS-BMD26 exhibited high water holding capacity of 190 ± 0.22% with a water solubility index of 60.6 ± 8.3%. At 1.25 mg mL-1, EPS-BMD26 inhibited biofilm formation of Staphylococcus aureus ATCC 25923 by 79.5%. Rheological characterization revealed that the aqueous solution of EPS-BMD26 had shear thinning and pseudoplastic behavior. Given these properties, EPS-BMD26 may be a promising bio-hydrocolloid, antibiofilm agent, and food additive for industrial applications.
AtıfScopus15WoS15OpenAlex17İncele - MakaleAçık Erişim2023Scopus SJRQ2Investigation of organic and inorganic matters removal from tannery wastewater using iron plate electrode by electrocoagulation process
Bingül, Züleyha; Irdemez, Şahset; Kul, Sinan; Ekmekyapar Torun, Fatma; Demircioğlu, Nuhi
In this study, COD, turbidity, total nitrogen, phosphate, sulphate, oil-grease and chromium removals from wastewaters taken from a local tannery using the electrocoagulation process were examined and the most suitable parameters for the electrocoagulation system were tried to be determined. Soluble iron plate electrodes were used as electrodes in the experiments. As a result of the studies carried out, the most suitable initial pH in uncontrolled pH was determined as pH = 4 and for controlled pH as pH = 5. In studies, the most suitable current density for iron electrodes was determined as 1.2 mA cm−2. Even if the increase in current density increased the amount of dissolved Fe, it negatively affected the removal efficiency. In addition, the turbidity of the wastewater was removed in 30 minutes, phosphate in 20 minutes and chromium in 15 minutes by 100%. During 60 minutes of operation, while 62.91% of TN, 87.8% of oil-grease were removed, sulphate was removed at the rate of 54.78%. In the studies, 1st and 2nd order kinetic equations for COD removal were examined and it was determined that removal kinetic is more suitable for 2nd order kinetics.
AtıfScopus7WoS4İncele - MakaleAçık Erişim2023Scopus SJRQ2Experimental study of adhesively bonded joints with dissimilar composite laminates under different loading rates and ambient temperatures
Erbayrak, Engin; Gumus, Beril Eker; Yuncuoglu, Ercument Ugur
An experimental study of the single-lap joints at different loading rates and ambient temperatures was investigated. In the experiment, a single lap joint was formed using plain woven glass fiber reinforced epoxy (GFRE) laminates, plain woven aramid fiber reinforced laminates (AFRE), and Araldite 138 M / HV998 epoxy adhesive. The composite laminates were produced using Vacuum-Assisted Resin Transfer Molding (VARTM) process. Adhesively bonded joints were created using similar and dissimilar adherends. Experiments were carried out under different loading rates (1 mm/min, 10 mm/min, 50 mm/min, 100 mm/min) and ambient temperatures (23°C,60°C,100°C). Stress–strain graphs were obtained for each experimental condition. It is seen that the maximum stress values increase as the loading rate increases in all single lap joints at all different temperatures. However, in all single lap joints, at all different loading rates, the maximum stress value decreases as the ambient temperature increases.
AtıfScopus7WoS7OpenAlex7İncele - MakaleAçık Erişim2024Scopus SJRQ3The Effect of Computer-Supported Stem Applications on Secondary Students' Achievement and Computational Thinking Skills
Berk, Gizem; Gülcü, Aslan
In this study, the effect of STEM applications integrated with computer-supported materials on mathematics achievement in the subject of ratio-proportion and percentages was examined. In addition, it was aimed to reveal the effect of these applications on computational thinking skills. Furthermore, we aimed to reach the opinions of the experimental group students about the materials they used, STEM applications, and the application process. A mixed method was used with a sample consisting of 89 students in grade 7 of a secondary school. An achievement test, a scale of levels of computational thinking, and learning diaries were used as tools for data collection. The data were analyzed using t-test and content analysis. It was found that there was a significant difference between the experimental and control groups in terms of achievement in favor of the experimental groups. In terms of computational thinking, there was a significant difference in favor of the experimental groups, except for the creativity aspect of computational thinking skills. Based on the findings obtained with the computational thinking skills scale the study had a positive impact on most aspects of computational thinking. Accessed through the learning diaries students' views on learning with STEM applications were generally positive. In particular, the opinions on computer-supported materials pointed to a very satisfactory process. The findings suggest that the inclusion of STEM activities and the use of computer technology in education contribute to students' computational thinking skills and learning.
