Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Dertli, Enes(12)
- Şahin, Engin(9)
- Bayram, Sinan(8)
- Dirican, Ebubekir(8)
- Ertugrul, Mehmet(8)
- Kaya, Yunus(8)
- Sefali, Abdurrahman(8)
- Kul, Sinan(7)
- İspirli, Hümeyra(7)
- Ayata, Ümit(6)
- Kutlu, Naciye(6)
- Gerçek, Yusuf Can(5)
- Kömür, Gökhan(5)
- Ramahi, Omar M.(5)
- Çelik, Saffet(5)
- Özdemir, Akın(5)
- Artar, Musa(4)
- Ayazoglu, Rabil(4)
- Can, Zehra(4)
- Ecem Bayram, Nesrin(4)
- Ekmekyapar Torun, Fatma(4)
- Hasar, Ugur C.(4)
- Hasar, Ugur Cem(4)
- Kamiloğlu, Aybike(4)
- Karaali, Rabi(4)
- Keskin, Savaş(4)
- Ozden, Erdemalp(4)
- Sunaoglu, Serife Kazanci(4)
- Taylan, Osman(4)
- Ustabulut, Mete Yusuf(4)
- Akkoyunlu, Ebubekir(3)
- Apak, Ömer Ceyhun(3)
- Aras, Selim(3)
- Battal, Fetullah(3)
- Carbas, Serdar(3)
- Cebeci, Fatma(3)
- Gökçe, H.S.(3)
- Hırca, Tuğçe(3)
- Izginli, Mucahit(3)
- Kadakal, Huriye(3)
Yayınlar
- BildiriYalnız künye2022Scopus SJRQ2Ultrasonicate-assisted preparation of eumelanin-loaded nano/microparticles based on polylactide stereocomplex
Putri, Oceu Dwi; Petchsuk, Atitsa; Bayram, Sinan; Opaprakasit, Pakorn
The utilization of ultrasonication in the preparation of polymeric nano/microparticles has attracted vast attention due to its simplicity with low cost and high energy efficiency. The occurrence of acoustic cavitation generated by the ultrasonication process can enhance droplet disintegration, allowing the improved stability of emulsions. In this study, eumelanin-loaded nano/microparticles were prepared by employing polylactide stereocomplex (sc-PLA) formed by blending of poly(D-lactide-caprolactone-D-lactide), P(DLA-b-CL-b-DLA), triblock copolymer with linear poly(L-lactide), PLLA. The particles were prepared through an oil in water emulsion (O/W) technique followed by a solvent evaporation. The effect of ultrasonication on the encapsulation efficiency and physicochemical properties of the nano/microparticles was evaluated. The results showed that ultrasonication treatment could control nano/microparticles' shape, size, and size distribution, which enhanced the particle stability and the entrapment efficiency of eumelanin. Particle size distribution of ultrasound-assisted nano/microparticles was in a range of 0.38–135 μm, while those without ultrasonication had a broader distribution from 0.38–153 μm. Higher zeta potential was also observed in the ultrasound-assisted nano/microparticles, reflecting their higher suspension stability. The ultrasonication treatment led to higher eumelanin encapsulation efficiency (46.6%) with higher thermal stability and crystallinity, promoted by the formation of higher contents of the stereocomplex crystallites. The results confirm that ultrasonicate-assisted emulsification can be effectively used to fabricate the functional eumelanin-loaded nano/microparticles.
AtıfScopus5OpenAlex3
İncele - 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.
