IYTE GCRIS Database (Izmir Institute of Technology)
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Investigation of LiCoO2 Thin Films Grown Under Relatively Low Substrate Temperature for All Solid State Lithium Ion Battery Applications
No full textThis study examines the effect of substrate temperature on the surface, structural and chemical properties of LiCoO2 (LCO) thin films deposited via magnetron sputtering. LCO thin films were grown for the purpose of being a cathode layer for all-solid-state lithium-ion batteries (ASSLIBs). Achieving crystalline LCO films at low substrate temperatures is advantageous for integration with flexible and temperature-sensitive substrates as well as minimizing energy consumption, which is highly important for industrial applications. In this work, LCO thin films were deposited on titanium-coated soda lime glass (SLG/Ti) at the substrate temperature ranging from room to 350 degrees C. Structural characterizations by XRD analyses confirmed that LCO thin films have (104) crystal orientation, which is critical for efficient lithium-ion transportation. SEM, Raman, and XPS analyses were used for further chemical and structural characterizations of grown LCO thin films. These analyses showed that LCO thin film grown at relatively low substrate temperature of 250 degrees C is a better growth condition when compared to others. Crystallization orientation (104) of LCO thin films is highly important for the potential usage of ASSLIBs technologies without any need of elevated temperatures. Moreover, results support the low-temperature adaption processes for applications like wearable electronics, offering safer and more sustainable solutions for future energy storage systems
Multiorgan-On for Cancer Drug Pharmacokinetics-Pharmacodynamics (pk-Pd) Modeling and Simulations
No full textCancer is one of the most common and fatal diseases worldwide and kills millions of people every year. Cancer drug resistance, lack of efficacy, and safety are significant problems in cancer patients. A multiorgan-on-a-chip (MOC) device consisting of breast and liver compartments was designed with AutoCAD software. The MOC molds were printed by a Formlabs Form 2 3D printer. MDA-MB-231, HepG2, and MCF-10 A cells were used for the MOC experiments. The cell lines were cultured at 37 degrees C with 5% CO2, and cell viability was assessed via Alamar blue dye to generate pharmacodynamics (PD) data. Drug concentrations from the cell culture media were analyzed via Agilent 1260 Infinity II HPLC with a Waters Symmetry C18 column and used to generate pharmacokinetics (PK) data. The PK and PD data were modeled and simulated by Monolix and Simulix software, respectively. The safety and efficacy of drug dosing regimens were compared, and the best dosing regimens were selected. This research designed and fabricated a unique MOC consisting of liver and breast compartments that overcomes the need for sealing or assembling. It was used for PK-PD modeling and simulations, and its functionality was proven experimentally. The new MOC will be helpful in preclinical trials to evaluate the efficacy and safety of drugs
Long-Term Outcomes of Türkiye's First Population-Based Mammography Screening Program: a Decade of Breast Cancer Detection and Survival Analysis in Bahçeşehir
No full textBackgroundThe Bah ; ccedil;e ; scedil;ehir population-based mammography screening program (BMSP) is an example of T ; uuml;rkiye's first population-based screening program. This study aims to reveal the successful implementation of population-based secreening program in one of the low- and middle-income countries, T ; uuml;rkiye and long-term results of patients diagnosed with breast cancer during BMSP. MethodsThis study was conducted between 2009 and 2019, in the Bah ; ccedil;e ; scedil;ehir county of Istanbul. Women between the ages of 40 and 69 living in this region were invited every two years to undergo clinical breast examination (CBE) and mammography screening. All data was recorded in a dedicated software program. Women diagnosed with breast cancer were followed as a separate cohort. ResultsDuring the 10-year screening period, 8,825 women were screened and 146 (1.7%) breast cancers were detected. The median age at diagnosis for these patients was 52.9 years (40-69). The risk of breast cancer was 1.39 times higher (95% CI: 1.01-1.93) in women aged >= 50 compared to those less than 50 years (p = 0.045). The Cox regression analysis revealed that age at first birth, and number of births were significant predictors of breast cancer risk (p 0.001, and p = 0.011). The breast cancer rate tends to increase as the breast density category progresses from A to D (p 0.001). The median follow-up time for 146 breast cancer patients was 95.3 months. The 10-year breast cancer specific survival rate was 85%. ConclusionsThis study demonstrates that with a committed team and sufficient infrastructure, screening mammography can be effectively carried out in T ; uuml;rkiye, leading to early detection and lower mortality rates. The recommended age to commence screening is 40 years old
Pen Holder Design for a Handwriting Education Assistance Robot
