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Seismic response of post-tensioned reinforced concrete beams
No full textPost-tensioning can be used in reinforced concrete beams of long-span moment-resisting frame systems. Such frames are designed using the structural behavior factors given for conventional reinforced concrete structures under the assumption of similar ductility levels. In this study, post-tensioned beams were experimentally investigated to examine their expected seismic behavior. For this purpose, an exterior post-tensioned beam-to-column joint was selected from a code-compliant designed prototype frame building to produce 1:2 scaled specimens. The key test variables were the presence of prestressing and the ratio of mild steel reinforcement. Accordingly, the base shear-lateral displacement, moment-curvature, crack width, dissipated energy, and stiffness degradation relations were obtained. Also, nonlinear finite element analyses were performed to simulate the behavior of the test specimens, consequently, a reasonable agreement between the numerical model and test results was observed upon selecting the steel cyclic model damage parameters appropriately. Then, the required amount of longitudinal rebar for target ductility was suggested through the parametric study calibrated with the experimental outputs of post-tensioned members. Apart from those, the section analysis procedure was followed to propose minimum mild steel ratio for bonded post-tensioned beams
Study of proton–nucleus interactions in the DsTau/NA65 experiment at the CERN-SPS
Get PDFThe DsTau(NA65) experiment at CERN was proposed to measure an inclusive differential cross-section of Ds production with decay to tau lepton and tau neutrino in p–A interactions. The DsTau detector is based on the nuclear emulsion technique, which provides excellent spatial resolution for detecting short-lived particles like charmed hadrons. This paper presents the first results of the analysis of the pilot-run (2018 run) data and reports the accuracy of the proton interaction vertex reconstruction. High precision in vertex reconstruction enables detailed measurement of proton interactions, even in environments with high track density. The measured data has been compared with several Monte Carlo event generators in terms of multiplicity and angular distribution of charged particles. The multiplicity distribution obtained in p–W interactions is tested for KNO-G scaling and is found to be nearly consistent. The interaction length of protons in tungsten is measured to be 93.7±2.6mm. The results presented in this study can be used to validate event generators of p–A interactions
A framework for selection of promising CCUS value chains in the Baltic and Mediterranean regions: CCUS ZEN project study
Get PDFBeyond behavior: Understanding the role of values and personality on pedestrian behaviors
No full textUnderstanding pedestrian behaviors is crucial due to their responsibility for road safety outcomes. Young road users are the most vulnerable group regarding road traffic crashes. This study explores, for the first time in literature, the moderating effect of personality on the relationship between values and pedestrian behaviors among young adults using two major theories in psychology research, The Big Five Personality Model and Schwartz Value Theory. A sample of 389 young adults (Female = 261; Mage = 22.12; SD = 1.89) completed a set of questionnaires. Moderation analyses revealed that conscientiousness and neuroticism emerged as significant moderators. Specifically, increased self-enhancement is associated with more violations at low levels of conscientiousness. Conversely, a low level of conscientiousness, accompanied by increased self-enhancement and openness to change values, is associated with decreased aberrant pedestrian behaviors among young adults. High neuroticism, accompanied by increased openness to change and self-transcendence, is associated with decreased aggressive behaviors. Increased conservation is associated with higher positive behaviors at low levels of neuroticism, while higher self-transcendence is associated with fewer positive behaviors at high levels of neuroticism. The results highlight the interaction between values and personality in influencing pedestrian behaviors, which could be used in pedestrian-specific interventions and educational programs to reduce the unsafe behaviors of pedestrians. The findings are presented in detail and discussed in the context of the relevant literature
Rapid bacterial detection through microfluidic integration with a glucometer
