Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Impact of Titania Phase Structure and Surface Reactivity on the Photocatalytic Degradation of Various Dyes and Textile Wastewater(National Institute of Science Communication and Policy Research, 2023) Yurtsever, Hüsnü Arda; İloğlu, Onur; Çiftçioğlu, MuhsinTitania (TiO2) powders have been prepared by precipitation method in different precipitation media which contain sulfate, nitrate or organic species. Photocatalytic degradation of different dyes and a real textile wastewater have been conducted with these powders along with commercial powder Degussa P25 for comparison. Ethyl alcohol (organic medium), sulfuric acid (sulfate medium) and nitric acid (nitrate medium) have been used to dissolve titanium precursor for the precipitation of TiO2 in ammonia solution. UV-Vis DRS and XPS results indicate that S doping in sulfate medium precipitated powder and N doping in nitrate medium precipitated powder has been occurred and the presence of S or N containing impurities on the grain boundaries have been improved light absorption of TiO2 significantly. However, these powders have exhibited low surface reactivities. The highest surface reactivity has been obtained with the powder precipitated in organic medium which also has the highest crystallite sizes (76 nm rutile and 34 nm anatase crystallites) with relatively low rutile weight percentage (10.0%). The surface-normalized rate constants of this powder are 0.02038 min-1.m-2 in real textile wastewater degradation and 0.0161 min-1.m-2 in methyl orange degradation, which are 0.01563 and 0.0091 min-1.m-2, respectively, for Degussa P25. Results have shown that this powder show 30-70% higher surface reactivities compared to Degussa P25. The main structural difference of organic medium precipitated powder and Degussa P25 has been found to be the anatase-rutile weight ratio and crystallite size of rutile phase whereas band gap energy of Degussa P25 is lower and other properties are not significantly different.Article Citation - WoS: 2Citation - Scopus: 3The Green-Tao Theorem and the Infinitude of Primes in Domains(Taylor & Francis, 2022) Göral, Haydar; Özcan, Hikmet Burak; Sertbaş, Doğa CanWe first prove an elementary analogue of the Green-Tao Theorem. The celebrated Green-Tao Theorem states that there are arbitrarily long arithmetic progressions in the set of prime numbers. In fact, we show the Green-Tao Theorem for polynomial rings over integral domains with several variables. Using the Generalized Polynomial van der Waerden Theorem, we also prove that in an infinite unique factorization domain, if the cardinality of the set of units is strictly less than that of the domain, then there are infinitely many prime elements. Moreover, we deduce the infinitude of prime numbers in the positive integers using polynomial progressions of length three. In addition, using unit equations, we provide two more proofs of the infinitude of prime numbers. Finally, we give a new proof of the divergence of the sum of reciprocals of all prime numbers.Article Citation - WoS: 3Citation - Scopus: 4Frequency-Specific Sensitivity of 3t3-L1 Preadipocytes To Low-Intensity Vibratory Stimulus During Adipogenesis(Springer, 2022) Baskan, Öznur; Sarıgil, Öykü; Meşe Özçivici, Gülistan; Özçivici, EnginAdipocyte accumulation in the bone marrow is a severe complication leading to bone defects and reduced regenerative capacity. Application of external mechanical signals to bone marrow cellular niche is a non-invasive and non-pharmaceutical methodology to improve osteogenesis and suppress adipogenesis. However, in the literature, the specific parameters related to the nature of low-intensity vibratory (LIV) signals appear to be arbitrarily selected for amplitude, bouts, and applied frequency. In this study, we performed a LIV frequency sweep ranging from 30 to 120 Hz with increments of 15 Hz applied onto preadipocytes during adipogenesis for 10 d. We addressed the effect of LIV with different frequencies on single-cell density, adipogenic gene expression, lipid morphology, and triglycerides content. Results showed that LIV signals with 75-Hz frequency had the most significant suppressive effect during adipogenesis. Our results support the premise that mechanical-based interventions for suppressing adipogenesis may benefit from optimizing input parameters.Book Part Designing Healthier Cities. an Empirical Study of the Ecosystem Functioning and Mortality in the Districts of Turin (italy)(Springer, 2022) Salata, StefanoThe