Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(116)
- Şahin, Engin(48)
- Kaya, Yunus(46)
- Özen, Soner(46)
- İspirli, Hümeyra(45)
- Pat, Suat(44)
- Şenay, Volkan(42)
- Korkmaz, Şadan(36)
- Yilmaz, Mustafa Tahsin(33)
- Kutlu, Naciye(32)
- Cuce, Erdem(31)
- Öner, Erdal(31)
- Artar, Musa(30)
- Ertugrul, Mehmet(29)
- Hasar, Ugur Cem(29)
- Mercan, Emin(28)
- Bayraktar, Bülent(27)
- Bayram, Sinan(27)
- Can, Zehra(25)
- Ecem Bayram, Nesrin(25)
- Çolak, Murat(23)
- Özdemir, Akın(23)
- Cuce, Pinar Mert(22)
- Sert, Durmuş(22)
- Ayata, Ümit(21)
- Bayram, Ozkan(21)
- Dirican, Ebubekir(20)
- Abdioglu, Murat(19)
- Ayazoglu, Rabil(19)
- Birinci, Ahmet(19)
- Kamiloğlu, Aybike(19)
- Gerçek, Yusuf Can(18)
- Taylan, Osman(18)
- Tozlu, Alperen(18)
- Gul, Volkan(15)
- Hasar, Ugur C.(15)
- Kadakal, Mahir(15)
- Sagdic, Osman(15)
- Ergün, Mustafa(14)
- Kadakal, Huriye(14)
Yayınlar
- MakaleAçık Erişim2022Scopus SJRQ3Production of enantiomerically enriched chiral carbinols using whole-cell biocatalyst
Baydaş, Yasemin; Kalay, Erbay; Şahin, Engin
Biocatalytic asymmetric reduction of ketone is an efficient method for the production of chiral carbinols. The study indicates selective bioreduction of different ketones (1–8) to their respective (R)-alcohols (1a–8a) in low to high selectivity (0- >99%) with good yields (11–96%). In this work, whole-cell of Lactobacillus kefiri P2 catalysed enantioselective reduction of various prochiral ketones was investigated. (R)-4-Phenyl-2-butanol 2a, which is used as a precursor to antihypertensive agents and spasmolytics (anti-epileptic agents), was obtained using L kefiri P2 in 99% conversion and 91% enantiomeric excess (ee). Moreover, bioreduction of 2-methyl-1-phenylpropan-1-one substrate 8, containing a branched alkyl chain and difficult to asymmetric reduction with chemical catalysts as an enantioselective, to (R)-2-methyl-1-phenylpropan-1-ol (8a) in enantiomerically pure form was carried out in excellent yield (96%). The gram-scale production was carried out, and 9.70 g of (R)-2-methyl-1-phenylpropan-1-ol (8a) in enantiomerically pure form was obtained in 96% yield. Also especially, the yield and gram scale of (R)-2-methyl-1-phenylpropan-1-ol (8a) synthesised through catalytic asymmetric reduction using the biocatalyst was the highest report so far. The efficiency of L kefiri P2 for the conversion of the substrates and ee of products were markedly influenced by the steric factors of the substrates. This is a cheap, clean and eco-friendly process for production of chiral carbinols compared to chemical processes.
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İncele - MakaleAçık Erişim2022Scopus SJRQ3Contributions on the southern distribution of Vespertilio murinus Linnaeus, 1758 (Chiroptera: Vespertilionidae) from Türkiye
Karataş, Ahmet; Bulut, Şafak; Sefali, Abdurrahman; Toprak, Ferhat; Şahin, Mehmet Kürşat; Özkurt, Şakir Önder
Vespertilio murinus Linnaeus, 1758, has a wide distribution from France to Japan, and from Iran in the south to Scandinavia and Russia in the north. The only records of the parti-coloured bat, Vespertilio murinus known from Turkey so far were based on subfossils, remains from owl pellets, and ultrasound recordings. We present the first records of live individuals from two Turkish provinces, Ardahan and Bayburt. Additionally, based on echolocation call records, its known distribution in the Anatolian Peninsula was proved to be wider. The global distribution of the species has been mapped by using ecological niche modelling. The results revealed that its distribution is highly influenced by precipitation dynamics. Although no cases of domestic cat predation on bats have previously been documented in Turkey, this paper also provides the first case study of V. murinus predated by a domestic cat in Ardahan, in November 2003.
