WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7150

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  • Article
    Importance of Zoning for Vertical Circulation Planning of Densely Populated Buildings: A Simulation Based Approach for Elevator Traffic Analyses
    (Gazi Univ, 2025) Deligoz, Dostcan; Harputlugil, Timucin
    Elevator systems are essential in multi-story buildings, affecting circulation, travel time, and user comfort. Traditional design methods, based on mathematical calculations, provide initial estimates of elevator numbers and capacities by considering basic operational criteria. However, these methods cannot fully capture dynamic passenger flows and temporal variations in demand. Dynamic simulation-based elevator traffic analysis, on the other hand, allows for more comprehensive evaluation of elevator operations and enables testing of alternative zoning scenarios. In this study, a dynamic simulation-based analysis is applied as a case study for a hospital outpatient building. Different zoning strategies are implemented for elevator groups to evaluate their effect on system performance. Performance criteria, including Average Waiting Time (AWT), Average Time To Destination (ATTD), and Interval (INT), are assessed across different zoning scenarios and compared with values commonly reported in the literature. The results highlight the potential of zoning to improve elevator performance, including passenger handling, waiting times, and travel efficiency. Especially in buildings where physical modifications are difficult, the combination of simulation-based analysis and carefully designed zoning strategies can reveal the potential for enhancing operational performance and optimizing elevator efficiency within existing physical constraints.
  • Article
    A First Process-Oriented Characterization of Eriolobus Trilobatus (Labill. Ex Poiret) Bark From Turkey: Chemical, Morphological and Energy Properties
    (MDPI, 2025) Sen, Umut; Yucedag, Cengiz; Balci, Busra; Arici, Sefik; Kocar, Gunnur; Sat, Beyza; Pereira, Helena
    For the first time, Eriolobus trilobatus bark from Turkey has been characterized in terms of its chemical, extractive, fuel, and ash characteristics using SEM-EDS, wet chemical analysis, phenolic analysis, FT-IR, TGA, XRF, XRD, BET surface area measurement, proximate analysis, and ash fusion temperature (AFT) determination. The results showed that the bark contains 13% ash, dominated by calcium oxalate, and 15% extractives, largely composed of polar phenolic compounds with moderate radical-scavenging potential. Thermal decomposition of bark proceeds in four distinct stages, associated with the sequential degradation of extractives/hemicelluloses, cellulose, lignin/suberin, and inorganic fractions. The higher calorific value of 14.9 MJ/kg indicates moderate fuel quality compared with conventional woody biomass. Ash is mesoporous with a CaO-rich structure highly suitable for catalytic applications in biodiesel production and biomass gasification. Ash fusion analysis revealed a high flow temperature (1452 degrees C), indicating a very low slagging risk during thermochemical conversion. Overall, E. trilobatus bark is a promising material for value-added biorefinery pathways, enabling processes for the production of biochars, CaO-based catalysts, phenolic extracts, and sustainable energy. The valorization of E. trilobatus bark not only enhances the economic potential of forestry residues but also provides environmental co-benefits through carbon soil amendment and landscape applications.
  • Article
    Semi-Synthetic Sapogenin Derivatives Inhibit Inflammation-Induced Tumorigenic Signaling Alterations in Prostate Carcinogenesis
    (Elsevier Science Inc, 2026) Debelec-Butuner, Bilge; Ozturk, Mert Burak; Tag, Ozgur; Akgun, Ismail Hakki; Bedir, Erdal
    Prostatic inflammation plays a pivotal role in prostate cancer development and progression via altering key cellular mechanisms, including proliferation, metastasis, and angiogenesis. Therefore, the use of antiinflammatory drugs could provide a valid contribution to PCa prevention and treatment. In our research, we explored semi-synthetic derivatives of cycloastragenol (CA) and astragenol (AG) to assess their potential to inhibit inflammation-mediated tumorigenic signaling. Building on our previous findings, which demonstrated their inhibitory activity on NFxB, we discovered that these molecules also suppress inflammation-induced cell proliferation and migration through distinct mechanisms. They effectively alleviated inflammation by reducing levels of ROS, NO, and VEGF expression. Furthermore, these molecules partially restored the expression of AR and the tumor suppressor NKX3.1, both of which are critical in prostate tumorigenesis within an inflammatory microenvironment. They also reversed inflammation-induced activation of Akt and (3-catenin signaling, suggesting their potential to inhibit inflammation-related prostate tumorigenesis. Our study further demonstrated that these molecules exhibited dose-dependent effects on inducing cell cycle arrest and apoptosis, as evidenced by increased p21 and decreased BCL-2 protein levels, leading to activated cell death and suppressed cellular migration. In conclusion, these semi-synthetic sapogenol derivatives demonstrate significant potential as antiinflammatory and anticancer agents, offering a promising approach for targeting prostatic inflammation and inflammation-driven prostate carcinogenesis.
