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Optical, composition, durability, and environmental properties of the microwave plasma-assisted sputter-deposited silicon nitride
Get PDFA study is presented of the optical, mechanical, composition, durability, environmental, and structural properties of silicon nitride thin films deposited at room temperature using a vertical axis rotating drum-based microwave plasma-assisted sputter system. The deposited material composition was investigated using both X-ray photoelectron spectroscopy (XPS) and elastic recoil detection analysis with time of flight (ERDA-TOF). The results indicate that the layers present a uniform composition with thickness and despite the incorporation of impurities, the Si/N ratio remains close to stoichiometric Si 3 N 4 . The deposited material provides homogeneous low dispersion—with a refractive index of approximately 1.98 over a wide transmittance range (350 nm to 5 µm). Additionally, the single layer silicon nitride was found to be durable with a hardness, Young’s modulus, and compressive stress of 31 GPa, 240 GPa, and −454MPa, respectively. The coating was subjected to and passed external surface environmental tests covered by MIL-C-48497A durability requirements (adhesion, abrasion, and temperature/humidity cycling) and MIL-C-675C (para 4.5.9) salt spray. Moreover, 10,000 wipes on the TS1888 (para 5.4.3) sand slurry abrasion test were achieved with no visible signs of damage. A silicon nitride/silica multilayer durable broadband visible anti-reflection coating is demonstrated, passing the same range of durability and environmental tests as single layer silicon nitride
Modelling sustainability of passenger fleet transition : assessment of policy and environmental outcomes
Get PDFBeing at the forefront of the global electric vehicle (EV) revolution with an amazing 96% of new electric car sales in 2024, it remains questionable if Norway can sustain this momentum over the long term. This study uses a system dynamics model to examine the key drivers of Norway's transition to a zero-emission fleet, focusing on consumer behaviour, policy impacts, and energy-environmental outcomes. A key innovation is the integration of Hofstede's cultural dimensions into the modeling of consumer behavior—an aspect overlooked in previous studies. Findings highlight the importance of vehicle range, affordability, and charging infrastructure. Sensitivity analysis emphasises the role of policy timing, infrastructure, and social influence in market dynamics. Scenario analysis predicts 97% EV sales by 2025 under current policies, with emissions declining by 59% by 2050. The study underscores the need for sustained incentives in the short term, infrastructure expansion, and technological innovation, offering insights for policymakers
Impact of catalyst support impurities on chemical degradation in polymer electrolyte membranes
Get PDFThis study investigates the effect of iron and magnesium impurities present in carbon-based catalyst supports on the chemical degradation of polymer electrolyte membranes (PEMs) in polymer electrolyte fuel cells (PEFCs). A strong linear correlation is found between the iron content on the carbon surface and the degree of membrane thinning after 100-h open circuit voltage (OCV) holding tests, while membrane thinning is depressed by acid treatment. In contrast, magnesium impurities have no significant effect on membrane thinning, but Mg2+ ions cause an increase in ohmic resistance. These findings highlight the critical role of surface Fe impurities in the chemical degradation of PEMs and thereby the durability of PEFCs, as well as the role of Mg in decreasing the ionic conductivity. They also clearly demonstrate that acid treatment of the carbon support is effective in mitigating these modes of degradation, paving the way for the design of more durable PEFCs
The value for money of artificial intelligence-empowered precision medicine : a systematic review and regression analysis
No full textArtificial intelligence has empowered precision medicine (AI-PM) to transform healthcare. This study synthesized available evidence on the cost-effectiveness of AI-PM. We systematically searched five major databases for economic evaluations of AI-PM, extracted data, and assessed risk-of-bias using the Bias in Economic Evaluation (ECOBIAS) checklist. For cost-utility analyses, the value-for-money was quantitatively summarized, and regression analyses incorporating machine learning were conducted to explore value heterogeneity. Forty-eight economic evaluations were included, of which 31 were cost-utility analyses. Although risk-of-bias assessment indicated potential systematic optimism, AI-PM was cost-saving or cost-effective in 89% of base-case analyses, with incremental cost-effectiveness ratios ranging from dominant to 259 to 18 to $986 at a willingness-to-pay threshold equal to one-time per-capita GDP) indicated modest health gains at minimal additional costs, and likely high value heterogeneity. Modeling choices and system-level factors were identified as essential sources of heterogeneity in estimated NMBs. Additional value assessment revealed low adaptability and underreported key value factors, leaving significant uncertainties in AI-PM adoption. [Abstract copyright: © 2025. The Author(s).