AtıfScopus3WoS2OpenAlex2TR Dizin2
İncele - MakaleYalnız künye2022Scopus SJRQ1Bioactive and technological properties of an α-D-glucan synthesized by Weissella cibaria PDER21
Yilmaz, Mustafa Tahsin; Ispirli, Humeyra; Taylan, Osman; Alamoudi, Mohammed; Dertli, Enes
A slimy-mucinous-type colony of EPS-producing Weissella cibaria PDER21 was isolated and identified. The monomer composition was glucose, showing that the EPS is a glucan type homopolysaccharide, The core structure of (1 → 6)-linked α-D-glucose units including (1 → 3)-linked α-D-glucose branches at a ratio of 93.4/6.6 was revealed by 1H and 13C NMR spectra and confirmed by FTIR analysis. The glucan showed a superior thermal stability with almost no degradation in structure up to 300 °C. XRD analysis revealed the amorphous structure while SEM analysis confirmed the layer-like morphology. The glucan had an antioxidant activity (89.5%), water-holding capacity (103.7%) and water solubility index (80.7%) values, suggesting that the glucan had a strong level of antioxidant properties; good water binding capacity and excellent solubility. The glucan PDER21 is a polysaccharide possessing a good combination of technical and functional attributes, suggesting a great deal of potential for use in the food industry.
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İncele - MakaleYayıncıda açık erişim2022Scopus SJRQ4Investigation of CYP2E1 and Caspase-3 Gene Expressions in COVID-19 patients
Karabulut Uzuncakmak, S.; Dirican, E.; Naldan, M.E.; Kesmez Can, F.; Halıcı, Z.
Background: COVID-19 pandemic spread around the world like an infectious disease that presents waved effects on patients. Some patients needed ICU and respiratory support. Some patients only had flu-like symptoms. Cytokine storm and elevated ROS were serious problems for treatment. Apoptotic genes and CYP Family are part of these mechanisms. Aim: In this study, our aim was to examine the gene expression CYP2E1 and Caspase-3 in patients with COVID-19 infection. Method: 60 COVID-19(+) patients (ICU and non-ICU patients) and 30 healthy volunteers were enrolled to study. To measure the level of gene expression qPCR was used. The 2-ΔΔCt method was utilized to analyze gene expression. Results: The expression of CYP2E1 and Caspase-3 genes showed a significant discrepancy between patients and healthy individuals. Caspase-3 expression increased (p=0,0041) but CYP2E1 expression decreased (p=0,0214) in COVID-19 patients compared to healthy individuals. Both levels of gene expression were lower in patients with affected lungs than patients with unaffected lungs (p<0,05). Laboratory findings including d-Dimer, LDH, platelet count, lymphocyte count were related to both gene expressions (p<0,05). We found no correlation between CYP2E1 and Caspase-3 expressions. Conclusion: The expression of Caspase-3 demonstrated apoptotic situations of patients but was not related to the CYP2E1 expression level. CYP2E1 gene expression is an important actor to metabolize endogens and xenobiotics however, COVID-19 patients demonstrated decreased CYP2E1 expression. CYP2E1 and Caspase-3 gene expression levels may be used as a diagnostic tool for COVID-19 patients.
AtıfScopus8WoS5OpenAlex7İncele - MakaleAçık Erişim2022Scopus SJRQ2Inclusive Pedagogical Content Knowledge of Mathematics Teachers: Learning Disabilities vs. Hearing Impairments
Güven, Dilsad; Gürefe, Nejla; Arıkan, Ahmet
This study aims at investigating inclusive pedagogical content knowledge (IPCK) of mathematics teachers who teaches in inclusive classes including learning disabilities (LD) students or hearing impairments (HI) students in the context of angle concept. The study is a cross-case study which facilitates the comparison as one of the multiple case designs. The participants of the study are six Turkish mathematics teachers, three of them have experience of teaching to students with LD, and three of them students with HI. The data of the study is collected via semi-structured clinical interviews, and analysed using cross-case analysis. According to the findings of the study that examines the IPCK of teachers regarding the concept of angle, it can be said that teachers’ definitions of angle and their teaching strategies are insufficient. Additionally, it was found that HI teachers used much more multiple presentation such as speaking, writing, drawing shapes, and gestures than LD teachers.
