WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Influence of Fluorine on Structural and Electrical Properties of VO2 Thin Films Deposited by Magnetron Sputtering(Elsevier Ltd, 2025) Akyurek, Bora; Cantas, Ayten; Demirhan, Yasemin; Ozyuzer, Lutfi; Aygun, GulnurThis study investigates whether fluorine-based thermal gel used during electrical measurements of vanadium oxide (VO2) films influences the structural, morphological, or compositional integrity of the films. High-quality VO2 films with a resistance ratio change of about 10(4) for metal-insulator transition were deposited by magnetron sputtering. During electrical characterization, VO2 film was heated from room temperature to similar to 370 K with a fluorine-based thermal gel usage to achieve better heat contact between the film and substrate holder. Structural and chemical properties were assessed through XRD, Raman, XPS, SEM, and energy dispersive spectroscopy imaging. XRD revealed diffraction peaks consistent with monoclinic VO2 confirming that the crystal lattice remains the same although fluorine based thermal gel was used. Raman spectra exhibited vibrational modes indicating that the phonon structure of VO2 was preserved despite fluorine gel usage. XPS results showed only a minor F 1s signal (2.8%) limited only to the film surface. SEM and EDS analyses further confirmed that surface morphology and elemental composition remained belonging to VO2 film. These findings demonstrate that the usage of fluorine-based thermal gel results in only a minimal surface interaction, thereby preserving intrinsic material properties of VO2 and supporting a potential usage for future device fabrication applications.Article Citation - Scopus: 1Assessing the Density of Wood in Heritage Buildings’ Elements Through Expedited Semi-Destructive Techniques(Multidisciplinary Digital Publishing Institute (MDPI), 2025) Henriques, Dulce F.; Sen, Ali Umut; Gomes, Maria da GloriaFeatured Application The research presented and justified in this text aims to provide agents involved in the conservation and refurbishment of old timber elements in buildings with a correlation table for interpreting the readings obtained with penetration resistance testing equipment.Abstract Historically, wood has been among the main materials used in heritage buildings. However, the species and mechanical properties of these elements are often unknown. This uncertainty complicates safety assessment calculations, aggravated by the natural variability of the wood properties. The aim of this work is to assess the density of wooden elements in service using semi-destructive techniques that retain the integrity of structural elements. This research had two phases. First, penetration resistance tests were carried out on laboratory scale on Pinus sylvestris L. wood samples taken from 18th, 19th, and 20th century heritage buildings in Lisbon, Portugal. Later, a field study was carried out on wooden elements from the same buildings, involving needle penetration, core drilling, and moisture content determination tests. The laboratory test results showed a strong correlation between the needle penetration depth and wood density, with an R2 value of 0.76. The results of the field study indicated that the density estimated by the needle penetration test correlated effectively with the measured density of extracted cores after moisture correction, with an R2 of 0.99. In conclusion, the experimental results confirm that penetration resistance and moisture tests are reliable and practical for estimating wood density under in-service conditions.Article Tc-99m Erythromycin Lactobionate Inhalation Scintigraphy in Parenchymal Lung Diseases(Elsevier Science inc, 1999) Durak, H; Aktogu, S; Degirmenci, B; Sayit, E; Ertay, T; Dereli, SWe have investigated Technetium 99m erythromycin lactobionate (Tc 99m EL) clearance from the lungs after inhalation, in the presence of an alveolitis. Eighteen patients (6 sarcoidosis, 7 idiopathic fibrosis, and 5 miliary tuberculosis) were imaged after the patients inhaled 1,110 MBq of Tc 99m EL. Clearance half time for the first 45 min, for 24 h, and retention at 24 h correlated with percentage of lymphocytes in bronchoalveolar lavage fluid (BAL) (r =.729, r =.883, and r =.826, respectively). There was a positive correlation between peripheral penetration (PP) and forced expiratory volume in 1 s (FEV1) (r =.806) and forced vital capacity (FVC) (r =.781). Retention was more marked in sarcoidosis compared with tuberculosis (0.025 < p less than or equal to 0.05). Radioaerosol lung imaging may reflect the pulmonary function impairment in parenchymal lung diseases. Retention of Tc 99m EL may be related to number of BAL cells or presence of a