  • Article
    Chemical Composition and Reactivity of Quercus Pubescens Bark and Bark Fractions for Thermochemical Biorefinery Applications
    (MDPI, 2025) Sen, Umut; Balci, Busra; Arici, Sefik; Sat, Beyza; Miranda, Isabel; Pereira, Helena
    Advancing circular bioeconomy in thermochemical biorefineries requires species-specific data that link biomass composition and thermochemical performance. Here, we provide the first integrated thermochemical dataset for Quercus pubescens bark combining FT-IR, XRD, XRF, TGA, and measured ash fusion temperatures (AFT). The results reveal that bark is enriched in phenolic extractives (21.2%) and inorganics (15%), with calcium oxalate monohydrate (COM) dominating the inorganic fraction, as confirmed by FT-IR and XRD. Thermal decomposition occurs between 150 degrees C and 690 degrees C. Pyrolysis follows diffusion-controlled kinetics, with apparent activation energies for bark and its fractions ranging between 70 and 103 kJ mol-1. Extraction increases the activation energy of bark. The ash exhibits a high AFT (softening: 1421 degrees C, flow: 1467 degrees C), placing this feedstock within the low-slagging, moderate-fouling range compared to other lignocellulosics. The observed COM-to-CaCO3/CaO transformation upon heating contributes to the elevated AFT. Reactivity analyses of bark fractions support thermochemical biorefinery routing of fractions: extracted bark (EB) and desuberinised bark (DB) are highly reactive and well-suited to combustion/gasification, whereas raw bark (B) and Klason lignin (KL) exhibit higher thermal stability and yield more persistent char, favoring slow pyrolysis for biochar production. Such routing strategies optimize energy recovery and also enable co-products with environmental co-benefits.
  • Article
    One-Pot, Light-Induced, Liquid Crystal-Templated Synthesis of Nanoporous Silver Films at Room Temperature
    (TÜBİTAK, 2025) Mert-Balci, F.
    Nanoporous silver (NPS) films, characterized by a 3-dimensional bicontinuous structure of interconnected nanopores and ligaments, have found widespread use in spectroscopy, plasmonics, solar cells, catalysis, and chemical sensing. Traditionally, NPS films are fabricated via chemical dealloying, where a less noble metal (e.g., Cu or Al) is selectively removed through harsh chemical etching. However, residual traces of these metals can adversely affect the performance of NPS thin films in applications such as plasmonics and catalysis. This paper reports a one-pot, liquid crystal-templated method for synthesizing ultrapure NPS thin films at room temperature for the first time. The process begins with the preparation of an LLC composed of a nonionic surfactant and AgNO<inf>3</inf> that is then coated onto solid substrates. Exposure of the LLC film to ultraviolet light facilitates the in situ synthesis of Ag nanoparticles within the liquid crystal film. Subsequent solvent washing removes the surfactant molecules and any unreacted metal ions, yielding NPS films comprised of densely packed Ag nanoparticles on glass substrates. The resulting NPS films feature a 3-dimensional structure with uniformly distributed, interconnected nanopores. Synthesized under ambient conditions and scalable over large areas, these ultrapure NPS films present a highly promising platform for advanced applications in catalysis, spectroscopy, plasmonics, and biosensing. © TÜBİTAK.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Synthesis of Pristine Chitosan Foams with Enhanced Pore Structure, Surface Area, and Mechanical Strength for Tissue Engineering Applications
    (Iop Publishing Ltd, 2025) Polat, M.; Cropper, Chelsea; Ozdamar, A. B.; Polat, H.
    With its excellent biocompatibility, biodegradability, and antimicrobial activity, chitosan is a promising scaffold material for hard-tissue engineering. Yet, pristine chitosan foams typically lack the strength and porosity required for such use. Here we present a simple emulsion-templating approach to fabricate pristine chitosan foams with optimized strength and porosity. Sodium dodecyl sulfate (SDS), a widely used biocompatible anionic surfactant, was employed at trace levels to aid polymerization. The foams display a dual-scale pore morphology. Cavities of 150-300 mu m are separated by around 50 mu m thick chitosan walls containing large interconnecting openings. The walls are further populated with meso- and macropores of 50-500 nm. This architecture should support cell attachment and growth, facilitate proliferation, and enhance nutrient transport and metabolic exchange. The structure yields high surface area (up to 10 m2 g-1). Mechanically, the thick-walled cavities impart both elastic recovery and high compressive resistance (255 kPa at 40% strain from foams polymerized with 4% chitosan). A preliminary drug-release study using vancomycin confirmed excellent loading and sustained release.