AtıfScopus2OpenAlex3İncele - MakaleAçık Erişim2025Scopus SJRQ1Investigation of the phonological awareness of A1 level students learning Turkish as a foreign language
Güngör, Haluk; Koçak, Aslı; Maden, Sedat
Phonological awareness is pivotal in language learning, influencing speaking, writing, and listening abilities. Identifying factors that affect reading development is crucial for effective language instruction. This study explores the phonological awareness of A1-level learners of Turkish as a foreign language (TFL), examining how native language backgrounds impact this foundational skill. Ninety-three participants, whose native languages include Arabic, Indonesian, French, Russian, and Kazakh, were assessed using the Phonological Awareness subtest from the Early Literacy Test (EROT). Data analysis employed non-parametric statistical methods, specifically the Mann-Whitney U and Kruskal-Wallis tests. Results revealed no statistically significant relationship between gender and phonological awareness, although female participants exhibited higher average scores than males. Among native language groups, Kazakh speakers achieved the highest phonological awareness scores, whereas Indonesian speakers scored the lowest. These findings indicate that a learner’s native language significantly influences their phonological awareness in Turkish. Despite its limited scope, this pilot study underscores the essential role of phonological awareness in developing comprehensive language skills in TFL learners. l.
- MakaleAçık Erişim2025Scopus SJRQ3Chemical composition of essential oils and comparative analysis of enzyme inhibitory, antioxidant and antimicrobial activities in essential oils of endemic Gelasia sericea (Aucher ex DC.) Zaika, Sukhor. & N. Kilian
Fidan, Muhammed Said; Baltacı, Cemalettin; Akmeşe, Osman; Sefalı, Abdurrahman; Aygül, İmdat; Öz, Mehmet
In this study, essential oil from the aerial parts of Gelasia sericea (Aucher ex DC.) Zaika, Sukhor. & N. Kilian was extracted via hydrodistillation using a Clevenger apparatus. GC-MS/FID analysis determined aldehydes (28.31%) as the dominant group, with eucalyptol (8.71%) as the main constituent. Antioxidant activities were exhibited using DPPH, ABTS, and FRAP assays, with the essential oil demonstrating relatively higher antioxidant properties. The essential oil also showed higher levels of bioactive components, including total antioxidant capacity (160.26 mg AA eq./100 mL), total phenolic content (21.57 mg GA eq./100 mL), and total flavonoid content (14.85 mg QE eq./100 mL). While G. sericea essential oil demonstrated some antioxidant activity, it was significantly lower compared to the reference standard ascorbic acid (AA). The antimicrobial results showed relatively higher antimicrobial activity compared to most bacterial and fungal strains, as evidenced by lower MIC and MBC values and larger inhibition zones. Nevertheless, chloramphenicol (CH) and nalidixic acid (NA) continually showed superior antimicrobial efficacy, with the lowest MIC and MBC values and the largest inhibition zones. The essential oil also demonstrated potent enzyme inhibitory activity, especially against CA-II, AChE, and BChE, with the lowest IC50 value observed for CA-II, highlighting its potential as a potent enzyme inhibitor. However, the essential oil exhibited comparatively greater inhibition against AChE, BChE and α-amylase but was less effective overall. These findings suggest that the G. sericea essential oil has important antioxidant potential and enzyme inhibitory activity, while the essential oil shows varying efficacy across different enzymes.
