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The electrochemical characterization of functionalized isoindolinones
No full textThis study considers the electrochemical and physical properties of six functionalized isoindolinones, synthesized using a facile, green route. The compounds show redox activity at a highly negative potential with quasireversible redox potentials of ≈−2.8 V versus Fc/Fc+, a potential in the region of alkali metal deposition and intercalation. For those molecules with a specific structural motif, the electrochemical behavior is electrochemically quasireversible, attributed to the formation of a carbanion radical stabilized on the carbonyl group. The electrochemical properties of the reversible compounds are assessed, with the lead-performing compound extensively characterized galvanostatically to assess its candidacy for nonaqueous, high-voltage energy storage.</p
Second order channel statistics: an analysis for optimal single-user RIS systems
No full textA key challenge facing reconfigurable intelligent surfaces (RISs) is channel state information acquisition. Passive RISs cannot generate pilot signals or process data, making rapid temporal changes in the channel problematic. Additionally, the impact of spatial changes in RIS channels has not been thoroughly investigated. Therefore, in this work, we use second order statistics to investigate the spatio-temporal behaviour of a single-user (SU) RIS system. Assuming a line-of-sight (LoS) RIS to base station (BS) link, we derive an exact expression for the level crossing rate (LCR) of the RIS link (user equipment (UE)-RIS-BS path) and propose a numerically stable approximation for the LCR of the global UE-BS channel. Each LCR expression attained is then utilised to find the corresponding average fade duration (AFD). The temporal signal-to-noise ratio (SNR) correlation is also derived assuming an LoS RIS-BS link. Assuming a Ricean RIS-BS link, expressions for the spatial correlation matrix of the global channel and the mean SNR loss due to channel ageing are derived. All of the analyses are verified by simulation, and the impact of key system parameters is investigated. We show that the use of an RIS does not significantly amplify changes in the channel
Chemical diversification of polyprenyl quinones for mechanistic studies on menaquinone-binding peptide antibiotics
No full textPolyprenyl quinones, such as ubiquinone and menaquinone, are essential membrane-embedded redox cofactors that are involved in electron transport and found across all domains of life. However, their highly hydrophobic structure, which includes a quinone head-group and long polyprenyl tail, has limited their chemical derivatization for biological studies. Here, we report a versatile synthetic approach for the chemical diversification of natural polyprenyl quinones, enabling the introduction of various reporter groups including fluorophores, quenchers, NMR-active nuclei, and photoaffinity and bioaffinity tags. These functionalized analogues retain their membrane-associating properties and enable new applications in antibiotic discovery. We show that fluorescently labelled menaquinone analogues retain their strong binding affinity to the menaquinone-binding peptide antibiotics lysocin E and lysomeb (MBA2). Incorporation of BODIPY-quinones into vesicles allowed visualization of the peptide-quinone interaction, revealing their effects on membrane integrity and quinone aggregation. This study expands the chemical toolbox for polyprenyl quinones, enabling targeted functionalization of these essential biomolecules and facilitating further exploration of their roles in biological systems.</p
Toward inclusive green human resource management: an identity-based analytical framework
No full textThe concept of green human resource management (HRM) has evolved significantly over the past decades, transitioning from isolated organizational practices to an integral part of strategic HRM systems aimed at environmental sustainability. However, despite the proliferation of green initiatives, employees often feel excluded from these efforts, as firms struggle to embed these practices across all levels of the workforce. We address this inclusivity gap by introducing an identity-based analytical framework for green HRM. By recognizing and integrating multiple social identities, such as self-identity, social identity, and nature-related identity, this framework provides a structured approach to understanding and enhancing inclusive green HRM practices. It highlights key mechanisms, including changing stereotypes, facilitating identity verification and identity complementarity, and building toward the common good. Recognizing the complexities of various diversity dimensions and their intersections, the paper offers a roadmap for organizations to tailor their green HRM practices effectively. Ultimately, this approach bridges the gap between green HRM scholarship and practical implementation, challenging existing limitations in GHRM practices and advancing an inclusive approach to embedding sustainability in the workplace.<br/
Single layer sub-6 GHz leaky dynamic metasurface antenna with wide beam coverage
No full textThis work presents a dynamic metasurface antenna(DMA) for beamforming applications featuring a square complementary electric inductive-capacitive (cELC) resonator as the unit cell. The cELC unit cells are embedded in the top layer of a substrate-integrated waveguide (SIW) in a diagonal arrangement, thereby showing minimum interactions while being placed in a compact topology. P-i-n diodes are mounted on either side of the unit cells to dynamically regulate the radiation response such that a binary distribution is generated for beamforming operation. The proposed design successfully radiates the signal at three specific directions 10°, 35°, and 60°, achieving an impressive broadside beam coverage of 124° (excluding a 9°null) in a single-layer architecture. The antenna has an operating frequency of 5.1 GHz with a realized gain of around 5.6 dBi. The antenna’s performance has been rigorously validated through full-wave simulations and experimental measurements. With its wide beam coverage, efficient beam control and simple hardware architecture, this design holds strong potential for advanced sensing and communication applications.<br/
Hidden costs and unmet supportive care needs among individuals with experience of breast cancer and their carers in the United Kingdom
