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How to enhance the ISAC security in cell-free networks?
No full textThis paper investigates a secure cell-free integrated sensing and communication (ISAC) system designed to simultaneously localize a potential eavesdropper (Eve) and ensure secure communication for legitimate user equipment (UEs). Unlike existing solutions that focus primarily on direction estimation, a distributed architecture employs multiple access points (APs) that collaboratively transmit communication signals and omnidirectional sensing signals for localization. We present analytical closed-form expressions for the signal-to-interference-plus-noise ratios (SINRs) at the legitimate UEs and Eve, facilitating a theoretical evaluation of the system's secrecy spectral efficiency (SSE). Furthermore, we derive a tractable closed-form expression for the localization SINR after matched filtering and subsequently develop the corresponding Cramér-Rao lower bound (CRLB) for the received signal strength (RSS)-based localization, which is validated through Monte-Carlo simulations using the GaussNewton method. To optimally enhance the communication security performance and sensing accuracy, we formulate and solve an optimization problem, allocating power subject to a total transmit power and localization SINR constraints. Numerical results demonstrate the effectiveness of the proposed approach, highlighting significant improvements in both the secure communication performance and localization accuracy within cell-free ISAC architectures
Effects of obesity on response to asthma biologic treatment: Longitudinal data from the United Kingdom Severe Asthma Registry
No full textBackground: Obesity is a common co-morbidity associated with poor outcomes in severe asthma.Objective: We aimed to determine whether obesity is associated with an altered response to severe asthma biologic agents.Methods: We analysed data from the UK Severe Asthma Registry, a large UK-wide cohort of patients attending regional severe asthma services. We analysed the change in clinical outcomes between baseline and first annual review visit by body mass index (BMI) category (Healthy Range [18.50-24.99], Overweight [25.00-29.99], Obese [30.00-39.99] and Severely Obese [≥40]), and biologic treatment status.Results: The study cohort comprised 1956 patients, of whom 1477 (75.5%) commenced a biologic agent during follow-up. Baseline Asthma Control Questionnaire-6 (ACQ-6) scores, and rates of exacerbations, emergency department attendances and hospital admissions were higher with increasing BMI category. Biologic treatment was associated with significant additional improvement in ACQ-6, compared to patients not receiving biologics, in overweight, obese and severely obese patients. However the ACQ-6 score following biologic treatment remained significantly different across BMI categories, with the mean score being 1.3 in the healthy weight group and 2.8 in the severely obese group (p < 0.001). Biologic treatment was associated with significant additional reductions in exacerbation rates, in all BMI groups except for the severely obese.Conclusion: Asthma biologic agents appear to have important clinical benefits across the spectrum of BMI. However, because patients with obesity start at a worse baseline with respect to symptoms and exacerbations, they are still more likely to remain uncontrolled following treatment
Oceans tidal energy
No full textTidal energy is an abundant and predictable renewable energy resource making it a unique and valuable contribution to the diversification of energy away from carbon-intensive fossil fuels. The concept is not new, and the earliest uses of tidal energy date back to the neolithic era. The study of tides has been well documented, and due to its predictability, it makes an ideal renewable energy resource. Two dominant forms of tidal energy will be discussed: tidal range/impoundment and tidal stream, and these technologies predominantly use the same physics for energy conversion but have very different approaches and associated opportunities and challenges. The tidal energy sector has a handful of successful demonstration projects that will be highlighted, and there is a pipeline of future projects globally.</p
Designing nature based solutions for the built environment in the future climate: a case study in Barcelona
No full textClimate change poses significant risks to urban areas, particularly the phenomenon of urban heat island (UHI) effect, which exacerbates thermal stress and environmental degradation in densely populated cities. The Climate Change Committee (CCC) has identified rising urban temperatures as a critical challenge, with projections indicating that by 2050, 68% of the global population will reside in urban areas, further increasing vulnerability to extreme heat events. Nature-Based Solutions (NBS) provide a holistic and sustainable alternative, incorporating green infrastructure, vertical greening systems, and natural ecosystems to simultaneously address UHI impacts and enhance urban ecological balance.This study investigates the potential of NBS in mitigating urban heat in Barcelona, a city characterized by its dense urban fabric, Mediterranean climate, and high levels of tourism. The research examines strategies for creating biodiverse urban forests, strengthening green corridors, and reducing UHI effects while advancing sustainable urban development. Employing a research-by-design methodology, this study develops urban forests as a highly sustainable development approach for future climates. The research process consists of three main stages: (1) an evaluation phase, which involves analyzing the site model for projected conditions in 2050, focusing specifically on changes in heatwave patterns. (2) a design phase, where scenarios are developed to enhance the urban environment through nature-based approaches across multiple scales, and (3) a retesting phase, involving simulation-based experiments to evaluate the effectiveness of each design strategy. Simulations compare the environmental impacts of the enhanced nature-based design scenarios, both with and without the inclusion of vegetation. The findings show the importance of developing nature-based solutions in the architecture and planning strategies, as a means of promoting more sustainable and resilient cities in the face of global climate change. The findings of this study underscore the urgency of adopting innovative approaches to urban regeneration that leverage nature-based solutions to enhance the connection between nature, humans, and cities.<br/
Development of a real-time chromogenic film utilising a sensory response scale and biomarker strategy for identifying the rancidity degree of infant formula rice flour