Characteristics of individuals from ethnic minority backgrounds who die by suicide : a systematic review
Get PDFWe aimed to estimate the prevalence of clinical and modifiable sociodemographic characteristics of individuals from ethnic minority backgrounds who died by suicide and, where possible, compare them to the majority population. Databases were searched for studies published between 01/01/2000-19/12/2023. Absolute and relative prevalence estimates of characteristics were reported by minority group (Indigenous; migrant; other ethnic minority) then stratified by continent and, where applicable, migrant sub-type and ethnicity. A narrative synthesis was conducted with moderate-high quality studies. We identified fifty-seven studies across 16 countries; the majority from North America, Europe and Oceania. When examining moderate-high quality evidence, there were generally limited numbers of studies reporting the prevalence of each characteristic by ethnic minority status, especially for social factors. Based on the available data, we found a high prevalence mental health problems among people who died by suicide from Indigenous (20.8-60.7 %), migrant (37.2-42.9 %) and other ethnic minority (29.9-37.3 %) backgrounds. However, people from Asian/Pacific Islander, Black and Hispanic backgrounds were less likely to have mental health problems reported compared to majority populations. Indigenous people and migrants generally had lower contact with mental health services compared to majority groups. We also found evidence of a lower prevalence of depression and higher prevalence of alcohol and substance use problems among Indigenous compared to non-Indigenous individuals, and greater levels of economic disadvantage among migrants compared to non-migrants. Our findings highlight differences in the characteristics of people who die by suicide based on ethnicity and migration status and identify potential targets for research and suicide prevention strategies. [Abstract copyright: Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.
Vital engagement and low-meaning flow activities : the interplay between perceived meaningfulness and engagement
No full textAlthough flow experience–a state of simultaneous engagement and enjoyment–is usually considered an “optimal experience,” some studies have identified its undesirable outcomes (e.g., excess gaming, gambling). Whereas flow is typically accompanied by other positive experiences, some research suggests that high engagement during flow may occur independently of perceived meaningfulness. We propose that engaging in a flow activity with different levels of meaningfulness may help account for the inconsistent findings concerning its outcomes. We compare the experience of vital engagement (high perceived engagement and meaningfulness) activities with that of low-meaning flow (high engagement but low meaningfulness) activities. Analyzing data from a 30-day longitudinal study (Study 1; N = 188), a 21-day diary study (Study 2; N = 196), and two experience sampling studies (Studies 3–4; total N = 109), we found that vital engagement activities (vs. low-meaning flow activities) were predominantly associated with more positive experiences, but not necessarily less negative experiences, at the activity level. The relationships between frequency of participation in vital engagement or low-meaning flow activities and personal-level well-being were also less consistent than the activity-level relationships across studies. Taken together, the findings provide partial support to the benefits of participating in vital engagement activities over low-meaning flow activities and highlight the need to consider perceived meaningfulness in everyday activities together with engagement and absorption
Health service contacts for mental health and substance use on release from prison : a retrospective population-based data linkage study
No full textBackground: Mental health and substance use problems among people released from prison contribute substantially to premature mortality and emergency services demand. Understanding of mental health and substance use-related health service contacts prior to these severe and costly outcomes is limited. We assessed mental health and substance use-related contact with multiple services, comparing rates of contact among people released from prison to a matched general population sample who had not recently been in prison. Objectives: To compare rates of health service contacts for mental health and substance use between people released from prison and a matched general population sample. Design: We conducted a retrospective cohort study using linked administrative data with nationwide coverage. The cohort contained all people released from any Scottish prison in 2015 (exposed group), and a random general population sample matched (ratio 1:5) on sex, age, postcode and deprivation indices, who had no imprisonment in the 5 years prior (unexposed group). We linked individual-level administrative healthcare (prescriptions, outpatient, inpatient, emergency/unscheduled care: 2010–2020), prison (admissions, releases: 2010–2020) and deaths records (2015–2020). We estimated adjusted incidence rate ratios (aIRRs) with 95% CIs using fixed-effects Poisson regression with cluster-robust standard errors, controlling for time-in-community, pre-index mental health and substance use-related health service contacts, and comorbidities. We stratified models by mental health (MH), substance use (SU) and dual diagnosis (attributable to both MH and SU). Setting: Scotland. Results: We linked records for 8313 people released from prison, and 41 213 matched individuals. Mental health and substance use-related contact rates were significantly higher for people released from prison across all services, and particularly for emergency and unscheduled care. aIRRs for ambulance contacts were MH=7.75 (95% CI 5.76 to 10.42), SU=7.58 (95% CI 5.71 to 10.08), dual diagnosis=8.28 (95% CI 6.50 to 10.55); and accident and emergency department contacts were MH=4.88 (95% CI 3.78 to 6.29) and SU=7.98 (95% CI 5.71 to 11.17). aIRRs for community prescriptions were MH=1.80 (95% CI 1.67 to 1.94), SU=5.95 (95% CI 4.83 to 7.32), dual diagnosis=5.33 (95% CI 3.70 to 7.68); drug and alcohol services were 7.13 (95% CI 6.00 to 8.48); and outpatient attendances were 2.61 (95% CI 2.17 to 3.16). aIRRs for 24-hour unscheduled telephone support were MH=7.63 (95% CI 4.93 to 11.83) and SU=8.29 (95% CI 3.99 to 17.22); and out-of-hours general practice were MH=5.14 (95% CI 3.66 to 7.22), SU=5.89 (95% CI 3.11 to 11.14) and dual diagnosis=8.85 (95% CI 2.94 to 26.63). aIRRs for general/acute hospital admissions and day cases were MH=2.97 (95% CI 1.43 to 6.16), SU=7.85 (95% CI 4.42 to 13.91), dual diagnosis=13.11 (95% CI 7.95 to 21.61); and for psychiatric admissions were MH=3.62 (95% CI 2.39 to 5.49), SU=10.74 (95% CI 6.12 to 18.84) and dual diagnosis=7.74 (95% CI 4.30 to 13.94). Conclusions: Improved post-release mental health and substance use care is vital for individual and public health. Despite elevated rates of contact with community mental health and substance use services, people released from prison have disproportionately high rates of contact with emergency and unscheduled care services. This suggests that early support is either inadequate or not accessed by those in greatest need. Policymakers and service providers should consider investment in tailored transitional and post-release intervention at individual and population level, to improve health and thus prevent later high-cost service use and avoidable mortality. Our results also suggest high-quality care must be available and accessible beyond the immediate post-release period to permit sustained engagement or engagement at a later date
Evaluating the inherent cyber resilience of inverter-based microgrids against PLL attacks under fault conditions
Get PDFRecently, the concept of inherent cyber resilience has emerged, advocating the use of passive mitigation strategies that leverage the natural dynamics of microgrid components. Prior work has demonstrated that when the phase-locked-loop (PLL) of a grid-following (GFL) inverter is under attack, reducing the droop gain of the closest located grid forming (GFM) inverter effectively mitigates the exhibited voltage sags due to routine load changes. Building on this foundation, this paper first investigates the impact of PLL attacks under major disturbances, such as electrical faults. Simulation studies reveal that fault-induced effects can be magnified, leading to more severe voltage drops, increasing the risk of generator disconnection or even systemwide blackout. Second, it is shown that reducing the droop gain of the GFM inverter effectively restores fault responses to levels observed in an uncompromised system, enhancing system robustness and demonstrating that the concept of inherent cyber resilience remains effective even under fault scenarios
Exploring music preferences, behaviours, and experiences of exercising to music in pulmonary rehabilitation for individuals with chronic respiratory diseases : a cross-sectional survey
Get PDFBackground: Music can enhance exercise performance, but its potential has not been well explored in pulmonary rehabilitation (PR). The aim was to explore the current music-related behaviours among PR service users with chronic respiratory diseases (CRDs) to inform future PR service interventions and explore the potential for music to facilitate exercise adherence in this context. Methods: The cross-sectional survey was distributed among PR attendees at the University Hospitals of Leicester (UHL) NHS Trust in the United Kingdom, between November 2023 and August 2024. Participants completed a 25-item survey exploring (i) relevant technology ownership and music-related behaviours, (ii) preferred music genres and songs and (iii) anticipated benefits/concerns of exercising to music. Quantitative data were analysed descriptively. Free-text data were analysed using qualitative counting. Results: We surveyed 109 people living with CRDs (51% male, 56% aged ≥70 year, 76% chronic obstructive pulmonary disease, 82% owned a smartphone). More than half had no prior experience of exercising to music (n=59, 54%). Despite this, almost half of participants listened to music at least once/day (n=54, 49%), primarily via the radio (n=83, 76%) and/or online music platforms (n=76, 70%). Pop (n=39, 36%) and Country (n=38, 35%) were the most popular music genres listened to, with the majority listening to music without headphones (n=64, 59%). The main concern about wearing headphones while exercising was that it might reduce their awareness of the surroundings (n=67, 61%). The perceived benefits of listening to music during exercise were to boost their mood (n=39, 36%) or help maintain their walking pace (n=19, 17%). Conclusion: There is potential to use music as a tool to support exercise in PR. However, lack of prior experience exercising to music, diverse music preferences, safety considerations and the need to increase knowledge of the potential benefits of exercising to music are key challenges. These findings may help future PR services to implement music into their programmes and develop personalised music-based interventions to optimise exercise performance
Neuromorphic photonic processing and memory with spiking resonant tunnelling diode neurons and neural networks
No full textNeuromorphic computing—modeled after the functionality and efficiency of biological neural systems—offers promising new directions for advancing artificial intelligence and computational models. Photonic techniques for neuromorphic computing hardware are attracting increasing research interest, thanks to their potentials for ultra high bandwidths, low crosstalk, and high parallelism. Among these, approaches based upon resonant tunneling diodes (RTDs) have recently gained attention as potential building blocks for next-generation light-enabled neuromorphic hardware, due to their capacity to replicate key neuronal behaviors such as excitable spiking and refractoriness, added to their potentials for high operational speeds, energy efficiency and compact footprints. In particular, their ability to function as opto-electronic spiking neurons makes them strong candidates for integration into novel event-based neuromorphic computing systems. This work demonstrates the application of optically triggered spiking RTD neurons to a multiplicity of applications and architectures; these include systems based upon single elements for multimodal (photonic-electronic) fast rising edge-detection in time-series data, the construction of a two-layer feedforward artificial photonic spiking neural network (pSNN) using RTD neurons as the nonlinear nodes delivering excellent performance in complex dataset classification tasks, and a pSNN comprised of multiple coupled light-sensitive RTD spiking neurons that supports performance as an adjustable neuromorphic optical spiking memory system with a tunable storage time of spiking patterns
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