AtıfScopus4WoS1OpenAlex3İncele - MakaleAçık Erişim2022Scopus SJRQ1Comparison of theoretical frameworks of doctoral theses on the field of instructional technology: The Turkey-US case
Şimşek, Eda Saka; Atila, Gülşah; Aydın, Abdulkerim; Reisoğlu, İlknur; Göktaş, Yüksel
Although there are suggestions for writing the theoretical framework in the literature, studies on how all sections of research should be structured based on the theoretical framework are limited. The current research compared the structuring of doctoral theses' theoretical frameworks in the field of instructional technology produced in Turkey and the US. Two hundred doctoral theses were subjected to content analysis based on the list of criteria developed by the researchers. The data collection tool includes the criteria of formality, language, definition and association, purpose and significance, methodological procedures, and presentation and interpretation of results. Independent factorial ANOVA were used to determine whether country and method affected the data obtained from the analyzed theses. The analysis of the data showed that the US-based theses were structured in accordance with the established criteria in all aspects except for purpose and importance. Method did not affect consistency with the criteria. The results of the study are anticipated to guide graduate students, thesis advisors, and researchers preparing theses and articles.
AtıfScopus3WoS2OpenAlex4İncele - MakaleAçık Erişim2022Scopus SJRQ2Preliminary investigation of gene expression levels of PAPP-A, STC-2, and HIF-1α in SARS-Cov-2 infected patients
Karabulut Uzunçakmak, Sevgi; Naldan, Muhammet Emin; Dirican, Ebubekir; Kerget, Ferhan; Halıcı, Zekai
Background: Coronavirus-19 is still considered a pandemic that influences the world. Other molecular alterations should be clearer besides the increasing cytokine storm and pro-inflammatory molecules. Hypoxic conditions that induce HIF-1α lead to stimulate gene expression of STC-2 that targets PAPP-A expression. This study aimed to determine gene expression levels of PAPP-A, STC-2, and HIF-1α in COVID-19 infection. We also aimed to reveal the relationship of these genes with laboratory and clinical data of COVID-19 patients. Materials and Results: We extracted RNA from peripheral blood samples of COVID-19(+) and COVID-19(−) individuals. The real-time PCR method was used to measure mRNA expression of PAPP-A, STC-2, and HIF-1α. Gene expression analysis was evaluated by the 2−ΔΔCt method. PAPP-A, STC-2, and HIF-1α mRNA expressions of severe patients were higher than healthy individuals (p = 0.0451, p = 0.4466, p < 0.0001, respectively). Correlation analysis of gene expression patterns of severe patients demonstrated a positive correlation between PAPP-A and STC-2 (p < 0.0001, r = 0.8638). Conclusion: This is the first study that investigates the relation of PAPP-A, STC-2, and HIF-1α gene expression in patients with COVID-19 infection. Besides the routine laboratory findings, PAPP-A, STC-2, and HIF-1α mRNA expressions may be considered to patients’ prognosis as a sign of increased cytokines and pro-inflammatory molecules.
AtıfScopus6WoS6OpenAlex8İncele - MakaleYalnız künye2022Scopus SJRQ4Analysing the potential of transport triggered architecture for lattice-based cryptography algorithms
Akçay, Latif; Yalçın, Berna Örs
Lattice-based structures offer numerous possibilities for post-quantum cryptography. Recently, many post-quantum cryptography algorithms have been built on hard lattice problems. The three of the remaining four algorithms in the final round of the NIST Standardization Process rely on lattice-based methods. However, suitable processor architectures for these algorithms have not been sufficiently investigated. This study examines the potential advantages of transport triggered architecture for these algorithms. We compare popular 64-bit RISC-V processors with our conceptual transport triggered architecture processor over reference software implementations. Our processor provides better results than RISC-V competitors, regardless of the algorithm. It seems to be up to 3× faster, 1.6×–2× smaller, and consumes 1.3×–3.6× less energy than the compared RISC-V cores. Thus, an alternative base architecture is proposed for post-quantum cryptography processor development for embedded systems. The most critical shortcoming of the proposed architecture is the lack of compatible intellectual property core support for system-on-chip designs. We share comparative analyses with test results for different core configurations.
