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Dünyaya açılmak için sahip olunması gereken beceriler: kütüphanecilerin küreselleşme yolculuğu
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Evaluation of the Antimicrobial Activity and Cytotoxicity of Rhaponticoides Iconiensis Seed Extract
No full textThe goal of this study is to evaluate the antimicrobial and cytotoxic activities of aqueous extract from Rhaponticoides iconiensis seed. The Soxhlet extraction method was used to extract the seed in distilled water. It was tested for antimicrobial activities against pathogenic bacteria Escherichia coli using the disc diffusion method. Additionally, the cytotoxic activity of the seed extract on the MCF7 breast cancer cell line was evaluated by MTT (3-(4,5-dimethylthiazol2-yl)-2,5-diphenyltetrazolium bromide) assay. R. iconiensis showed strong antibacterial activity against Escherichia coli compared to Cefotaxime antimicrobial agents. Additionally, an effective in vitro cytotoxic activity against the MCF7 is observed (p0.01). The present study is the first report of endemic Rhaponticoides iconiensis seeds exhibiting potential antimicrobial activity and cytotoxicity, and it requires further investigation and characterization. These findings may be applied as a guideline for selecting Turkish medicinal plant species for further pharmacological and phytochemical studies. © 2025, Istanbul Medipol University. All rights reserved.Bayrampasa Science Cente
I See Sick People: Beliefs About Sensory Detection of Infectious Disease Are Largely Consistent Across Cultures
No full textM. Astobiza, Anibal/0000-0003-1399-5388; Marcu, Gabriela Mariana/0000-0003-2508-3749; Viciana Asensio, Hugo/0000-0002-4569-3635;Identifying cues to contagious disease is critical for effectively tracking and defending against interpersonal infection threats. People hold lay beliefs about the types of sensory information most relevant for identifying whether others are sick with transmissible illnesses. Are these beliefs universal, or do they vary along cultural and ecological dimensions? Participants in 58 countries (N = 19,217) judged how effective, and how likely they were to use, cues involving each of the five major sensory modalities in an imagined social interaction during a flu outbreak. Belief patterns were strongly consistent across countries (sight > audition > touch > smell > taste), suggesting a largely universal conceptualization of the role of sensory information for interpersonal respiratory disease detection. Results also support a safe senses hypothesis, with perceivers reporting that they would use senses that function at a distance-and thus reduce pathogen transmission risk-more than would be expected given participants' beliefs as to the efficacy of these senses for disease detection. Where societal variation did emerge, it was captured by a cohesive set of socio-ecological factors, including human development, latitude, pathogen prevalence, and population density. Together, these findings reveal a shared lens through which contagious respiratory disease is assessed, one that prioritizes minimizing risk to perceivers, and may offer leverage for designing interventions to improve public health.This work was supported by the National Science Foundation (grant 2134796, PI: Ackerman). T.S. benefited from support by the Templeton Religion Trust/Issachar Fund project "Science and Religion: An Evolutionary Perspective" (grant 59972) while this research was conducted. In Uganda, G.A. was supported by the Global Challenges Research Grant (AH/S004025/1). In Mexico, G. P-L. received partial support from Metropolitan Autonomous University (UAM) institutional fund, as well as from the Humanities, Sciences, and Technologies Mexican Council (CONAHCYT, grant CAR 273553). In Czechia, JH and SK were supported by Czech Science Foundation (GA.CR 24-10955S). We greatly appreciate the contributions of Ketika Garg, Tuire Korvuo, Irem Kuyucu, Ursula Serdarevich, and Ayushi Shukla to the project.National Science Foundation [2134796]; Templeton Religion Trust/Issachar Fund project "Science and Religion: An Evolutionary Perspective" [59972]; Global Challenges Research Grant [AH/S004025/1]; Metropolitan Autonomous University (UAM) institutional fund [CAR 273553]; Czech Science Foundation [GA.CR 24-10955S
Qubo Formulations and Characterization of Penalty Parameters for the Multi-Knapsack Problem
No full textThe Multi-Knapsack Problem (MKP) is a fundamental challenge in operations research and combinatorial optimization. Quantum computing introduces new possibilities for solving MKP using Quadratic Unconstrained Binary Optimization (QUBO) models. However, a key challenge in QUBO formulations is the selection of penalty parameters, which directly influence solution feasibility and algorithm performance. In this work, we develop QUBO formulations for two MKP variants-the Multidimensional Knapsack Problem (MDKP) and the Multiple Knapsack Problem (MUKP)-and provide an algebraic characterization of their penalty parameters. We systematically evaluate their impact through quantum simulation experiments and compare the performance of the two leading quantum optimization approaches: Quantum Approximate Optimization Algorithm (QAOA) and quantum annealing, alongside a state-of-the-art classical solver. Our results indicate that while classical solvers remain superior, careful tuning of penalty parameters has a strong impact on quantum optimization outcomes. QAOA is highly sensitive to parameter choices, whereas quantum annealing produces more stable results on small to mid-sized instances. Further, our results reveal that MDKP instances can maintain feasibility at penalty values below theoretical bounds, while MUKP instances show greater sensitivity to penalty reductions. Finally, we outline directions for future research in solving MKP, including adaptive penalty parameter tuning, hybrid quantum-classical approaches, and practical optimization strategies for QAOA, as well as real-hardware evaluations.Scientific and Technological Research Council of Turkiye (TUBITAK)Evren Guney acknowledges the support of the Scientific and Technological Research Council of Turkiye (TUBITAK), which contributed to the development of this researc