lymphocytic alveolitis. Long residency time of Tc 99m EL in the lungs implies that erythromycin can also be administered by inhalation for therapeutic purposes. NUCL MED BIOL 26;6:695-698, 1999. (C) 1999 Elsevier Science Inc. All rights reserved.Article Citation - WoS: 2Citation - Scopus: 2Experimental Integration of Stone Topologies To the Simplified Micro-Modeling for the Seismic Response of Masonry Walls: a Novel Insight(Springer Heidelberg, 2025) Demir, UgurThis study aims to explore the impact of stone typologies on the in-plane seismic behavior of stone masonry buildings. The present study aims to quantify the strength and deformability parameters such as lateral load capacity, ductility, energy dissipation capacity and stiffness degradation of frequently used sandstone and limestone masonry, which will intentionally contribute to the core body of knowledge on their original structural design, seismic safety evaluation and intervention design. The innovative aspect of this research lies in the holistic methodology that integrates field surveys to classify local stone masonry units, experimental characterization of the chemical and mechanical properties of these units to capture variability, and finite element modeling of the in-plane cyclic behavior of stone masonry walls using experimental data. A novel simplified micro-modeling approach is implemented within a standard finite element software, eliminating the need for user-defined subroutines. This approach significantly reduces computational efforts compared to conventional methods, making it particularly suitable for analyzing large-scale stone masonry structures. The study investigates the impact of chemical composition (sandstone or limestone), applied axial stress (0.25 MPa, 0.50 MPa, or 1 MPa), and wall aspect ratios (height-to-length ratios of 1.0 or 1.5) on wall performance. The modeling approach is validated against experimental results from the literature, demonstrating good agreement. Finally, the study assesses wall performance in terms of deformation limits in current seismic codes. The findings provide critical insights for developing innovative design strategies to enhance the structural integrity of stone masonry walls and improve the seismic assessment of existing structures.Article Citation - WoS: 1Citation - Scopus: 1Exploring Sainfoin (Onobrychis Viciifolia) Seed Flour as a Sustainable Plant-Based Food: Germination-Induced Changes in Nutritional Quality, Anti-Nutritional Factors, Phenolic Content, Bioaccessibility, and in Vitro Toxicity(Wiley, 2025) Kaya, Havva Polat; Gungor, Sevde Nur; Tuncel, Nese Yilmaz; Sakarya, Fatma Betul; Andac, Ali Emre; Ozkan, Gulay; Tuncel, Necati BarisBackground and Objectives: Sainfoin is a drought-resistant perennial plant mainly used as animal feed, but its seeds remain underexplored as a food source. This study investigates the effects of germination on the nutritional quality of dehulled sainfoin seeds. Specifically, it examines changes in proximate composition, antinutrients (hydrocyanic acid, tannins, phytates, saponins, and trypsin inhibitors), in vitro starch digestibility, phenolic content, antioxidant capacity, and cytotoxicity. Findings: Germination significantly increased crude protein (up to 45%) and fat (up to 10%) contents. Despite low total starch (similar to 7%), 45-h germination reduced total digestible starch while increasing rapidly digestible starch. Antinutrient levels decreased significantly-tannins by 57%, phytates by 30%, saponins by 40%, and trypsin inhibitors by 29%-with the exception of hydrocyanic acid. Although total phenolics, flavonoids, and antioxidant capacity declined, their bioaccessibility improved. No cytotoxic effects were observed in either raw or germinated seeds. Conclusions: Germination improved the nutritional profile of sainfoin seeds by increasing protein and fat contents, while reducing most antinutrients. Despite a decrease in antioxidant levels, their bioaccessibility was enhanched. The absence of cytotoxic effects further supports the potential application of germinated sainfoin seeds in human nutrition. Significance and Novelty: Although few studies have focused on the green form of sainfoin, which is commonly used as livestock feed, this study reveals that sainfoin seeds offer substantial potential as food, with germination emerging as a simple and effective approach to improving their nutritional properties.Article Nanostructured Ox-MWCNT-Ppy-Au Electrochemical Sensor for Ultralow Detection of Retrorsine and Evaluation of Its Cytotoxic Effects on Liver Cells(Taylor & Francis Ltd, 2025) Akturk, Ezgi Zekiye; Njjar, Muath; Ata, Melek Tunc; Kaya, Ahmet; Akdogan, Abdullah; Onac, CananThis study presents the