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Evolution of iGluR ligand specificity, polyamine regulation, and ion selectivity inferred from a placozoan epsilon receptor
No full textEpsilon ionotropic glutamate receptors (iGluRs) are a recently defined clade of neurotransmitter receptors that are found in all major metazoan lineages that are distinct from α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), kainate, delta, phi (i.e., AKDF) and N-methyl-D-aspartate NMDA receptors. Here, we explore the evolution of iGluRs by generating a broad species-guided phylogeny of eukaryotic iGluRs and a comprehensive phylogeny of placozoan receptors, uncovering marked diversification of epsilon type receptors within Placozoa. Functional characterization of one epsilon receptor from the placozoan species Trichoplax adhaerens, named GluE1αA, reveals sensitivity to glycine, alanine, serine, and valine, but not glutamate. We demonstrate that changing just three amino acids in the ligand binding domain could convert ligand specificity of GluE1αA from glycine to glutamate, also causing nascent sensitivity to AMPA and increased sensitivity to the blocker 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). We also demonstrate that an atypical serine in the pore Q/R/N site confers diminished Ca2+ permeation and sensitivity to polyamine block, imposing similar effects on the human GluA2 receptor, and that a conserved aspartate four amino acids downstream of the Q/R/N site is crucial for polyamine regulation. Thus, key molecular determinants for polyamine regulation are conserved between AKDF and epsilon receptors.</p
From migration to return: the impact of migration on the health and well-being of family members in China
No full textThis thesis explores the multifaceted impact of internal migration on the health and subjective well-being of family members in China, covering various stages of migration, including initial departure, urban settlement, and return migration. Employing panel data and econometric techniques—particularly fixed-effects models, the instrumental variables approach, and sample selection corrections—the thesis addresses key issues such as omitted variable bias and endogenous migration decisions, thereby strengthening causal inference. The empirical chapters examine the effects of parental migration on the physical and psychological health of left-behind children, highlighting the dual influence of parental absence and remittances. The thesis critically assesses the applicability of the Healthy Immigrant Effect within China, analysing the health trajectories of rural-to-urban migrants and addressing sample selection issues using the Heckman correction method. It also investigates the subjective well-being of return migrants compared to non-migrants, emphasising the role of economic reintegration and relative income positions upon return. The thesis concludes that while migration may generate economic benefits, it imposes substantial health and emotional costs. Effective policy interventions should therefore integrate economic support with improved healthcare access, psychological assistance, and targeted social programmes tailored to migrants’ needs at different stages of migration. Acknowledging existing methodological limitations, the thesis recommends future longitudinal studies with richer data sources and econometric techniques to further strengthen causal analyses and inform policy desig
Understanding anxiety: the role of psychological flexibility, intolerance of uncertainty and death anxiety as transdiagnostic mechanisms
No full textAnxiety disorders are among the most common mental health conditions globally and cause significant impairment in psychosocial functioning. Transdiagnostic processes such as psychological flexibility, intolerance of uncertainty and death anxiety have shown to be important in the development and maintenance of anxiety. This thesis aims to explore how these processes operate across populations, and more specifically, among healthcare professionals (HCPs). To explore these processes, a systematic review and empirical study were undertaken. A systematic review and meta-analysis examined the association between psychological flexibility and anxiety. The meta-analysis of 29 studies found a moderate negative association between PF and anxiety, however effect sizes varied by PF measure used, anxiety construct measured and sample size. Alongside this, a cross-sectional, mixed-methods study explored health anxiety among HCPs working in inpatient oncology, neurorehabilitation and mental health acute/psychiatric intensive care units. Psychological flexibility, intolerance of uncertainty and death anxiety were explored as predictors of HA. Quantitative findings found no significant differences between staff groups and HA. Death anxiety and psychological flexibility emerged as significant predictors of HA. Thematic analysis of qualitative data generated three overarching themes: (1) health consciousness; (2) shifting values, perspectives and acceptance; and (3) workplace stressors and coping. These findings contribute to the current literature on transdiagnostic mechanisms in anxiety. The meta-analysis identifies key moderators which may account for the inconsistencies in the literature. Additionally, the empirical study offers novel insights into how transdiagnostic processes are associated with health anxiety among HCPs, and the qualitative findings offer a nuanced understanding of the impact of clinical exposure (e.g. death, illness) on HCPs lifestyle choices and perspectives on life. This thesis may help to inform the development of more targeted interventions and highlights important areas for future research.Keywords: anxiety, anxiety disorders, healthcare workers, health anxiety, psychological flexibility, death anxiety, intolerance of uncertaint
Crowdsourcing remote co-design towards improving the validity and reliability of mHealth application development – a case study on sleep solved: a mHealth app designed virtually with teens
No full textIntroduction: co-design has become a fundamental pillar of formative digital health research. Typically, this approach involves in–person workshops that involve a rich but limited amount of data. Virtually crowdsourcing co-design, however, provides the promise of rapid and vastly increased data. This is a novel, exploratory approach in mHealth design that may appease common health research concerns surrounding reliability and validity, whilst providing swifter feedback to meet product development timelines.Objectives: the objective of this exploratory single case study was to explore the virtual, crowdsourced, co-design of Sleep Solved, an educational mHealth sleep app designed with teens. In doing so, we wished to learn which virtual methods were used to engage teens in the co-design and to explore how these virtual co-design methods can be adapted for large-scale ideation and testing.Methods: we conducted an enquiry-based iterative case study utilising the Bayazit 3-stage model. 85 teens participated over 11 months. Data was thematically analysed over several design iterations.Results: rapid virtual feedback allowed for quick pivots in a short time frame. Four stages of feedback from teens led to iterative changes to scientific information contextualisation and user experience, from lo-fidelity mock-ups through to a coded app beta.Conclusion: the co-design of Sleep Solved exemplified the potential of virtually crowdsourcing teens in mHealth. Key to this evolution will be the ability to leverage big data utilising AI and machine learning approaches to data collation and synthesization, such that meaningful and contextual findings can be applied in line with software development timelines