Effect of Reinforcement Amount on the Microstructural and Mechanical Properties of Mechanically Alloyed Graphene Nanoplatelet Reinforced Al-3.5 Wt% Cu Composites
No full textIn this study, various amounts (0.25, 0.5, 0.75, 1, and 2 wt%.) of graphene nanoplatelets (GNPs) reinforced Al-3.5 wt% Cu metal matrix composites were produced using powder metallurgy processes consisted mechanical alloying and pressureless sintering. To compare the properties of the sintered composites, as-blended and 4 h mechanically alloyed powders were sintered to yield Al-3.5 wt% Cu matrix alloys. The microstructural, thermal and mechanical properties were examined using relevant characterization techniques. The formation of Al2Cu phase was detected at all XRD patterns of the sintered samples other than matrix and reinforcement phases. Mechanically alloyed powders exhibit the equiaxed particle morphology compared to the as-blended ones, their mechanical properties were found better than as-blended and sintered samples. Additionally, mechanical alloying led to the dispersion of GNP reinforcements into the AlCu matrix. The highest hardness value (around 153 HV) was obtained for 2 wt% GNP reinforced composite. The highest wear resistance was recorded for 1 wt% GNP reinforced composite with 2.07 +/- 0.2 mm(3)/N.mx10(-3) wear rate. Additionally, composites' compressive strength improved with adding 1 wt% GNP (similar to 68.5 MPa). The good dispersion of the optimum amount of GNP's via mechanical alloying provide to obtain preferable mechanical properties.Istanbul Technical University Scientific Research Projects Department [MGA-2023-44054]The authors thank to Istanbul Technical University Scientific Research Projects Department for supporting this study with the project number of MGA-2023-44054. The authors thank to Prof. Dr. Hueseyin Cimenoglu, Dr. Faiz Muhaffel, Assoc. Prof. Dr. Nazli Akcamli-Kaya and M.Sc. Berk Senyurt for their helps during mechanical and thermal tests
Investigating the Appropriateness of a Course Evaluation Model: Preservice Teachers’ Flipped Learning Experience
No full textParlett and Hamilton’s (1972) Illuminative Evaluation Model (IEM) was adopted to research course evaluation in flipped learning environments. An integrated data set, including teaching videos, interviews from 17 preservice teachers, and course materials, was collected and analyzed in an educational sciences course. Both quantitative and qualitative data showed that this model, within its learning milieu and instructional systems aspects, had the potential to be a suitable method for instructors to evaluate the quality of their flipped courses. These relationships between the learning milieu and instructional systems provide evidence of the complexity of evaluation. This study demonstrates how the IEM helps uncover the design of a flipped educational sciences course and offers a suitable model for flipped course evaluation. Finally, the implications of this study for general instructional design are discussed
The Impact of Organizational Gossip on Affective Organizational Commitment, Feelings of Loneliness, and Turnover Intention: a Mixed Methods Study
No full textThis study examines the impact of organizational gossip on workplace outcomes, including affective organizational commitment, loneliness, and turnover intention, with a focus on differences between the public and private sectors. Using a mixed-methods approach, the research combines qualitative and quantitative data from surveys conducted with Turkish citizen partners and in-depth interviews with employees in both sectors. The findings reveal that positive gossip enhances social bonds and commitment, while negative gossip leads to loneliness and increased turnover intention, especially in the private sector where job insecurity is higher. The study introduces an integrated framework linking gossip dynamics to organizational processes. Practical implications suggest that managers should address negative gossip while promoting positive gossip to strengthen workplace relationships. This study highlights the dual role of gossip in shaping employee experiences and retention strategies
General Principles of Transitional Justice and the Turkish Context
No full textThis paper was presented in the international conference on "Transitional justice in the MENA Region: Challenges and Opportunities" organized by EuroMed and Human Rights Association on February 8-9 2025 in Istanbul. The paper address how the fundamental principles of transitional justice such as legal accountability, truth-telling and the guarantees of non-repetition be applied effectively in Turkey's current political and social climate
Sürücüsüz Geleceğe Doğru: Otonom Araçlara Yönelik Tüketici Tutumları Üzerine Bir Araştırma
No full textDijitalleşme ile gelişen otomasyon teknolojisi, günümüzde neredeyse her alanda kullanılmakta, günlük hayatının vazgeçilmez bir parçası haline gelmektedir. Otomasyon teknolojisinin en yeni uygulamalarından biri olan otonom araçlar, ulaşım sistemini temelden değiştirme potansiyeline sahip bir teknolojidir. Otomotiv sektörünün teknoloji ile geçirdiği bu değişim, insanların gerçekleştirdiği sürüş deneyimini otomatikleştirmektedir. Bu çalışmanın amacı otonom araçlara yönelik tutumları inceleyerek, otonom araçların benimsenmesini kolaylaştıran ve zorlaştıran unsurları ortaya çıkarmaktır. Bu kapsamda gerçekleştirilen derinlemesine görüşmelerden elde edilen veriler içerik analizi ile incelenmiş, temalar ortaya çıkarılmıştır. Çalışma sonuçlarına göre otonom araçları benimsemeyi kolaylaştıran faktörler algılanan fayda (çevresel, sosyal, duygusal, toplumsal), algılanan kullanım kolaylığı ve kullanışlılık, kişilik özellikleri ve hayat tarzı, ilgilenim, görünürlük ve yaygınlaşma, denenebilirlik ve yeniliktir. Otonom araçları benimsemeyi zorlaştıran faktörler ise veri gizliliği ve teknoloji endişesi, yüksek fiyat algısı, düşük algılanan kullanım keyfi, güven eksikliği ve belirsizlik olarak ortaya çıkarılmıştır