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What is context anyway? Reflections on the experience of the reproductive health working group in the Arab countries and Turkey
No full textBackground: Contextualizing research involves making connections to the broader environment to understand relationships and relevance. This commentary zooms in on the question of how context matters to knowledge production by reflecting on the experience of the Reproductive Health Working Group in Arab Countries and Turkey (RHWG). Summary: In a region such as the Middle East and North Africa that is living through ongoing wars and crises, the network has paid attention to context in multiple ways: as an object of study, as a way to structure the network itself and as a way to conceptualize research support. From its very beginning in 1988, RHWG focused on the importance of social context to understand reproductive health issues. With time, the network became a capacity-building body supporting researchers working on gender and health in situations in which the context itself (the field or the site of empirical data collection) was being destroyed by crises and wars. Furthermore, context structures network activities, in particular the research workshop. The research workshop brings together scholars from the region in a supportive space to share their work thereby reducing isolation caused by wars and crises. In addition, context is an organizing principle and object of study in and of itself at the workshops. Discussions and interpretations of the research papers involve contextualizing them, that is making connections to relations in its surroundings. Conclusion: We have learned over the years that contextualizing research projects is not simply about putting together a historical and social story alongside the work on reproductive health. Contextualizing means thinking about what the concept of context does. In addition, we have learned that to do contextualized research we need to overcome the isolation of researchers created by wars and borders
Modeling and lumped-element extraction of PCB-based laterally coupled coplanar transformers
No full textIn this paper, we present a comprehensive analysis of concentric and interleaved coplanar transformer models, focusing on key performance parameters such as self-inductance, resistance, mutual inductance, and interwinding capacitance. These parameters are used to develop a lumped-element model that accurately represents the behavior of a coplanar transformer. We propose a universal method based on FEM simulations to extract each parameter value, while the validity of the lumped model is verified by comparisons with measurements obtained from printed circuit board (PCB) transformers and HFSS simulations
Designing blend polymersomes co-loaded with HRH peptide and sphingosine for the treatment of ocular neovascularization
No full textOcular neovascularization threatens millions around the world, and current anti-VEGF drugs could not satisfy the clinical needs. Polymersomes, which could penetrate ocular barriers, have recently gained attention as ocular drug delivery systems. In our previous study, high therapeutic efficiency of HA-Sph polymersomes for ocular neovascularization was demonstrated with sphingosine-associated toxicity towards corneal cells. In this study, we developed a novel blend polymersome system composed of two hyaluronan-based amphiphilic polymers that decreases the final sphingosine concentration. The blend polymersomes were incorporated with a second anti-angiogenic compound (HRH peptide) along with sphingosine and exhibited size, zeta potential, and encapsulation efficiency of 141.3 ± 12.2 nm, −25.8 ± 6.2 mV, and 79.8 ± 6.8 %, respectively. The final blend polymersomes system released 35.2 % HRH peptide over a week and this amount is doubled (70.5 %) via enzymatic degradation. Notably, we found that HRH-loaded blend polymersomes significantly reduced the proliferation of HUVECs while not impacting the viability of retinal pigment epithelial and corneal cells. Moreover, in vitro tube formation was significantly reduced by using HRH-loaded polymersomes, compared to HRH alone and ranibizumab groups. The overall tube length was reduced by 29.6 % and 38.1 % compared to normal and excess VEGF controls, respectively. We further observed the self-targeting capability of polymersomes through uptake via CD44 receptors on endothelial cells. Overall, this dual-drug-loaded, blend polymersomes system introduces a safer and more effective alternative to previous HA-Sph platforms and presents a promising, non-invasive approach for treating ocular neovascularization
Initial assessment of component sizing and power-split for fuel cell hybrid electric heavy-duty trucks
No full textThis work presents a computationally inexpensive but effective method for an initial assessment of component sizing and power-split for fuel cell hybrid electric heavy-duty trucks. As a first step, the proposed method employs a prototypical longitudinal vehicle model to generate power demand at every instant of a representative drive cycle. Subsequently, six fuel cell and battery sizing combinations, each providing a peak continuous system power of 400 kW, are identified based on drive cycle power demands, commercially available fuel cell sizes, and Department of Energy (DOE) sizing targets. Ultimately, for each sizing combination, a proportional-integral (PI) controller with anti-windup is implemented to split power between the fuel cell and battery. In this study, the controller is tuned to reduce hydrogen consumption while meeting the instantaneous power demand and maintaining the battery state-of-charge (SOC) between 0.3 and 0.7. The results indicate that increasing the fuel cell size up to a certain threshold reduces hydrogen consumption, beyond which the trend reverses due to regenerative braking power limits and SOC sensitivity of the reduced battery size. This study finds that the combination with a 300 kW fuel cell and a 100 kW (50 kWh) battery achieves the lowest hydrogen consumption, yielding a fuel economy of 7.5 miles/kg, and attaining an 8.4% improvement over the least economical sizing combination
Populist uses of history and foreign policy
No full textThis chapter engages with the question of how populist uses of history in the present can theoretically and empirically be studied across global cases in IR. It argues that two conceptual moves are necessary in forging a theoretically driven empirical study of the populist use of history and its relationship to foreign policy. One is the conceptual treatment of historical representations as long-durée myths, that are deployed by populist actors in linking the past with the present, and which possess strong emotive content and pervasiveness across a given society. The other is the theoretical grounding of the study of myths and their repercussions on foreign policy in the treatment of Self/Other relations by constructivist IR theory. The chapter demonstrates these arguments through an empirical study of the use of history in the making of anti-Western foreign policy in the case of Turkey
