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Voices From the Repair Bench: Exploring the Challenges and Needs of Professional Small Electronics Repairers
Full text linkYesSmall electronics make up the largest category of global e-waste, and repair is an important circular economy strategy to extend their lifespan. Professional repairers are central to the repair process, and understanding their experiences is essential for developing effective repair strategies. This study analysed iFixit repair guides collected using machine learning and gathered insights from UK-based professional repairers through surveys and interviews. Findings show that repairers face key design challenges such as strong adhesives, battery and screen access, and complex internal architectures, highlighting the need for modular designs and easy access to priority parts. They also show a strong preference for visual repair guides, ongoing training, and access to professional tools and high-quality, standardized parts to ensure effective repairs
Prevalence of refractive errors in Vietnamese school children: a meta-analysis
No full textYesClinical Relevance: The findings provide greater information on the level of refractive errors in Vietnam, which could assist clinicians and relevant stakeholders to identify high-risk groups and prioritise interventions and preventative measures, contributing to more efficient eye care and cost-effective strategies.
Background/Aims: Vietnam, a developing country in Southeast Asia, has shown an increase in myopia progression in recent years. However, the prevalence of refractive errors across the country is unclear. The aim of this study was to estimate the pooled prevalence of different refractions in children across Vietnam, and to explore differences between rural and urban areas, and male and female children.
Methods: A systematic literature search was performed to capture all studies up to April 2024, using online databases including Medline, Web of Science, Scopus, and CINAHL. This was carried out independently by two researchers, following the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines (PROSPERO ID: CRD42024524780). The quality assessment of included studies was conducted using the Joanna Briggs Institute Prevalence Critical Appraisal Tool checklist. Meta-analysis was performed to estimate pooled refractive error prevalence, with robustness evaluated using 95% confidence intervals and sensitivity analyses.
Results: 15 school-based studies were identified (children n = 32,211), of which 6 qualified for meta-analysis inclusion (n = 15,825). The pooled refractive error, myopia, and hyperopia prevalences were calculated respectively as 37.60% [95%CI: 27.78–47.43], 28.83% [95%CI: 19.24–38.42], and 0.41% [95%CI: 0.24–0.59] with high heterogeneities of 99%, p<0.01. Refractive error prevalence was greater in urban locations, and female children.
Conclusions: This systematic review and meta-analysis of refractive error prevalence in Vietnamese school children indicates a significant presence of refractive error, especially myopia. However, the large interval ranges suggest that further research using a standardised protocol is required to achieve more accurate estimates.Vietnamese Government Scholarship, Ministry of education and training, Vietnam [Grant number: 75/ICD-FG
Frequency and causes of visual impairment in people attending outreach clinics in Zambia
No full textYesClinical relevance: Preventable visual impairment and blindness represent significant global public health challenges. Expanding access to high-volume eye care services in underserved areas may reduce visual impairment and blindness.
Background: Visual impairment negatively impacts quality of life, education, and employability, but is often treatable with management following a basic eye examination. Access to basic eyecare in Zambia is limited. Vision Action, a UK-based nongovernmental organisation, facilitates eyecare services in Zambia to reduce rectifiable visual impairment by supporting government outreach clinics in underserved communities. This study examines the frequency of presenting visual impairment, uncorrected refractive error, and ocular pathology among outreach clinic attendees in Zambia.
Methods: A retrospective analysis of outreach clinic records between 2012 and 2015 was performed. The available data include patient demographics, presenting symptoms, presenting level of vision, and classification of any ocular pathology present. Levels of visual impairment were categorised according to the World Health Organization's classification for blindness and visual impairment.
Results: Data from 5809 patients were collected (58.5% female, mean age = 41.9 years, SD = 20.7 years). Presenting vision, in the better eye, was classified as ‘moderate visual impairment’ in 14.2% (n = 766), ‘severe visual impairment’ in 0.3% (n = 15) and ‘blind’ in 4.3% (n = 234) of individuals. Uncorrected refractive error was responsible for 62.4% and 57.0% of blindness and severe visual impairment, respectively. Cataract, corneal scarring, and glaucoma were the most common non-refractive ocular pathologies associated with visual impairment.