development of a novel retrorsine (RTS)-imprinted sensor utilizing oxidized multi-walled carbon nanotubes (Ox-MWCNTs), polypyrrole (PPy), and gold nanoparticles (AuNPs), employing square wave voltammetry for the sensitive and selective detection of RTS which causes oxidative-stress and DNA damage. The fabricated Ox-MWCNT-PPy-AuNP sensor demonstrated a surface-area of (0.218 cm2) is 4.25 times larger than a bare glassy carbon electrode, with a low charge transfer resistance (10.9 Omega), enhancing electron transfer kinetics. The sensor showed excellent sensitivity in detecting retrorsine, with a limit of detection of 0.035 nM in synthetic matrices and -0.030 nM in HepaRG cell culture medium. Toxicity assays in HepaRG cells revealed dose-dependent oxidative-stress, with glutathione levels decreasing from 23.08 +/- 0.21 mu mol/109 to 21.21 +/- 0.02 mu mol/109 at 35 mu M retrorsine. Concurrently, GSSG levels increased from 1.32 +/- 0.26 mu mol/109 to 2.22 +/- 0.02 mu mol/109. DNA-damage assessed via comet assay, showed significant increases in tail-moment (2.53 mu m) and tail-migration (16.13 mu m). Oxidative DNA-damage, indicated by 8-OHdG levels, increased significantly from 0.29 +/- 0.02 ng.mL- (control) to 0.47 +/- 0.07 ng.mL- at 35 mu M retrorsine. These findings demonstrate the sensor's effectiveness for retrorsine detection and its applicability in toxicological studies. The integration of nanomaterial engineering and molecular imprinting provides a highly sensitive, selective, and eco-friendly solution for monitoring toxic agents and assessing their biological impacts.Article In-Depth Analysis of Drought Trend in Semiarid Saïs Plateau and Middle Atlas Region in Morocco(Springer int Publ Ag, 2025) Qadem, Zohair; Tayfur, Gokmen; Kankal, MuratThis study explores the spatiotemporal properties of droughts and their evolution in the semiarid Sa & iuml;s Plateau and the Middle Atlas regions in Morocco. The methodology includes the analysis of 36 years of precipitation data recorded at 16 meteorological stations, the use of the standardized precipitation index (SPI) at different temporal scales of short term (1 and 3 months), medium term (6 months), and long term (12 and 24 months) to capture historical droughts, and the application of the Mann-Kendall test to assess the drought trends. The wet and dry periods in the Sa & iuml;s Plateau and Middle Atlas regions are almost evenly distributed, with 65% in the "near-normal" condition. The "extremely dry" period, with a value of 1%, was lower than the "extremely humid" period (1.65%). There is no topographically and climatically significant difference between the Sa & iuml;s Plateau and the Middle Atlas in terms of droughts, which are found to decrease over time in both regions. The results of Mann-Kendall test reveal that the short-term trends are generally positive, except at the Boulemane station (- 0.06 for SPI-1, - 0.13 for SPI-3). The long-term precipitation increases in the Middle Atlas region, particularly at the Ait Khabach (0.33 for SPI-24) and the Imouzzer (0.36 for SPI-24) stations. On the Sa & iuml;s Plateau, the trends are positive at the stations of Fez City (0.16 for SPI-24) and Dar Elarsa (0.27 for SPI-24). Significant trends are more pronounced at longer time scales.Article Citation - WoS: 1Citation - Scopus: 1Understanding the Role of a Specific Microenvironment in Personal Exposure To Semi-Volatile Organic Compounds Using Silicone Wristbands(Royal Soc Chemistry, 2025) Akmermer, Zulfikar; Demirtepe, HaleAssessment of personal exposure to semi-volatile organic compounds was facilitated using silicone wristbands (SWBs), an easy-to-use sampler that reflects total inhalation and dermal exposure from all the microenvironments and the activities in which the user was involved. Hence, SWBs help understand exposure from various routes, activities, and microenvironments. Offices are critical microenvironments where workers spend one-third of their daily time on weekdays; hence exposure from offices should be more extensively studied. This study aimed to investigate the personal exposure of university personnel and elaborate on the contribution of the exposure due to the office air to their overall exposure using SWBs. One SWB was worn by the participant, and another was hung in their office. After seven days of sampling on the wrist, exposure to polycyclic aromatic hydrocarbons (PAHs) was found to be related to combustion activities at home or from open fire, whereas exposure to organophosphate esters and phthalates was suggested to originate from building materials, such as flooring materials and paints, and consumer products, e.g. mattresses and furniture. PAHs in the participants' offices were influenced