Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Identification of Turkish Extra Virgin Olive Oils Produced in Different Regions With Volatile Compounds(Innovhub SSI-Area SSOG, 2025) Sevim, Didar; Koseoglu, Oya; Ertan, Hasan; Ozdemir, Durmun; Ulan, MehmetThis study aims to characterize the composition of the volatile compounds in Turkish extra virgin olive oils (EVOOs) produced from three cultivars-Ayvalik, Gemlik, and Memecik-harvested in the South Marmara, South Aegean, and North Aegean regions during the 2014/15 and 2015/16 crop seasons. A total of 135 EVOO samples were obtained using industrial-scale 2-phase and 3-phase extraction systems. These samples were then analyzed using solid-phase microextraction (SPME) coupled with gas chromatography (GC). Among the twelve volatiles identified, trans-2-hexen-1-ol and cis-2-penten-1-ol exhibited the highest levels of abundance across all samples and seasons. Subsequently, 1-penten-3-one, hexanal, and cis-3-hexenyl acetate were identified, and it was determined that these contribute to the green and fruity sensory profile of high-quality olive oil. Two- and three-factor analyses of variance (ANOVA) revealed that volatile concentrations were significantly influenced by variety, harvest season, and extraction system. It is significant that 1-penten-3-one was found to be significantly influenced by both season and variety (p < 0.05), while 1-penten-3-ol exhibited a multifactorial dependency, with significant two-way interactions (season x variety, season x system, variety x system). Furthermore, PLS-DA-based classification successfully distinguished samples according to olive variety, indicating that volatile profiles could serve as reliable markers for authenticity and geographic origin. These findings underscore the potential of using volatile compounds as quality indicators and for geographic labelling in the olive oil industry.Article Geothermal Resources of Azerbaijan: A Comprehensive GIS-Based Remapping and Temperature Assessment Review(State Oil Company of Azerbaijan Republic, Oil Gas Scientific Research Project Institute, 2025) Isgandarov, S. M.; Uzelli, T. T.; Mukhtarov, A. N.; Baba, A. S.Azerbaijan has considerable geothermal energy potential. The resources are concentrated in regions such as the Absheron Peninsula, the Greater and Lesser Caucasus, the Kur Basin, and the Pre-Caspian-Guba region. Although the country does not have active volcanoes and geysers, geothermal energy can be extracted from deep wells, abandoned hydrocarbon fields, and natural hot springs. This study analyzes and maps Azerbaijan's geothermal resources using a Geographic Information System (GIS) to assess their potential for power generation and direct use. The main results show that wells such as Jarly-3 field thermal fluids with temperatures of up to 96 degrees C. Other promising sites include Daridagh in Nakhchivan and the Shikh field in Absheron, where geothermal water with a temperature of 68 degrees C. GIS-based interpolation techniques, including Kriging and Empirical Bayesian Kriging were applied to model the subsurface temperature distributions and identify regions with the highest geothermal potential. The study analyzed data from over 500 hot springs and geothermal wells to determine temperature variations at different depths. The results indicate that Azerbaijan's geothermal resources could support applications ranging from electricity generation to heating, agriculture, and industrial processes. Developing these resources could diversify Azerbaijan's energy sector and reduce dependence on fossil fuels. This study highlights the need for further exploration, improved drilling technologies, and investment in geothermal infrastructure to unlock the full potential of Azerbaijan's geothermal reserves.Article Seismic Risk Prioritization of Stone Masonry Building Stock in Urla Peninsula Based on Rapid Assessment Techniques(Turkish Chamber of Civil Engineers, 2026) Karavin, Y.S.; Akdag, N.; Demir, U.This study aims to investigate seismic risk of stone masonry buildings in the Urla Peninsula, a region of historical and architectural significance within İzmir, Türkiye. A total of 100 stone masonry buildings were surveyed and documented with a focus on their architectural characteristics, including construction techniques, material types, structural configurations, and age. Data on the properties of all surveyed buildings are provided in an open-access database. Based on the survey, multiple rapid seismic performance assessment methods were applied to evaluate the vulnerability of these structures. These included: i) FEMA P-154 Rapid Visual Screening, ii) Provisions for the Seismic Risk Evaluation of Existing Buildings under Urban Renewal Law (RBTE-2019), iii) Seismic Vulnerability Index for Vernacular Architecture (SVIVA), and iv) the Masonry Quality Index (MQI). The comparative use of different methods is intended to investigate the relative influence of parameters shaping the seismic performance of the masonry building stock rather than to align their scores. The outcomes of this research are expected to contribute to the current risk mitigation efforts for stone masonry buildings in İzmir, thereby supporting regional seismic resilience planning. © 2026, Turkish Chamber of Civil Engineers. All rights reserved.Article Dissecting the Metabolic Landscape of Breast Cancer Subtypes via Elastic Net Modeling and Examining Its Immune Correlates(Walter de Gruyter GmbH, 2026) Kus, M.E.; Ekiz, H.A.Objectives: Breast cancer is a heterogeneous disease, and the estrogen receptor (ER) status is a key factor in disease classification and treatment planning. While metabolomic profiling has revealed subtype-specific differences, cross-study comparisons have been limited, posing challenges for data extrapolation. This study aims to investigate metabolites that differentiate ER-positive and ER-negative tumors via integrative analyses of multi-omics data. Methods: We jointly analyzed two untargeted metabolomics datasets via elastic net modeling using consistent analysis pipelines tuned for low sample sizes, namely multiple bootstrapping and stability selection. Significant metabolite predictors from two studies were cross-examined to reveal distinctions and commonalities. We also performed differential gene expression analysis using RNA sequencing data from matching samples to link metabolic patterns with transcriptomic signatures and