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Borrowing constraints and marginal propensity to consume: Role of negative wealth constraint
Get PDFWe develop an analytically tractable model of consumption, savings, and investment with the negative wealth constraint (NWC), where an economic agent can borrow up to a fixed proportion of the present value of labor income. Consumption is strictly concave in wealth, even when labor income is riskless. A tighter NWC leads to a higher marginal propensity to consume (MPC) out of financial wealth. Our model generates MPC magnitudes in the empirically observed range of 20%-60%
Vibration power flow and dynamic interactions in nonlinear mistuned bladed disk system
No full textThis study investigates vibration characteristics and energy transfer in linear and nonlinear mistuned bladed disk system. The power flow analysis (PFA) method is developed to reveal the dynamic interactions and energy distribution patterns. Power flow equations based on a lumped parameter model (LPM) considering the cubic stiffness and dry friction nonlinearities are derived. The harmonic balance (HB) method with the alternating frequency time (AFT) scheme is used to solve analytical solutions of steady-state frequency response of both linear and nonlinear cases. Numerical time marching method is used to obtain reliable time-domain responses for comparisons with analytical solutions. The results show that energy transfer from the blades to the disk is affected by the cubic coupling stiffness, resulting in bending of the second resonance peaks in disk-dominant modes at higher frequencies with out-of-phase motion. The dry friction primarily contributes to reducing vibration amplitudes by dissipating more energy. Mistuning effects on the dynamic interactions between sectors are also investigated, and it is shown that mistuning of blade stiffness causes intense vibration energy localization and uneven energy distribution within the system. It is shown that power flow can serve as an indicator of mistuning conditions. Also, power flow-based indicators such as the Stress Amplification Indicator (SAI) and the tuned Coupling Power Indicator (tCPI) are used to effectively quantify mistuning sensitivity. The effects of single blade mistuning on the dynamics are experimentally investigated, demonstrating that mass and stiffness mistuning induce distinct changes in both natural frequencies and response amplitudes of bladed disk system. These results contribute to better design and performance optimization for the dynamics behaviour of nonlinear bladed disk systems
D‐Optimal Design for Enzymatic Ring‐Opening Polymerization of ε‐Caprolactone: Toward Sustainable Polyester Synthesis Using Biobased Solvents
Get PDFPoly(ε-caprolactone) (PCL) is an ideal model for advancing sustainable polymerization, particularly enzymatic ring-opening polymerization (eROP). Optimizing eROP for PCL can inform greener synthesis strategies for polyesters, supporting circularity and reducing plastic waste. However, the lack of standardized parameters, such as solvent, initiator, enzyme loading, temperature, and monomer concentration, hinders meaningful comparisons across studies. To address this, we applied a systematic design of experiments (DoE) approach, which remains underused in polymer synthesis and, to our knowledge, has not been applied to eROP. Using a D-optimal DoE methodology, we conducted 38 statistically guided experiments varying temperature, enzyme loading, reaction time and monomer concentration. Two biobased hydrophobic solvents, 2-methyltetrahydrofuran (2-MeTHF) and pinacolone, were included as sustainable alternatives to toluene. DoE enabled an efficient screening of multivariate interactions while reducing the number of reactions and associated waste. Performance in biobased solvents, monomer conversion, molar mass dispersity, and dimer byproduct formation was comparable to toluene. This validates greener solvents for eROP and demonstrates the potential of DoE-driven optimization to accelerate environmentally responsible polymer synthesis, minimizing experimental burden and intrinsic waste
Health-related Research on Remote islands in the South Atlantic Ocean: Facilitators and Barriers identified within a scoping review
No full textIntroduction: The objective of this scoping review is to characterise the nature of health-related research in the remote South Atlantic United Kingdom Overseas Territories (UKOTs) and explore facilitators and barriers to research in this context.Methods: A review of the published academic research covering human health in the South Atlantic UKOTs between 1950 to 2025 was carried out on 23rd September 2025. The following databases were searched: CINAHL, Embase, Global Health, Medline, and Global Index Medicus. Data on bibliographical information, study design, country of study, objectives, lead research organisation and collaborators, population group and sample, and health topic were extracted and charted; and unique contextual factors and explicit or implied barriers or facilitators were narratively summarised.Results: The search yielded 179 records, leading to 68 included studies