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A deep joint source-channel coding scheme for hybrid mobile multi-hop networks
No full textEfficient data transmission across mobile multi-hop networks that connect edge devices to core servers presents significant challenges, particularly due to the variability in link qualities between wireless and wired segments. This variability necessitates a robust transmission scheme that transcends the limitations of existing deep joint source-channel coding (Deep-JSCC) strategies, which often struggle at the intersection of analog and digital methods. Addressing this need, this paper introduces a novel hybrid DeepJSCC framework, h-DJSCC, tailored for effective image transmission from edge devices through a network architecture that includes initial wireless transmission followed by multiple wired hops. Our approach harnesses the strengths of DeepJSCC for the initial, variable-quality wireless link to avoid the cliff effect inherent in purely digital schemes. For the subsequent wired hops, which feature more stable and high-capacity connections, we implement digital compression and forwarding techniques to prevent noise accumulation. This dual-mode strategy is adaptable even in scenarios with limited knowledge of the image distribution, enhancing the framework’s robustness and utility. Extensive numerical simulations demonstrate that our hybrid solution outperforms traditional fully digital approaches by effectively managing transitions between different network segments and optimizing for variable signal-to-noise ratios (SNRs). We also introduce a fully adaptive h-DJSCC architecture with both SNR-adaptive (SA) and rate-adaptive (RA) modules capable of adjusting to different network conditions and achieving diverse rate-distortion objectives, thereby reducing the memory requirements on network nodes
Do carbon prices affect stock prices?
No full textWe explore how carbon pricing affects corporate financial performance during Phase 3 of the European Union Emissions Trading Scheme (EU ETS). We find that the relationship between carbon prices and stock prices depends critically on the proportion of verified emissions covered by freely allocated ETS allowances: For firms with a greater shortfall in emissions allowances (a greater permit coverage), an increase in daily carbon prices is associated with a decrease (increase) in contemporaneous stock prices. We provide additional evidence that firms with a significant permit shortfall reduce verified emissions in the EU, with no apparent carbon-leakage
Bridging the gap: retrospective clinical casefiles analysis defines the key prosthetic provision challenges for children with a major lower-limb absence in Cambodia
No full textIntroduction
Paediatric limb absence results in complex rehabilitation and requires distinct prosthetic care, yet literature on paediatric prosthetic provision remains sparse, hindering improvements in care.
Methods
62 clinical casefiles of children with lower limb absence from prosthetic centres in Cambodia were analysed. Problems related to growth and prosthetic component failures were analysed across limb absence levels. Prosthetic repair and replacement rates were quantified for each component. Residual limb health conditions were reviewed and the impact of socket fit on these conditions was assessed.
Results
Growth posed the largest challenge, particularly for socket fit in knee disarticulation and transtibial cases. Durability issues were common for suspension systems and knees. Donated modular components were less durable than locally manufactured ones (foot: p < 0.001, knee: p = 0.008). Children with transtibial amputations reported more residual limb health issues (bone overgrowth: p = 0.002, wounds: p = 0.018, skin issues: p = 0.010). Poor socket fitting was associated with calluses (p = 0.007) and wounds (p = 0.005).
Discussion
The impact of growth on paediatric prosthetic provision has been quantified for children with different amputation levels. Findings provide insight to manufacturers of prosthetic components on durability considerations. Results provide clarity for care providers on the residual limb conditions to consider for children with different amputation levels and the impact of socket fit on these conditions.
HIGHLIGHTS – NOVEL FINDINGS
Rehabilitation professional should consider the unique challenges growth poses for children with lower limb amputation, particularly socket fit issues in knee disarticulation and transtibial cases
Poor durability of Silesian belt suspension system, prosthetic knee and foot increased clinical burden on children, their families and practitioners in low-resource environments. This should be addressed by prosthetic manufacturers to improve quality of care
Reduced clinical attendance was achieved by providing local components, designed for the intended environments, as these are more durable than those donated from high-resource environments
Children with transtibial amputation reported more residual limb health issues and poor socket fitting was associated with wounds and callu
Validation of acute exacerbation of chronic obstructive pulmonary disease (COPD) recording in electronic health records: a systematic review
No full textObjective: Acute exacerbations of COPD(AECOPD) can have severe impacts on patients with the disease and a heavy burden on health care resources. Electronic health records (EHRs) are a valuable resource for identifying cases of AECOPD and research. Studies have attempted to validate case definitions of AECOPD and this review aims to summarize validated AECOPD definitions in EHRs and to provide guidance on the best algorithms to use to ensure accurate cohorts of AECOPD cases are available for researchers using EHRs.
Methods: MEDLINE and Embase were searched and studies that met the inclusion criteria were reviewed by ≥2 reviewers. Data extracted included the algorithms used to identify AECOPD, the reference standards used to compare against the algorithm, and measures of validity. The risk of bias was assessed using QUADAS-2 adapted for this review.
