Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article A Comparative Study on Experimental and FEA-Based Simulation of Dry Sliding Wear Behavior of Boronized AISI 304 Stainless Steel at Elevated Temperatures(Pleiades Publishing Ltd, 2025) Gok, Mustafa Sabri; Kucuk, Yilmaz; Khosravi, Farshid; Gunen, Ali; Karakas, Mustafa Serdar; Guden, MustafaIn this study, the influence of boronizing on the high-temperature wear behavior of AISI 304 was examined experimentally and with FEA simulation. Boronizing, conducted at 950 degrees C for 3 h using the powder-pack boronizing technique, showed an approximately 7-fold increase in hardness compared to untreated sample. Boride layer characterization was performed using XRD, SEM, and EDS line analyses. Wear tests were performed at ambient temperatures of 25, 250, and 500 degrees C. While the wear rates of the untreated sample increased dramatically with increasing temperature, those of the boronized samples were significantly limited. FEA simulation using the Johnson-Cook fracture model demonstrated a high degree of consistency with the experimental wear profiles and this alignment enables reliable wear predictions. The oxide layer formation was observed on the worn surface of boronized samples during the tests at elevated temperatures, resulting in less plastic deformation.Article Geographical Classification and Characterization of Turkish Gemlik Virgin Olive Oils From Two Locations (Salihli - Manisa and Gemlik - Bursa) Based on Their Glyceridic Profiles(Innovhub SSI - Stazioni Sperimentali per l'Industria, 2025) Diraman, Harun; Ozdemir, DurmusThe Gemlik olive cultivar (which is grown for its fruit and oil, also known as the Trilya or Tirilye olive) is the major domestic cultivar of the Marmara region and originated in Bursa province on the Gulf of Gemlik. It has also been cultivated widely for over twenty years in other olive growing regions in Turkey and is the source of speculative claims by the domestic sector about the properties of its oil. In this study, VOO samples produced from Gemlik olive cultivar grown over two crop years in the two main locations (Salihli-Manisa n=10 and Gemlik -Bursa n=14) and reference samples from the Olive Research Institute-Borova/Izmir (n=2) were analysed using the common and approved capillary GC (Fatty Acid Composition-FA) and HPLC (Triacylglycerol Profile-TAG) methods. All data from both methods were classified with the most popular chemometrics methods (Principal Component Analysis, PCA and Hierarchical Cluster Analysis, HCA). The results of the glyceridic data from the PCA indicated that the changes of cumulative percentage were the reason for variance levels (based on PC1 and PC2) in VOO samples of between 61.75 and 77.93% for all data over the two crop years. According to the PCA biplot analysis for the two crop years, some major-minor compounds and calculated parameters from FAs and TAGs data played an effective role in the geographical characterisation and classification of Gemlik VOO from two different locations, Manisa and Bursa. Consequently, the FA and TAG profiles could be promising in determining the correct geographical classification of monocultivar Gemlik VOOs.Article The Infinitude of the Primes and Some Coloring Theorems(Taylor & Francis inc, 2025) Adibelli, Azem Berivan; Goral, HaydarWe first prove the infinitude of the primes via a special case of Rado's theorem whose proof is based on the infinite Ramsey theorem. In the proof, we use the colorings of the positive integers introduced by Levent Alpoge [1] and Andrew Granville [2]. Finally, using Rado's theorem for integral domains, we will give another proof for the infinitude of nonassociated prime elements in any unique factorization domain R with a few units.Article Poly(Ethylene Glycol)-Keratin Hydrogels Prepared Via Thiol-Maleimide Reaction(Polymer Soc Korea, 2025) Yalcin, Damla; Top, AybenThe mechanical properties of hydrogels have a profound effect on cellular responses in tissue engineering applications. In this study, poly(ethylene glycol)-keratin (PEG-KRTN) hydrogels with tunable mechanical properties were prepared by varying molar mass of the maleimide functionalized PEG in the thiol-maleimide chemistry. Reduced keratins were reacted with PEG-maleimides having 2000 Da and 6000 Da molar masses. Viscoelastic and physiochemical properties and cytocompatibility of these hydrogels were tested. Storage modulus values were obtained as 2613 +/- 254 Pa and 1313 +/- 345 Pa for PEG2000-KRTN and PEG6000-KRTN hydrogels, respectively. Strain sweep data indicate that the linear viscoelastic region (LVER) of the PEG6000-KRTN hydrogel spans up to 40% strain value, whereas it is limited to 10% critical strain for the PEG2000-KRTN hydrogel. PEG6000-KRTN hydrogel