No full textRancidity in infant formula rice flour (IFRF) is a common challenge with measurable impact on the dairy industry development. This study proposed a real-time chromogenic film based on PVA/Schiff’s reagent that targets rancidity. The results demonstrated that the developed ten-point, five-grade sensory scale method exhibited excellent linearity (R2 = 0.998) between the sensory grades and the rank sum of rancid odour intensity. Orthogonal partial least squares discriminant analysis (OPLS-DA) analysis confirmed a positive linear correlation between the contents of IFRF aldehyde marker and the observed rancidity levels. By optimising the film preparation process, the best processing parameters were determined to be 83 ℃, 18 min, and 0.5 Hz for the chromogenic film preparation. Validation using the sensory evaluation showed an identification accuracy exceeding 88.67%. Analysis of authentic samples revealed a higher incidence of rancidity in products manufactured, providing valuable guidance for producers and consumers. Therefore, the chromogenic film method offers a reliable alternative to standard methods for sensory evaluation, quality control, and final product analysis of IFRF.</p
Exploring protein aggregation in biological products: from mechanistic understanding to practical solutions
No full textProteins are vital for the regulation of several cellular functions, including the synthesis of structural components. The change in environmental conditions will impact conformational stability and result in aggregation. Protein aggregation involves different states of proteins, like nonnative, unfolded, and native states, which make them complex processes. The proper understanding of protein aggregation pathways involving the role of thermodynamically unfavoured lag phase, soluble protofibrils triggered polymerization through an exponential phase, and depleted free monomers owing to the saturation phase resulted in the leveling off of the polymerization process. The aggregated therapeutic proteins can induce deleterious immune responses in patients, and control of the aggregation is essential for better therapeutic protein stability and targeting with the help of stable protein structures and function. Protein–protein interactions (PPIs) are important for protein stability, aggregation rate, and solubility, while advanced computational and biophysical methods have been developed to characterize therapeutic protein aggregation better. Hence, an effective strategy for controlling, monitoring, and reproducing protein aggregation propensities of the polypeptide chains is required. An in-depth understanding of protein aggregation mechanisms, characterization, and combat strategies will counter the issues of protein aggregation. It will also reduce the cost of the product, time constraints, stable & effective product availability, and potential immunogenicity
Multi-user key rate optimization for near-field extremely large-scale antenna array communications
No full textExtremely large-scale antenna arrays (ELAA) require near-field spherical wave modeling due to the substantial increase in the number of antennas, which introduces new spatial dimensions to physical layer key generation (PLKG). We investigate multi-user PLKG in near-field environments, where a base station with an ELAA simultaneously generates secret keys with multiple users. We derive an analytical expression for the key rate (KR). By utilizing spatial dimensions of distance and angle in near-field environments, we apply eigenvalue decomposition and singular value decomposition to design precoding matrices to reduce interference among user equipments (UEs) and extract uncorrelated subchannels. Given that the KR is non-convex, we approximate it and optimize the precoding matrix to increase the KR. After precoding design, the KR depends on the transmit power allocated to the subchannels. Two optimization problems are formulated to further optimize transmit power allocation. The first problem focuses on maximizing the sum KR. We apply the Lagrange multiplier method to determine the optimal power allocation variables by searching the Lagrange multiplier. To reduce computational complexity, a supervised feedforward neural network (FNN) is designed to capture the relationship between the power allocation variables and the Lagrange multiplier. The second optimization problem focuses on KR fairness. By introducing a slack variable that is smaller than the KRs of all users, we use the CVX toolbox to find optimal power allocation variables that maximize this slack variable. To further reduce complexity, the Lagrange multiplier method offers an analytical solution for power allocation variables in terms of Lagrange multipliers determined by the slack variable in the high-power case. We employ a bisection algorithm to find the slack variable. Furthermore, we propose an FNN to map transmit power to the slack variable. Simulations demonstrate that the proposed methods efficiently leverage near-field effects for multi-user PLKG, reducing pilot overhead.<br/
Unfortunate electoral designs for postconflict democracies: lessons from Dayton for the Western Balkans
No full textThis paper argues that the combination of electoral and institutional design in Bosnia and Herzegovina (BiH) implemented by the Dayton Peace Agreement (DPA) – while intended to stabilize peace through consociational and territorial powersharing – paradoxically entrenches ethnopolitical divisions rather than fosters transformation. The use of open-list proportional representation (PR) electoral system and the Sainte-Laguë method for allocating legislative seats ensures political visibility of ethnic groups; however, simultaneous provision of reserved seats for politically relevant groups inhibits cross-ethnic political cohesion. As group-based identity politics and an integrative drift favoring majority groups prevails in BiH is often taken as given, this paper suggests that this specific combination of electoral rules and seat allocation hinder both meaningful accommodation and broader integration of minorities in electoral wards, despite emphasizing the need for minority visibility.<br/
Dehusking reduces nutritional and antioxidant quality of Nigerian millet varieties
No full textMillet is a staple food in northern Nigeria, widely consumed in various traditional dishes. However, common processing practices, such as dehusking, may significantly affect its nutritional and antioxidant properties. This study evaluated the antioxidant composition and nutritional value of four millet varieties cultivated in Northern Nigeria, with a focus on the impact of dehusking. Analyses included proximate composition, phytochemical content, antioxidant vitamins, mineral elements, amino acid profile, and antioxidant activities. All millet varieties contained significant amounts of antioxidant compounds, including phenolics, flavonoids, and vitamins, although their concentrations varied due to genetic and environmental influences. Calcium (Ca) was the most abundant macromineral (p < .05), while iron (Fe) was the dominant microelement, and selenium (Se) was present in trace amounts. Dehusking significantly (p < .05) reduced the levels of most nutrients and antioxidants, underscoring the nutritional quality of whole grains. The presence of essential phytochemicals, amino acids, and crude fibre in millet supports its potential role as a functional food ingredient. These findings highlight millet’s nutritional and functional potential as a source of essential nutrients, supporting its use in nutraceutical formulations or as functional food. Preserving the bran layer during processing is crucial to fully leverage millet’s health benefits and maximise its role in promoting human health