AtıfScopus34WoS32OpenAlex37
İncele - 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 - Kitap BölümüYalnız künye2022Non-Family Managers and HR Practices of Family Firms
Yazici, Ömer
Family firms have one special factor that makes them unique and competitive compared to non-family firms, and that is family involvement. Family firms are composed of management, family, and ownership. While this composition often has many advantages, it also has some downfalls. Family involvement has a significant impact on the behavior of the company, more specifically on the human resource (HR) management practices of the company. As a result, family firms have to deal with nepotism, self-dealing, and entrenched management issues to hire and retain professional non-family managers and other white-collar workers. Family firms are intended to be the career center for family employees (Bloemen-Bekx et al. 2019). Therefore, family firms have different HR compositions. There are mainly three types of employees in family firms; first, the shareholder family members and their heir (ownership), second, the other family members and relatives (family), and third, the non-family employees (management). Non-family employees are divided into two categories, managers and workers. Although family firms have a tendency to assign family members to crucial positions at the firm (Deloitte and Touche Study 1999), non-family employees are hired for other executive and managerial positions, which is more crucial for family firms (Chua et al. 2003). Considering all these challenges and difficulties due to family involvement in employee relations, researchers raise the question of whether “family firms are good employers” (Neckebrouck et al. 2018). Family firms diverge from non-family firms with their long-term orientation and caring approach to their employees. This caring approach is proven in downsizing studies. Researchers show that during crises and downsizing practices, family firms lay off fewer employees than non-family firms (Stavrou et al. 2007). Non-family employees are keystones of the family firm’s growth and necessary for each growing family firm. Therefore, the employment of non-family members will affect the sustainability of the firm. While it is important for all types of companies, it is crucial for family firms to have committed and devoted non-family employees. Hiring non-family managers is usually a result of a limited family employee presence during the growth of the company. Controlling growth due to a limited family member presence and running a firm with only family managers would result in informal structures, peculiar culture, and limited growth. Non-family managers are sometimes hired as conflict resolution when there is a conflict of interest during the employment of family members (Lubatkin et al. 2005). Hence mostly non-family managers are hired if there is a formalization process in progress (Zhang and Ma 2009). Also, most first non-family managers in the firm are CEOs. Furthermore, family firms with financial struggles tend to employ a non-family CEO rather than a family CEO (Bocatto et al. 2010). According to a study done with Italian firms, family firms prefer to nominate non-family CEOs rather than family CEOs (Salvato et al. 2012). Additionally, in growth times, family firms also prefer non-family CEOs over family CEOs. In conclusion, while family firms are able to fill managerial positions, it is empirically shown that the growth of family firms is correlated with non-family managers (Fang et al. 2015).
- 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 Erişim2022Does inquiry-based learning model improve learning outcomes? A second-order meta-analysis
Öztürk, Bilge; Kaya, Metin; Demir, Mustafa
This research study aims to utilize a second-order meta-analysis procedure to synthesize the effects of inquiry-based learning model (IBLM) on learning outcomes. An extensive systematic review process resulted in the inclusion of 10 meta-analyses conducted between 2015 and 2022 with minimal overlap between primary studies. The results revealed that IBLM has a medium-level positive effect (d = 0.62) on learning outcomes. The analyses showed that mobile inquiry-based model, learning cycle model and conceptual change text model have high-level positive effect on learning outcomes. Moderator analyses revealed that the effect sizes were not significantly moderated by grade level, content area, location, quality, primary research report type, and publication bias. Limitations, educational implications, and directions for future research are provided.
AtıfScopus33OpenAlex47İncele - 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 künye2022(m1, m2)-Geometric Arithmetically Convex Functions and Related Inequalities
Kadakal, Mahir
In this manuscript, we introduce and study the concept of (m1, m2)-geometric arithmetically (GA) convex functions and their some algebric properties. In addition, we obtain Hermite-Hadamard type inequalities for the newly introduced this type of functions whose derivatives in absolute value are the class of (m1, m2)-GA-convex functions by using both well-known power mean and Hölder’s integral inequalities.