A framework for fractional matrix programming problems with applications in FBL MU-MIMO
No full textAn efficient framework is conceived for fractional matrix programming (FMP) optimization problems (OPs) namely for minimization and maximization. In each generic OP, either the objective or the constraints are functions of multiple arbitrary continuous-domain fractional functions (FFs). This ensures the framework’s versatility, enabling it to solve a broader range of OPs than classical FMP solvers, like Dinkelbach-based algorithms. Specifically, the generalized Dinkelbach algorithm can only solve multiple-ratio FMP problems. By contrast, our framework solves OPs associated with a sum or product of multiple FFs as the objective or constraint functions. Additionally, our framework provides a single-loop solution, while most FMP solvers require twin-loop algorithms. Many popular performance metrics of wireless communications are FFs. For instance, latency has a fractional structure, and minimizing the sum delay leads to an FMP problem. Moreover, the mean square error (MSE) and energy efficiency (EE) metrics have fractional structures. Thus, optimizing EE-related metrics such as the sum or geometric mean of EEs and enhancing the metrics related to spectral-versus-energy-efficiency tradeoff yield FMP problems. Furthermore, both the signal-to-interference-plus-noise ratio and the channel dispersion are FFs. In this paper, we also develop resource allocation schemes for multi-user multiple-input multiple-output (MU-MIMO) systems, using finite block length (FBL) coding, demonstrating attractive practical applications of FMP by optimizing the aforementioned metrics
The case for the evolution of the All Sciences Journal Classification (ASJC) system
No full textThis Working Paper sets out the case for the modernisation of the All Sciences Journal Classification System (ASJC), with particular emphasis on the classification of journals in the Medicine subject fields.The ASJC was developed by a team at Elsevier Science some 25 years ago and it is widely used on a global basis. However, it has not kept pace with many changes in international academic publishing.These include the growth in multidisciplinary journals; the inclusion of Arts and Humanities, Law and other Social Science subject journals in bibliometric systems; and the diversity of academic publishing vectors, including Books, Theses, Patents and Conference Proceedings. The paper also describes a series of experiments with machine learning and artificial intelligence tools by colleagues in the Elsevier Data Science Teams to assess the merits of automation of classification of journals.Many journals prove difficult to classify with ML/AI tools, and human expert evaluation and judgement is likely to find a continuing role in any future iterations of the ASJC<br/
Practice, reason, and the good: human nature and MacIntyrean business ethics
No full textMacIntyrean business ethics research has focused on the concept of a practice, drawn primarily from After Virtue. MacIntyre later emphasized the need to adopt an account of human nature to provide a better grounding for his earlier social teleology. We consider three implications of incorporating the neo-Aristotelian and Thomistic account of human nature outlined in MacIntyre’s later works for MacIntyrean business ethics research: First, this account enables the MacIntyrean perspective to better ground its focus on practices as a key moral requirement for the organization of work. Second, it provides a better basis for distinguishing productive practices in good order from other business activities lacking the characteristics of a practice. Third, a theory incorporating an account of human nature, particularly MacIntyre’s notion of natural law, is better able to address broader questions in business ethics that are not directly concerned with the structure of work
Short-block polar-coded reverse and direct reconciliation in CV-QKD
No full textContinuous-variable quantum key distribution (CV-QKD) is a promising technique of supporting quantum-safe wireless networks in the emerging 6G era, mapping quantum information onto the amplitude or phase of electromagnetic waves. However, conventional CV-QKD reconciliation methods often assume ideal classical side-information channels, which is an unrealistic scenario in practical deployments. To address this critical challenge, we propose a novel protection scheme integrating Polar and low-density parity-check (LDPC) codes. Specifically, Polar codes safeguard quantum transmissions due to their superior performance for short block lengths, while LDPC codes robustly protect the classical side information exchanged over auxiliary classical channels. We further enhance the CV-QKD performance by harnessing a soft-decision Polar decoding method combined with protocols specifically tailored for reverse reconciliation (RR) and direct reconciliation (DR). In the RR scheme, conceived decoding complexity is strategically distributed: Polar decoding is performed by Alice, and LDPC decoding by Bob, hence significantly reducing the computational demands compared to traditional schemes where both decoding processes are invoked at a single node. Simulation results validate the effectiveness of our approach, demonstrating that Polar codes consistently outperform LDPC codes in quantum transmission scenarios having short block lengths under 512 bits. These findings emphasize the strong potential of Polar coding-assisted CV-QKD in achieving secure and efficient quantum-safe control information transmissions, paving the way for practical implementation in next-generation wireless networks.</p
The impact of the delegated management model of urban piped service delivery on water quality in Kisumu, Kenya
No full textDelegated management (DMM) is a water service delivery model, whereby micro-operators financially and operationally manage underserved areas of a piped network. This post-hoc evaluation aimed to assess the impact of DMM on water safety. Kiosk and household stored water in DMM and matched control areas were tested for microbiological quality, showing comparable, substantial post-collection contamination. DMM increased household piped connections, reducing the need for household water storage and thereby post-collection contamination. However, DMM kiosk users remain exposed to recontaminated water. DMM remains a viable service delivery model, but other strategies are needed to address post-collection contamination of household stored water
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