presented higher swelling ratios and porosity. CCK-8 test showed that both hydrogels promoted the proliferation of L929 mouse fibroblast cells and, hence, can be applied in soft tissue engineering.Article Investigation of the Effect of Solar Energy Use in Buildings on Reducing Carbon Dioxide Emissions(Inderscience Enterprises Ltd, 2025) Hancioglu, EbruThe aim of this study was to examine the reduction in CO2 emissions by using solar modules. In the article, the energy analysis of Narldere Nursing Home and Rehabilitation Centre (NNHRM) an exemplary public building in Izmir, was discussed. In this study, it was determined that if 1,500 kWp PV Panels were used, approximately 63.58% of the facility's electricity needs would be met by PV panels. It was revealed that by using the use of PV panels, an improvement of 6.98% in primary energy, 12.27% in CO2 emissions and 7.51% in PER would be achieved. The repayment period is calculated as 7.1 years.Article Cx32 Cellular Localization Is Related To Epithelial To Mesenchymal Transition in Breast Cells(Pleiades Publishing inc, 2025) Oz, Sercan; Turan, Fatma Basak; Yondem, Eyup; Pesen-Okvur, Devrim; Yalcin-Ozuysal, Ozden; Ozcivici, Engin; Mese, GulistanConnexins (Cx) play both gap junction-related and -independent roles in cells, and their localization is essential for their function in cellular processes. Besides membrane localization, connexins can also be localized to the cytoplasm and nucleus, especially in cancer cells. The differential localization of connexins including Cx32 was observed in different stages of cancers. Cx32 was upregulated and observed in cytoplasms of cells in lymph-node metastasis of breast cancer samples compared to primary tumors. However, the significance of the increase in Cx32 expression and alteration of Cx32 cellular localization in epithelial-to-mesenchymal transition (EMT) is not known. To determine if Cx32 overexpression and/or localization over one week would induce the EMT process, we first examined the cellular localization of Cx32 in MCF10A and MDA-MB-231 cells at different time points using Western blot and RT-PCR as well as immunostaining with confocal microscopy. Then, we correlated the changes of Cx32 expression and localization with EMT marker expression. We showed that Cx32 had altered cellular localization and Cx32 overexpression increased Slug levels while it reduced E-cadherin and Snail expression in MDA-MB-231 for 7 days. In contrast, E-cadherin and Vimentin were reduced in MCF10A-Cx32 cells compared with controls over 7 days, and the expression pattern for nuclear Cx32 and Zeb2 was following similar pattern in MCF10A cells. Our results suggest a previously unknown time-dependent relation between Cx32 and the regulation of the EMT process.Article The Effectiveness of Genetic Markers and the Role of Environmental Factors in Hip Dysplasia and Osteochondritis Dissecans of the Shoulder in German Shepherd, Labrador Retriever, and German Wirehaired Pointer (Deutsch Drahthaar) Dogs(Elsevier, 2025) Ardicli, Sena; Yigitgor, Pelin; Ozen, Dogukan; Babayev, Huseyn; Bozkurt, Berkay; Senturk, Nursen; Intas, Deniz SeyrekCanine Hip Dysplasia (CHD) is the most frequently diagnosed orthopedic condition in dogs. Similar to CHD, osteochondritis dissecans (OCD) of the shoulder is a developmental disorder in dogs that significantly impacts animal welfare. As polygenic genetic disorders, they exhibit a complex mode of inheritance. Although there are numerous clinical studies, there is insufficient information about the genetic basis of these disorders. Therefore, this study aimed to assess the relationship of the prognostic genetic test markers with CHD and OCD in German Shepherd, Labrador Retriever, and German Wirehaired Pointer dogs. We evaluated the efficiency of five SNP markers from the prognostic genetic test for CHD (the Dysgen test) based on available GWAS data in German Shepherd, Labrador Retriever, and German Wirehaired Pointer dogs. Radiographs were captured and assessed according to the official FCI scale for hip dysplasia. In German Wirehaired Pointers, shoulder X-ray evaluations were also performed. We used custom FRET-based primer probes in Real-time PCR and Sanger sequencing for genotyping and tested the evaluation using multiple logistic regression procedures. German shepherds emerged as the most vulnerable to CHD (P < 0.001). In the final logistic model, females are expected to have a 3.54 times higher likelihood of experiencing CHD compared to males (P < 0.05). SNP BICF2G630558239 demonstrated a notable association with CHD, indicating that the GG genotype poses a risk. This SNP is situated in the intronic region of the KIF26B gene, a member of the kinesin superfamily implicated in evolutionarily conserved roles in