AtıfScopus2İncele - 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 - MakaleAçık Erişim2022Scopus SJRQ4Isolation of Distinct Lactobacillaceae spp. with Functional Characteristics from Traditional Sourdough Samples; [Geleneksel Ekşi Hamur Örneklerinden Fonksiyonel Özelliklere Sahip Farklı Lactobacillaceae spp. İzolasyonu]
İspirli, Hümeyra; Dertli, Enes
Lactic Acid Bacteria (LAB) were isolated from traditional sourdough samples, and functional properties of selected LAB species were determined. Five distinct strains Limosilactobacillus fermentum LR1, Lacticaseibacillus rhamnosus LR2, Levilactobacillus senmaizukei CE37, Lactiplantibacillus plantarum CE48 and Limosilactobacillus reuteri KD44A were identified following the genotypic discrimination of hundred isolates. Presence of bacteriocin genes in identified species was determined by PCR, and sourdough isolates have been shown to carry bacteriocin genes although they vary according to species. Exopolysaccharide (EPS) production tests showed that the amount of EPS production varies in different media and different incubation conditions. Antimicrobial effects of 5 different LAB species were determined against Bacillus cereus BC 6830, which cause rop problems, and other pathogen species and also molds isolated from bread. Amylolytic activities of isolates, which are important in terms of technological roles, were determined genotypically and phenotypically. Finally, the phytase and phosphatase activities of these species were studied. This study was aimed to unveil the functional sourdough LAB species to be used for industrial purposes.
AtıfScopus4OpenAlex3
İncele - 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.
AtıfScopus21WoS16OpenAlex23
İncele - 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 - MakaleYayıncıda açık erişim2022Scopus SJRQ1Analysis of mitochondrial DNA cytochrome-b (CYB) and ATPase-6 gene mutations in COVID-19 patients
Dirican, Ebubekir; Savrun, Şeyda Tuba; Aydın, İsmail Erkan; Gülbay, Gonca; Karaman, Ülkü
Coronavirus disease of 2019 (COVID-19) is a pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Mutations of mitochondrial DNA (mtDNA) are becoming increasingly common in various diseases. This study aims to investigate mutations in the cytochrome-b (CYB) and adenosine triphosphatase-6 (ATPase-6) genes of mtDNA in COVID-19 patients. The association between mtDNA mutations and clinical outcomes is investigated here. In the present study, mutations of the mtDNA genes CYB and ATPase-6 were investigated in COVID-19 (+) (n = 65) and COVID-19 (−) patients (n = 65). First, we isolated DNA from the blood samples. After the PCR analyses, the mutations were defined using Sanger DNA sequencing. The age, creatinine, ferritin, and CRP levels of the COVID 19 (+) patients were higher than those of the COVID-19 (−) patients (p = 0.0036, p = 0.0383, p = 0.0305, p < 0.0001, respectively). We also found 16 different mutations in the CYB gene and 14 different mutations in the ATPase-6 gene. The incidences of CYB gene mutations A15326G, T15454C, and C15452A were higher in COVID-19 (+) patients than COVID-19 (−) patients; p < 0.0001: OR (95% CI): 4.966 (2.215−10.89), p = 0.0226, and p = 0.0226, respectively. In contrast, the incidences of A8860G and G9055A ATPase-6 gene mutations were higher in COVID-19 (+) patients than COVID-19 (−) patients; p < 0.0001: OR (95%CI): 5.333 (2.359−12.16) and p = 0.0121 respectively. Yet, no significant relationship was found between mtDNA mutations and patients' age and biochemical parameters (p > 0.05). The results showed that the frequency of mtDNA mutations in COVID-19 patients is quite high and it is important to investigate the association of these mutations with other genetic mechanisms in larger patient populations.