Exploring the cybercrime potential of LLMs: a focus on phishing and malware generation
No full textLanguage Large Models (LLMs) are revolutionizing various sectors by automating complex tasks, enhancing productivity, and fostering innovation. From generating human-like text to facilitating advanced research, LLMs are increasingly becoming integral to societal advances. However, the same capabilities that make LLMs so valuable also pose significant cybersecurity threats. Malicious actors can exploit these models to create sophisticated phishing emails, deceptive websites, and malware, which could lead to substantial security breaches. In response to these challenges, our paper introduces a comprehensive framework to assess the robustness of six leading LLMs (Gemini API, Gemini Web, GPT-4o API, GPT-4o Web, Llama 3 70B, and Mixtral 8x7B) against both direct and elaborate malicious prompts to generate phishing and malware attacks. This framework not only measures the ability – or the lack thereof – of LLMs to resist being manipulated into performing harmful actions, but also provides insights into enhancing their security features to safeguard against such prompt injection attempts. Our findings reveal that even direct prompt injections can successfully compel all tested LLMs to generate phishing emails, websites, and malware. This issue becomes particularly pronounced with elaborate malicious prompts, which achieve high rates of malicious compliance, especially in scenarios involving phishing. Specifically, models such as Llama 3 70B, Gemini API, and Gemini Web show high compliance in generating convincing phishing content under elaborate instructions, while GPT-4o models (both the API and Web versions) excel in creating phishing webpages even when presented with direct prompts. Finally, local models demonstrate nearly perfect compliance with malware generation prompts, underscoring the critical need for sophisticated detection methods and enhanced security protocols tailored to mitigate such elaborate threats. Our findings contribute to the ongoing discussion about ensuring the ethical use of Artificial Intelligence (AI) technologies, particularly in cybersecurity contexts
Optimizing the cure cycle of aerospace-grade carbon fiber-reinforced epoxy composites through comparative analysis of resin and prepreg cure kinetics
No full textThis study optimized the cure cycle of an aerospace-grade CFRP composite by examining the cure kinetics of a DGEBA-based epoxy resin and its twill weave carbon fiber prepreg. Cure kinetics, analyzed via HP-DSC at 1, 3, 5.6, and 7 bar, showed that increased pressure significantly extended the resin's curing time but not the prepreg's. Model-Free Kinetics analysis performed was accurate for the prepreg but not for the resin. Rheological analyses showed higher initial viscosity in the prepreg, while the resin displayed a sharper rise in complex viscosity during curing. Using prepreg kinetic data, two optimized cure cycles were developed for fabrication at 3 and 7 bars. Thermal and mechanical testing of composites confirmed the effectiveness of the proposed cycles. This study emphasizes prioritizing prepreg-based cure kinetics over resin data to achieve optimal composite fabrication
Propaganda during economic crises: reference point adjustment in economic news
No full textIn the era of democratic backsliding, information management and manipulation have become a central feature of electoral autocracies. Despite many electoral autocracies experiencing deep economic crises, the incumbents were able to hold onto power. This resiliency is puzzling due to the widespread notion of economic crises leading to regime collapse. In this paper, I introduce an understudied information management strategy, which I call reference point adjustment, employed by pro-government media during economic crises. I argue that government-controlled media increases negative reports about foreign economies during domestic economic turmoil to make the local situation seem comparatively better. Leveraging unique media data from Turkey–spanning 700,000 articles and 13.3 million unique sentences from two major newspapers and an online outlet over 2.5 years–and using supervised machine learning, I find a sharp rise (48% increase) in coverage of foreign economy news by pro-government outlets during an economic crisis. I also observe a significant increase in negative foreign economy news exposure (83% increase) within pro-government media compared to opposition counterparts during these times. This research aims to deepen our understanding of authoritarian politics and media behavior and sheds further light on the democratically backsliding regimes’ playbook
Phenylenediamine-derived carbon dots for carbon-based supercapacitors
Get PDFIn the present investigation, multicolor fluorescent carbon dots (CDs) are produced using meta (m-PD), ortho (o-PD), and para (p-PD) phenylenediamine isomers as precursors. These CDs display bright and stable green, yellow, and red fluorescence under ultraviolet light excitation, with variations in photoluminescence emissions attributed to differences in particle size and bandgap. The CDs from o-PD, m-PD, and p-PD are thoroughly characterized using techniques such as UV–vis spectroscopy, fluorescence emission spectroscopy, transmission electron microscopy, a zeta sizer, Fourier Transform Infrared Spectroscopy, and Raman spectroscopy. As electrode materials in a two-electrode system for symmetric supercapacitors, the performance of CDs is examined, revealing that m-PD-derived CDs (m-CDs) exhibit superior electrochemical properties. Specifically, m-CDs achieve a specific capacitance of 72.3 F g−1 at 0.1 A g−1, an energy density of 1.00 Wh kg−1, and a power density of 9.41 kW kg−1. The enhanced performance of m-CDs is attributed to an increase in electropositivity and faster electron mobility associated with smaller particle sizes. This research highlights the potential of utilizing PD-derived CDs to enhance the electrochemical performance of supercapacitors, demonstrating significant advancements in energy storage technology
Sequential testing problem: a follow-up review
No full textThis review aims to provide a comprehensive update on the progress made on the Sequential Testing problem (STP) in the last 20 years after the review, Ünlüyurt (2004) was published. Many studies have provided new theoretical results, extensions of the problem, and new applications. In this review, we pinpoint the main results and discuss the relations between the problems studied. We also provide possible research directions for the problem