No full textWe present a novel approach for sensitive and portable detection of pathogenic bacteria, which is crucial for household and clinical practice. Our method employs immunoliposomes, antibodies, and microchip to detect specific pathogens quantitatively. Gold and metal metal–organic nanoparticles and liposomes were characterized using high-resolution techniques like TEM and SEM. Utilizing a commercial, personal glucose meter (PGM), we initially detected released glucose from antibody-modified liposomes and microchips with MOF-NPs. Detection on the microchip was achieved within 30 min, while the PGM analysis took only one minute for targeted bacteria, yielding glucose signals of 66 mg/dL and 69 mg/dL, respectively. Serial dilutions with group A-Streptococcus pyogenes (GAS) (1.4 × 10^4–1.4 × 10^8 CFU/mL) demonstrated quantitative measurement applicability. This innovative approach and a portable PGM hold promise for various industries, including physician labs, hospitals, and households
ABD VE ALMANYA'DAKİ ÇİNLİ VE JAPON GÖÇMENLER: EĞİTİM, İŞ VE SAĞLIK KONULARINA İLİŞKİN KARŞILAŞTIRMALI BİR PERSPEKTİF
No full textThis study examines the migration and integration of Chinese and Japanese communities into the United States of America (USA) and Germany, offering a comparative analysis of immigration policies and societal dynamics in both countries. Given that these groups are prominent ethnic communities and play a pivotal role in the labor force of both nations, their significance as the focus of this research becomes evident. The study investigates how civil rights movement in the USA during the 1960s opened new opportunities for Chinese and Japanese individuals, improving their access to education, employment, and healthcare. Similarly, it explores the evolution of Germany's immigration laws, which shifted after the 1990s, allowing greater inclusion of skilled immigrants, including Chinese and Japanese professionals. The research underscores the historical ties between these ethnic communities and their host countries, analyzing why they have been drawn to these destinations despite enduring challenges. While the USA has long embraced multiculturalism, Germany's transition to a more immigration-friendly policy is a relatively recent phenomenon. By examining the integration processes, the study provides a nuanced understanding of the similarities and differences in how these two countries accommodate and utilize the talents of Chinese and Japanese migrants. Ultimately, this work sheds light on broader implications for immigration policy and the socio-economic impact of these communities in multicultural societies.Bu çalışma, Çinli ve Japon toplulukların Amerika Birleşik Devletleri (ABD) ve Almanya'ya göçlerini ve bu ülkelerdeki entegrasyon süreçlerini inceleyerek, her iki ülkenin göç politikaları ve toplumsal dinamikleri üzerine karşılaştırmalı bir analiz sunmaktadır. Bu toplulukların, her iki ülkenin iş gücünde önemli bir rol oynayan belirgin etnik gruplar olmaları, bu araştırmanın odağı olarak seçilmelerinin anlamını açıkça ortaya koymaktadır. Çalışma, 1960'larda ABD'de gerçekleşen sivil haklar hareketlerinin, Çinli ve Japon göçmenler için eğitim, istihdam ve sağlık hizmetlerine erişimde nasıl yeni fırsatlar yarattığını incelemektedir. Benzer şekilde, Almanya'nın göç yasalarının 1990'lar sonrasında geçirdiği değişimi ve bu sürecin nitelikli göçmenlerin, özellikle Çinli ve Japon işgücünün entegrasyonunu nasıl kolaylaştırdığını ele almaktadır. Araştırma, bu etnik toplulukların ev sahibi ülkeleriyle olan tarihsel bağlarını vurgulayarak, karşılaştıkları zorluklara rağmen neden bu ülkeleri tercih ettiklerini analiz etmektedir. ABD’nin uzun zamandır çok kültürlülüğü benimsemiş bir ülke olması, Almanya’nın ise göçmenlere yönelik daha kapsayıcı politikalara geçişinin nispeten yeni bir gelişme olması, çalışma kapsamında ayrıntılı bir şekilde incelenmektedir. Entegrasyon süreçlerini inceleyerek iki ülkenin Çinli ve Japon göçmenlerin yeteneklerini nasıl değerlendirdiğine dair benzerlikler ve farklılıklar derinlemesine incelenmiştir. Sonuç olarak, göç politikaları ve bu toplulukların çok kültürlü toplumlar üzerindeki sosyo-ekonomik etkileri üzerine daha geniş perspektifler sunulmaktadır.M.S. - Master of Scienc
Comparative Aerodynamic Analysis and Parallel Performance of 2D CFD Simulations of a VAWT Using Sliding Mesh Interface Method
