Koleksiyon/r/bayburt/10001

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Koleksiyondaki öğeler

  • MakaleAçık Erişim2024Scopus SJRQ1
    Synthesis of flaxseed gum/melanin-based scaffold: A novel approach for nano-encapsulation of doxorubicin with enhanced anticancer activity

    Kumar, Deepak; Pal, Ravi Raj; Das, Neeladri; Roy, Partha; Saraf, Shubhini A.; Bayram, Sinan; Kundu, Patit P.

    Doxorubicin is a powerful chemotherapy medicine that is frequently used to treat cancer, but because of its extremely destructive side effects on other healthy cells, its applications have been severely constrained. With the aim of using lower therapeutic doses of doxorubicin while maintaining the same anti-cancerous activity as those of higher doses, the present study designs nano-encapsulation of doxorubicin by acrylamide grafted melanin as core and acrylic acid grafted flax seed gum as shell (DOX@AAM-g-ML/AA-g-FSG-NPs) for studies in-vivo and in-vitro anticancer activity. For biological studies, the cytotoxicity of DOX@AAM-g-ML/AA-g-FSG-NPs was examined on a cancerous human cell line (HCT-15) and it was observed that DOX@AAM-g-ML/AA-g-FSG-NPs exhibited very high toxicity towards HCT-15. In-vivo investigation in colon cancer-inflicted rat model also showed that DOX@AAM-g-ML/AA-g-FSG-NPs showed better anticancer activity against cancerous cells as compared to free doxorubicin. The drug release behavior of DOX@GML-GFS-NPs was studied at several pH and maximum drug release (95 %) was recorded at pH -7.2, and kinetic data of drug release was follows the Higuchi (R2 = 0.9706) kinetic model. Our study is focussed on reducing the side effects of doxorubicin by its nano-encapsulation in acrylamide grafted melanin as core and acrylic acid grafted flax seed gum that will also enhance its efficiency.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus14WoS14OpenAlex15
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2024Scopus SJRQ1
    Phytochemical profile, enzyme inhibition, antioxidant, and antibacterial activity of Rosa pimpinellifolia L.: A comprehensive study to investigate the bioactivity of different parts (whole fruit, pulp, and seed part) of the fruit

    Findik, Bahar Tuba; Yildiz, Hilal; Akdeniz, Mehmet; Yener, Ismail; Yilmaz, Mustafa Abdullah; Cakir, Ozlem; Ertas, Abdulselam

    The pharmaceutical and nutraceutical potentials of whole fruit, pulp and seeds of Rosa pimpinellifolia L. were evaluated. Forty-two phenolic compounds and two triterpenoids were identified in extracts by LC-MS/MS and GC–MS, respectively. The most prominent compounds were ellagic acid, catechin, epicatechin, tannic acid, quercetin, oleanolic acid, and ursolic acid. The highest enzyme inhibitory activities of the extracts (94.83%) were obtained against angiotensin-converting enzyme and were almost equal to those of the commercial standard (lisinopril, 98.99%). Whole fruit and pulp extracts (IC50:2.47 and 1.52 μg DW/mL) exhibited higher antioxidant capacity than the standards (α-tocopherol, IC50:9.89 μg DW/mL). The highest antibacterial activity was obtained against Bacillus cereus (MIC: 256 μg/mL) for the whole fruit extract. Correlation analyses were conducted to find the correlation between individual phenolics and enzyme inhibitory activities. The results showed the remarkable future of not only the edible part but also the seeds of black rose hips in phytochemical and functional aspects.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus15WoS14OpenAlex17
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2022Scopus SJRQ1
    Powder flow behaviour, functional characteristics and microstructure of whole milk powder produced from cow and buffalo milk mixtures

    Sert, Durmuş; Mercan, Emin; Kılınç, Mehmet

    The effects of cow and buffalo milk mixtures on powder flow behaviour, functional characteristics and microstructure of whole milk powder was investigated. Milk powder was produced from 100% cow milk (G1), 100% buffalo milk (G2), 75% cow/25% buffalo milk (G3), 50% cow/50% buffalo milk (G4) and 25% cow/75% buffalo milk (G5). A higher proportion of buffalo milk increased the hydroxymethylfurfural, thiobarbituric acid reactive substances and free fatty acid contents in powders, but decreased dispersibility and wettability. The lowest and highest mean particle size values were obtained in G3 and G2 samples. Milk powder containing a higher level of buffalo milk increased caking ability and compaction coefficients of milk powder. All samples had remarkably cohesive characteristics. A higher proportion of cow milk can improve the flow behaviour of milk powder containing cow and buffalo milk mixtures in terms of caking, cohesion, and powder speed flow dependency.