meeting the search criteria. Thirty-eight studies were carried out on Tristan da Cunha, nineteen on St Helena, eight in the Falkland Islands, and three covered multiple territories. Health topics included genetics of disease, dental health, infectious diseases, and non-communicable diseases. Most were descriptive or analytical observational studies, and many were led by researchers from other countries.Discussion: Research has focused extensively on the small Island of Tristan da Cunha. Barriers to research identified included the small population size and resulting close-knit social structures, and a lack of research skills and capacity. Research facilitators included the geographical and social isolation, enabling novel research, although this poses risks of research without explicit benefit to local populations. Collaborations with external institutions and agencies have been successful and highlight future opportunities for research support. There is scope for health-related research that would build skills in local researchers, deliver locally relevant evidence, strengthen collaboration with overseas experts and funders and potentially enable learning on other remote, resource-limited contexts
Physiological oxygen levels reset K+ channel activity in human vascular endothelial cells
Get PDFHuman endothelial cells (EC) play a critical role in vascular homeostasis and their function is influenced by oxygen tension. This study investigates for the first time the effects of long-term adaptation (5 days) of two major EC types to physiological oxygen tension (5kPa) on basal and nitric oxide (NO)-modulated K+ channel activities. Whole-cell patch clamp experiments demonstrate that human umbilical vein EC (HUVEC) exhibit larger basal K+ outward and smaller inward currents under 5kPa O2 compared to standard hyperoxic (18kPa) culture conditions. Outward currents were potentiated by NO only under hyperoxia. Human cerebral microvascular EC (hCMEC/D3) showed larger outward currents under 5kPa O2 which were further potentiated by NO. Pharmacological isolation of different K+ currents using tetraethylammonium, TRAM-34 and apamin revealed differential effects in EC adapted to 5kPa or 18kPa O2. Under 5kPa O2, both cell types show greater contributions of TEA-sensitive currents and in addition hCMEC/D3 cells exhibit higher proportions of TRAM-34 and apamin-sensitive currents under 5kPa O2. In HUVEC, changes in half-activation voltage and hyperpolarized membrane potentials were detected only under hyperoxic conditions following NO exposure, with both cell types exhibiting altered current activation kinetics of outward and inward currents. Notably, expression of KCa3.1, KCa1.1, KCa2.3 and Kir6.1 channels was unaffected by O2, suggesting that changes in whole-cell currents in both EC types were due to channel modulation. Thus, our findings reveal that physiological O2 tension shapes the electrophysiological phenotype of human EC by modulating K+ channel function and NO responsiveness. The novel insights into the modulation of EC K+ channels by O2 has implications for the regulation of vascular tone and design and use of experimental models in vitro for high throughput drug discovery and clinical translation
Ultra-sensitive microwave magnetometry with organic-molecular sensors
Get PDFUltra-sensitive microwave sensing is widely demanded in various fields, ranging from cosmology to microwave quantum technology. Quantum magnetometers based on inorganic solid-state spin systems are promising for this because of their stability and biocompatibility, but the sensitivity is currently limited to a few pT√Hz. Here, by utilizing an enhanced readout scheme with state-of-the-art solid-state maser technology, we develop a robust microwave quantum magnetometer based on spins in organic molecules at ambient conditions. Owing to the maser amplification, the sensitivity of the magnetometer reaches 6.1(2)fT√Hz, which is three orders of magnitude better than that of the inorganic solid-state quantum magnetometers. Heterodyne detection without additional local oscillators improves the bandwidth of the sensors and allows determination of the field frequency. The scheme can be extended to other solid-state spin systems without complicated control pulses and thus enables applications, such as electron spin resonance spectroscopy, dark matter searches, and astronomical observations
Exploring Stakeholder Acceptance of Workplace Personalisation