twenty-first century is called “the age of the metropolises and cities” as they become the predominant living environments of human beings. Nonetheless, metropolitan areas are more vulnerable, for their intrinsic nature is dense and interconnected. The experience from the COVID-19 crisis teaches us how an epidemic outburst has been generated by reducing habitat at the planetary scale, and how the quality of the environment even affects the diffusion of the virus. But what is the relation between Health and Nature in urban areas? Is this relation so evident? Within this study, a preliminary assessment of the relations between urban environment and health will be evaluated by modelling the spatial distribution of the Habitat Quality in Turin and the mortality rates in the same areas. Data will be gathered at their maximum spatial precision, thus obtaining a reliable map of the distribution between the two indicators at the district level. Habitat Quality will be composed by the value of the supporting biophysical function and anthropic threats. Health will be evaluated using the death number in the statistical units and the accessibility of citizens to green areas. An overall assessment will be finally presented considering the simultaneous evaluation of spatial clusters and delineating how conservation and valorization measures can benefit from a site-specific evaluation of Ecosystem Services, while revealing their effects on human health.Article Citation - WoS: 1Citation - Scopus: 1Viability of 3t3-L1 Preadipocytes Is Modulated by the Applied Frequency but Not the Exposure Duration of Low Intensity Vibratory Stimulation(World Scientific Publishing, 2022) Baskan, Öznur; Özçivici, EnginMechanical forces are the integral determinants in cell and tissue homeostasis and regeneration, and they can affect numerous biological process from proliferation to fate determination. Mechanical forces that possess low magnitude and high frequency characteristics are also known as low intensity vibrations (LIVs). These signals were studied widely on many cell types for regenerative purposes, however most of these studies select components of LIV signals (e.g., magnitude, frequency, duration, etc.) arbitrarily. Here, we addressed the effect of LIV applied frequency, LIV daily exposure time and fate induction on the viability of preadipocyte 3T3-L1 cells. For this, we performed a frequency sweep that was ranging from 30Hz to 120Hz with 15Hz increments applied for 5, 10 or 20min during quiescent growth or adipogenesis for up to 10 days. Results suggest that the applied frequency and fate induction was an important determinant of cell viability while daily exposure time had no effect. These findings contribute to the effort of optimizing a relevant mechanical stimulus that can inhibit adipogenesis.Article Citation - WoS: 2Citation - Scopus: 6Towards Integration of the Finite Element Modeling Technique Into Biomedical Engineering Education(World Scientific Publishing, 2022) Mihçin, Şenay; Çıklaçandır, SametBiomedical engineering (BME) is a multidisciplinary field, resulting in a heavy course load from different fields. We hypothesize that the engineering curriculum be tailored according to the requirements of the BME profession. In this study, we focus on the teaching of the finite element modeling (FEM) technique by redesigning the course to address the needs of the BME profession by some custom-made changes to meet the unmet needs. After the completion of the course, evaluation methods of the students were analyzed and detailed over a survey providing feedback from the students. The surveys were related to the teaching the theory of FEM, the laboratory sessions, and the project sessions. The survey results were evaluated using statistical methods. The Pearson correlation coefficient showed a linear agreement between theoretical and practical sessions indicating efficient blending of skills because of the custom-made changes. The survey analysis showed that the students were in favour of the changes, allowing them to be more resourceful and confident with their skills. The positive results indicate a positive attitude among the students towards their profession. As the course design addresses the needs of the profession allowing students to fit in better, the students might follow their own profession after graduation. A wider follow-up study might be planned next to compare the results between who received tailor-designed courses and those who did not.Article Comparative