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Novel Developments of Wire-Feed Additive Manufacturing
No full textAdditive manufacturing of metallic parts has been separated into three basic categories such as powder bed systems, powder feed systems and wire feed systems. While powder bed systems are used for manufacturing of small 3D complex components because of their volumetric restrictions, powder and wire feed systems are preferred for production of large-scale metal workpieces. Wire-feed additive manufacturing method has been classified as laser-based, arc welding-based and electron beam-based according to used energy sources. Wire-feed additive manufacturing is a novel manufacturing research field due to its high material efficiency, material deposition rates and consideration as an environment-friendly manufacturing method. Recent investigations have been conducted on reducing of excessive heat input, residual stresses and distortions and improving of low part accuracy and last surface condition due to the “stair stepping” effect. Precise controlled droplet transfer with reducing the burning period of arc with short-circuit system called as Cold Metal Transfer material deposition method was reported. “Response Surface Methodology” optimization procedure was introduced to evaluate the effect of deposition parameters on weld bead characteristics. Investigations have been reported on the development of novel welding torches. The aim of the present manuscript is to give beneficial information about “wire-feed additive manufacturing method” which used for 3D metal part production and evaluate the rapid development of this method at industrial dimension from the viewpoint of net shape manufacturing. © 2025 Elsevier B.V., All rights reserved
Exceedance statistics based on bottom-k-lists (vol 65, pg 5239, 2024)
No full text[Abstract Not Acaileble
Development and evaluation of 177Lu-imatinib: radiolabeling and cell culture studies
No full textTargeted radiopharmaceuticals offer promising approaches for cancer diagnosis and therapy. This study developed freeze-dried kit formulations of Lu-177-Imatinib (IMT) and evaluated their potential efficacy through in vitro studies. Four formulations (F1-F4) containing IMT and chelating agents were prepared and characterized via Fourier transform infrared (FTIR), ultraviolet spectrum (UV), and thermogravimetric analysis (TGA) to confirm complex formation. Biocompatibility was assessed in NIH-3T3 cells using the MTT assay. Radiolabeling with Lu-177 was optimized by varying pH, incubation time, and reactant ratios. Radiochemical purity and stability were analyzed over 7 days using HPLC. Binding affinity and cytotoxicity were evaluated in MCF-7 and NIH-3T3 cells. Spectroscopic analyses confirm successful complex formation. All formulations exhibited >90 % viability in NIH-3T3 cells. Optimal radiolabeling conditions (45 mg IMT-chelator, pH 5, 60 min incubation) yielded >90 % efficiency, with stable radiolabeling for 7 days. The Lu-177-IMT-DOTA (F3) formulation showed significantly higher binding and cytotoxic effects in MCF-7 cells compared to controls. The Lu-177-IMT-DOTA (F3) kit demonstrates high radiolabeling efficiency, stability, and selective in vitro cytotoxicity toward breast cancer cells, supporting its potential as a targeted radiopharmaceutical
Signal-Centric Framework Based on Probability of Detection for Real-Time Reliability of Concrete Damage Inspection
No full textPassive nondestructive testing (NDT) methods allow one to detect damage by the energies emitted from the internal processes. While the test conditions can be controlled and repeatable, obtained data are random, and the probability of detection (PoD) is affected. However, in concrete with complex fracture behavior, factors such as signal attenuation, sensor-damage distance, and test configuration influence the reliability of the test. The conventional practice of proceeding without assessing credibility prevents the ability to determine whether a configuration modification is required, necessitating reassessment. The main objective of this study is to develop a signal-centric framework to enhance the real-time reliability of inspection by investigating the PoD of acoustic emission (AE), a widely used passive NDT method for the real-time monitoring of structures. This study's purpose is to evaluate the mechanical processes and the passive signal responses, emphasizing the detectability of cracking in concrete with two PoD approaches, namely, amplitude- and energy-based PoDs. Additionally, critical signal signatures, namely, signal-to-noise ratio (SNR) and frequency, were pinpointed for their direct influence on the detectability of the crack. With the outcomes obtained, a novel framework, which aims to provide an adaptive evaluation of the PoD of the technique, was suggested to achieve the desired quality in the damage detection of structures
Azerbaycan Devlet Tarım Üniversitesi ve Ege Üniversitesi Ziraat Fakültesi Çift Diploma Programı öğrencilerinin programı ve eğitimi değerlendirmeleri