by the transport of outdoor air and phthalates from the ceiling material. Then, we estimated the equivalent air concentrations using the SWBs sampled from the offices and previously developed sampling rates and partition coefficients. The estimated office air exposure contributions to total inhalation and dermal exposure were 83%, 51%, and 39% for fluorene, tri(n-butyl) phosphate, and tris(2-chloro isopropyl) phosphate, respectively. These findings were consistent with the statistical analysis of personal data. To conclude, this study highlighted the importance of specific microenvironments in our exposure to particular SVOCs, offering strategies for indoor air quality management and human health risk assessment.Article Citation - WoS: 1Citation - Scopus: 1A Pragmatic Grouping Model for Bone-Only De Novo Metastatic Breast Cancer (MetS Protocol MF22-03)(MDPI, 2025) Goktepe, Berk; Demirors, Berkay; Senol, Kazim; Ozbas, Serdar; Sezgin, Efe; Lucci, Anthony; Soran, AtillaDe novo metastatic breast cancer (dnMBC) accounts for 3-10% of newly diagnosed cases, with 20-40% presenting as a bone-only metastatic disease, which can achieve survival outcomes exceeding 10 years with multimodal therapy. However, the role of multimodal therapy remains controversial in the guidelines. Objective: This study aims to identify dnBOMBC subgroups to develop a pragmatic staging system for guiding locoregional therapy decisions. Materials and Methods: Data from the MF07-01 phase III randomized trial (2021, median follow-up time (mFT): 40 months (range 1-131)) and the BOMET prospective multi-institutional registry trial (2021, mFT: 34 months (range 25-45)) were combined for analysis, including only patients who presented with bone-only metastases. Exclusion criteria were patients under 18 and those with a history of prior cancer or cancer metastases. Patients with missing data and positive surgical margins were excluded. Out of 770 patients, 589 were included. Survival analyses were first conducted according to molecular subgroups, after which patients were further stratified by hormone receptor status, human epidermal human epidermal growth factor receptor 2 (HER2) status, tumor grade, and clinical T (cT) stage. Group A (GrA) included hormone receptor (HR)-positive, low- or intermediate-grade tumors at any cT; HR-positive, high-grade tumors with cT0-3; or any HER2-positive tumors. Group B (GrB) included HR-positive, high-grade tumors with cT4 disease or any triple-negative (TN) tumors. Results: The hazard of death (HoD) was 43% lower in GrA than in GrB. Median OS was 65 months (39-104) for GrA patients and 44 months (28-72) for GrB patients (HR 0.57, 95% CI 0.41-0.78, p = 0.0003). Primary tumor surgery (PTS) significantly improved OS in GrA patients, regardless of the number of metastases (solitary: HR, 0.375, 95% CI 0.259-0.543, p < 0.001; multiple: HR 0.435, 95% CI 0.334-0.615, p < 0.001). Conversely, GrB patients did not experience a significant benefit from PTS. Conclusions: This study demonstrates that GrA patients have better OS than GrB patients, and PTS reduces the HoD in GrA patients compared to systemic therapy alone. These findings support using a modified staging system in dnBOBMC to identify patients who may benefit from multimodal therapy including PTS.Article Functional Manipulation of Nonspherical Nanoparticles With Cascaded Reconfigurable Modules(Elsevier, 2025) Arslanyurek, Seyma; Dinleyici, Mehmet SalihSelective nanoparticle sorting is essential for applications requiring monodisperse distributions, yet conventional methods lack adaptability for shape-based separation. This study introduces a reconfigurable optical manipulation technique that dynamically sorts spherical and non-spherical nanoparticles using cascaded modules based on evanescent fields. Optical forces were calculated using the Discrete Dipole Approximation (DDA) method, enabling the modeling of various particle shapes and accurately capturing rotational and translational movements. Two cascaded strategies are proposed: the first approach enables fluid-assisted filtration by selectively trapping spherical particles while allowing non-spherical ones to be carried away by the flow. The second strategy first induces the rotational alignment of particles and then employs a trapping mechanism that selectively retains specific geometries, enabling the separation of spherical and non-spherical nanoparticles. Unlike traditional approaches, this method enables high-precision, shape-selective separation without external flow modifications. The results demonstrate unprecedented control and efficiency in nanoparticle sorting, offering a scalable, high-throughput solution for microfluidic and optofluidic applications.