No full textWith rapid advancements in computer hardware and numerical modeling methods, Computational Fluid Dynamics (CFD) has gained prominence in simulating complex flows. As parallel computation becomes an industry standard, the computational efficiency of simulations has become critical. The flow around a Vertical Axis Wind Turbine (VAWT), characterized by complex dynamics and challenging rotating geometry, serves as an intriguing case for CFD studies. This study employs the open-source CFD solvers SU2 and OpenFOAM to simulate the incompressible, unsteady, and turbulent flow around an H-type Darrieus VAWT in two dimensions. Spatial and temporal discretization parameters are examined to balance computational cost and accuracy, revealing notable effects on power predictions. Simulations conducted under identical conditions allow for a comparison of the predictions and parallel performances of SU2 and OpenFOAM across three distinct tip speed ratios (TSRs). The findings show that discretization parameters behave differently at various TSRs. While power predictions from SU2 and OpenFOAM generally align with experimental data and with each other, discrepancies arise at lower TSRs, with thrust predictions showing better consistency. Although OpenFOAM provides a faster solution across all parallel configurations, SU2 demonstrates superior parallel scalability, achieving higher speedup and efficiency
A reappraisal of cell cycle phase enrichment in synchronized estrogen receptor-positive cell models derived from breast adenocarcinomas
Get PDF17β-estradiol (E2), the main circulating estrogen hormone, is a critical signaling factor for the growth, differentiation, and function of breast epithelial cells. The effects of E2 on the breast tissue are primarily mediated by the estrogen receptor α (ERα). Deregulation of the E2-ERα signaling contributes to the initiation/progression of breast cancer and resistance to treatments. Cell lines from breast adenocarcinomas as in vitro model systems provide invaluable insight into cellular events, drug discovery, and drug resistance. Among ERα-synthesizing cell lines, MCF7 and T47D cells are widely used to elucidate cell cycle phase-specific molecular events that coordinate cellular proliferation mediated by E2-ERα. Due to variable results in generating phase-enriched populations with various approaches, we wanted to reassess cell cycle synchronization-coupled phase enrichment with charcoal dextran-treated fetal bovine serum, CD-FBS, as an effective hormone withdrawal approach, alone or in combination with excess thymidine, as a DNA replication inhibitor, and/or nocodazole, a microtubule poison, in MCF7 and T47D cells. We find that hormone withdrawal synchronizes both MCF7 and T47D cells at the G0/G1 phase. Supplementation of CD-FBS with E2 enriches the S phase population. E2 with nocodazole and nocodazole-coupled mitotic shake-off augments the G2/M phase population of MCF7 cells. However, the double thymidine block approach with nocodazole or nocodazole-coupled mitotic shake-off is more effective in enriching S and G2/M phase populations of T47D cells. Our results highlight the differential efficacy of synchronization approaches in MCF7 and T47D cells that could provide a framework for cell cycle-specific applications in breast cancer research
Moda sektöründe kurumsal geriletme: tehlikeli kimyasalların kullanımının ortadan kaldırılması
No full textThe textile industry is one of the most pollutant industries and has crucial negative impacts on people and the planet due to hazardous chemicals. This research aims to reveal the actors and their institutional disruption work towards eliminating those harmful chemicals in the textile production processes in Türkiye. A qualitative research design was adopted and 24 interviews were conducted with key players in the field. It is analyzed that brands are the main actors and their requirements from their value chain partners, especially audits and training, play a crucial role in dislodging the embedded practice of using hazardous chemicals in textile production. Their strategies and targets are backed by the laws and regulations, NGO campaigns and remarks, and demands of end users. Manufacturers, chemical producers, standard-setting organizations and initiatives, intermediary buying agents, service providers, and technology developers were identified as other key actors, and their institutional disruption works were underlined. Gender-related issues were also investigated in the scope of this study. This research contributes to the institutional disruption literature in settings where sustainability is a crucial aspect and paves the way for future research towards the institutional creation work regarding the usage of hazardous chemicals.Tekstil endüstrisi en kirletici endüstrilerden biridir ve kullanılan tehlikeli kimyasallar nedeniyle insanlar ve gezegen