No full textThe aim of this work is to contribute to quality education by developing a robot system that can assist in handwriting education. The effects of educational robots on learning motivation and performance enhancement have been proven by various studies. In this context, the handwriting assistive robot aims to ease the work of teachers by enabling students to learn how to write more easily and to provide a platform where students can learn on their own. This robot can contribute to the spread of quality education by supporting equal educational opportunities, especially in disadvantaged areas and in cases where the number of teachers is insufficient. The robot supports three different operation modes: Active Mode, Assistive Mode, and Passive Mode. In this study, the pen holder design of this robot is presented. The final design is suitable for both right- and left-handed users, does not require an additional sensor, and the writing ergonomics is increased by keeping the contact point of the pen with the paper at a constant point independent of the holding style. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025
A Cinematic Narration of Urban Segregation Through Migration in Turkey: an Analysis of the Film Block-C Directed by Zeki Demirkubuz
No full textMetropolitan life is always one of the major concerns of modernity as well as the set for the cinematic art. The critical gaze of cinema throws a light on how cities provide various social and architectural contexts for diversified groups as an indispensable part of the scenario. This study delves into the portrayal of metropolitan life in Zeki Demirkubuz’s 1994 film C Blok (Block-C) through the intertwined concepts of spatial alienation, urban segregation and urban migration. Situated within the context of 1990s Istanbul, the film serves as a microcosm for exploring the social and architectural landscape of Turkish modernity. It scrutinizes the interactions between diverse social classes residing in a suburban apartment complex, offering critical insights into how western-style modernization has shaped urban spaces and individual experiences. In this context, the theoretical foundation of this research encompasses the advent of western-style modernization in Turkey, its permeation into societal realms, and the concept of spatial alienation at the social stratum. Moreover, adopting a critical thinking perspective, this study probes the notions of home and house, elucidating their implications for individuality within the framework of spatial alienation. © 2025 Intellect Ltd
Effective Geometry of Bell-Network States on a Dipole Graph
No full textBell-network states are a class of entangled states of the geometry that satisfy an area-law for the entanglement entropy in a limit of large spins and are automorphism-invariant, for arbitrary graphs. We present a comprehensive analysis of the effective geometry of Bell-network states on a dipole graph. Our main goal is to provide a detailed characterization of the quantum geometry of a class of diffeomorphism-invariant, area-law states representing homogeneous and isotropic configurations in loop quantum gravity, which may be explored as boundary states for the dynamics of the theory. We found that the average geometry at each node in the dipole graph does not match that of a flat tetrahedron. Instead, the expected values of the geometric observables satisfy relations that are characteristic of spherical tetrahedra. The mean geometry is accompanied by fluctuations with considerable relative dispersion for the dihedral angle, and perfectly correlated for the two nodes. © 2024 IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved
Seismic Testing and Modeling of Full-Scale Substandard Rc Columns Retrofitted With Sprayed Gfrm With and Without Basalt Mesh Under High Axial Compression and Shear Demand
No full textThis study presents the experimental and analytical hysteretic behaviors of eight full-scale RC square and rectangular columns. The columns were designed to have different shear spans that represent: (1) a column that complies with the Turkish Government Ministry of Reconstruction and Resettlement's ( 1975) seismic design code, Turkish Seismic Design Code (TSDC); (2) a substandard column; and (3) two sprayed glass fiber-reinforced mortar (GFRM)-retrofitted counterparts of the substandard column with and without basalt mesh. The substandard columns were designed to be subjected to relatively high shear ratios (i.e., the ratio of the shear force that corresponds to the moment capacity to shear strength of the cross section) up to 0.85 and with a high axial load-to-capacity ratio of 0.75. All columns were tested under constant axial load and reversed cyclic lateral displacement excursions. The results revealed that the columns that complied with the TSDC showed satisfactory behavior for seismic performance, and the performance of the substandard columns was extremely poor. However, the hysteretic performance of the substandard columns that were subjected to high axial stress and shear significantly improved after the proposed retrofitting. Finally, a numerical model was developed in OpenSees to reproduce the hysteresis curves of the specimens. The slip of the longitudinal bars at the column-foundation interface, strain penetration into the foundation, and buckling of the longitudinal bars in compression were accounted for in the modeling. The results are in good agreement with the experimental hysteresis curves. The performance levels of the columns are further specified, and the predictions of the current seismic codes were analyzed: (1) the European Committee for Standardization's 2005 code, Eurocode 8: Design of structures for earthquake resistance; Parts 1-3: Strengthening and repair of buildings (EC8-3); and (2) the Turkish Government Ministry of Interior Disaster and Emergency Management Authority's 2018 code, Turkish Building Earthquake Code (TBEC). The TBEC provided more accurate estimates of plastic rotation capacities for substandard specimens. In contrast, EC8-3 overestimated the plastic rotation capacity when shear stresses were relatively high due to lower shear span-to-depth ratios (a/d)