AtıfOpenAlex1İncele - MakaleAçık Erişim2023Scopus SJRQ3The effect of heart failure on gut microbial richness and diversity; [O efeito da insuficiência cardíaca estável na riqueza e diversidade microbiana intestinal]
Kilic, Oguz; Kaya, Halil Ibrahim; Secme, Mucahit; Kilinc, Mehmet; Sevgican, Cihan Ilyas; Buber, Ipek; Dodurga, Yavuz; Simsek, Omer; Ergin, Cagrı; Kilic, Ismail Dogu
Introduction and objective: With recent advances in genome sequencing technology, a large body of evidence has accumulated over the last few years linking alterations in microbiota with cardiovascular disease. In this study, we aimed to compare gut microbial composition using 16S ribosomal DNA (rDNA) sequencing techniques in patients with coronary artery disease (CAD) and stable heart failure (HF) with reduced ejection fraction and patients with CAD but with normal ejection fraction. We also studied the relationship between systemic inflammatory markers and microbial richness and diversity. Methods: A total of 40 patients (19 with HF and CAD, 21 with CAD but without HF) were included in the study. HF was defined as left ventricular ejection fraction <40%. Only stable ambulatory patients were included in the study. Gut microbiota were assessed from the participants’ fecal samples. The diversity and richness of microbial populations in each sample were assessed by the Chao1-estimated OTU number and the Shannon index. Results: The Chao1-estimated OTU number and Shannon index were similar between HF and control groups. There was no statistically significant relationship between inflammatory marker levels (tumor necrosis factor-alpha, interleukin 1-beta, endotoxin, C-reactive protein, galectin-3, interleukin 6, and lipopolysaccharide-binding protein) and microbial richness and diversity when analyzed at the phylum level. Conclusion: In the current study, compared to patients with CAD but without HF, stable HF patients with CAD did not show changes in gut microbial richness and diversity. At the genus level Enterococcus sp. was more commonly identified in HF patients, in addition to certain changes in species levels, including increased Lactobacillus letivazi.
AtıfScopus8OpenAlex7İncele - MakaleYalnız künye2023Scopus SJRQ1Full-scale structural evaluations of İskenderpaşa minaret
Aymelek, Abdullah; Yanik, Yusuf; Demirtaş, Betül; Yildirim, Ömer; Çalik, İsmet; Türker, Temel
Nowadays, innovative methods have been used for observing and structural evaluating of historical structures. In this paper, it is presented the full-scale structural assessments of a minaret after a Finite Element model calibrating according to vibration test results. Also, the structural behaviours under earthquake and wind loads were identified by considering the environmental effects on the selected masonry minaret of İskenderpaşa Mosque. First of all, modal analysis was executed on the three-dimensional Finite Element model created according to field survey in ANSYS Workbench. In-situ vibration tests were implemented at different intervals by using developed vibration measurement system. The experimental modal parameters were attained from collected signals. The experimental results were used as reference values in model calibration of this minaret to reflect the existing structural behaviour. Model calibration process was carried out on the initial model both by changing of material properties of masonry wall and by taking into account the interactions with mosque walls and ground. Full-scale structural evaluation was carried out under earthquake and wind loads on both the initial and the calibrated models in the weak direction of this minaret. The top displacements, drift ratios, principal stress values and their distributions were determined. It was shown that the analyses on the calibrated model produce more realistic structural behaviour.
AtıfScopus21WoS20OpenAlex22İncele - MakaleAçık Erişim2023Scopus SJRQ3A study on Li-ion battery and supercapacitor design for hybrid energy storage systems
Çorapsiz, Muhammed Reşit; Kahveci, Hakan
This paper discusses a generic design of lithium-ion (Li-ion) batteries and supercapacitors, which are important sources for energy storage systems (ESS). The main contribution of this study is to compare the available and experimental models for batteries and supercapacitors operating under continuous charge or discharge conditions. Even though the available models show similar behavior to the experimental ones in short-term or pulsed discharge conditions, this situation may be different in continuous discharge conditions. For this purpose, the optimal electrical equivalent circuits of energy storage devices were constituted and modeled in the MATLAB/Simulink environment. Then, the electrical equivalent circuit parameters were approximately calculated with the help of dynamic equations. Finally, the model parameters were estimated using Nonlinear Least Squares Method (NLSM) and Trust Region Reflective Algorithm (TRRA). When the obtained results were evaluated together, it has been observed that the electrical equivalent circuit models (EECM) more accurately reveal the transient and steady states of energy storage devices compared to the available models, especially under continuous discharge conditions.