No full textBackgroundThe impact of cancer transcends physical health, affecting mental wellbeing, financial stability, and ability to perform daily tasks, influencing not only patients but also the broader community.MethodsOnline anonymous surveys (24/01/2023–03/03/2023) were disseminated via charities to individuals treated for breast cancer in the UK and their carers. Multivariable ordered logistic regression models were used to investigate demographic, cancer-related and employment factors associated with physical, wellbeing and financial Quality-of-Life (QoL).Results470 and 136 participants reported primary (PBC) and metastatic (MBC) breast cancer, respectively. 27% PBC and 35% MBC participants reported experience of financial problems. 17% PBC and 47% MBC participants reported trouble fulfilling caring responsibilities at the time of survey completion. For PBC participants, reports of financial problems were associated with difficulties seeking help for physical or wellbeing issues, which were associated with worse physical and wellbeing QoL. Financial problems, and other challenges were more commonly reported among MBC participants. These factors may impact QoL similarly, so there was no evidence of specific explanatory factors for MBC participants.ConclusionsBetter understanding of wider impact of breast cancer could lead to better policy and support. Future clinical trials should incorporate more comprehensive assessment of breast cancer’s wider effects.<br/
A prodrug strategy for sustained release of lactic acid from silicone elastomer vaginal rings
No full textLactic acid is the most abundant organic weak acid in the healthy human vagina and plays a pivotal role in maintaining an acidic vaginal environment protective against exogenous bacteria and viruses. However, in dysbiotic or non-optimal vaginal environments, significantly decreased concentrations of lactobacilli result in reduced lactic acid production, increased vaginal pH, and enhanced risk of sexually transmitted infections (including human immunodeficiency virus), and bacterial vaginosis. Various gel-based products are marketed to administer lactic acid vaginally for the treatment of bacterial vaginosis and non-hormonal contraception, and there is interest in developing vaginal ring products for sustained/controlled release of lactic acid. However, lactic acid is not compatible with the most common addition-cure type of silicone elastomer used to manufacture vaginal rings; the carboxylic acid group inhibits the hydrosilylation reaction used to cure the elastomer system. Here, we report that DL-lactide—a racemic mixture of (R,R)-D-lactide and (S,S)-L-lactide, in which the dilactide molecules are cyclic lactones derived from esterification of two molecules of lactic acid—can be successfully incorporated into and released from addition-cure medical grade silicone elastomer vaginal rings. Following release of lactide from the rings into an aqueous medium, the lactide molecule rapidly hydrolyses to produce only lactic acid. We demonstrate that lactic acid (i) is formed f release of lactide from the rings; (ii) inhibits sperm motility, (iii) inhibits replication of HIV-1 and HSV-2, and (iv) is active against Gardnerella vaginalis (one of the causative organisms responsible for bacterial vaginosis) but not lactobacillus (associated with optimal human vaginal health). The results support the inclusion of lactide as a lactic acid prodrug in next-generation multipurpose contraceptive silicone elastomer vaginal rings.<br/
Microneedles from shape-preserving crosslinked poly(vinyl alcohol) hydrogels: minimising interference in transdermal proteomics
No full textHydrogel-forming microneedle array patches (HFMAPs) enable minimally invasive interstitial fluid (ISF) sampling for biomarker detection. However, optimising their formulation to enhance biomarker recovery and minimise analytical interference while maintaining mechanical properties remains a challenge. This study presents interference-free HFMAPs fabricated from shape-preserving polyvinyl alcohol and polyvinyl pyrrolidone (PVA-PVP) hydrogel. Two formulations are developed with PVA-PVP without chitosan (PP) and with chitosan (PPChi) using micromoulding and evaluated for mechanical strength, insertion efficiency, ISF absorption, and biomarker recovery. The impact of washing to remove interference and chitosan modification on IgG sampling is assessed ex vivo, while in vivo studies measure ISF uptake and skin response. Both formulations exhibit sufficient mechanical strength for insertion, with washed patches maintaining tip sharpness despite minor shrinkage. Formulated HFMAPs absorb over 5 µL of ISF and facilitate quantifiable IgG detection ex vivo, whereas chitosan-modified patches reduce IgG recovery due to biomarker-hydrogel interactions. In vivo, all formulations absorb over 1.5 µL of ISF within 2 h, obtaining sufficient samples for subsequent analysis. Proteomic study reveale 50 to 200 proteins, with chitosan affecting abundance but not the total number detected. These findings support HFMAPs as a promising tool for non-invasive transdermal sampling of protein biomarkers, enabling subsequent proteomic analysis.<br/
Prompt optimization with two gradients for classification in large language models
No full textLarge language models (LLMs) generally perform well in common tasks, yet are often susceptible to errors in sophisticated natural language processing (NLP) on classification applications. Prompt engineering has emerged as a strategy to enhance their performance. Despite the effort required for manual prompt optimization, recent advancements highlight the need for automation to reduce human involvement. We introduced the PO2G (prompt optimization with two gradients) framework to improve the efficiency of optimizing prompts for classification tasks. PO2G demonstrates improvement in efficiency, reaching almost 89% accuracy after just three iterations, whereas ProTeGi requires six iterations to achieve a comparable level. We evaluated PO2G and ProTeGi on a benchmark of nine NLP tasks, three tasks from the original ProTeGi study, and six non-domain-specific tasks. We also evaluated both frameworks on seven legal-domain classification tasks. These results provide broader insights into the efficiency and effectiveness of prompt optimization frameworks for classification across diverse NLP scenarios.<br/
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/