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Superconducting Properties of Welded Three Top-Seeded YBa2Cu3O7−x Produced with NdBCO/YBCO/MgO Thin-Film Seed
No full textThis study investigates hollow single-crystal top-seeded melt growth (TSMG) YBa2Cu3O7−x (YBCO or Y123) samples welded with Ag-added TSMG YBCO solder materials produced using NdBCO/YBCO/MgO thin-film seeds. Three main samples and one solder material are produced by the TSMG method. In order to increase the dimensions of the bulk YBCO superconductor, two slices of the solder material and the main samples are stacked on top of each other with the c-axis parallel and welded at 1030 °C. X-ray diffraction patterns, polarized optical photographs, and SEM micrographs are taken to determine the structural properties of the samples. A preferential orientation in the c-axis is observed with a good connection. Low-temperature resistance and magnetization measurements are made for the specimens taken from the welding region. A sharp superconducting transition occurs at 0 T around 93 K for welding regions of W-ab and W-bc specimens. The critical current densities (Jc) are high as in the main samples. At the same time, the Jc values at 77 K and 0 T are found as 1.54 × 104, 1.98 × 104, 2.21 × 104, 2.31 × 104, and 2.36 × 104A cm−2 for the W-a, W-ab, W-b, W-bc, and W-c specimens, respectively. The single-grain feature is not impaired; thus, the absence of additional grain boundaries facilitates the current passage. © 2024 Wiley-VCH GmbH
Availability of sedimentary and volcanic rock deposits on Northeastern Turkey as concrete aggregates
No full textTurkey has large aggregate deposits; however, these deposits cannot be used effectively due to a lack of controls. This can lead to fatal errors, as in the 6 February 2023 Turkey-Syria earthquakes. The main motivation of this study is to investigate the availability of existing and new aggregate deposits as concrete aggregates in northeastern Turkey. Thus, the quality of aggregates in this region will be studied comparatively. This research was carried out with aggregate samples taken from 30 different rock quarries in 10 different provinces in this region of Turkey. First, the locations of 30 crushed rock aggregates were identified, and their petrographic, mineralogical, physical, geometric and durability properties were determined. Fifteen different test procedures were applied to 30 crushed rock samples. It was concluded that these rocks are generally sedimentary rock types and that 18 of these 30 samples are of limestone origin. To obtain high-strength concrete, in addition to quality cement, the aggregates used must also be of high quality. The use of aggregate resources mentioned in this study for building concrete will contribute to the production of high-strength concrete. These samples, which generally have sufficient physical, mechanical and durability properties, meet the limitations of the standards much better than concrete aggregates. High-statistical-performance regression equations were obtained for the physical and durability properties. © 2024 Elsevier Lt
[SOBRE O OMBUDSMAN DOS GOVERNOS LOCAIS NA TURQUIA: UMA ANÁLISE COMPARATIVA COM O OMBUDSMAN DOS GOVERNOS LOCAIS NO REINO UNIDO E NA ITÁLIA] [SOBRE EL OMBUDSMAN DE LOS GOBIERNOS LOCALES EN TURQUÍA: UN ANÁLISIS COMPARATIVO CON EL OMBUDSMAN DE LOS GOBIERNOS LOCALES EN EL REINO UNIDO E ITALIA]
No full textObjective: The Ombudsman is essentially an independent, national-level institution that operates in response to complaints from citizens in order to steer public administrations away from bad administrative practices and behavior. However, it is impossible for an ombudsman with such a broad mandate at the national level to deal with all administrative complaints within the state. Therefore, in order to get more efficiency from the national Ombudsman, it has been divided into different sub-types. Theoretical Framework: One of these is the Ombudsman for local governmentrs, which deals only with complaints from local administrations. Although there is a national ombudsman in Turkey, there is no ombudsman specialized in local governments. Method: This study aims to make some suggestions for the Ombudsman for local governments envisaged to be established in Turkey in the future by analyzing the local governments ombudsman offices in the UK and Italy in terms of their structural-institutional and functional aspects. In this context, the study, with a comparative approach, provides suggestions for the basic aspects, qualities and characteristics of the Turkish local government ombudsman and, thus, for its structural-institutional and functional aspects. The method of the research is literature review. Results and Discussion: According to the results of this research; Establishing an ombudsman for local governments in Turkey by law, cooperating with other ombudsmen in the vicinity, examining and correcting the mismanagement and bad behavior of local governments upon public demand, ensuring easy and cheap access, fulfilling their duties, and quickly and systematically addressing the faults of local governments. Warning, making suggestions, preparing reports and then reporting the situation to local decision-making boards and the public will be effective in providing public services more effectively and efficiently and strengthening local democracy. Originality/value: In the study, original suggestions are made for local government ombudsman in Turkey, based on the examples of UK and Italy. © 2024 ANPAD - Associacao Nacional de Pos-Graduacao e Pesquisa em Administracao. All rights reserved
L0-Norm based Image Pansharpening by using population-based algorithms
