Scopus İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/395

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  • Article
    A Small Indole Derivative Isolated From Caper (Capparis Ovata) as an Inducer of P53-Mediated Apoptosis in Prostate Cancer: Comprehensive In Vitro and In Silico Studies
    (Wiley, 2025-12-31) Acar, Ozden Ozgun; Gazioglu, Isil; Oruc, Hatice; Kale, Elif; Senol, Halil; Topcu, Gulacti; Sen, Alaattin
    Natural products with stunning chemical diversity have been extensively researched for their anticancer potential for more than fifty years. This study aimed to determine the effect of indole derivative 1H-indole-2-hydroxy-3-carboxylic acid (IHCA), isolated as a novel alkaloid from Capparis ovata, on selected tumor suppressor, apoptotic, and cell cycle regulatory genes, which are known to be important in cancer pathophysiology, on Caco-2 and LNCaP cells in comparison with Taxol. The molecular mechanism of IHCA's anticancer activity is essentially undefined. Different concentrations of IHCA increased the expression levels of apoptosis-related genes, including BCL-2 and TNF-alpha. In addition, the tumor suppressor genes PTEN, P53, and RB were increased in LNCaP and Caco-2 cells. KRAS, an oncogenic gene, was significantly downregulated by IHCA in LNCaP cells. Western blot results showed that the protein expression levels of P53 and PTEN in LNCaP cells were increased when treated with IHCA, whereas CDK4 and TNF-alpha were decreased. Finally, IHCA and doxorubicin significantly increased P53-driven luciferase activity compared to the control. The results strongly suggest that the novel natural compound IHCA has an anticancer effect involving the regulation of the P53 gene and its networks in vitro. The molecular docking and MD simulation analyses reveal that IHCA exhibits superior binding potential to the MDM2 protein compared to Nutlin-3a. MD simulations further confirm that IHCA maintains a more stable and consistent interaction with MDM2, as indicated by lower RMSD values and reduced ligand fluctuation. These results highlight IHCA's potential as a more effective MDM2 inhibitor, suggesting its promise as a lead compound for anticancer drug development.Clinical Trial Registration: Not applicable.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    A Comprehensive Review on the Extraction and Recovery of Lithium from Primary and Secondary Sources: Advances Toward Battery-Grade Materials
    (Wiley, 2025-10-20) Top, Soner; Kursunoglu, Sait; Altiner, Mahmut
    Lithium-ion battery (LIB) technologies have become indispensable to modern energy systems, driving global demand for high-purity lithium compounds. This review focuses on lithium recovery and purification strategies for battery-grade lithium carbonate (Li2CO3) and lithium hydroxide (LiOH), addressing both primary sources (brines and minerals) and secondary sources (waste materials). Industrially established processes, such as evaporation-based brine treatment and conventional metallurgical methods, are discussed alongside emerging techniques, including membrane separation, solvent extraction, and CO2-assisted precipitation. Particular attention is given to lithium precipitation mechanisms, the behaviour of co-existing ions during extraction, and the specific quality requirements for cathode material synthesis. By evaluating process scalability, environmental impact, and product purity, this review provides a comprehensive understanding of current practices and future directions. Additionally, it highlights the growing importance of lithium in the context of accelerating electric vehicle (EV) adoption, underscoring the bright and expanding future of the lithium industry.