No full textObjective: The double degree program has launched between Aegean University Faculty of Agriculture (EÜZF) (Türkiye) and Azerbaijan State Agricultural University (ADAU) (Azerbaijan) in 2021. This research aims to provide a general evaluation of the double degree program. Material and Methods: All students in ADAU's dual degree program (312 students) were included. 76.3% of the students (238 people) completed the questionnaire. The survey was conducted in Ganja (Azerbaijan) between October and November 2023. Chi-square, Kruskal Wallis, logistic regression, and factor analysis methods were used to analyze the data. Results: Students have preferred ADAU for reasons such as better education, the existence of a double degree program, international opportunities, the ability to go to Türkiye, seeing agriculture as the profession of the future. 52.6% of students considering a master's degree are desiring to study in Türkiye. Conclusion: Students are generally satisfied with the education they receive. Increasing laboratory and practical studies, increasing the number of elective courses, social-cultural, sports activities, and personal development programs are among the expectations of students from ADAU. © 2025 Elsevier B.V., All rights reserved
Assessment of Brain Volume and Cortical Thickness in People with HIV and Major Depressive Disorder
No full textObjective This study aims to examine neuroanatomical differences associated with depressive symptoms in people with HIV (PWH) by comparing three groups: depressed PWH (PWH Dep+), non-depressed PWH (PWH Dep-), and HIV-negative controls. The primary goal is to explore specific alterations in brain volume and cortical thickness linked to depressive symptomatology in PWH.Methods A total of 61 male participants (28 PWH, 33 controls) underwent psychiatric evaluation and high-resolution structural MRI scanning. Voxel-based morphometry (VBM) and cortical thickness analyses were conducted, with age and education considered as covariates. Participants were classified into PWH Dep+ and PWH Dep- based on depression scales.Results The PWH Dep+ group exhibited increased gray matter volume in the left anterior cingulate cortex and decreased cortical thickness in the left frontal pole compared to controls. In contrast, PWH Dep- participants showed increased cortical thickness in the bilateral postcentral gyrus and posterior cingulate gyrus. Additionally, volume reductions in the middle occipital and middle temporal gyri distinguished PWH Dep+ from PWH Dep-.Conclusions Depression in PWH is associated with structural brain changes, particularly in frontal and occipital regions. Although causality cannot be inferred due to the cross-sectional design, these results may enhance our understanding of the neuropathological mechanisms underlying depression in PWH. The findings should be interpreted with caution, given the relatively small sample size and the exclusion of female participants
Analysis of Magnetic Force Linearity in Magnetic Levitation Systems
No full textThe important parameters of bar magnet configurations, in which the same poles are facing each other, are investigated with a focus on their potential applications in magnetic levitation. The scalar product of the magnetic field and its gradient between magnets is referred to as fz, which is a function for force calculations. The magnitude and linear range of this function are then examined. These parameters are computed for several air gap lengths between the magnets, as well as the height and thickness of the magnets, while keeping the magnet length constant. The calculations are experimentally validated by measuring the magnetic field of a magnet system. The choice of thickness and height of the magnets was found to have critical effects on both linearity and the maximum value of fz within the linear range. The results of this study can be used to guide the selection of magnet dimensions and also to evaluate the factors that can influence the measurements and sensitivity of magnetic levitation systems. © 2025 Elsevier B.V., All rights reserved
Adapting organizational culture scale into healthcare professional education: a scale validity and reliability analysis
No full textBackground: Organizational culture significantly influences the quality of healthcare services and healthcare professional education. Although various scales exist to measure organizational culture at the undergraduate level, validated instruments specifically tailored for healthcare professional education remain scarce. The study aims to validate the adapted scale and provide empirical insights into organizational culture in healthcare professional education. Methods: The adaptation process involved expert consultations to ensure content and face validity, followed by a mixed-methods approach. Quantitative data were collected from 402 students enrolled in the Faculties of Medicine, Dentistry, and Health Sciences during the 2023–2024 academic year. Exploratory and confirmatory factor analyses were