AtıfScopus14WoS16OpenAlex21İncele - MakaleYalnız künye2022Scopus SJRQ1Characterisation and functional roles of a highly branched dextran produced by a bee pollen isolate Leuconostoc mesenteroides BI-20
Yilmaz, Mustafa Tahsin; İspirli, Hümeyra; Taylan, Osman; Taşdemir, Volkan; Sagdic, Osman; Dertli, Enes
Lactic Acid Bacteria (LAB) from different niches can be responsible for the production of distinct exopolysaccharides (EPS) that might possess important structural and technological features. In this respect, the aim of this study was to isolate an EPS producer LAB strain from bee pollen environment. Leuconostoc mesenteroides BI-20 with a slimy-mucoid colony morphology was identified from bee pollen and the structural, technological and functional characteristics of EPS produced by this strain were determined. EPS BI-20 was a highly branched dextran containing 20% (1 → 3)-linked α-D-glucose branches determined by 1H and 13C NMR analysis. The presence of (1 → 6)/(1 → 3)-linked α-D-glucose linkages in dextran BI-20 was also confirmed by FTIR analysis. Dextran BI-20, with a molecular weight of 1 × 108 Da, possessed strong thermal properties, amorphous nature and highly branched and fibrous microstructural characteristics determined by DSC, TGA, XRD and SEM analysis, respectively. In terms of functional roles, dextran BI-20 demonstrated strong antioxidant capacity detected by ABTS and CUPRAC tests. Finally, no digestion was observed in dextran BI-20 under simulated gastric conditions. Results of this study unveiled techno-functional characteristics of dextran BI-20 produced by a bee pollen isolate LAB strain.
AtıfScopus39WoS36OpenAlex39İncele - MakaleYalnız künye2022Scopus SJRQ2Photocatalytic activity of cobalt aluminate nanoparticles synthesized by microwave-assisted combustion method
Karakaş, İbrahim Hakkı; Karcıoğlu Karakaş, Zeynep; Ertuğrul, Mehmet
Cobalt aluminate is one of the most widely-used spinel aluminate types. It is known that various structural, magnetic and morphological properties of spinel ceramics can vary depending on the synthesis technique and the starting chemicals used. In this study, initially, heat treatment was applied to cobalt aluminate nanoparticles synthesized by the microwave-assisted combustion method and the effects of the applied heat treatment on the structural properties were investigated. Characterization studies showed that cobalt aluminate spinel pigments were successfully synthesized. The optimum heat treatment temperature was determined as 700 °C. Then, the synthesized cobalt aluminate nanoparticles were used as photocatalysts for dye removal by photocatalytic oxidation from a synthetic wastewater containing Astrazon red textile dye and their photocatalytic activity was investigated at different catalyst dosages. Moreover, the same particles were also produced by conventional combustion technique. Then, their photocatalytic activities were studied and the data were compared with the results obtained from the experiments made with the samples produced with microwave assisted combustion method under the same experimental conditions. The results show that cobalt aluminate nanoparticles synthesized by microwave assisted combustion exhibit a better photocatalytic activity. In experiments performed with samples produced via microwave-assisted combustion method, all dyestuff content in the solution containing 50 mg/L dye was completely removed under UV irradiation for approximately 60 min. It was determined that the catalyst dosage had an effect on the reaction rate and the reaction was found to be compatible with the pseudo first order kinetic model.
AtıfScopus12WoS12OpenAlex13İncele - MakaleYalnız künye2022EVALUATING PROSPECTIVE ELEMENTARY SCHOOL TEACHERS’ WRITTEN AND ORAL ARGUMENTS ON ECOLOGY
Öztürk, Bilge; Okumuş, Seda
This study aimed to evaluate prospective elementary school teachers’ skills in creating written and oral arguments about the ecology. The case study method, one of the qualitative research approaches, was used. The study group consisted of 38 prospective elementary school teachers studying in the third year of an elementary teaching undergraduate program. As data collection tools, an expressions table containing ecology topics was designed by the researchers to evaluate the written argument creation skills of the participants and audio recordings of discussions were used to determine their oral argument creation skills. Descriptive analysis was used to analyze the data obtained in these ways. According to the findings of this research, the written and oral arguments of these prospective elementary school teachers were concentrated at a moderate level, but their oral arguments were at a higher level than their written arguments. It can be concluded that oral classroom discussions are more effective than written activities in creating arguments about the ecology.