AtıfScopus33WoS30OpenAlex33İncele - Kitap BölümüAçık Erişim2025Beyond Algorithms: Unveiling the Intersection of AI Ethics, Citizenship Education, and Social Studies
Yetişensoy, Okan
The rapid rise of artificial intelligence (AI) in recent years has led to various positive transformations in everyday life. However, this rise has also brought about the emergence of some ethical issues that raise concerns in society. Examples of these ethical issues include the manipulative or harmful use of AI, privacy concerns, bias, discrimination, and lack of transparency and accountability. AI ethics, on the other hand, represent a set of guiding principles that stakeholders should adopt to ensure the responsible development and utilization of AI technologies. Considering that young people are potential users and developers of AI, teaching them these principles from an early age can be seen as a natural part of citizenship education. Thus, incorporating AI ethics-related content into the curriculum of various K-12 courses can be regarded as an effective approach. This chapter argued that social studies, with its focus on fostering effective citizens for the future, will emerge as a crucial application area for this approach. At this point, the relevant study aims to explore the intersections between AI ethics, citizenship education, and social studies. It is believed that the study will make a significant contribution to the literature by revealing the new dynamics created by AI in citizenship education and demonstrating the potential role that the social studies curriculum can play in this regard.
AtıfScopus2WoS2OpenAlex2İncele - MakaleAçık Erişim2024Scopus SJRQ3Examining the Earthquake Awareness Levels of Teacher Candidates in Terms of Various Variables; [Öǧretmen Adaylarinin Deprem Farkindalik Düzeylerinin Çeşitli Deǧişkenler Açisindan Incelenmesi]
Degirmenci, Yavuz; Altunay, Furkan
Earthquakes are one of the most important and destructive natural disasters that frequently occur both in the world and in Türkiye, affecting living things and the environment, especially humans, in various aspects. It is a fact that despite today's technological possibilities and knowledge, the desired level has not yet been reached in preventing and predicting earthquakes. However, as with other disasters, individuals' preparedness and awareness for earthquakes is effective in reducing the damage of earthquakes. The aim of this research is to examine the earthquake awareness levels of university students in terms of various variables. The research was conducted based on a quantitative approach. "Earthquake Awareness Scale" was used as a data collection tool in the research. Jamowi statistical program was used to analyze the data. The study group of the research consists of undergraduate students studying at the faculty of education of a state university in Türkiye in the 2022-2023 academic year. According to the findings of the research; It was determined that the earthquake awareness levels of the participants were generally high, and while there was no significant difference in terms of gender and grade point average, there was a difference according to the department variable. In addition, according to the participants, it is vital to be aware of earthquakes, but they stated that university education is not sufficient to be prepared for earthquakes.
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İncele - MakaleYayıncıda açık erişim2024Scopus SJRQ1Investigation of Post-Transplant Mental Well-Being in Liver Transplant Recipients with Hepatic Encephalopathy
Saritaş, Serdar; Tarlaci, Sultan; Bulbuloglu, Semra; Guneş, Hüseyin
Objective: In this study, we aimed to examine the healing trend of hepatic encephalopathy after transplantation surgery in patients with liver failure. Method: We conducted this descriptive and cross-sectional study with the participation of liver transplant recipients. A personal information form, the West Haven Criteria (WHC), the Warwick-Edinburgh Mental Well-Being Scale (WEMWBS), and the Richmond Agitation Sedation Scale (RASS) were used for data collection. The data were analyzed using Chi-squared tests, ANOVA, and paired-samples t-tests. Results: As time progressed after liver transplantation, hepatic encephalopathy stages regressed (p < 0.01). We found that liver transplant recipients with end-stage hepatic encephalopathy were mostly within the first 6 months after transplantation, while patients with first-stage hepatic encephalopathy had received liver transplants more than 2 years ago (p < 0.01). Conclusions: The results of our study revealed that hepatic encephalopathy stages regressed after transplantation, but there was no complete recovery. This highlights the need to develop new treatment strategies other than liver transplantation for the treatment of hepatic encephalopathy.