performed to examine the scale’s structure. Reliability was assessed using Cronbach’s alpha and McDonald’s omega coefficients. Results: Expert review led to the removal of redundant and unclear items, refining the scale to 30 items across five subscales: Structural Order and Formality, Belonging and Collective Responsibility, Achievement and Performance Orientation, Authority and Hierarchy, and Competition Orientation. The Kaiser–Meyer–Olkin measure (0.846) and Bartlett’s test confirmed sample adequacy. Exploratory factor analysis explained 40% of the total variance. Confirmatory factor analysis showed acceptable model fit indices (?2/df = 3.37, RMSEA = 0.091, CFI = 0.95, TLI = 0.94). The scale demonstrated strong internal consistency (overall McDonald’s ? = 0.878; Cronbach’s ? = 0.874), although lower reliability was noted for Authority and Hierarchy and Competition Orientation subscales. Conclusions: The adapted organizational culture scale is a valid and reliable tool for assessing organizational culture in healthcare professional education. Its use is recommended for tracking cultural changes and supporting strategic educational improvements. Further validation across different institutions and cultural contexts is encouraged to reinforce its generalizability. © 2025 Elsevier B.V., All rights reserved
Optimal Design of Heat Exchanger Systems Using Marathon Runner Algorithm
No full textThe optimal design of heat exchanger systems is critical for enhancing energy efficiency and reducing operational costs in various engineering applications. This paper presents the application of the marathon runner algorithm (MRA), a novel metaheuristic optimization technique, to the design of heat exchanger systems. The MRA mimics the endurance and strategy employed by marathon runners, which is translated into a robust search mechanism for finding global optima. The performance of the proposed algorithm is evaluated against traditional optimization methods through several benchmark heat exchanger design problems. Results demonstrate that the MRA consistently outperforms conventional techniques in terms of solution quality, convergence speed and computational efficiency. The findings suggest that the MRA is a powerful tool for solving complex heat exchanger design problems, providing engineers with a reliable method to achieve optimal configurations. Three operational cases of a shell and tube heat exchanger are desired case studies. The obtained results are compared with those generated by five widely recognized metaheuristic optimization methods. Attained optimal results are comparatively presented through illustrative tables. The results demonstrate that in addressing the thermo-economic model of heat exchanger systems, MRA effectively handles the governing conditions of the case studies and delivers acceptable and promising outcomes. © 2025 Elsevier B.V., All rights reserved
Bir anti-mikrobiyal peptit olan Epinecidin-1’in rasyonel dizayn ile etkinliğinin arttırılması ve maya yüzey gösterimi ile uygulanması
No full textYoğun antibiyotik kullanımına bağlı olarak antibiyotiğe dirençli patojenlerin ortaya çıkması insan sağlığını büyük ölçüde tehlikeye sokmaktadır. Bu nedenle dirençli mikroorganizmalar üzerinde etkili olan yeni ilaçların veya alternatif tedavilerin araştırılması gerekli hale gelmiştir. Antimikrobiyal peptidler (AMP'ler) bu tedaviler arasında öne çıkan alternatiflerden biridir. Hem ökaryotik hem de prokaryotik hücreler tarafından birçok patojene karşı kullanılan ilk ilkel savunma mekanizmasının bir parçasıdır. AMP'ler, geniş spektrumlu aktiviteleri ve geleneksel antibiyotiklere kıyasla farklı etki mekanizmaları nedeniyle yüksek terapötik potansiyele sahiptir. Bununla birlikte, pratik uygulamaları genellikle sınırlı aktiviteleri, konak toksisitesi ve zayıf stabiliteleri nedeniyle engellenir. Bu sınırlamaların üstesinden gelmek için, doğal AMP dizileri protein mühendisliği yaklaşımlarıyla geliştirilebilir. Yüzey görüntüleme teknolojisi, AMP'lerin birincil / ikincil yapılarının çeşitli iyileştirmeler için değiştirilebileceği ve taranabileceği önde gelen yüksek verimli protein mühendisliği stratejilerinden biridir. Tez kapsamında Turuncu Benekli Orfoz'dan elde edilen ve antimikrobiyal, antikanser, yara iyileştirici özellikler dahil olmak üzere geniş bir etki skalasına sahip olan Epinecidin-1 (Epi-1) peptidi üzerinde çalışılmıştır. Rasyonel olarak tasarlanan Epi-1 varyantları rekombinant yöntemle maya hücre yüzeyinde gösterimlenmiştir. Saccharomyces cerevisiae yüzey ekspresyon sisteminde başarılı bir şekilde gösterimlenen ve yüksek ekspresyon seviyesine sahip olan peptidlerin (Epi-1, C3M1, C1M1-E ve C5M3-R) antimikrobiyal aktiviteleri; Enterococcus faecalis (ATCC 29212), Enterococcus faecium (DSM 13590), metisilin dirençli Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Pseudomonas aeruginosa (ATCC 27853) ve Bacillus cereus (ATCC 11778) olmak üzere 6 farklı organizma üzerinde test edilmiştir. Minimum inhibisyon konsantrasyonu (MİK) analiz sonuçlarına göre Epi-1 peptidi ve rasyonel dizayn