  • Article
    Subtype-Specific Divergent Roles of Calpain-1 and Calpain-2 in Basal a Triple-Negative Breast Cancer
    (BMC, 2025) Uner, Goklem; Oztarhan, Gokhan; Kirmizibayrak, Petek Ballar
    BackgroundCAPN-1 and CAPN-2, two ubiquitously expressed calpains, have been implicated in cancer progression, but their distinct roles in breast cancer remain poorly defined. This study aims to define the opposing roles of CAPN-1 and CAPN-2 in breast cancer progression, with a focus on their regulatory impact on cell proliferation. Since these calpains may have different functions in the mammary gland, we aimed to investigate the possible antagonistic roles of CAPN-1 and CAPN-2 in breast cancer progression, focusing on their expression patterns and functional impact on cell proliferation.Methods and resultsWe analyzed breast cancer cell lines using immunoblotting and real-time cellular assays, showing that HCC1937 cells exhibit an opposite expression pattern of CAPN-1 and CAPN-2 compared to non-cancerous breast cells. CAPN-1 promoted cancer cell survival and negatively regulated CAPN-2 at both the protein and mRNA levels, whereas CAPN-2 suppressed proliferation. Additionally, the calpain activator AG-08 triggered cell death through CAPN-2 but not CAPN-1. In silico analysis confirmed higher CAPN-1 and lower CAPN-2 expression levels in breast cancer samples compared to normal tissue.ConclusionsThese findings indicate that CAPN-1 and CAPN-2 may exert antagonistic roles in breast cancer, but importantly, this effect was restricted to HCC1937 cells, representing a basal A TNBC subtype. Validation in additional basal A models and patient-derived samples will be essential to confirm these results. Our study, therefore, provides preliminary, model-specific insights into calpain regulation in TNBC and suggests that future therapeutic strategies should carefully account for subtype heterogeneity.
  • Article
    Enhancement of Corchorus Olitorius L. on Osteogenic Differentiation of MC3T3-E1 Pre-Osteoblast Cells by Increasing Alkaline Phosphatase and Hydroxyproline
    (Taylor & Francis Ltd, 2025) Ertugruloglu, Pinar; Baris, Elif; Okkali, Gaye Sumer; Boke Sarikahya, Nazli
    Corchorus olitorius L. (jute mallow or molehiya) belongs to the Malvaceae family valued for its nutritional and medicinal properties. In this study, the potential to enhance osteogenesis in MC3T3-E1(Murine Calvaria-derived 3T3 Subclone E1) pre-osteoblastic cells was investigated to support bone formation and mineralisation. Leaf ethanolic extract was prepared and applied to MC3T3-E1 cells. Osteogenic effects were evaluated through three methods: MTT assays for cell viability, Alizarin Red S staining for calcium deposition, enzymatic analyses for alkaline phosphatase (ALP) and hydroxyproline (HYP). A non-cytotoxic concentration of C. olitorius extract (0.5 mg/mL) significantly increased ALP and HYP levels, promoting osteogenic differentiation in both undifferentiated and differentiated cells. HYP levels were notably elevated in differentiated cells. The findings suggested that C. olitorius extract may be a promising natural agent for enhancing bone health, warranting further in vivo and clinical studies to confirm its therapeutic potential.
  • Article
    Balance of Bunch Compression and Emittance Preservation for High-Brightness X-Ray Free Electron Laser Injectors
    (Amer Physical Soc, 2025) Davut, C.; Apsimon, O.; Hounsell, B. R.; Militsyn, B. L.; Cowie, L. S.; Yaman, F.; Williams, P. H.
    This paper presents two conceptual low-energy injector configurations optimized for high-brightness, high-repetition-rate XFELs. The designs were evaluated at a nominal bunch charge of 150 pC using multiobjective optimization techniques and further assessed through start-to-end simulations incorporating collective effects to determine their suitability for delivering high-brightness beams under FEL-relevant conditions. One of the injector design configurations employs a hybrid rf and magnetic compression scheme, while the second relies solely on two-stage rf compression. Start-to-end simulations through the main linac, including collective effects, were performed to assess the suitability of each design for meeting XFEL requirements. The results highlight the critical role of longitudinal charge distribution symmetry in maintaining beam quality during acceleration and compression, and demonstrate that appropriately balancing compressibility, emittance preservation, and phase space linearity is essential for meeting the stringent demands of XFEL operation.
  • Article
    Benzoxazine-Linked Porous Organic Networks for Effective Iodine Capture
    (Royal Soc Chemistry, 2025) Canturk, Batu Sercan; Erdogmus, Mustafa; Gecalp, Yasmin; Sahin, Hasan; Buyukcakir, Onur
    This study presents, for the first time, the investigation of a benzoxazine-linked porous organic network (BPON) for iodine capture. BPON was synthesized through the Mannich condensation of paraformaldehyde, melamine, and phloroglucinol. The porous structure and heteroatom-rich skeleton of BPON make it a promising adsorbent platform for iodine capture. BPON demonstrated an effective iodine capture capability in the vapour phase (3.32 g g-1) and an impressive uptake capacity in the aqueous phase (2.80 g g-1 capacity, 90.4% removal efficiency in 12 hours). To investigate the effect of curing on iodine capture, BPON was thermally cured to prepare thermally cured benzoxazine-linked porous organic networks (cBPONs) at three different temperatures: 200, 250, and 300 degrees C. cBPONs demonstrated an iodine capture capacity of up to 2.20 g g-1 and 1.67 g g-1 for vapour and aqueous phases, respectively. The iodine capture mechanism of BPON was investigated using various ex situ analyses, including Fourier transform infrared (FT-IR), Raman spectra, and X-ray photoelectron spectra (XPS). Structural analysis and theoretical calculations indicated the formation of a charge-transfer complex upon iodine capture, leading to the generation of polyiodide species. This study demonstrates the potential of BPONs for iodine capture and paves the way for developing new polymeric adsorbents for capturing iodine from air and water.