Results: Out of 2784 studies found by the search strategy, 12 met the inclusion criteria. The clinical terminology used to build algorithms to detect AECOPD included codes from the International Classification of Diseases (ICD) Ninth Revision, Clinical Modification and Tenth Revision (ICD-9-CM and ICD-10), along with the Read codes from United Kingdom general practices. AECOPD can be identified within EHRs using validated definitions, however, the validity of AECOPD definitions varies considerably depending on the algorithm used and the settings to which they are applied.
Conclusion: Although there are validated definitions that can be used to identify AECOPD, there is no clear consensus on which provides the highest validity or the most sensitive and specific definition to use
Impact of socioeconomic deprivation on mechanical thrombectomy outcomes after acute ischemic stroke: findings from a London-based multicentre study
No full textBackground Mechanical thrombectomy (MT) improves outcomes in patients who had an acute ischaemic stroke due to large vessel occlusion (LVO). However, socioeconomic status (SES) can influence recovery and prognosis. This study investigated the effect of SES, assessed via the Index of Multiple Deprivation (IMD), on MT outcomes in a multicentre London cohort.
Methods This retrospective study included patients with anterior circulation LVO treated with MT between 2021 and 2023 at three London hospitals. Patients were grouped into IMD1–5 (more deprived) and IMD6–10 (less deprived). Inverse probability weighting balanced baseline characteristics. Primary outcomes were 90-day functional independence (modified Rankin Scale (mRS) 0–2) and 90-day mRS shift. Secondary outcomes included recanalisation, early neurological changes, 90-day mortality, symptomatic intracerebral haemorrhage (sICH) and haemorrhagic transformation (HT). Subgroup analyses explored interactions between IMD and demographic or clinical factors. LASSO (Least Absolute Shrinkage and Selection Operator) regression identified predictors of functional independence, while receiver operating characteristic analysis evaluated IMD’s predictive value.
Results Among 1219 patients with acute LVO ischemic stroke treated with MT, 533 (43.7%) were in IMD1–5 and 686 (56.3%) in IMD6–10. IMD1–5 patients had lower odds of functional independence at 90 days (RR 0.79, 95% CI 0.70 to 0.90) and worse mRS shift (OR 1.29, 95% CI 1.06 to 1.58). They also had higher risks of sICH (RR 2.07, 95% CI 1.54 to 2.67) and HT (Risk Ratio 1.47, 95% CI 1.21 to 1.80). Subgroup analysis highlighted IMD’s predictive importance in Asian or mixed ethnicity groups. A model incorporating IMD, age, sex, hypertension and National Institutes of Health Stroke Scale (area under the curve 0.656) demonstrated predictive accuracy for 90-day functional independence.
Conclusions Lower SES correlates with worse outcomes and higher complications post-MT, even within a universal healthcare system. Addressing SES disparities could improve stroke care equity
How do electricity TSOs embrace innovation to navigate the energy transition?
No full textAccess to electricity is the lifeblood of modern society. Electricity grids are undergoing transformative changes, driven mainly by decarbonization, decentralization and the integration of variable renewables. Transmission System Operators (TSOs) face increasing pressures from these changes, yet the scale and pace of innovation required to overcome them remain largely unexplored. This study uses interviews with innovation leaders at 11 European TSOs to investigate their approaches to managing the energy transition, focusing on innovation strategies, technology adoption, and future visions. We find that many TSOs adopt decentralized innovation strategies, involving business lines in defining innovation needs and exploring digital and grid technologies to improve efficiency and flexibility. TSOs are using cross-sector collaborations with various decision-making and benchmarking tools to improve performance and better manage emerging technologies like non-wires alternatives. While TSOs seek to adopt new technologies, regulatory constraints, excessive bureaucracy, technology immaturity, skills gaps, and organizational cultural inertia are raised as key barriers. We argue that proactive engagement in innovation, supported by collaboration and regulatory changes could improve TSO resilience and agility. We highlight the importance of integrating innovation into the core strategy of TSOs and the critical need to modernize regulatory frameworks, originally designed for a very different historical context, to eliminate outdated constraints and enable TSOs to more effectively future-proof their organizations
Asset pricing and risk sharing implications of alternative pension plan systems
No full textWe show that incorporating defined benefit pension funds in an incomplete markets asset pricing model improves its ability to match the historical equity premium and riskless rate and has important risk sharing implications. We document the importance of the pension fund’s size and asset demands, and a new risk channel arising from fluctuations in the fund’s returns. We use our calibrated model to study the implications of a shift to an economy with defined contribution plans. The new steady-state is characterized by a higher riskless rate and a lower equity premium. Consumption volatility increases for retirees but decreases for workers
A fully coupled fluid-structure interaction model for patient-specific analysis of bioprosthetic aortic valve haemodynamics
No full textBackground: Bioprosthetic aortic valves (BPAV) have been increasingly used for surgical aortic valve replacement (SAVR), but long-term complications associated with structural valve deterioration remain a concern. The structural behaviour of the valve and its surrounding haemodynamics play a key role in the long-term outcome of SAVR, and these can be quantitively analysed by means of fluid-structure interaction (FSI) simulation. The aim of this study was to develop a fully coupled FSI model for patient-specific analysis of BPAV haemodynamics.