Conclusion: Uncorrected refractive error is the leading cause of blindness and visual impairment in patients presenting to outreach clinics in Zambia and is particularly significant in a predominantly working-age population. Outreach clinics are an effective method of detecting and treating correctable visual impairment in this population. However, there is a need to expand and enhance primary eyecare services to reduce the burden of visual impairment, through management of uncorrected refractive error.CS is supported by a studentship from the Faculty of Life Sciences at the University of Bradford and the original data collection was funded by a College of Optometrists undergraduate research scholarship
Putin has broken one of the most sacred rules of warfare - and the consequences could be dire
No full textNoAttacks on Ukraine’s nuclear energy sites are an unprecedented violation of international law
Gender Justice and Decentralised Energy Resources: Perspectives from the United Kingdom and Nigeria
No full textNoThis chapter analyses the legal dimensions of the challenges and prospects of decentralised energy generation, through a feminist lens. First, decentralization has implications for the ownership structures of the energy systems, establishing new hierarchies in operation, ownership, and distribution structures. The establishment of these hierarchies necessitates the development of a fair, effective, and functional decentralised governance system, presenting the legal challenge of establishing a governance system that upholds gender and energy justice while maintaining efficiency in energy production and consumption. Second, one of the objectives of energy decentralisation is to promote universal access to energy by making it available to places and households that were previously excluded from the grid under the centralised system. This presents the legal issue of the establishment of a balance between the democratisation of energy access and the commercial viability of energy decentralisation by addressing the factors that previously prevented universal connection to the centralized grid within existing legal frameworks. Finally, the production, storage, and consumption of decentralized energy requires adaptation to emerging technologies to maintain environmental sustainability. This capital-intensive practice presents the legal issue of the establishment of a balance between environmental sustainability and universal connectivity to decentralized energy. These three legal issues require direct focus in energy laws and governance systems, to ensure that women and other marginalized groups can access decentralized energy resources (DERs) to address energy poverty and other environmental and equity concerns that are exacerbated by the prevailing centralized energy systems. Against this backdrop, the chapter examines the effectiveness of the energy laws and policies in Nigeria and the United Kingdom in integrating a gender justice lens in DERs design and implementation. Recommendations are made for legal reforms to address the critical challenges of gender equity in the deployment of sustainable DERs in Nigeria and the United Kingdom
Cyclic behavior of steel-FRP composite bars reinforced ultra-high performance concrete frames: Experimental, numerical, and restoring force model analysis
No full textYesThis study investigates the seismic performance of ultra-high performance concrete (UHPC) frame reinforced with steel-FRP composite bars (SFCBs) through cyclic loading tests, finite element modeling, and theoretical analysis. The effect of concrete strength and reinforcement type on the cyclic behavior of frames is examined, focusing on bearing capacity, ductility, performance degradation, energy dissipation, damage and repairability. A refined finite element model is developed using OpenSEES software, and parametric studies is conducted. Based on experimental and numerical results, a restoring force model for SFCB-UHPC frames is proposed. The results demonstrate that replacing normal strength concrete (NSC) with UHPC improves the initial stiffness, bearing capacity, and ductility, enhancing energy dissipation of frames. The steel bar-UHPC frame has a peak load 3.5% and 11% lower than the SFCB-UHPC and basalt FRP (BFRP)-UHPC frames, respectively, with peak displacements reduced by 24% and 42%. Compared with the steel bar-UHPC frame, the SFCB-UHPC frame shows slower performance degradation and better post-earthquake recovery. This study provides a theoretical basis for the analysis and design of SFCB-UHPC frames, offering promising advancements in structural resilience under extreme conditions
Hierarchical attention-enhanced multihead CNN and level sets segmentation: A proposed approach to enhance the cyclone intensity estimation