No full textEarth observation satellites capture panchromatic images at high spatial resolution and multispectral images at lower resolution to optimize the use of their onboard energy sources. This results in a technical necessity to synthesize high-resolution multispectral images from these data. Pansharpening techniques aim to combine the spatial detail of panchromatic images with the spectral information of multispectral images. However, due to the discrete nature of these images and their varying local statistical properties, many pansharpening methods suffer from numerical artifacts such as chromatic and spatial distortions. This paper introduces the L0-Norm-based pansharpening method (L0pan), which addressed these challenges by maximizing the number of similar pixels between the synthesized pansharpened image and the original panchromatic and multispectral images. L0pan was optimized using a population-based colony search algorithm, enabling it to effectively balance both chromatic fidelity and spatial resolution. Extensive experiments across nine different datasets and comparison with nine other pansharpening methods using ten quality metrics demonstrated that L0pan significantly outperformed its counterparts. Notably, the colony search algorithm yielded the best overall results, highlighting the algorithm’s strength in refining pansharpening accuracy. This study contributed to the advancement of pansharpening techniques, offering a method that preserved both chromatic and spatial details more effectively than existing approaches. © 2024, American Institute of Mathematical Sciences. All rights reserved
Potential geographic distribution and habitat utilization of Lacerta viridis (Squamata: Lacertidae) in northern Türkiye
No full textThe genus Lacerta, particularly the green lizard (Lacerta viridis), is a significant lizard group in the Western Palearctic. This study aims to predict its geographic range in Northern Türkiye and identify key habitat types based on the CORINE Land Cover classification. Occurrence records, gathered from published sources and on-site investigations, were analyzed using a 30 arc-second resolution layer and bioclimatic parameters from WorldClim v.2.1. The distribution was modeled in kuenm, and habitat use was assessed with generalized linear models. Results show that the green lizard’s occurrence is strongly influenced by precipitation dynamics and it prefers areas with little to no shade. These findings highlight the importance of precipitation in determining the species’ distribution and suggest further research on local dynamics for effective conservation. © 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group
Green synthesis of iron and silver nanoparticles from aqueous extract of buckwheat husk waste: antibacterial, cytotoxic, and dye decolorization properties
No full textIron oxide (BHFeNP) and silver nanoparticles (BHAgNP) were produced using a green synthesis method through the extract of buckwheat husk (BH) waste to remove dye pollutants from water bodies in this study. The BHFeNP and BHAgNP were characterized by TEM, SEM, XRD, EDX, and FTIR techniques. Then, the methylene blue (MB) removal performance of the synthesized nanoparticles (NPs) was investigated. MB adsorption experiments showed that BHFeNPs were more dependent on temperature, adsorbent amount, and pH, while BHAgNPs notably depended on adsorbent amount, initial MB concentration, and pH. BHAgNPs had higher adsorption rates than BHFeNPs, and the Langmuir isotherm was more suitable for the adsorption process. BHAgNP and BHFeNP were shown to have the maximum adsorption capacities of 96.3 and 53.4 mg/g at pH 8 and 25 °C, respectively, in the presence of 0.25 g/L NP. Kinetic and thermodynamic calculations revealed that MB adsorption was spontaneously endothermic and supported the pseudo-second-order kinetic model. The antibacterial potentials of BHFeNPs and BHAgNPs were investigated against two gram-negative (Escherichia coli and Pseudomonas aeruginosa) and two gram-positive (Enterococcus faecalis and Staphylococcus aureus) bacterial strains. BHAgNPs exhibited a higher antibacterial activity against the strains used. In cytotoxicity studies with ARPE-19, A549, HeLa, and DU-145 cell lines, it was observed that BHAgNP had a greater cell growth inhibition effect than BHFeNP and BH extract. Examining the morphological changes in the cells exhibited that BHAgNP significantly inhibited A549 and ARPE-19. Reusability studies of the generated NPs revealed MB removal capabilities of 92.5% and above after the fifth stage. The present study demonstrates that BHAgNP and BHFeNPs are viable nanoadsorbents for the elimination of environmental pollution due to their excellent removal performances and stable adsorbent characteristics. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024
Investigation of the Effects of Filling Speed, Casting Temperature and Metallurgical Quality on Fluidity of Lamellar Graphite Cast Iron at Different Section Thicknesses
No full textIn this study, the fluidity properties of the alloy were investigated at different casting temperatures, different section thicknesses, and varying casting parameters of lamellar graphite cast iron materials. To achieve our goal, we utilized sand molds that were created with specific parameters including pouring temperature, metallurgical quality, section thickness, and fluidity test model. These molds were used for casting. Thus, the effect of fluidity properties in changing casting conditions and liquid metal advance distances at determined section thicknesses was investigated. Modeling was carried out with FlowCast casting simulation software by determining the liquid metal advance distance depending on the section thickness in the castings made in sand molds under changing casting conditions. The fluidity and advance distance of the liquid metal was determined comparatively with experimental and modeling techniques under the changing casting conditions in the parameters determined in this study. When the outcomes were examined; it was observed that different liquid metal advance distances occur at different cross-section thicknesses depending on the changing conditions. © The Author(s) 2024