AtıfScopus3WoS2İncele - MakaleAçık Erişim2022Scopus SJRQ2Anatomy, trichome micromorphology and phytochemical profile of Stachys rizeensis R.Bhattacharjee from Turkey
Gerçek, Yusuf Can; Acar Şahin, Aydan; Ecem Bayram, Nesrin; Çelik, Saffet; Sefalı, Abdurrahman; Gıdık, Betül; Cevahir Öz, Gül; Pınar, Nur Münevver
In recent years, the popularity of natural products and natural product formulations has increased due to their beneficial effects on health. As a part of this trend, Lamiaceae family members have attracted attention due to their rich bioactive properties. Although the Stachys rizeensis R.Bhattacharjee plant is an endemic plant species in Turkey, no studies focus on its characterization. Hence, the present study aims to demonstrate the anatomical, morphological and phytochemical characterization of S. rizeensis in Turkey. In the first stage of the study, anatomical and trichome morphological characterization was performed to contribute to the taxonomic definition of S. rizeensis was found to be anatomically different from some other previously studied Stachys sp. by showing lacunar collenchyma type, uncertain cambium at the corners, two or three rows of endodermis in certain areas in the stem and two rows of palisade parenchyma, capitate and peltate glandular trichomes in the leaf. In the second stage, the phenolic profile, total phenolic/flavonoid content and antioxidant activity of the plant extracts prepared using solvents with different polarities (ethanol, methanol, water, ethyl acetate and hexane) were tested to determine the phytochemical content of the plant. The phytochemical analysis supported by chemometric analysis (PCA and HCA) revealed that methanol was the most efficient organic solvent for the extraction of the phytochemical compounds of the plant. Additionally, it was observed that chlorogenic acid (1842.40–217,086.19 mg/kg), verbascoside (2591.43–204,429.81 mg/kg), luteolin (3579.56–88,636.14 mg/kg) and kaempferol (9706.30–50,340.93 mg/kg) compounds were present at maximum levels in this plant, in which 31 different phenolic compounds were scanned using LC-MS/MS. In addition, results obtained from the phytochemical analysis revealed that S. rizeensis is a valuable plant that can be used for medical protection/treatment and that it could also have a variety of culinary applications. The present study served as the first original report regarding the chemical profile and anatomical characteristics of S. rizeensis (Lamiaceae) from Turkey.
AtıfScopus4WoS4OpenAlex4İncele - MakaleAçık Erişim2022Scopus SJRQ1Techno-economic assessment of a synthetic fuel production facility by hydrogenation of CO2 captured from biogas
Tozlu, Alperen
In this study, a thermodynamic and economic analysis of a synthetic fuel production facility by utilizing the hydrogenation of CO2 captured from biogas is carried out. It is aimed to produce methanol, a synthetic fuel by hydrogenation of carbon dioxide. A PEM electrolyzer driven by grid-tie solar PV modules is used to supply the hydrogen need of methanol. The CO2 is captured from biogas produced in an actual wastewater treatment plant by a water washing unit which is a method of biogas purification. The required power which is generated by PV panels, in order to produce methanol, is found to be 2923 kW. Herein, the electricity consumption of 2875 kW, which is the main part of the total electricity generation, belongs to the PEM system. As a result of the study, the daily methanol production is found to be as 1674 kg. The electricity, hydrogen and methanol production costs are found to be $ 0.043 kWh−1, $ 3.156 kg−1, and $ 0.693 kg−1, respectively. Solar availability, methanol yield from the reactor, and PEM overpotentials are significant factors effecting the product cost. The results of the study presents feasible methanol production costs with reasonable investment requirements. Moreover, the efficiency of the cogeneration plant could be increased via enriching the biogas while emissions are reduced.
AtıfScopus34WoS32OpenAlex37İncele - MakaleAçık Erişim2022Scopus SJRQ2Estimation of soil temperatures with machine learning algorithms—Giresun and Bayburt stations in Turkey
Guleryuz, Didem
Since soil temperature (ST) is one of the most critical determinants affecting the soil’s physical and chemical properties, the studies on soil temperature estimation increase with the widespread use of deep learning and machine learning algorithms. This study estimates soil temperature at four depths for Giresun and Bayburt stations in Turkey employing the Bayesian Tuned Gaussian Process Regression (BT-GPR), Bayesian Tuned Support Vector Regression (BT-SVR), and Long Short Term Memory (LSTM) models. The stations were selected from semiarid (Bayburt station) and very humid (Giresun station) climates to compare the models’ performance and measure their applicability in different climate classes. Common meteorological indicators were determined as input parameters in the developed models, and a five-and-a-half-year daily dataset was used for all models. This paper represents a novel scheme to optimize the hyperparameters of kernel functions for GPR and SVR models using the Bayesian optimization method to expand predictive efficiency. The developed GPR and SVR models’ outputs are compared with LSTM via three statistical metrics comprising the root mean square error (RMSE), mean absolute error (MAE), and the coefficient of determination (R2). The results show that the BT-GPR model has a superior estimation ability than other developed models for the two stations. The daily ST estimation with the highest accuracy was obtained at a 5-cm depth using BT-GPR at Giresun station (RMSE = 0.0439, R2 = 0.9535, MAE = 0.0344 in the testing phase) and Bayburt station (RMSE = 0.0525, R2 = 0.9438, MAE = 0.0412 in the testing phase). These outcomes provide helpful benchmarking guidance for future soil temperature investigation at various depths across the selected regions.