    • SDG 2 · Açlığa Son
    AtıfScopus11WoS7OpenAlex8
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2023
    Exergetic Analyses of Hypersonic Flows

    Topal, Esra Nur; Karaali, Rabi

    Hypersonic devices and vehicles and hypersonic flows are very important and competitive advanced technology in science and in the World. Hypersonic technology is rapidly spreading and turning into competition in developed countries, especially in space studies and defense industry. This technology is vital for developed countries. Because of shock waves emerging in hypersonic devices during hypersonic flow, the energy and exergy destructions they cause are the most important difficulties, obstacles and problems which arise in this vital technology. To overcome these problems and difficulties, to prevent or reduce or minimize energy and exergy destruction, aerodynamic analysis and energy and exergy analysis methods are applied. The data and the results that can be guiding and useful for the calculations and the design have been obtained. In this study optimal design and optimum calculations ways of the energy and exergy destructions of hypersonic devices and instruments are discussed. It is obtained and shown that how much exergy destruction and entropy production occurs at which altitude and hypersonic velocities and also at which oblique shock angles.

    AtıfScopus2
    ScopusTR Dizinİncele
  • MakaleAçık Erişim2023Scopus SJRQ2
    The Effect of Different Drying Methods on Bioactive and Nutrition Contents of Bee Bread and Mathematical Modeling of Drying Characteristics

    Kutlu, Naciye; Gercek, Yusuf Can; Bayram, Nesrin Ecem

    In this study, the aim was to determine the effect of different drying methods (with microwave and hot air) on the color, nutrient and bioactive contents of fresh bee bread. Drying characteristics were also investigated. Microwave and hot air drying were applied at different microwave powers and temperatures, respectively. Lower moisture ratios and highest effective diffusion coefficients were obtained with microwave drying in a shorter time. The Midilli model was found to be the most suitable thin-layer drying model for both methods. Regardless of the drying conditions, moisture, ash, protein, carbohydrate, and lipid proportions were observed to vary in the ranges of 4.9–8.2 %, 1.61–2.67 %, 17.47–32.54 %, 39.92–60.84 %, and 7.10–8.89 %, respectively. The lowest color difference was obtained for the sample dried at 210 W. As a result, it was determined that microwave drying is more suitable for preserving the nutritional and bioactive content of bee bread during drying.

    • SDG 2 · Açlığa Son
    AtıfScopus5WoS3OpenAlex6
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2023Scopus SJRQ3
    Investigation of Use of Linden (Tilia tomentosa Moench.) Wood with UV System Varnish Application IN INDOOR Parquet Flooring

    Ayata, Ümit; Esteves, Bruno; Domingos, Idalina; Ferreira, José; Tuncay Efe, Fatih; Türk, Mutlu; Çakicier, Nevzat; Gürleyen, Levent; Peker, Hüseyin

    Linden wood is used in the making of musical instruments, agricultural hand tools, and in the furniture sector. In this study, the changes in glossiness (parallel (//) and perpendicular (⊥) to the fibers at 20°, 60°, and 85°, the pull-off adhesion test, color parameters (CIEL) and pendulum hardness (König method) of two different UV curable varnishes applied to linden (Tilia tomentosa Moench.) according to industrial application techniques and exposed to artificial weathering were investigated. According to the research results, while L*, ΔH*, and h° decreased with increasing weathering time in both varnish layers, ΔC*, b*, ΔE*, a*, and C* rose. The pendulum hardness grew for Method B but dwindled for Method A. A decrease was found in the adhesion tests for both varnish methods after artificial weathering. The glossiness was generally reduced due to artificial weathering for all the angles and for both directions, with the exception of 85º in Method A. The variance analysis and homogeneity groups showed that the changes in the adhesion, pendulum hardness, L*, a*, h°, C*, perpendicular and parallel to the fibers for 60° and 85° were found to be significantly different with artificial weathering for both methods.