AtıfScopus5WoS5OpenAlex6İncele - MakaleYalnız künye2023Scopus SJRQ1Genetic algorithm enabled virtual multicast tree embedding in Software-Defined Networks
Guler, Evrim; Karakus, Murat; Ayaz, Furkan
The recent network virtualization technology enables the multi-tenancy, where various virtual network requests can share the same physical network by decoupling network services from the underlying hardware architecture. The process of virtual node and link mapping onto a shared Substrate Network (SN) by satisfying the requested network resources (i.e., bandwidth, computing capacity, etc.) is referred to as Virtual Network Embedding (VNE), which is known as an NP-Hard problem. The problem of VNE aims to exhibit one-to-one (unicast) communication. However, the motivation of this research is to explore how to efficiently map virtual networks with one-to-many (multicast) communications, which are in the form of Virtual Multicast Trees (VMTs), onto an SN. This problem differs from the traditional VNE problem and has not been well-studied by the research community. To this end, we propose a novel algorithm, Modified Genetic Algorithm for Virtual Multicast Tree Embedding (MGA-VMTE), to embed VMTs onto a shared SN in this research. The proposed MGA-VMTE algorithm focuses on minimizing the network resource consumption (i.e., bandwidth) under end-to-end delay constraint in the SN while satisfying the computing request of virtual nodes. Our extensive simulations demonstrate that the MGA-VMTE algorithm outperforms the dynamic impact factor and traditional greedy-based virtual multicast tree embedding approaches regarding bandwidth consumption, acceptance ratio, and resource depletion ratio metrics on NSFNET, USNET, Random-60 node, and Random-120 node network topologies.
AtıfScopus16WoS12OpenAlex16İncele - MakaleYalnız künye2024Scopus SJRQ1Intelligent detection of airport pavement subtle crack based on one-stage anchor-free deep neural network
Yuan, Bo; Tapkın, Serkan; Pei, Lili; Tercan, Emre; Zhao, Kaiyue; Li, Wei
To solve issues with low-detection accuracy and high-missed detection rate in subtle pavement cracks, this research proposed an intelligent detection method based on a one-stage anchor-free deep neural network, which consists of a feature extraction network, detection neck, and detection head. The feature extraction network with an extended deep attention network is responsible for extracting the features and output at different scales. The detection neck containing the special spatial pyramid structure fuses the contextual information of different scales to improve the abstract features. The detection head is composed of the anchor-free mechanism with decoupling property and the reparameterized structure to improve the detection accuracy and balance the algorithm complexity. The experimental results demonstrate that the Precision, Recall, and F1-Score are, 92.74%, 91.92%, and 0.9233 respectively. It has advantages over the most advanced one-stage detection method. Based on testing results, it has prominent stability and robustness for subtle pavement crack detection.
AtıfScopus1WoS1OpenAlex2İncele - MakaleAçık Erişim2023Scopus SJRQ2The effect of guided imagery on postoperative pain and comfort of geriatric orthopaedic patients: a randomized controlled trial
Ozdemir, Ahmet; Gunes, Hüseyin; Saritas, Serdar
Background: The purpose of this study is to investigate the effects of guided imagery on postoperative pain and comfort in geriatric orthopedics patients. Methods: This study was carried out with a randomized-controlled true experimental design. The population of the study included geriatric patients receiving treatment at the orthopedics and traumatology inpatient clinic of a university hospital. Based on random selection, the sample consisted of total of 102 patients, including 40 patients in the experimental group and 40 in the control group. The data were collected using a Personal Information Form, the Visual Analog Scale, and the General Comfort Questionnaire. Results: After the guided imagery intervention, the pain levels of the experimental group significantly decreased compared to their baseline pain levels (t = 4.002, P = 0.00). Their perceived comfort was also significantly improved (t = −5.428, P = 0.00). Although the perceived comfort of the control group decreased, this decrease was not statistically significant (t = 0.698, P = 0.489). Conclusion: It is recommended that guided imagery, which is an inexpensive and accessible method, be integrated into the nursing care process to reduce the pain and increase the comfort of geriatric orthopedics patients.