AtıfScopus12WoS14OpenAlex21İncele - MakaleAçık Erişim2022Scopus SJRQ2Androsace artvinensis sp. nov. (Primulaceae): A new species from northeastern Anatolia, Turkey
Sefali, Abdurrahman; Yapar, Yakup
Androsace artvinensis (Primulaceae) from Artvin province (northeastern Anatolia) has been described as a new species to science. The new species is morphologically similar to A. armeniaca var. macrantha but differs from it by several morphological characters, such as bracts shape, calyx (calyx length and lobes), corolla (corolla length, lobes, and indumentum), hairs, leaves, pollen features, and habitat preference. Diagnostic morphological characteristics, a full description, and a distribution map are provided.
AtıfScopus3WoS3OpenAlex2İncele - BildiriYalnız künye2022SpectrumChain: An Efficient Spectrum Management Framework in Blockchain-Enabled Flexible SDONs
Guler, Evrim; Karakus, Murat; Uludag, Suleyman
Huge potentials of optical networks provide an excellent choice in meeting the exponential growth in bandwidth demand. In particular, Elastic Optical Networks (EONs), with its promising potentials in increased availability, failure resilience, load-balancing, new use cases for on-demand opportunities, and efficient resource allocations, are good candidates for the future high-speed networks. When EONs are augmented with the emerging Software Defined Networking (SDN), that decouples the data and control planes, an agile and synergistic combination emerges under a general term of SDN-based optical networking (SDON), albeit with operational challenges. In this paper, we introduce a blockchain-enabled QoS-based inter-Internet Service Provider (ISP) routing coordination framework for SDONs, SpectrumChain (SC), to eliminate centralized mediators and reduce QoS signaling overhead. Experimental results show that the SC framework can effectively handle the QoS-enabled inter-ISP routing in SDON architecture in terms of flow setup time, message overhead, and requests serviced as compared to the traditional approaches.
AtıfScopus6WoS5OpenAlex6İncele - MakaleAçık Erişim2022Scopus SJRQ1High optical response NiO, Pd/NiO and Pd/WO3 hydrogen sensors
Çoban, Ömer; Tekmen, Süleyman; Gür, Emre; Tüzemen, Sebahattin
In this study, NiO and WO3 oxide semiconductors were fabricated on glass substrates by RF Magnetron Sputtering technique. Structural and optical characterizations of the semiconductors were performed using XRD, SEM, and optical absorption measurements. NiO and WO3 thin films were occasionally coated with palladium. In order to investigate the optical response of these semiconductors under hydrogen gas exposure, an optical gas sensor test system was installed and programmed. In both of the coated and uncoated cases, optical absorption changes due to hydrogen gas exposure on the surface were investigated. It was observed that these changes occur between 450 and 850 nm wave lengths range. The absorption in the NiO semiconductor was reduced between these wave lengths, while the absorption was increased in the WO3 semiconductor. In the uncoated state, only NiO gave an optical response to hydrogen gas. While the palladium coated NiO (Pd/NiO) sensor had the best response and recovery times of respectively 70 s and 206 s for 2% fraction of H2 gas at 300 °C constant temperature, the Pd/WO3 sensor gave the best response time of 340 s. Palladium coating resulted in approximately 150% increase in the responses of the NiO sensors at higher H2 concentration. The lower limit of H2 sensing of the Pd/NiO sensors at 300 °C was at the H2 fraction of 0.05%, while for Pd/WO3 sensors this value was 0.025%.