No full textYesTropical cyclones are considered to be one the most devastating natural disasters, that pose severe threats if not accounted for before its arrival. Predicting the intensity of such tropical cyclones becomes critically important for effective disaster management and response. However, existing techniques of Dvorak’s estimation do not take into account the physical attributes of a cyclone contributing to its intensity and assume a steady state for the same failing to incorporate the temporal aspect to them. This study proposes the use of a Nadam-optimizer based Hierarchical Attention-Enhanced Multihead for real time estimation and Bidirectional Long Short-Term Memory Networks for time series forecasting, with additional pre-processing of difference of Gaussians and level sets segmentation applied. Unlike the aforementioned existing methods, this approach accounts for all physical factors of influence in a cyclone that level sets segmentation leverages to extract contours and cyclonic patterns. Subsequently, the Hierarchical Attention-Enhanced Multihead CNN focuses on these highlighted features to extract intensity aided by the Nadam optimizer, which adapts to any further noise during the gradient estimates in the real time estimation. Likewise, for time series based forecasting, the bidirectional LSTM uses the temporal cyclonic features to predict for next successive time units. Additionally, for further focus on the Region of Interest, being the Indian Ocean as per the used dataset of (IR) satellite images from INSAT-3D Imagery and cyclone maximum sustained wind speed (MSW) details from IBTrACS, coordinate based cropping was applied for the cyclonic extraction. Therefore, the proposed approach establishes itself as a robust tropical cyclone intensity estimation technique, whilst providing superior performance in comparison with other potential deep learning methods like those of AlexNet, CycloneNet, ResNet, LeNet for real time and BiGRU, GRU, Stacked LSTM and such for time series
Do camouflage signals impact performance in reward-based crowdfunding?
No full textPurpose: Reward-based crowdfunding is vital for entrepreneurs who cannot raise funds, but the failure rate to meet funding goals in reward-based crowdfunding is high. Consequently, entrepreneurs try to get backers’ attention and persuade them to pledge funds for their campaigns. Entrepreneurs can provide misleading information in their crowdfunding campaign descriptions, distorting the signals sent to backers. This paper examines how camouflage signals mitigate information asymmetry and its impact on the fundraising ability in reward-based crowdfunding.
Design/methodology/approach: The study examines Kickstarter crowdfunding campaigns (n = 100,522) using six established dictionaries for linguistic hedging as proxies for camouflage signals.
Findings: The results reveal a significant and varied impact of camouflage signals on mitigating information asymmetry and, consequently, on the performance of crowdfunding campaigns; these findings are robust to alternative, independent variables and different econometric techniques.
Originality/value: This study contributes to signalling theory literature through its novel study of camouflage signals. It also contributes to the reward-based crowdfunding literature and provides new insights into how camouflage signals mitigate information asymmetry, thereby persuading or deterring backers from pledging funds
An Overview of Distributed Firewalls and Controllers Intended for Mobile Cloud Computing
No full textYesMobile cloud computing (MCC) is a representation of the interaction between cloud computing and mobile devices, reshaping the utilisation of technology for consumers and businesses. This level of mobility and decentralisation of devices in MCC necessitates a highly secured framework to facilitate it. This literature review on distributed firewalls and controllers for mobile cloud computing reveals the critical need for a security framework tailored to the dynamic and decentralised nature of MCC. This study further emphasises the importance of integrating distributed firewalls with central controllers to address the unique security challenges in MCC, such as nomadic device behaviour and resource allocation optimisation. Additionally, it highlights the significance of Cloud Access Security Brokers (CASBs) in improving data security and ensuring compliance within mobile cloud applications. This review also addresses specific research questions related to security concerns, scalable framework development, and the effectiveness of distributed firewall and controller systems in MCC. It explores the complexities involved in merging Software-Defined Networking (SDN), Network Function Virtualisation (NFV), and CASB into a cohesive system, focusing on the need to resolve interoperability issues and maintain low latency and high throughput while balancing performance across distributed firewalls and controllers. The review also points to the necessity of privacy-preserving methods within CASB to uphold privacy standards in MCC. Furthermore, it identifies the integration of NFV and SDN as crucial for enhancing security and performance in MCC environments, and stresses the importance of future research directions, such as the incorporation of machine learning and edge computing, to further improve the security and efficiency of MCC systems. To the best of our knowledge, this review is the first to comprehensively examine the integration of these advanced technologies within the context of MCC