    AtıfScopus1WoS1OpenAlex1
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  • MakaleAçık Erişim2023Scopus SJRQ1
    Attitudes pregnant women in Türkiye towards holistic complementary and alternative medicine and influencing factors: a web-based cross-sectional study

    Küçükkaya, Burcu; Işık, Hafsa Kübra

    Background: Pregnant women turn to holistic complementary and alternative medicine to cope with problems associated with the changes they experience during pregnancy. This study aimed to determine the attitudes of pregnant women in Türkiye toward holistic complementary and alternative medicine and influencing factors. Methods: This cross-sectional exploratory study was carried out between June and November 2022 with a web-based questionnaire distributed via social media and communication platforms. Two hundred and twenty-one pregnant women participated in the study. A "Participant Identification Form" and the "Attitudes towards Holistic Complementary and Alternative Medicine Questionnaire" were used to collect the data. Logistic regression analysis was used to determine correlations between variables and scale scores. Results: It was determined that 84.2% of the participants had knowledge about traditional and complementary therapies, and 77.8% used traditional and complementary therapies. The participants reported that they preferred faith (77.4%), energy healing (76.9%), massage (75.6%), diet (74.2%), meditation/yoga (62.0%), and herbal (59.7%) traditional and complementary therapies the most, and most of them used these methods to reduce nausea, vomiting, edema, and fatigue during pregnancy. The mean Attitudes towards Holistic Complementary and Alternative Medicine Questionnaire score of the participants was 35.0 (5.04). It was seen that having high school or higher education (p < 0.05), having an income more than expenses (p < 0.001), having received advice from nurses when having a complaint (p < 0.001), having knowledge about traditional and complementary therapies (p < 0.001), and being a practitioner who received services of traditional and complementary therapies (p < 0.001) were positively associated with the utilization of traditional and complementary therapies. Conclusion: In this study, it was determined that the attitudes of pregnant women towards holistic complementary and alternative medicine were high. Their personal characteristics, as well as their knowledge and practice of holistic complementary and alternative medicine affected their attitudes towards holistic complementary and alternative medicine. Obstetrics nurses/midwives should actively participate in training programs on traditional and complementary therapies focused on pregnant women.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus10WoS5OpenAlex9
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2024Scopus SJRQ1
    Removal kinetics of vinyl acetate under aerobic and anoxic conditions in a batch bioreactor

    Yalçın Çelik, Beste; Nuhoğlu, Alper; Kul, Sinan; İrdemez, Şahset

    Vinyl acetate is a volatile organic compound widely used in the chemical industry, and there is a need for effective and economic removal of this volatile organic compound from wastewater and waste gases in chemical industries. This study aims to determine the biological treatability of vinyl acetate both under aerobic and anoxic conditions using mixed cultures obtained from a wastewater treatment plant. Considering the previous studies in the literature, testing the biodegradability of vinyl acetate under both aerobic and anoxic conditions, together with evaluating the effect of other mechanisms, such as adsorption and volatilization, on the removal of vinyl acetate, can be regarded as the prominent part of this study. Wastewater containing artificially prepared vinyl acetate was treated in a batch bioreactor, and performance and kinetic constants were investigated. Aerobic treatment under batch conditions conformed to the Haldane biokinetic equation, and the biokinetic constants of μmax, Ks, and Ki were calculated as 0.66 h−1, 19.67 mg L−1 and 50.56 mg L−1, respectively. Anoxic treatment under batch conditions conformed to the Monod biokinetic equation, and the biokinetic constants of μmax and Ks were calculated as 0.31 h−1 and 33.88 mg L−1, respectively. Experiments revealed that vinyl acetate was not volatile, and its adsorption and biological treatment performances were 28% and 72%, respectively. The mixed culture had a very high performance for removing vinyl acetate under batch operating conditions. The primary mechanism of vinyl acetate removal was found to be biological treatment.

    • SDG 6 · Temiz Su ve Sanitasyon
    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfOpenAlex1
    ScopusWeb of SciencePubMedİncele
  • MakaleYalnız künye2023Scopus SJRQ3
    Comparison of the critical power estimated by the best fit method and the maximal lactate steady state; [Comparaison entre la puissance critique estimée par la méthode bien-être et l’état d’équilibre maximal du lactate]

    As, H.; Cabuk, R.; Norouzi, M.; Balci, G.A.; Ozkaya, O.