AtıfScopus3WoS1OpenAlex4İncele - MakaleAçık Erişim2025Scopus SJRQ1Preschool children's social skills, problem behaviors, academic self-esteem and teacher-child relationship: a serial mediation model
Tutkun, Cansu; Eskidemir Meral, Seda
Introduction: Research has shown that children's social skills have effects on their problem behaviors. However, the mechanisms through which social skills contribute to reducing problem behaviors need further clarification. Methods: This study examined the relationship between preschool children's social skills and problem behaviors, as well as the independent and serial mediating roles of academic self-esteem and teacher-child relationship in this relationship. The study included 382 children aged 3–5 years, randomly selected in Türkiye. Results and discussion: As a result of the study: (1) there was a significant and negative relationship between problem behaviors and social skills, academic self-esteem and teacher-child relationship; (2) the mediating role of academic self-esteem and teacher-child relationship in the relationship between social skills and problem behaviors was supported; and (3) the serial mediating role of academic self-esteem and teacher-child relationship in the effect of social skills on problem behaviors, respectively, was found. These findings indicated that children's social skills may help to increase their academic self-esteem, improve the teacher-child relationship, and thus reduce their problem behaviors. Therefore, these results have important implications for designing interventions to increase preschool children's social skills, academic self-esteem, and teacher-child relationship, as well as to prevent the early development of problem behaviors.
AtıfScopus5WoS4OpenAlex5İncele - MakaleYalnız künye2023Scopus SJRQ1Electrical, Magnetic, Microstructural, and Characteristic Properties of Zirconium-Substituted Co0.5 Ni0.5 Zrx Fe2− x O4 Spinel Ferrite Nanostructures
Teber, Ahmet; Sarac, Mehmet F.
The effect of zirconium (Zr) substitution in nickel–cobalt ferrites, Co0.5Ni0.5ZrxFe2−xO4 (0.0 ≤ x ≤ 1.0) produced by the hydrothermal method on the electrical, magnetic, microstructural and characteristic properties are reported. A secondary phase as tetragonal-ZrO2 phase in the crystal system is detected and have both M-type hexagonal and tetragonal nanocrystallites between 32 and 67 nm. Refined structural parameters using Rietveld analysis are carried out, resulting in lattice parameters, the unit cell volume, parameter ratios, and the crystallite size using the TOPAS refinement program. In addition, residuals for the RBragg factor and goodness of fit (χ2) value for each concentration are represented. The Rietveld analysis determines that the predicted and actual diffraction patterns are in accord. Furthermore, the Zr effect is presented in unit volume as seen by the drop in peak intensity that occurs (with the addition of Zr) due to the lattice tension. Moreover, the morphological analyses indicate that the shape transformed from agglomerated clusters to oval-shaped structures and a reduction in grain size. Fourier transform infrared (FT-IR) analysis in the range of 4000–450 cm−1 correlates with the presence of the hexagonal spinel ferrite structure. The dielectric parameters, such as the relative permittivity, tangent loss, and ac conductivity, are experimentally measured with the oscillation voltage level of 0.05 V in the frequency range of 0.1–10 MHz. The dielectric permittivities and tangent losses of the specimens decreased with an increment in frequency. Magnetic measurements reveal that the values of coercivity (Hc) have the propensity to increase relating to the zirconium concentration.
AtıfScopus2WoS3OpenAlex4İncele - MakaleAçık Erişim2023Scopus SJRQ3Exploring Turkish parents’ lived experiences on online science lessons of their children with mild intellectual disability amid the COVID-19 pandemic
Yarımkaya, Derya; Töman, Ufuk
Background: The purpose of this qualitative study was to explore Turkish parents’ lived experiences on online science lessons of their children with mild intellectual disability amid COVID-19 pandemic. Method: This study used the phenomenological qualitative research design. Participants in this study were 16 parents, who have children with mild intellectual disability and participated in one-on-one semi-structured phone calls. Interview data were thematically analyzed. Result: Five overarching themes were found: (1) parents’ general experiences on online science lessons, (2) advantages of online science lessons, (3) disadvantages of online science lessons, (4) barriers in online science lessons, and (5) parents’ recommendations for online science lessons. Conclusion: The results revealed that the majority of parents agreed on the school closure policy due to the COVID-19 pandemic, but were not satisfied with the online science lessons, and focused on the disadvantages of online science lessons for their children with mild intellectual disability.
AtıfScopus6WoS10OpenAlex14İncele