Earthquake diaries: Psychosocial difficulties and life experiences of nurses working in the disaster zone after the earthquake: A phenomenological study
No full textAim and Objectives: The aim of this study was to evaluate the psychosocial difficulties and life experiences of nurses working in the disaster area following the earthquake on February 6, Kahramanmaraş centered earthquake with a phenomenological approach. Background: After natural disasters such as earthquakes, nurses play a significant role in providing both physical and psychosocial support. Therefore, the experiences of nurses in this field are necessary both to support them and to assist disaster survivors. Materials and Methods: In this study, in which the phenomenological research method was used, semi-structured in-depth interviews with 18 nurses who provided health care services during the February 6 Kahramanmaraş earthquake were conducted between January and February 2024 via Whatsapp mobile application. Snowball sampling method was used to reach the sample group. Interviews continued until data saturation was achieved. All interviews were audio recorded and then transcribed. The data were analyzed using thematic analysis. The study was conducted and reported according to the COREQ checklist. Results: Data analysis revealed two themes (psychological and social difficulties caused by the earthquake, traumatic stress and coping experiences as a nurse) and five sub-themes (social difficulties, psychological difficulties, traumatic events, reactions and coping). Conclusion: As a result of the study, it was determined that nurses providing health care services were negatively affected psychosocially by the traumatic stress situations they experienced in the earthquake centered in Kahramanmaraş on February 6. It was determined that nurses had great difficulty in coping with the traumatic stress situations they experienced. It was concluded that the February 6 earthquake caused secondary traumatization in nurses. © 2024 The Author(s). Public Health Nursing published by Wiley Periodicals LLC
Remote sensing and monitoring of water resources: A comparative study of different indices and thresholding methods
No full textWater resources are essential for the ecological system and the development of civilization. Water is imperative factor for health preservation and sustaining various human activities, including industrial production, agriculture, and daily life. Remote sensing provides a cost-effective and practical means to detect and monitor water bodies, offers valuable insights into the impact of climatic events on water structures, especially in coastal lake regions. The research primarily utilizes Landsat-9 OLI-2 satellite images to evaluate the effectiveness of various water indices (WRI, NWI, MNDWI, NDWI) in combination with global automatic thresholding methods (K-Means, Zhenzhou's, Adaptive, Intermodes, Prewitt and Mendelsohn's Minimum, Maximum Entropy, Median, Concavity, Percentile, Intermeans, Kittler and Illingworth's Minimum Error, Tsai's Moments, Otsu's, Huang's fuzzy, Triangle, Mean, IsoData, Li's). The study was carried out on Lake Nazik, Lake Iznik, and Lake Beyşehir, which have unique geographical characteristics, and examined the adaptability and robustness of the selected indices and thresholding methods. MNDWI consistently stands out as a robust index for water extraction, delivering accurate results across different thresholding methods in regions all three lakes. As a result of quite extensive analysis, it is obtained that MNDWI and NDWI are reliable choices for water feature extraction in various lake environments, but the specific index should consider the thresholding method and unique lake characteristics. The Minimum thresholding method stands out as the most effective thresholding technique, demonstrating impressive results across different lakes. Specifically, it achieved an average Peak Signal-to-Noise Ratio (PSNR) of 78.97 and Structural Similarity Index (SSIM) of 99.37 for Lake Nazik, 74.08 PSNR and 98.34 SSIM for Lake Iznik, and 63.96 PSNR and 93.61 SSIM for Lake Beyşehir.3856534
Factors Affecting the Mental Health of Youth After the Great Kahramanmaras Earthquake Disaster
No full textThis study aims to determine the extent of the psychological effects of the Kahramanmaraş earthquake disaster, which is widely regarded as one of the most significant disasters of the century, on young people based on their direct or indirect exposure and to investigate the impact of these issues on life satisfaction. Data were collected from 337 individuals who were continuing their advanced education at a state university in Turkey, using a demographic information form, life satisfaction scale and Depression Anxiety Stress Scales 21. In the analysis of the data, t-test, Pearson correlation test, ANOVA and multiple regression analysis were employed. The results of the analyses indicated that as the intensity of exposure to disaster news increased, the stress, depression, and anxiety levels of the participants also increased. Individuals who experienced the earthquake personally and participated in volunteer aid activities demonstrated higher depression and anxiety scores and DASS21 scale total scores than those who did not directly experience the earthquake but followed the news and those whose relatives experienced the earthquake. There was no significant difference in the intensity of following earthquake news between men and women among the participants. However, it was determined that the intensity of following earthquake news from media and social media tools positively and significantly predicted the life satisfaction of the participants. These findings provide insights for future mental health interventions and social work practices for young people affected by the earthquake. © 2024 Taylor & Francis Group, LLC