intratumoral immune cell signatures. Results: This study identified unique metabolite signatures in distinct datasets and a limited overlap of discriminating metabolites that can be broadly generalizable for subtyping. Nevertheless, several glycolysis and fatty acid metabolism intermediates exhibited variation depending on the tumor ER status. Consistently, genes related to fatty acid metabolism and glycolysis were enriched in ER-positive and ER-negative tumors respectively. Furthermore, we used multiple immune cell deconvolution algorithms to correlate various immune cell types with the metabolite levels within the tumor microenvironment. Conclusions: Together, these findings highlight the metabolic and immunological diversity of breast cancer and establish a reproducible machine-learning framework for integrating multi-omics data to interrogate tumor complexity. © 2025 the author(s), published by De Gruyter, Berlin/Boston.Article Determining Area Affected by Corona in Lung Computed Tomography Images by Three-Phase Level Set and Shearlet Transform(Wolters Kluwer Medknow Publications, 2025) Aghazadeh, Nasser; Noras, Parisa; Moghaddasighamchi, SevdaBackground:The COVID-19 pandemic has created a critical global situation, causing widespread challenges and numerous fatalities due to severe respiratory complications. Since lung involvement is a key factor in COVID-19 diagnosis and treatment, accurate identification of infected regions in lung images is essential.Methods:We propose a multiphase segmentation method based on the level set framework to determine lunginvolved areas. The shearlet transform, a high-precision directional multiresolution transform, is employed to guide the gradient flow in the level set formulation. Additionally, the phase stretch transform (PST) is applied to enhance the contrast between infected and healthy regions, improving convergence speed during segmentation.Results:The proposed algorithm was tested on 500 lung images. The method accurately identified infected areas, enabling precise calculation of the percentage of lung involvement. The use of the shearlet transform also allowed clear delineation of ground-glass opacity boundaries.Conclusion:The proposed multiphase level set method, enhanced with shearlet and phase stretch transforms, effectively segments COVID-19-infected lung regions. This approach improves segmentation accuracy and computational efficiency, offering a reliable tool for quantitative lung involvement assessment.Article Improving Doppler Radar Performance through Optically-Reconfigurable Unequal Power Division with Semi-Analytical Approach(Taylor & Francis Ltd, 2025) Karatay, Anil; Atac, Enes; Dinleyici, Mehmet Salih; Yaman, FatihThe improvement of the signal-to-noise ratio (SNR) of Doppler radar systems, enabling the detection of targets at greater ranges even with limited power, has been a longstanding focus of research. However, while key limitations such as low target reflectivity and environmental interference are often addressed, the impact of efficient use of the input power remains an overlooked, yet crucial factor in overall sensitivity. Additionally, the power allocation needs to be examined from an analytical perspective for further enhancement. In this study, we present a novel measurement approach, utilizing both semi-analytical analysis and experimental methods, to improve the performance of a dual-antenna CW Doppler radar through the use of an optically reconfigurable unequal microwave power divider which provides well-directed power utilization. Comprehensive grid searches, supported by an analytical approach and considering various loss and noise scenarios, demonstrate the capability of the proposed reconfiguration method. In the Doppler radar experiments where the pendulum and servo motor were used as targets, an SNR increase of 3.04 and 2.11 dB in the radar signal was observed with the proposed method, respectively. This noticeable improvement in the SNR of the time-frequency plots indicates an enhancement in the measurement performance. The unequal power allocation enabled continuous detection of target motion with minimal signal loss, lowering the minimum detectable power level by more than 2 dB compared to the equal power division case. The experimental results show that integrating an optically reconfigurable microwave power divider into the Doppler radar system increases precision in velocity measurements.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 Citation - WoS: 1Citation - Scopus: 1Two Key Substitutions in the Chromophore Environment of mKate2 Produce an Enhanced FusionRed-Like Red Fluorescent Protein(Russian Federation Agency Science & innovation, 2025) Ruchkin, D. A.; Gavrikov, A. S.; Kolesov, D., V; Gorokhovatsky, A. Yu.; Chepurnykh, T., V; Mishin, A. S.; Bogdanov, A. M.Red fluorescent proteins (RFPs) are often probes of choice for living tissue microscopy and whole-body imaging. When choosing a specific RFP variant, the priority may be given to the fluorescence brightness, maturation rate, monomericity, excitation/emission wavelengths, and low toxicity, which are rarely combined in an optimal way in a single protein. If additional requirements such as prolonged fluorescence lifetime and/or blinking ability are applied, the available repertoire of probes could dramatically narrow. Since the entire diversity of conventional single-component RFPs belongs to just a few phylogenetic lines (DsRed-, eqFP578-and eqFP611-derived being the major ones), it is not unexpected that their advantageous properties are split between close homologs. In such cases, a systematic mutagenetic analysis focusing on variant-specific amino acid residues can shed light on the origins of the distinctness between related RFPs and may aid in consolidating their strengths in new RFP variants. For instance, the protein FusionRed, despite being efficient in fluorescence labeling thanks to its good monomericity and low cytotoxicity, has undergone considerable loss in fluorescence brightness/lifetime compared to the parental mKate2. In this contribution, we describe a fast-maturing monomeric RFP designed semi-rationally based on the mKate2 and FusionRed templates that outperforms both its parents in terms of molecular brightness, has extended fluorescence lifetime, and displays a spontaneous blinking pattern that is promising for nanoscopy use.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.