  • Article
    Citation - WoS: 7
    Citation - Scopus: 7
    Villages in the City - Urban Planning for Neighbourhood Love
    (Wiley, 2024-03-17) Kourtit, Karima; Nijkamp, Peter; Turk, Umut; Wahlstrom, Mia
    The city comprises of a wide variety of heterogeneous territorial units (e.g. districts or neighbourhoods). In many - especially larger - cities, social capital assets (like community bonds) are mirrored at the level of neighbourhoods which form the home for many sociocultural communities or distinct socio-economic classes. We postulate in this study that the big city is essentially an 'archipelago' made up of 'urban villages'. We analyse the residents' perceived attractiveness regarding their daily local neighbourhood by introducing the concept of 'village love' (or 'neighbourhood love'), inspired by the recent literature on 'city love' (comprising 'body', 'soul' and 'community' constituents of urban life). Based on an extensive and detailed multi-annual database for all neighbourhoods in Rotterdam, the present paper seeks to identify the background factors shaping 'village love' in the city, with particular attention to the citizens' subjective appreciation for and access to a great variety of (physical and immaterial) urban amenities shaping the place-based satisfaction of residents. The theoretical framing of our research resembles the basics of traditional central place theory here transmitted to the urban space in which local proximity to amenities plays a key role. A wide array of relevant amenities impacting on the place-specific well-being feelings ('village love') of residents in various neighbourhoods in the city of Rotterdam is distinguished using inter alia-rich multi-annual survey data. This approach is empirically tested and verified by means of LISA statistics and advanced spatial econometric dependence models ('urbanometrics'). The findings confirm the usefulness of a central place interpretation of 'urban village love' in the city. 'Villages in the City - Urban Planning for Neighbourhood Love': This study advocates that cities are composed of interconnected 'urban villages', each with its own social capital and community bonds. Using extensive data from Rotterdam, we investigate the factors influencing residents' perceived attractiveness and satisfaction with their local neighbourhoods. Our analysis highlights the importance of access to diverse amenities in shaping residents' sense of 'village love'. Through spatial econometric models, the study confirms the central place interpretation of 'urban village love' in the city, shaping future urban planning strategies for fostering vibrant and cohesive communities.image
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Unhappiness Among the Unemployed: The Roles of Descriptive Norms, Injunctive Norms and Personal Beliefs
    (Wiley, 2025-05-19) Ugur, Zeynep B.; Durak, Aysenur
    This study explores the influence of social norms and individual beliefs on the well-being of unemployed individuals in Turkey, a context marked by both chronic unemployment and a high societal valuation of employment. Using province-level representative data from the 2013 Life Satisfaction Survey, encompassing 196,203 observations, we analyse how descriptive norms (prevalence of unemployment) and injunctive norms (social pressures due to unemployment) at the province level affect the happiness of the unemployed. We utilized people's perception of employment for being respected in social life and personally feeling social pressure as a measure of individual beliefs. Multilevel regression results reveal that descriptive norms can modestly alleviate the adverse impact of unemployment, particularly for the short-term unemployed, while injunctive norms slightly intensify the unhappiness of being unemployed, especially in the short term. The unemployed's personal beliefs about the value of employment matter for their happiness. These findings underscore the theoretical implications of social norms in shaping the well-being of the unemployed and highlight the importance of individual beliefs in moderating these effects.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Uncovering Nanoclusters in Amorphous AlN: An Ab Initio Study
    (Wiley, 2014-12-22) Durandurdu, Murat
    Amorphous AlN (a-AlN) is modeled by melt-and-quench technique using ab initio molecular dynamic simulations. For the first time, three-dimensional hexagonal-like nanoclusters embedded in amorphous matrix are proposed for a-AlN. The model is chemically ordered and dominantly fourfold coordinated, but its short-range order is partially different from the crystalline morphology due to the nanoclusters. The model is semiconducting with a theoretical band gap of 1.7eV.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Two Successive Amorphous-to Phase Transformations in TiO2
    (Wiley, 2017-05-22) Durandurdu, Murat
    Based on constant pressure ab initio simulations, we propose, for the first time, two successive amorphous-to-amorphous phase transformations for TiO2. The first one is a gradual phase transformation from a low-density amorphous phase to a high-density amorphous phase, whereas the second one is a first-order phase transformation from the high-density amorphous phase to a very high-density amorphous phase. The low-density amorphous to high-density amorphous phase change is irreversible, whereas the high-density amorphous to very high-density amorphous phase transformation is reversible. The high-density amorphous and very high-density amorphous phases consist of differently coordinated configurations. The sevenfold and ninefold-coordinated arrangements formed in amorphous TiO2 under pressure are similar to the main building motif of the baddeleyite and cotunnite polymorphs of TiO2, respectively, while the eightfold-coordinated configuration is different from the local structure of the cubic TiO2 phase. The electronic structure calculations suggest that both dense amorphous phases present a semiconducting character with a band gap energy less than that of the original low-density amorphous phase.
  • Article
    Citation - WoS: 4
    Citation - Scopus: 6
    Traffic Aware Cyclic Sleep-Based Power Consumption Model for a Passive Optical Network
    (Wiley, 2022-02-28) Butt, Rizwan Aslam; Faheem, Muhammad; Anwar, Muhammad; Mohammadani, Khalid H.; Idrus, Sevia M.