AtıfScopus26WoS25OpenAlex26İncele - MakaleYalnız künye2022Scopus SJRQ4The mediating role of self-efficacy between emotional intelligence and job satisfaction of primary school teachers; [Le rôle médiateur de l'auto-efficacité entre l'intelligence emotionnelle et la satisfaction au travail des enseignants du primaire]
Sökmen, Yavuz; Sarikaya, İsmail
Introduction: In this study, it was analyzed whether self-efficacy has a mediating role between the emotional intelligence and job satisfaction of primary school teachers. Objective: It is to test the relationships between primary school teachers job satisfaction, self-efficacy and emotional intelligence levels. Method: A path analysis was performed on a sample of 252 primary school teachers. Results: It was found that self-efficacy mediated the relationship between emotional intelligence and job satisfaction. Conclusion: Based on the findings of the study, the relationships between emotional intelligence, job satisfaction and self-efficacy were discussed in the literature and various suggestions were made to concerned future researchers and practitioners.
AtıfScopus15WoS7OpenAlex17İncele - MakaleAçık Erişim2022Scopus SJRQ2Tepegöz: Bayburt’s Harsh Winter; [Bayburt’un Kara Kışı: Tepegöz]
Koç, Tuğba Akkoyun
Epics, in which various events such as war, famine, internal political conflicts, and natural disasters, have deep traces in the minds of nations and are conveyed through generations with mythological elements that are not too far from the Dede Korkut Stories. Mythic period traces found in the stories have formed a layered structure equipped with concentrated information. Although chronologically, the first layer is actually the last layer added, it is the most understandable and appealing layer to the general reader. The latter layers are much deeper because its context diverges a little further from the reader. In order to reach the deep structure, as aimed in this study, the method of discourse analysis, which focuses on the archeology of the text, is based on the dominance of the ideology on the text, and the perspectives of linguistic anthropology has been used; since the words and structures they form in the texts come into existence not by chance but by “selection”, These two fields of study are always in an interaction and exchange with each other. According to research, climate plays a very important role in the formation of civilization and interacts with their social, economic, and political elements. Thus, climate changes and their consequences (famine, migration, etc.), wars, important warriors, opinion leaders, and victories throughouth the world can be conveyed through literary texts. When the layered structure in the Tepegoz story is examined, the connection between climate-human interaction is clearly seen. In this context, the story where Basat killed Tepegöz, has been analyzed with the support of data from various disciplines such as environmental history, medicine, climatology, zoology, geology, geography, and toponym, in accordance with the interdisciplinary dimension of discourse analysis; as a result, the Tepegoz-harsh winter link was revealed. As per the concept of Tepegöz; it has been observed that there is reference to the long and harsh winters that prevent access to a healthy metabolism, accommodation, and eating, which are basic human needs. It is possible to assume that “fantastic” beings like Cyclops, which can be found in myths, epics, fairy tales and legends, express a non-human threat that brings human life to an end in various ways.
AtıfOpenAlex4İncele - MakaleYalnız künye2022Scopus SJRQ2Optimized Machine Learning Algorithms for Investigating the Relationship Between Economic Development and Human Capital
Ozden, Erdemalp; Guleryuz, Didem
In Economic Development, human capital was previously seen as production factors but gradually evolved into endogenous growth theories. Most of the previous studies have examined the relationships between economic development and human capital via econometric models. Since this relationship is usually nonlinear and machine learning (ML) models can resolve it better, this study investigates the relationships by employing ML methods to provide a new perspective. For this purpose, the optimized ML methods, namely Bayesian Tuned Support Vector Machine and Bayesian Tuned Gaussian Process Regression (BT-GPR), were performed to develop the prediction model for economic development. The hyperparameters have been optimized with the Bayes method by using different kernel functions to increase SVM and GPR methods' predictive performance. The Multiple Linear Regression model has been employed to make a comparison as an econometric model. The performance of the models is evaluated using three statistical metrics, namely, the root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R2). The BT-GPR with the exponential kernel model has superior prediction ability with the highest accuracy (R2: 0.9727, RMSE: 0.4022, MAE: 0.3728 in the testing phase). The study shows that the BT-GPR model increases the accuracy of R2 6.4%, RMSE 10.7%, and MAE 1% compared with other developed models.
AtıfScopus27WoS18OpenAlex30İncele - MakaleAçık Erişim2022Scopus SJRQ3Approximating Functions in the Power-Type Weighted Variable Exponent Sobolev Space by the Hardy Averaging Operator
Ayazoglu, Rabil; Ekincioglu, Ismail; Şener, S. Şule
We investigate the problem of approximating function f in the power-type weighted variable exponent Sobolev space (Formula presented), by the Hardy averaging operator (Formula presented). If α(.) x 0 the function f lies in the power-type weighted variable exponent Sobolev space (Formula presented) (0, 1), it is shown that (Formula presented), where C is a positive constant. Moreover, we consider the problem of boundedness of Hardy averaging operator A in power-type weighted variable exponent grand Lebesgue spaces (Formula presented) (0, 1). The sufficient α(.) criterion established on the power-type weight function α(.) and exponent p(.) for the Hardy averaging operator to be bounded in these spaces.