    Aims: Maximal lactate steady state (MLSS) is accepted as the gold standard method to determine the upper boundary of heavy exercise domain, while critical power (CP) is one of the most practical ways to estimate the lower boundary of severe exercise domain. However, it has been recently discussed that the upper boundary of heavy-intensity exercise domain does not equal to lower boundary of severe-intensity exercise domain. Conversely, the best individual fit method (CPfit) has recently been suggested as an accurate estimation of CP. However, there has not been a comparative evaluation of CPfit versus MLSS. The aim of this study was, therefore, to focus on the comparison of CPfit with MLSS. Methods: Eleven well-trained male cyclists participated in this study. Following the determination of maximal oxygen uptake, MLSS was determined through the performance of standard 30-minute constant work rate exercises performed on separate days. Cyclists performed four constant-load exercises lasting 2–15 minutes on different days. The data were then fitted to mathematical models to obtain CPfit. Bland-Altman plot with 95% limits of agreement (LoA) was used to measure agreement between CPfit and MLSS. Results: According to the findings, CPfit overestimated the work rate corresponding to MLSS (300 ± 38 W vs. 265 ± 39 W; P = 0.001; effect size = 3.28). Bland-Altman results showed high LoA (14 to 55.9 W) and very high bias (bias = 35 ± 10.7 W; P = 0.001; r: 0.96) between CPfit and MLSS. Conclusion: CPfit was not identical for MLSS.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus1WoS2OpenAlex3
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2024Scopus SJRQ2
    A Dual-Band Terahertz Metamaterial Absorber Using an All-Metal Aluminum Hexagonal Metasurface Structure for Sensing of Cancerous Cells

    Teber, Ahmet

    This article proposes a dual-band terahertz metamaterial absorber (TMA) where all components of the designed structure are made of aluminum (optical) material. Unlike the metal-dielectric-metal structures typically found in the literature, the proposed structure has a lightweight material that does not contain a sandwich structure. Thus, the structure greatly simplifies the production process and reduces the cost. The results of electromagnetic and equivalent circuit simulations are compared based on the S11 parameters (in dB), resulting in good agreement of findings by CST and ADS, respectively. The proposed TMA operates in dual frequency bands at 1.902 THz (f1) and 1.976 THz (f2), with strong absorption of 98.17% and 99.05%, respectively. The quality factors (Q-factors) corresponding to these resonant frequencies are 240.15, (f1) and 181.61, (f2). When the refractive index (RI) of the medium surrounding the TMA varies, the absorption peaks shift accordingly. The detection properties of the proposed TMA are examined as the RI of the surrounding medium is varied primarily between 1.34 and 1.39 with an increase of 0.01 for biomedical applications. The corresponding sensitivities of two resonance peaks are 0.794 THz/RIU and 0.971 THz/RIU, respectively. Since many samples, such as human blood, basal/breast/cervical cells, and cancerous cells, are found in this RI range, the proposed TMA sensor can be used as a viable biosensor in the identification of biological samples for real-world applications. Graphical Abstract: (Figure presented.)

    AtıfScopus36WoS31OpenAlex37
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  • MakaleYalnız künye2023Scopus SJRQ1
    Comparison of bioactive constituents by HPLC–DAD–ESI-MS and UFLC and in vitro antioxidant activities of blossom honey, bee pollen, and propolis

    Saroğlu, Öznur; Ecem Bayram, Nesrin; Özçelik, Beraat

    The aim of this study was to analyze the total phenolic content, phenolic profile, and antioxidant activity of honey, bee pollen, and propolis samples from Turkey's Black Sea Region. The total phenolic content of these bee products was found using Folin–Ciocalteu's method, and their antioxidant capacity was found using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and cupric ion reducing antioxidant capacity (CUPRAC) assays. Phenolic compounds of honey samples were characterized by high-performance liquid chromatography coupled to a photodiode array detector and mass spectrometer (HPLC–DAD–ESI-MS), while phenolic compounds of bee pollen and propolis samples were quantified ultra-fast liquid chromatography (UFLC). The total phenolic values for honey, bee pollen and propolis were 6.32–18.21 mg GAE/100 g, 547.64–769.4 mg GAE/100 gr, and 6096.1–11,564 mg GAE/100 gr, respectively. DPPH and CUPRAC values of honey, pollen and propolis were 11.05–21.38% and 0.38–1.48 µmol Trolox/g; 24.67–38.63% and 0.03–0.05 mmol Trolox/g; 11.81–34.12% and 0.47–0.89 mmol Trolox/g, respectively. About 30 different phenolic compounds were identified as quantitative. Our findings have shown that all bee products examined in the study are found to contain gallic acid, naringenin, and caffeic acid. In terms of total phenolic content and antioxidant activity, the bee product extracts were ranked as follows: propolis > bee pollen > honey. The high concentration of phenolic compounds in propolis explains its remarkable antioxidant effect.