    For a network, a power consumption model is an important tool to test the performance of a network process for different traffic loads. In a Passive optical network (PON), the optical network unit (ONU) is responsible for the major power consumption of PON. Both IEEE and ITU have standardized a cyclic sleep process (CSP) for ONU energy conservation. In next-generation PON; TWDM and XGS PON, the ONU power contribution has increased further due to higher number of ONUs and ONU being tunable. Therefore, an accurate power consumption model of the CSP process for energy efficiency studies under different traffic conditions is of prime importance. The existing CSP power consumption models do not depict the CSP process accurately especially the inactivity of the ONU in the asleep and sleep aware states are not taken into account which reduce the accuracy of the model. The proposed inactivity aware model (IAM) overcomes these gaps and very accurately models the CSP process, as evident from the results, which are better than earlier model results and quite close to earlier published simulation results. The model is also validated through a simulation-based study and the simulation results are observed to be very close to the model results with only a 5% deviation.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    The Rise of Digital Responsibility: Insights From Türkiye's Banking and E-Commerce Sectors
    (Wiley, 2025-07-28) Aydogdu, Ceyda Cihan; Karsak, Banu Mujde Baskan; Baskan Karsak, Banu Mujde; Cihan Aydogdu, Ceyda
    This study examines how the concept of corporate digital responsibility (CDR) principles, such as data security, transparency, and digital inclusivity, is integrated into the corporate structures of the banking and e-commerce sectors in T & uuml;rkiye. The objective is to identify sector-specific key trends, challenges, and strategic approaches related to the adoption of CDR in corporate frameworks. By presenting a comparative analysis of two critical sectors, this research highlights the sectoral differences in understanding and implementing CDR. Employing a qualitative methodology, the research utilizes semi-structured interviews with senior executives, corporate communication directors, IT professionals, and legal experts. The interviews were thematically analyzed and digitized using Python-based coding tools to enhance analytical consistency and depth. The findings indicate that the banking sector demonstrates greater maturity in CDR awareness and an institutionalized approach to CDR, particularly in areas related to data security and regulatory compliance. Conversely, the e-commerce sector shows slower and more fragmented progress, lagging in the adoption and implementation of CDR principles. Both sectors require significant improvements to align with global CDR standards. The study also underlines the importance of cross-sector collaboration, government enforcement mechanisms, and user-driven demands in fostering responsible digital ecosystems. Future studies should employ quantitative methods to evaluate the regulatory and cultural influences on digital responsibility. Furthermore, research that focuses on consumer perspectives, the long-term development of regulatory compliance, and compares different emerging economies will help broaden the current literature on CDR.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    The Different Impacts of g-C3N4 Nanosheets on PVDF and PSF Ultrafiltration Membranes for Remazol Black 5 Dye Rejection
    (Wiley, 2023-08-02) Senol-Arslan, Dilek; Gul, Ayse; Dizge, Nadir; Ocakoglu, Kasim; Uzal, Nigmet
    Membranes combined with nanoparticles are an excellent combination capable of successfully removing various contaminants, such as dyes from wastewater while using very little energy and decreasing pollution. The present study reports an efficient approach for Remazol Black 5 (RB5) dye removal using composite graphitic carbon nitride nanosheets (g-C3N4), polysulfone (PSF), and polyvinylidene fluoride (PVDF) membranes. The membranes were prepared using the phase inversion method, with varying quantities of g-C3N4 nanosheets ranging from 0.1%, 0.2% to 0.3%. The prepared g-C3N4 nanosheets were characterized by FTIR, SEM analyses, and zeta potential measurements. FTIR and SEM studies, contact angle, water permeability, COD, and dye rejection measurements were used to characterize the g-C3N4 nanosheets embedded in PSF and PVDF membranes. After the addition of 0.3 wt% g-C3N4, the water flux of the 0.3 wt% g-C3N4 embedded PSF membrane was the highest, whereas the water flux of the 0.3 wt% g-C3N4 embedded PVDF membrane was the lowest. The ultrafiltration (UF) membrane's performance with g-C3N4 embedded showed an RB5 rejection rate of more than 80% and a COD removal efficiency of more than 45%. The results of the experimental filtration showed that RB5 rejection reached maximum values of 91.3% for 0.1 wt% g-C3N4/PSF, and 85.6% for 0.3 wt% g-C3N4/PVDF.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Tetrahedral Amorphous Boron Nitride: A Hard Material
    (Wiley, 2019-09-25) Durandurdu, Murat
    We generate a tetrahedrally coordinated amorphous boron nitride (BN) model by means of first principles molecular dynamics calculations and report its mechanical and electrical properties in detail. The amorphous configuration is almost free from chemical disorder and consists of about 20% coordination defects, similar to tetrahedral (diamond-like) amorphous carbon. Its theoretical band gap energy is about 2.0 eV, less than 4.85 eV estimated for cubic BN. The bulk modulus and Vickers hardness of tetrahedral amorphous BN are computed as 206 GPa and 28-35 GPa, respectively. Based on these findings, we propose that tetrahedral noncrystalline BN can serve as electronic and hard materials as well.