Effect of Soil Water Content Changes on the Behavior of Buildings Equipped With Single and Double Tuned Mass Dampers Subjected To Earthquakes
No full textTuned mass dampers (TMDs) are one of the structural control systems that have been frequently used in the last century. A TMD is designed according to the properties of the main system. In building applications, the substructure’s soil affects the response of buildings, especially in soft-type soils. Therefore, the soil properties should be included in the analysis and design of tuned mass dampers. However, the soil properties are not always identical and vary due to different factor changes such as soil water content changes. Unlike previous research, which typically assumes constant soil properties, this study incorporates the impact of soil water content changes, a key factor that can significantly alter soil behavior. This study aims to evaluate the effectiveness of optimized single and double tuned mass dampers (DTMDs) in response reduction of buildings considering the changes in the water content of soil. In this study, a metaheuristic-based optimization method is programmed to optimize TMDs and DTMDs for low-, mid-, and high-rise buildings considering soil-structure interaction (SSI). The efficiency of the optimized tuned mass dampers on the response reduction of buildings due to changes in soil water content is evaluated. According to the investigated results of 14 near-field earthquake simulations, it is concluded that the efficiency of the TMDs is significantly affected by changes in soil water content. Moreover, according to the result, the DTMD efficiency is slightly better than the TMD-controlled structure. © Springer Nature Switzerland AG 2025
Cradle-To Life Cycle Assessment of Heavy Machinery Manufacturing: a Case Study in Türkiye
No full textPurpose: Amidst accelerated industrialization and urbanization, the surge in heavy equipment production, crucial for construction, mining, industry, and transportation, necessitates a comprehensive examination of its environmental implications from a sustainability standpoint. This study aims to scrutinize the environmental impacts of manufacturing forklifts and semi-trailers in Türkiye, employing the life cycle assessment (LCA) methodology. Methods: The life cycle assessment (LCA) methodology is the foundational framework for evaluating the environmental impacts associated with forklift and semi-trailer manufacturing. A cradle-to-gate approach was employed. CCaLC2 software alongside the Ecoinvent 3.0 database and CML LCIA methodology was used. Results: The carbon footprint analysis reveals that the production of a single forklift and semi-trailer generates 10.8 tons CO2eq. and 24.9 tons CO2eq. of emissions, respectively. Considering the mass of the machinery, these figures translate to 2.8 ton CO2eq./ton machinery and 1.57 ton CO2eq/ton machinery for the forklift and semi-trailer, respectively. These results were found to be consistent with values reported for similar (but not identical) heavy machinery. Notably, the predominant share of environmental impact stems from raw material acquisition for both products, with subsequent contributions from various production stages. Steel utilization emerges as the primary contributor to all environmental impact categories, constituting an average contribution of 75%. Noteworthy exceptions include the acidification potential of forklift production, where the incorporation of the engine emerges as the primary hotspot with a significant 38% contribution. Conclusions: The findings present the environmental footprint associated with forklift and semi-trailer manufacturing, emphasizing the pivotal role of raw material acquisition, particularly steel utilization. Insights derived from this environmental impact assessment provide invaluable guidance for enhancing environmental sustainability. Decision-makers and industry stakeholders can leverage these conclusions to implement targeted measures, such as exploring alternative materials or refining production processes, to mitigate the environmental consequences of resource-intensive heavy equipment manufacturing, aligning with broader sustainability objectives. © The Author(s) 2025
New Copper and Cobalt Complexes Based on a Fluorinated Pyrazole Derivative, Synthesis, Characterization and Antibacterial Activity
No full textTwo copper and cobalt complexes based on 3-(trifluoromethyl)-4-((3-(trifluoromethyl)phenyl)diazenyl)-1H-pyrazol-5-ol (Httdp) have been prepared and characterized using different physicochemical techniques. The crystal structure of the copper complex has been proven to be a square pyramidal, and the cobalt complex has an octahedral structure. DFT calculations of the complexes were performed, and the energy gaps between the HOMO-LUMO of the complexes (-3.38676 to -3.18138 eV) and the Cu (II) complex reflect a higher relative stability compared with Httdp and the Co (II) complex. The antibacterial activities of the two complexes were evaluated. The Co (II) complex demonstrated the highest antibacterial activity against various bacteria compared with Httdp and the Cu (II) complex. The mean inhibition zones exhibited by the Co (II) complex showed the highest activities toward the Gram-negative bacterial strains with mean inhibition zones of 30.3 +/- 0.6 (Staphylococcus aureus) and 25.7 +/- 0.6 (Bacillus subtilis) mm. Docking studies were carried out using S. aureus tyrosyl-tRNA synthetase (PDB ID: 1JIJ) to assess the antimicrobial activities, proving that the complexes were efficient for the protein