embryogenesis. We did not observe any association between shoulder OCD-related arthrosis and the SNPs studied. These results may contribute to understanding CHD by identifying genotypes associated with epidemiological risk, prompting the need to conduct more thorough investigations.Article Citation - WoS: 1Citation - Scopus: 1Experimental Study for Recovery of Heavy Metals From Contaminated Soil Using Arbuscular Mycorrhizal Fungi(Inderscience Enterprises Ltd, 2025) Budak, Bulent; Onay, Turgut T.; Goren, Aysegul Yagmur; Khalvati, AliSoil micro-organisms like arbuscular mycorrhizal fungi can provide beneficial symbiosis to their host plant and have been adopted to recover metal-polluted soils. This study investigates the removal of heavy metals from soil using phytoremediation in the presence of fungi. The results indicate that the sunflower plant illustrates the highest copper accumulation, with 18.55 mg/kg. In contrast, sunflower and sorghum controls (non-microorganisms) showed weak capability to transfer copper through plant biomass with 0.91 and 0.97 mg/kg, respectively. Both plants showed that phytoremediation can be a promising approach to providing sustainable solutions for soil heavy metal contamination in the presence of fungi.Article Gypsophila Eriocalyx Roots Inhibit Proliferation, Migration, and Tgf-Β Signaling in Melanoma Cells(Walter de Gruyter GmbH, 2025) Azbazdar, Yagmur; Ozhan, Gunes; Helvacioglu, SelinObjectives: Melanoma is a highly malignant and serious form of skin cancer. In addition to the standard treatments, complementary approaches, including phytotherapy, are also used to alleviate symptoms and improve patient well- being. This study aims to investigate the anticancer effects of Gypsophila eriocalyx (GE), an endemic species from Türkiye, on melanoma cells. We set out to determine the efficacy of GE in inhibiting melanoma cell proliferation, migration, and growth, and to explore its underlying mechanisms. Methods: We examined the impact of GE on the prolifera- tion of two melanoma cell lines, Malme-3M and SK-MEL-28, and assessed its developmental toxicity in zebrafish em- bryos. Next, we evaluated GE’s influence on colony forma- tion and wound healing in melanoma cells, as well as its ability to induce apoptosis and affect the TGF-β/Smad signaling pathway, by measuring pathway reporter activity and target gene expression. Results: GE inhibited cell proliferation in melanoma cell lines at concentrations 104 to 488 times lower than those required for normal non-malignant L929 fibroblast cells. In zebrafish embryos, GE demonstrated developmental toxicity only at concentrations above 50 μg/mL. GE treatment significantly impaired the colony formation and wound healing abilities of melanoma cells, indicating reduced pro- liferation and migration. Moreover, GE induced apoptosis in melanoma cells and inhibited the TGF-β/Smad signaling pathway, as evidenced by decreased pathway reporter activity and target gene expression. Conclusions: This study highlights the potential of GE as a novel therapeutic agent in melanoma treatment by demon- strating its ability to inhibit tumor growth and progressionArticle Citation - WoS: 1Citation - Scopus: 1Investigation of Flow and Heat Transfer Performance of Gyroid Structure as Porous Media(Turkish Soc Thermal Sciences Technology, 2024) Genc, Alper Mete; Karadeniz, Ziya HaktanThere are active and passive methods used to improve heat transfer. One of the passive methods is utilising porous media with high heat transfer surface area. Porous media are divided into two groups: regular and irregular structures. One of the regular structures is triply periodic minimal surfaces (TPMS), which have been studied quite frequently recently. In this study, heat transfer and flow analysis of a Gyroid geometry, one of the most used TPMS in the literature, is investigated numerically considering the conjugate heat transfer conditions. A single porosity is considered (epsilon = 0.6), and aluminium, ceramic and PLA are selected for the heat exchanger material to examine the temperature change in the heat exchanger. To understand the different flow characteristics, Reynolds numbers are assumed to be 19.12, 95.61 and 172.09. The fluid inlet temperature is assumed to be constant at 298.15 K, and the initial temperature of the heat exchanger is assumed to be constant at 278.15 K to be consistent with the regenerative heat recovery temperature difference in ventilation standards. Nusselt numbers under different operating conditions are compared, and it is the ceramic material with low thermal diffusivity is at the highest level despite its low thermal conductivity. At the highest Reynolds number, it provided approximately 6% better heat transfer than the aluminium heat exchanger.