üzerinde önemli olumsuz etkileri vardır. Bu araştırma, Türkiye'deki tekstil üretim süreçlerinde kullanılan zararlı kimyasalların ortadan kaldırılmasına yönelik aktörleri ve kurumsal geriletme kapsamındaki işleri ortaya çıkarmayı amaçlamaktadır. Nitel bir araştırma tasarımı benimsenmiş ve alandaki kilit aktörlerle 24 görüşme yapılmıştır. Bu çalışmada, markaların ana aktörler olduğu ve değer zinciri ortaklarından taleplerinin, özellikle denetimlerin ve eğitimlerin, tekstil üretiminde zararlı kimyasalların kullanımına ilişkin yerleşik uygulamanın ortadan kaldırılmasında önemli bir rol oynadığı analiz edilmiştir. Markaların stratejileri ve hedefleri; yasalar ve yönetmelikler, STK etkinlikleri ve açıklamaları ve son kullanıcıların talepleri ile desteklenmektedir. Üreticiler, kimyasal üreticiler, standart belirleyici kuruluşlar, aracı satın alma kuruluşları, hizmet sağlayıcılar ve teknoloji geliştiriciler diğer kilit aktörler olarak belirlenmiş ve onların kurumsal geriletme kapsamındaki çabaları da belirtilmiştir. Cinsiyetle ilgili konular da bu çalışma kapsamında incelenmiştir. Bu araştırma, sürdürülebilirliğin önemli bir unsur olduğu durumlarda kurumsal geriletme literatürüne katkıda bulunmakta ve tehlikeli kimyasalların kullanımına ilişkin kurumsal pratikleri oluşturma çalışmalarına yönelik gelecekteki araştırmaların önünü açmaktadır.M.S. - Master of Scienc
OKUL ÖNCESİ DÖNEM ÇOCUKLARININ REHBERLİ OYUN SIRASINDAKİ DENEYİMLERİ VE SÖYLEMLERİ
No full textThis case study explores children's experiences and discourses during guided play, focusing on design, participation, and play practices. Using Mediated Discourse Analysis, Bourdieu's Theory of Practice, and Sociomaterialism as theoretical frameworks, the study examines how children engage with materials, peers, and adults during guided play. The data were collected through implementing guided play activities in a public preschool and the participants were children aged 60-72 months. The analysis of the data revealed that key design, participation and play practices such as negotiation, testing design elements and building new structures were frequently used by children. The findings contribute to understanding the nexus between key practices by offering insights into the interaction of material and social elements in preschool education, while also highlighting transformative events as moments of learning where these practices intersect. During guided play, children actively use open-ended materials to design artifacts, solve problems, and blend creativity with practical experimentation. Socially, guided play provides environment for collaborative behaviors, active role changes between children, and an acknowledgment of expertise or power. These processes highlight the critical role of guided play in supporting learning and holistic development while emphasizing the material and social dynamics. This thesis study contributes to the growing literature on guided play by offering practical and theoretical implications for preschool education.Bu durum çalışması, tasarım, katılım ve oyun uygulamalarına odaklanarak çocukların rehberli oyun sırasındaki deneyimlerini ve söylemlerini araştırmaktadır. Aracılı Söylem Analizi, Bourdieu'nun Pratik Teorisi ve Sosyomateryalizmi teorik çerçeve olarak kullanan çalışma, çocukların rehberli oyun sırasında materyallerle, akranlarıyla ve yetişkinlerle nasıl etkileşime girdiğini incelemektedir. Veriler, bir devlet anaokulunda rehberli oyun etkinlikleri uygulanarak toplanmıştır ve katılımcılar 60-72 aylık çocuklardır. Verilerin analizi, müzakere, tasarım öğelerini test etme ve yeni yapılar inşa etme gibi temel tasarım, katılım ve oyun pratiklerinin çocuklar tarafından sıklıkla kullanıldığını ortaya koymuştur. Bulgular, okul öncesi eğitimde materyal ve sosyal unsurların etkileşimine dair içgörüler sunarak temel pratikler arasındaki bağın anlaşılmasına katkıda bulunurken, bu pratiklerin kesiştiği öğrenme anları olan dönüştürücü olayları da vurgulamaktadır. Rehberli oyun sırasında çocuklar, eserler tasarlamak, problem çözmek ve yaratıcılıklarını pratik deneylerle harmanlamak için açık uçlu materyalleri aktif olarak kullandılar. Sosyal olarak, rehberli oyun işbirlikçi davranışlar, çocuklar arasında aktif rol değişimleri ve uzmanlık veya gücün kabulü için ortam sağlamaktadır. Bu süreçler, rehberli oyunun öğrenmeyi ve bütünsel gelişimi desteklemedeki kritik rolünü vurgularken, materyal ve sosyal dinamikleri de ön plana çıkarmaktadır. Bu tez çalışması, okul öncesi eğitim için pratik ve teorik çıkarımlar sunarak rehberli oyun literatürüne katkıda bulunmaktadır.Ph.D. - Doctoral ProgramTÜBİTAK - Proje No: 323K03