No full textPersonalisation in the workplace may be used to support workers by simplifying tasks or reducing workload but requires the collection of personal data, and this raises concerns over privacy and possible discrimination if applied indiscriminately. The study explored the factors associated with acceptance of three types of workplace personalisation system (Suggester, Swappers and Controller, within-subjects) and two personal data types (Heart Rate, Performance, between-subjects) by presenting vignettes using an online experimental platform (Prolific.com) and capturing respondents’ (n=204) attitudes using recognised acceptance questionnaires (e.g. the Advanced Transport Telematics Acceptance Assessment, ATTAA). Results show acceptance is influenced by the type of personalisation system, particularly when physiological (heart rate) data is used, with ‘swapper’ systems receiving the highest ratings for ‘usefulness’ and ‘satisfying’ (interpreted as higher acceptance) compared to suggesters and controllers. Acceptance ratings were not significantly different between personalisation types when performance data were used. The affinity for technology (AFT) and need for cognition (NFC) scales were used to categorise participant characteristics, but only revealed significant differences associated with NFC and usefulness – most notably when using performance data. Overall, the results support the need to consider the type of intervention and the type/amount of personal data required when designing and implementing workplace personalisation systems and highlight a particular need for caution when physiological data is required
Variable phenotype associated with compound LDLR gene mutations in familial hypercholesterolemia patients
Get PDFRationale: Homozygous familial hypercholesterolemia (HoFH) is a rare inherited disorder with an extremely elevated level of low-density lipoprotein (LDL) cholesterol (LDL-C) and accelerated premature coronary artery disease (PCAD). It is primarily caused by a single pathogenic variant of the LDL receptor (LDLR) gene. This report presents 2 rare and unrelated cases of HoFH with compound LDLR mutations. These 2 individuals presented with atypical clinical features and demonstrated variable degrees of hypercholesterolemia.Patient concerns: Case 1 is a 36-year-old Malay woman identified during family cascade screening with a pretreated LDL-C of 8.5 mmol/L and a strong family history of PCAD. Case 2 is a 58-year-old Indian woman discovered to have a pretreated LDL-C of 5.2 mmol/L during routine health screening, without a significant family history of hypercholesterolemia or PCAD. Neither patient demonstrated tendon xanthomas or other lipid stigmata.Diagnoses: Both patients underwent lipid profiling and targeted next-generation sequencing of FH-related genes (LDLR, APOB, PCSK9, ABCG5, and ABCG8). Two novel LDLR variants were identified in exon 18: c.2548-1_2548delGAinsTC (pathogenic) and c.2556_2557insTCAGTCTGG (p.Leu853Serfs*12; likely pathogenic) and classified according to American College of Medical Genetics and Genomics guidelines. Case 1 was homozygous for both variants, while Case 2 was homozygous for the splice-site variant and heterozygous for the frameshift variant.Interventions: Both patients received guideline-directed lipid-lowering therapy and ongoing cardiovascular risk management.Outcomes: Despite biallelic LDLR variants, both patients demonstrated relatively milder hypercholesterolemia and absence of classical HoFH stigmata.Lessons: The LDLR variants located in exon 18 affecting the cytoplasmic tail domain may be associated with attenuated clinical expression. Recognition of genotype–phenotype variability is crucial for accurate diagnosis, risk stratification, and individualized management of HoFH
Daratumumab, bortezomib and dexamethasone for previously treated myeloma – Real-World Outcomes for 2545 patients treated in England
No full textBuilding understanding of digital vulnerability: an exploration of wearable self-tracker usage practices
No full textPurpose – While wearable self-trackers (WSTs) are marketed for self-care, fitness, and health improvement, emerging evidence highlights the potential for negative impacts. This article explores the use of WSTs adopting a practice theory approach to unravel the contextual and individual factors that shape different patterns of WST usage and consumer vulnerability to harm. Design/methodology/approach – A qualitative study using semi-structured interviews and visual stimuli of self-tracking data was conducted with 30 Fitbit users. Data were analysed using thematic analysis, followed by idiographic and cross-case analysis to map usage patterns and reflexivity. Findings – Three distinct WST usage patterns were identified: light, fluctuant and intensive. The study finds that reflexivity on physical activity identity and goals plays a key role in shaping these patterns, with users' critical capacity in identity transitions emerging as a key underpinning factor in vulnerability to harm. Practical implications – To mitigate potential harms and promote healthier self-tracking practices, the study suggests the application of safe design, transparency and accountability principles, accounting for individual goals and experience levels, and tailored guidance and educational support for users. Originality/value – This research focuses on the context of self-tracking and extends existing literature on digital vulnerability, defined as a state in which people are at risk of harm due to external conditions and personal states and circumstances that significantly inhibit their agency in practices involving digital technologies. It reveals differentiated patterns of WST use and the role of identities and identity work in shaping WST use and users’ vulnerability to potential harms
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