ile oluşturulan diğer varyantlar test edilen 6 organizmadan 5'inde (P. auroginosa, E. faecium, S. epidermidis, B. cereus, S. aureus) kontrol olarak kullanılan S.cerevisiae'ya oranla daha yüksek antimikrobiyal aktivite gösterdiği tespit edilmiştir. Sitotoksisite deneyleri antimikrobiyal aktiviteden bağımsız olarak maya yüzeyinde gösterimlenen bütün Epi-1 varyantları için gerçekleştirilmiştir. Ekspresyonu doğrulanan peptidlerin adherent HEK293 insan embriyonik böbrek hücre hattı üzerinde farklı konsantrasyonlarda herhangi bir toksik etki göstermediği tespit edilmiştir. Buna ek olarak muamele sonrasında hücre sayısında artış meydana gelmiştir. Bu sebeple maya yüzeyinde gösterimlenen Epi-1 varyantlarının normal hücre hattında hücre proliferasyonunu indüklediği düşünülmektedir. MDA-MB- 231 insan meme kanseri hücre hattı üzerinde yapılan deneylerden elde edilen sonuçlar ise Epi-1'in çeşitli varyantlarının zamana bağımlı (ancak konsantrasyondan bağımsız) şekilde MDA-MB-231 hücre canlılığını etkileyebileceğini düşündürmektedir. Uygulanan Epi-1 varyantları MDA-MB-231 hücre canlılığını üzerinde inhibisyona neden olmuştur. Sonuç olarak rasyonel olarak tasarlanan Epi-1 varyantları maya yüzeyinde başarılı olarak üretilmiştir. Maya yüzeyinde gösterimlenen peptidlerin normal hücre hattı üzerinde toksik olmadığı, kanserli hücre hattı üzerinde etkili olabileceği (antikanser) ve antimikrobiyal aktiviteye sahip olduğu tespit edilmiştir. Üretilen peptidlerin tıp ve kozmetik gibi alanlarda kullanım potansiyelinin olduğu ancak kesin mekanizmalarının anlaşılması ve terapötik uygulamanın belirlenmesi için ileri düzey çalışmaların gerektiği düşünülmektedir.The emergence of antibiotic-resistant pathogens due to intensive antibiotic use greatly endangers human health. For this reason, it has become necessary to investigate new drugs or alternative therapies that have an effect on resistant microorganisms. Antimicrobial peptides (AMPs) are one of the prominent alternatives among these treatments. It is part of the first primitive defense mechanism used by both eukaryotic and prokaryotic cells against many pathogens. AMPs have a high therapeutic potential due to their broad-spectrum activity and different mechanisms of action compared to conventional antibiotics. However, their practical application is often hampered by their limited activity, host toxicity and poor stability. To overcome these limitations, natural AMP sequences can be improved with protein engineering approaches. Surface display technology is one of the leading high-throughput protein engineering strategies in which the primary/secondary structures of AMPs can be modified and scanned for various improvements. Within the scope of the project, Epinecidin-1 (Epi-1) peptide from Orange Spotted Grouper has been studied. It has a wide range of effects, including antimicrobial, anticancer, wound healing properties. Rationally designed Epi-1 variants were displayed on the yeast cell surface. Antimicrobial activities of peptides having a high expression level on Saccharomyces cerevisiae surface expression system (Epi-1, C3M1, C1M1-E and C5M3-R) were tested on 6 different organisms; Enterococcus faecalis (ATCC 29212), Enterococcus faecium (DSM 13590), methicillin-resistant Staphylococcus aureus (ATCC 25923), Staphylococcus epidermidis (ATCC 12228), Pseudomonas aeruginosa (ATCC 27853) and Bacillus cereus (ATCC 11778). According to the results of the minimum inhibition concentration (MIC) analysis, Epi-1 peptide and other variants created by rational design showed higher antimicrobial activity compared to Saccharomyces cerevisiae control on 5 of the 6 tested organisms (P. aeruginosa, E. faecium, P. epidermidis, B. cereus, P. aureus). Cytotoxicity experiments were performed for all Epi-1 variants displayed on the yeast surface, regardless of antimicrobial activity. It was found that the peptides whose expression was confirmed did not exhibit any toxic effects on the adherent HEK293 human embryonic kidney cell line at different concentrations. In addition, an increase in the number of cells occurred after treatment. For this reason, Epi-1 variants displayed on the yeast surface are thought to induce cell proliferation in a normal cell line. Results obtained from experiments conducted on the MDA-MB-231 human breast cancer cell line suggest that various variants of Epi-1 may affect MDA-MB-231 cell viability in a time-dependent (but concentration-independent) manner. Applied Epi-1 variants caused inhibition on MDA-MB-231 cell viability. As a result, rationally designed Epi-1 variants have been successfully expressed and displayed on the yeast surface. It has been found that the peptides displayed on the yeast surface are not toxic to the normal cell line, but might be toxic to a cancer cell line (anticancer effect) and have antimicrobial activity. It is believed that the peptides produced have the potential for use in fields such as medicine and cosmetics, but further studies are required to understand their exact mechanisms and determine the therapeutic routes