AtıfScopus3WoS4OpenAlex3İncele - MakaleYalnız künye2022Scopus SJRQ1Investigation of antibacterial, antifungal, antibiofilm, antioxidant and anticancer properties of methanol extracts of Salvia marashica İlçim, Celep & Doğan and Salvia caespitosa Montbret & Aucher ex Benth plants with medicinal importance
Bostanci, Maside Temiz; Bulbul, Ali Savas; Celik, Ibrahim Seyfettin; Kocabas, Yusuf Ziya; Burhan, Hakan; Bayat, Ramazan; Sen, Fatih; Zakariae, Nilofar; Esmaeili, Roghayeh; Jafari, Hedayat
In this study, Antimicrobial, Antifungal and Antibiofilm activity tests on 16 bacteria and 2 fungi of Salvia marashica İlçim, Celep & Doğan and Salvia caespitosa Montbret & Aucher ex Benth species were performed by Agar Well Diffusion and Microdilution methods. Salvia species showed sensitivity with a zone diameter of 12–16 mm. Concentrations of 0.5 mg/ml to 16 mg/ml by the dilution method were used to determine the Minimum inhibited concentration (MIC) and Minimum bactericidal concentration (MBK). The MIC values of the plants are mostly 0.5 mg/ml - 4 mg/ml and MBC values are between 0.5 mg/ml - 8 mg/ml. Antifungal activity findings are remarkable on the species and it has been observed to have very high effects especially on Candida parapsilosis. When the antioxidant research findings are examined; It was observed that Salvia marashica and Salvia caespitosa plants have approximately 75% antioxidant activity at 1 mg/ml, and findings mostly directly proportional between concentrations and antioxidant activity capacity were recorded. MCF-7 and HUVEC cell lines were used to investigate anticancer activity properties. In line with the findings, while the IC50 value of Salvia marashica on the MCF-7 Cell line was 0.125 mg/ml, it was 1.65 mg/ml in the HUVEC cell line, while the IC50 value of Salvia caespitosa on the MCF-7 Cell line was 0.115 mg/ml in the HUVEC Cell line. It was found to be 9.87 mg/ml. It has been proven that both Salvia species have a cytotoxic effect on the MCF-7 Cell line.
AtıfScopus21WoS16OpenAlex23İncele - MakaleYalnız künye2022Scopus SJRQ2Brand portfolio strategies effects on consumers' attitude
Yilmazel, Sefa Emre; Özer, Leyla
Purpose: The aim of this study is to determine the effects of brand components (CBBE, brand fit, brand image, brand reputation, brand familiarity) on consumers brand portfolio attitude via perceived risk (for two main portfolio strategies). Design/methodology/approach: The study used a structured questionnaire to collect primary data from 636 consumers who made purchases from companies using house of brand (318) and branded house strategy (318). By conducting reliability and validity analysis, the model of this study was tested with confirmatory factor analysis and path analysis methods, using structural equation modeling. Findings: According to the results of the path analysis, the effects of CBBE and brand reputation on brand attitude were confirmed for both house of brand and branded house strategy. Moreover, the full and partial mediating effect of perceived risk was proven in the relationships. Research limitations/implications: One of the limitations of the study is determining a portfolio of brands for each strategy and collecting data for these brands. In addition, since the number of consumers using brand portfolios could not be reached in the study, data could be collected using the purposeful convenience sampling method. For this reason, it is thought that research conducted with the data obtained through systematic sampling methods can yield more reliable results. Practical implications: Managers of companies with a brand portfolio should work on a main strategy that enhances CBBE and brand reputation regardless of the strategy they use. After these two variables, the variable that portfolio managers need to address is brand fit. Originality/value: It will offer different perspectives in terms of understanding which portfolio strategy is needed, and which predecessors and outputs can be produced. Also, the findings of the research will produce important results to reduce the perceived risks of consumers and increase their positive attitudes toward brand portfolios.
AtıfScopus7WoS6OpenAlex8İncele