    AtıfScopus10WoS10OpenAlex10
    ScopusWeb of Scienceİncele
  • Kitap BölümüYalnız künye2023
    Metasurfaces

    Kaya, Yunus

    The purpose of this book chapter is to ensure an extensive and appropriate definition of MSs, to determine their outstanding features, and also to emphasize some of the advantages that may be gained by using them. A superior property of MSs is their low loss behavior in contrast to MMs. Therefore, MSs permit us to use the extraordinary properties of MMs such as refraction and reflection without incurring production complications and the losses related to MMs.

  • MakaleAçık Erişim2024Scopus SJRQ4
    Di-Darboux Slant Helices on Surface

    Alkan, Akın; Kocayiğit, Hüseyin; Ağırman Aydın, Tuba

    In this study, we consider Di-Darboux slant helices which are new surface curves on an oriented surface. We give some characterizations for such curves according to the Darboux frame, OD-frame, ND-frame, RD-frame, and obtain axes of the Di-Darboux slant helices. Moreover, the position vectors of the Di-Darboux slant helices are obtained.

    AtıfOpenAlex2
    ScopusTR Dizinİncele
  • MakaleYalnız künye2022Scopus SJRQ3
    Optimization of Ultrasound Extraction of Phenolic Compounds from Tarragon (Artemisia dracunculus L.) Using Box–Behnken Design

    Kutlu, Naciye; Kamiloglu, Aybike; Elbir, Tugba

    In this study, ultrasound extraction of bioactive compounds from tarragon was examined as a sustainable technology. Pure water, which is a green solvent, was used as solvent. Box–Behnken was used in the experimental design, and ultrasonic power, extraction time and solvent-to-sample ratio were determined to be independent variables. The physicochemical properties were determined by physical (color, pH, Brix) and chemical analyses (antioxidant activity, total flavonoid and total phenolic compound (TPC)) in the extracts obtained under different conditions. Optimum conditions were found to be 73.9% ultrasonic power, 43.2 min sonication time and 10 mL/g solvent-to-sample ratio. The composite desirability (R2) of optimum conditions was 99.3% after optimization. Since high efficiency was obtained in a short time with ultrasound extraction, it was found to be quite good in terms of energy savings. That is, the highest TPC was obtained with a sonication time of 45 min with this method, while similar TPC in the control group (maceration) was obtained in 24 h. In the optimum conditions, extraction with other green solvents (ethanol and deep eutectic solvent—DES) was carried out and bioactive compound yields were compared. For different solvents compared under optimum conditions, ethanol gave higher yields in terms of TPC, while higher yields were obtained in samples using water as solvent for some antioxidant activity values. The results obtained with DES were not as high as expected, and this resulted in the conclusion that a hydrogen bond donor is not suitable for obtaining bioactive compounds from tarragon.

    • SDG 12 · Sorumlu Üretim ve Tüketim
    AtıfScopus9WoS9OpenAlex9
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2024Scopus SJRQ2
    A new face presentation attack detection method based on face-weighted multi-color multi-level texture features

    Turhal, Uğur; Günay Yılmaz, Asuman; Nabiyev, Vasif

    Biometric data (facial, voice, fingerprint, and retinal scans, for example) are widely used in identification due to their unique and irreversible nature. Facial recognition technologies are employed in a wide range of applications due to their contactless nature and convenience. However, technological advancements and the availability of access to personal information have rendered these biometric systems susceptible to attacks utilizing fake faces. As a result, the issue of anti-spoofing has emerged as a critical one in the field of facial recognition. This study proposes a joint face presentation attack (FPA) detection method based on face-weighted multi-color multi-level LBP features extracted from the combination of device-dependent HSV and device-independent L*a*b* color spaces. The facial images were converted to HSV and L*a*b* color spaces. Three levels of regional LBP features were extracted from each color channel and then concatenated. Finally, a Multi-Color Multi-Level LBP (MCML_LBP) feature vector was obtained. In addition, the Face Weighted MCML_LBP feature vector was produced (FW_MCML_LBP) by adding the LBP histogram extracted from the central region of the normalized image. The feature vectors are used to train an SVM classifier after reducing their size using PCA. Twenty-five different test scenarios were subjected to experimentation on the CASIA and Replay-Attack databases. 2.11% EER and 0.19% HTER were achieved on CASIA (Overall) and Replay-Attack (Grandtest) databases, respectively, using the L*a*b color space and the proposed feature extraction method. The results of the study showed that the proposed method was successful in FPA detection compared to the state-of-the-art methods.