Methods: Using the Edwards Magna Ease valve as an example, the workflow included reconstruction of the aortic root from CT images and the creation of valve geometric model based on available measurements made on the device. Two-way fully coupled FSI simulations were performed under patient-specific flow conditions derived from 4D flow magnetic resonance imaging (MRI), the latter also provided data for model validation.
Results: The simulation results were in good agreement with haemodynamic features extracted from 4D flow MRI and relevant data in the literature. Furthermore, the FSI model provided additional information that cannot be measured in vivo, including wall shear stress and its derivatives on the valve leaflets and in the aortic root.
Conclusion: The FSI workflow presented in this study offers a promising tool for patient-specific assessment of aortic valve haemodynamics, and the results may help elucidate the role of haemodynamics in structural valve deterioration
Mortality among children aged 28 days to 17 years with pneumonia who are not severely undernourished and the effect of macronutrient supplementation: a systematic review and meta-analysis
No full textObjective: Pneumonia is associated with four times higher odds of death among children with severe undernutrition. However, there is an equipoise for the mortality of children without severe undernutrition and the impact of macronutrient interventions. We collated evidence on mortality, anthropometric outcomes and the effect of macronutrient interventions in the management of non-severely undernourished children (28 days–17 years) with pneumonia globally.
Design: Systematic review and meta-analysis using a priori criteria developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline.
Data sources: PubMed, Medline, EMBASE, Web of Science, Google Scholar, Scopus, Cochrane Central and bibliographies were searched between January 2000 and July 2024.
Eligibility criteria: We included articles conducted among children between 28 days and 17 years with pneumonia and non-severe malnutrition that reported on mortality and changes in anthropometric status or macronutrient supplementation. Studies conducted exclusively among adults, on micronutrient supplementation, case studies, commentaries and reviews were excluded.
Data extraction and synthesis: Two reviewers independently screened, abstracted the data and conducted risk of bias (RoB) using standard criteria including the RoB in non-randomised follow-up studies of exposure for observational studies and the revised Cochrane RoB assessment tool for randomised studies (RoB 2.0). Heterogeneity was assessed using the I2 statistic, and subgroup analysis was done. Data were analysed using both narrative and quantitative synthesis. Quantitative synthesis was done using the maximum likelihood random-effects model in STATA V.18.0, with the ‘meta_es’ command.
Results: A total of 15 articles were included (11 conducted in sub-Saharan Africa and four in Asia), with 169 901 participants overall. The mortality among non-severely undernourished children with pneumonia was 3.0% (95% CI 2% to 5%, I2=99.38%), with a range of 1–13% across studies. Children with moderate undernutrition had a higher overall mortality, 9.0% (95% CI 6% to 13%, I2=89.50%), than well-nourished children, with a range of 3–19% across studies. Only one of the 15 studies reported anthropometric outcomes during follow-up and compared mortality rates of those who did versus did not receive macronutrients. The study results were inconclusive.
Conclusions: Mortality among non-severely undernourished children with pneumonia ranges between 1–13% globally. There is inadequate follow-up nutritional assessment and management for non-severely undernourished children with pneumonia
Uses of augmented reality in surgical consent and patient education – a systematic review
No full textAugmented reality (AR) allows the real environment to be altered with superimposed graphics using a head-mounted-display (HMD), smartphone or tablet. AR in surgery is being explored as a potential disruptive technology and could be used to improve patient understanding of treatment and as an adjunct for surgery. The aim was to explore this use of AR and assess potential benefits for consent and patient education. A systematic review was conducted using PRISMA-SCR guidelines. 4 major bibliographic databases were searched using the terms: ‘(augmented reality OR mixed reality) AND surgery AND (consent OR patient education)’. Included papers evaluated an AR intervention on consenting patients for enhancing surgical consent or education about a procedure. Non-English language papers and studies which did evaluate an intervention were excluded. Three reviewers screened all abstracts and full text papers for inclusion. The review protocol was prospectively registered with PROSPERO (ID: CRD42020207360). 52 records were identified. Following removal of 13 duplicates, 21 were removed after abstract screening leaving 17 articles for full assessment. One article was a letter and 8 did not evaluate interventions, leaving 8 articles published between 2019 and 2023. 3 papers were randomised controlled trials comparing AR enhanced processes to standard consent, 2 cohort studies evaluated patient satisfaction with AR interventions and there was one randomised crossover trial of AR against traditional consent consultation. The Cochrane risk of bias tool was used most studies were deemed as high risk of bias. Patient satisfaction and understanding were improved using AR. However, advantages over other enhanced techniques are less clear. Using AR to enhance written literature was shown to require less mental effort from patients and was preferred to standard resources to understand complex surgery. The few randomised trials are limited by bias and lack of power calculation, highlighting the need for further research