Proteome Profiles of Methicillin-Resistant Staphylococcus Aureus in Response To Vanillic Acid and 2-Hydroxycinnamic Acid(Bentham Science Publishers, 2021) Keman, Deniz; Soyer, FerdaBackground: The ability of Staphylococcus aureus to cause severe infections and the difficulty of the treatments due to the multiple antibiotic resistance make this bacterium a lifethreatening human pathogen. This situation necessitates the exploration of novel antimicrobial compounds with known targets on bacteria. Phenolic acids naturally produced in plants as secondary metabolites are good candidates for being alternative antimicrobials for antibiotic-resistant bacteria. Objective: Investigation of protein profile of Methicillin-Resistant S. Aureus (MRSA) in the presence of subinhibitory concentrations of phenolic acids. Methods: MRSA was subjected to subinhibitory concentrations of Vanillic Acid (VA) and 2-Hydroxycinnamic Acid (2-HCA), separately, and the proteomic analyses were carried out by using liquid chromatography coupled to mass spectrometry. Results: Both phenolic acids elicited identification of differently expressed proteins that have roles in DNA replication, repair, RNA processing and transcription, protein synthesis, maintenance of cell homeostasis, several metabolic reactions in energy, carbohydrate and lipid metabolisms and also proteins related with the virulence and the pathogenicity of MRSA when compared with the control group. The numbers of the proteins identified were 444, 375, and 426 for control, VA-treated MRSA, and 2-HCA-treated MRSA, respectively, from which 256 were shared. While VA treatment resulted in 149 unidentified MRSA proteins produced in control, 2-HCA treatment resulted in 126 unidentified proteins. Data are available via ProteomeXchange with identifier PXD016922. Conclusion: The results obtained from this study might indicate the potential targets on bacteria and the effective use of phenolic acids in the battle with antibiotic-resistant pathogens.Conference Object A sustainable association case study: IFToMM member organization Turkey(Springer, 2022) Kiper, Gökhan; Söylemez, EresAs a member of IFToMM founded in 2011, Turkish Machine Theory Association’s (MakTeD) structure has put special emphasis on sustainability of the association and initiated several activities for improving the quality of education and research in mechanism and machine science area, hence supporting the SDG4 Quality Education of the UN. This paper presents the activities and methodologies of MakTeD. The paper starts with a brief history of mechanism and machine science in Turkey. In 10 years MakTeD organized 4 symposiums, 1 conference, 4 summer/winter schools, 8 workshops and hosted an IFToMM Executive Council meeting. Each chapter of the biyearly held National Symposium on Theory of Machines is held by a different university and especially newly established and the universities in relatively smaller cities are prioritized in order to promote those universities and to contribute to development of these universities. Especially the summer/winter schools and workshops have a widespread impact on mechanism and machine science education and research at the universities and institutions. MakTeD also contributes to the community with published books and support programs for young researchers.Article Traditional Dwellings of Gölde (i̇ncesu): a Rural Heritage in the Process of Change(Routledge, 2021) Eken, Esra; Kul, Fatma NurşenGölde, officially named İncesu, is a rural settlement located in Aegean Anatolia. Before the population exchange between Greece and Turkey in 1923, Gölde hosted both Orthodox Rum and Muslim Turkish communities. Despite out-migration since 1923, traditional life continued in the settlement with a small population that now comprises mostly elderly Turkish people. This paper aims to understand traditional Gölde dwelling units by analysing the influence of daily-life practices, customs, traditions and values through interviews with current locals and the oral testimonies of former Rum inhabitants. A site survey identified 136 traditional dwelling units, 68 of which are still inhabited. Site reconstruction analysis revealed the original condition of 90 dwelling units. These formed the primary focus of investigation. No major differences were found between houses originally belonging to the Rum and Turkish communities. However, the study identified significant adaptations of the dwelling units in line with changing socio-cultural conditions over time.