    AtıfScopus11WoS10OpenAlex10
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2024Scopus SJRQ2
    Interleukin-27 as a novel player in alleviating hepatic steatosis: Mechanistic insights from an in vitro analysis

    Cho, Wonjun; Oh, Heeseung; Abd El-Aty, A.M.; Özten, Ömer; Jeong, Ji Hoon; Jung, Tae Woo

    Interleukin-27 (IL-27) is a recently discovered cytokine that has been implicated in inflammatory and metabolic conditions, such as atherosclerosis and insulin resistance. However, the mechanisms by which IL-27 attenuates hepatic lipid accumulation in hyperlipidemic conditions and counteracts endoplasmic reticulum (ER) stress, a known risk factor for impaired hepatic lipid metabolism, have not been elucidated. This in vitro study was designed to examine the effect of IL-27 on hepatic lipid metabolism. The study included the evaluation of lipogenesis-associated proteins and ER stress markers by Western blotting, the determination of hepatic lipid accumulation by Oil Red O staining, and the examination of autophagosome formation by MDC staining. The results showed that IL-27 treatment reduced lipogenic lipid deposition and the expression of ER stress markers in cultured hepatocytes exposed to palmitate. Moreover, treatment with IL-27 suppressed CD36 expression and enhanced fatty acid oxidation in palmitate-treated hepatocytes. The effects of IL-27 on hyperlipidemic hepatocytes were attenuated when adenosine monophosphate-activated protein kinase (AMPK) or 3-methyladenine (3 MA) were inhibited by small interfering RNA (siRNA). These results suggest that IL-27 attenuates hepatic ER stress and fatty acid uptake and stimulates fatty acid oxidation via AMPK/autophagy signaling, thereby alleviating hepatic steatosis. In conclusion, this study identified IL-27 as a promising therapeutic target for nonalcoholic fatty liver disease (NAFLD).

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus6WoS6OpenAlex6
    ScopusWeb of SciencePubMedİncele
  • MakaleAçık Erişim2022Scopus SJRQ1
    Optimum sizing design of steel frame structures through maximum energy dissipation of friction dampers under seismic excitations

    Artar, Musa; Carbas, Serdar

    This paper focuses on optimum sizing design of steel frame structures equipped with friction dampers (FDs) in order to prevent the vulnerable effect of an earthquake. The fundamental concept is to maximize the energy dissipation of implemented FDs under different seismic excitations. The FDs utilized as passive energy dissipation devices in a steel structure increase the energy dissipation capacity of the structure by decreasing the seismic demand during an earthquake. In this context, the Pall friction dampers (PFDs) are implemented as diagonal damped brace members in investigated structures. Three different earthquake records (Kobe, Kocaeli-Duzce, Erzincan) are utilized to acquire nonlinear dynamic responses of the steel frame structures through time-history analyses. The open application programming interface (OAPI) functions are used to integrate a finite element modelling based structural analysis program, SAP2000, with a design optimization algorithm encoded in MATLAB for achieving the exact structural behaviours by synchronously data transferring. As an optimizer, one of the recent nature-inspired metaheuristic techniques, so-called Grey Wolf (GW) algorithm is used. Initially, under effect of seismic excitations, the steel frame structures are optimally sized for attaining minimum design weights without implementing the PFD elements by subjecting only strength, displacement, drift, and geometric structural design constraints taken from AISC-LRFD practice code provisions. Afterward, in order for optimally modelling the PFD elements, the frames are equipped with PFDs to calculate optimum yield strengths that is defined as slip load of a PFD. To do so, the GW algorithm ensures the maximizing of the dissipated energy and controls the yield strengths between the stories since the shear force due to the earthquake increases towards the base of the structure. Eventually, the provisions-based sizing design optimizations of the steel frame structures equipped with optimally modelled PFD elements are conducted under seismic excitations for conclusive evaluations.

    • SDG 9 · Sanayi, Yenilikçilik ve Altyapı
    AtıfScopus21WoS18OpenAlex20
    ScopusWeb of Scienceİncele
  • MakaleYayıncıda açık erişim2025Scopus SJRQ2
    Primula longipes subsp. bayburtensis Sefali, Yapar & Demir (Primulaceae): A new taxon from north-eastern Anatolia, Türkiye

    Sefalı, Abdurrahman; Yapar, Yakup; Demir, İbrahim; Yurtvermez, Bayram; Keser, Ali Murat

    The new taxon, Primula longipes subsp. bayburtensis Sefali, Yapar & Demir, subsp. nov. (Primulaceae) is described and illustrated from Bayburt Province, Türkiye. It is morphologically assigned to Primula sect. Crystallophlomis based on its long scapes, lanceolate and denticulate leaf with long petiole and hairless habit, fruits longer than calyx and covered by farina on the scape. This new taxon is similar to Primula longipes and P. nivalis subsp. turkestanica; it can also be easily distinguished by its calyx divided ratio, thurm flowers (unwidened corolla tube shape and length) and capsules (length) futures.

  • MakaleAçık Erişim2023Scopus SJRQ1
    Investigation of student experiences with ChatGPT-supported online learning applications in higher education

    Kayalı, Bünyami; Yavuz, Mehmet; Balat, Şener; Çalışan, Mücahit

    The purpose of this study was to determine university students' experiences with the use of ChatGPT in online courses. The sample consisted of 84 associate degree students from a state university in Turkey. A multi-method approach was used in the study. Although quantitative data were collected using the Chatbot Usability Scale, qualitative data were collected using a semi-structured interview form that we developed. The data were analysed using descriptive and content analysis methods. According to the findings, ChatGPT exhibits advantages such as a user-friendly interface and fast, concise, relevant responses. Moreover, emphasizing its contribution to the learning process, the information provided was sufficient and topic-oriented. The understandability of the chatbot’s functions and the clarity of their communication were emphasized. However, there are disadvantages such as performance issues, frequency of errors and the risk of providing misleading information. Concerns have also been raised about the potential difficulties chatbots may face in ambiguous conversations and providing insufficient information on privacy issues. In conclusion, ChatGPT is recognised as a potentially valuable tool in education based on positive usability impressions; however, more research is needed for its safe use. Implications for practice or policy • Based on positive usability impressions, students and instructors can use ChatGPT to support educational activities. • ChatGPT can promote and enhance students' personalised learning experiences. • ChatGPT can be used in all higher education courses. • Users should be cautious about the accuracy and reliability of the answers provided by ChatGPT. • Decision-makers should take precautions against risks such as privacy, ethics, confidentiality and security that may arise from using artificial intelligence in education.

    • SDG 4 · Nitelikli Eğitim
    AtıfScopus79WoS48OpenAlex76
    ScopusWeb of Scienceİncele
  • MakaleYalnız künye2024Scopus SJRQ1
    Objective Parameters in Attention Deficit Hyperactivity Disorder: Eye and Head Movements

    Yıldırım Demirdöğen, Esen; Akıncı, Mehmet Akif; Bozkurt, Abdullah; Turan, Bahadır; Esin, İbrahim Selçuk; Donbaloğlu, Mehmet Ali; Bingöl, İsa; Tümüklü Özyer, Gülşah; Kılıç, Uğur; Dursun, Onur Burak

    Objective: We aimed to evaluate eye and head movements, which are objective parameters in ADHD. Method: While the children were watching the course video task, which included the relevant (teacher and smart board) and irrelevant (any regions outside the relevant area) areas of interest, their eye movements were evaluated through eye tracking, and video recordings were made simultaneous. Head position estimation was made using through video recordings. The proportion of total fixation duration on areas of interest (PFDAOI) and saccade count, amplitude, velocity for eye movements, number of total head movements and angular change of head movement in x-y-z axes for head movements were compared. Results: Children with ADHD had lower PFDAOI on the relevant area, and had more saccade and head movements The angular change of head movement in the x-axis was higher in the ADHD group. Conclusion: In the assessment of ADHD, the eye and head movements may be particulary useful.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus4WoS4OpenAlex4
    ScopusWeb of SciencePubMedİncele