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Insights into the dynamic electron–hole separation process induced by a trapped electron in lead halide perovskites in the presence of solutions
No full textMetal halide perovskite solar cells show great promise, in terms of their high-power conversion efficiency. However, the dynamic electron–hole separation process remains elusive. Using ab initio molecular dynamics, we discover that the presence of photogenerated electron trapped at a Pb2+ ion can induce significant electron–hole separations on the CH3NH3PbI3 perovskite in the presence of HI solution. In this dynamic process, the separated electron is transferred to the Pb+ ion to form a Pb0 atom, while the separated hole is trapped in an I dimer. The reason behind this induced electron–hole separation is clearly revealed. Furthermore, the charge carrier transfer mechanism is elucidated, which not only explains the carrier migration but also the degradation of the perovskite in a humid environment. Comparing the atomic motions in CH3NH3PbI3 and CH3NH3PbCl3 quantitatively demonstrates that CH3NH3PbI3 is more active but less stable than CH3NH3PbCl3. The proposed mechanism for the electron–hole separation mechanism and perovskite degradation in humid conditions provides insights into the design of a highly efficient perovskite with good stability.<br/
How physical information underlies causation and the emergence of systems at all biological levels
No full textTo bring clarity, the term ‘information’ is resolved into three distinct meanings: physical pattern, statistical relations and knowledge about things. In parallel, three kinds of ’causation’ are resolved: the action of physical force constrained by physical pattern (efficient cause), cybernetic (formal cause) and statistical inference. Cybernetic causation is an expression of fundamental (necessary) logical relations, statistical inference is phenomenological, but physical information and causation are proposed as what actually happens in the physical world. Examples of the latter are given to illustrate the underlying material dynamics in a range of biological systems from the appearance of ‘synergistic information’ among multiple variables (mainly in neuroscience); positional information in multicellular development; and the organisational structure of ecological communities, especially incorporating niche construction theory. A rigorous treatment of multi-level causation is provided as well as an explanation of the causal power of non-physical information structure, especially of interaction networks. The focus on physical information as particular pattern, echoing the insights of Howard Pattee, provides a more physically grounded view of emergence, downward causation and the concept of ‘closure to efficient causation’, all now prevalent in the organisational approach to biology.<br/
Assessment of the feed additive consisting of l-valine produced by fermentation with Corynebacterium glutamicum KCCM 80058 for all animal species for the renewal of its authorisation (CJ Europe GmbH)
No full textFollowing a request from the European Commission, EFSA was asked to deliver a scientific opinion on the assessment of the application for the renewal of the authorisation of l-valine produced by fermentation with a genetically modified strain of Corynebacterium glutamicum KCCM 80058 as a nutritional feed additive for all animal species. The additive is authorised for use in all animal species (3c370). The applicant has provided evidence that the additive currently in the market complies with the existing conditions of authorisation. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the use of the feed additive in animal nutrition remains safe for the target species, consumers and the environment. As regards the safety for the user, l-valine produced by C. glutamicum KCCM 80058 is not an irritant to skin or eyes nor a skin sensitiser. The present application for renewal of the authorisation does not include any modification proposal that would have an impact on the efficacy of the additive and therefore there is no need for re-assessing the efficacy.</p
Rethinking social life cycle assessment for agricultural systems: insights using the pig value chain in the Republic of Ireland as a case study
No full textPurposeSocial Life Cycle Assessment (S-LCA) is a tool used to evaluate the social sustainability of products and systems. The performance reference scale is the commonly used S-LCA approach for agricultural systems but has limitations including reliance on social performance assessments, lack of sector-specific value-added activity variables, and dependence on linear reference scoring. These limitations can lead to inaccurate assessments of social issues. We aimed to develop a methodology for the pork value chain and agricultural systems to overcome these shortcomings.MethodsPerformance reference points were sourced from national and regional pig industry benchmarks, while generic data was used for inventory indicators. Social performance was expressed using ordinal scores which were converted to cardinal scores based on expert judgments. Social performance was converted to social risks using reversed min–max normalization. The “people” activity variable was enhanced by incorporating population and pig densities with pig per capita used to distinguish the local community from society. Social risks were aggregated with social issue weights and activity variables to calculate social risk time, which culminated in the estimation of social hotspot indices. These enhancements were compared using linear and nonlinear scoring methods.Results and discussionAverage social risks were highest for pigs (0.57 vs. 0.64) and lowest for society (0.47 vs. 0.44) for linear and nonlinear methods, respectively. The distribution and ranking of social risk time for social issues varied between the scoring methods across all stakeholder groups. Both linear and nonlinear methods identified pig farm as a social risk hotspot (0.57 vs. 0.65) and the consumption value chain stage as a social opportunity hotspot (0.39 vs. 0.31). The linear scoring method showed a lack of granularity and systematic bias in estimating the social risks, while the nonlinear method was more nuanced due to incorporating contextualization into the reference scores.ConclusionThe proposed methodology highlighted the importance of including social risks and hotspots, alongside social performance, for an agricultural system S-LCA. It demonstrated the advantages of nonlinear scoring over the linear method, overcoming limitations like lack of granularity and systemic bias in the assessment of social issues. However, a limitation of the nonlinear method lies in potential bias when selecting experts for social issue contextualization. This can be mitigated by carefully selecting stakeholder representatives and conducting a sensitivity analysis.<br/
Educational challenges and support for children with congenital heart disease
No full textBackgroundChildren with congenital heart disease (CHD) often face educational challenges due to medical, social, and school-related factors. Early intervention and support for teachers and students are crucial to improving educational outcomes. This study aimed to identify the challenges experienced by teachers, parents, and children with CHD in school settings and explore strategies to enhance their educational experience.MethodA systematic scoping review examined the educational difficulties faced by children with CHD. This was followed by a qualitative study involving three groups: (i) parents of school-aged children with CHD, (ii) teachers with experience teaching these children, and (iii) children and adolescents (ages 11–17) with varying CHD severity. Semi-structured interviews explored participants’ lived experiences and key challenges.ResultsThe scoping review identified challenges in cognitive, psychomotor, behavioural, and emotional domains, as well as issues with school attendance. Teachers often lacked training on CHD-specific needs, impacting their ability to provide adequate support.Qualitative findings revealed concerns from teachers regarding limited CHD-specific knowledge and the risks of having a child with CHD in their class. Parents expressed worries about their children’s academic performance, social interactions, emotional well-being, and physical health. Strong teacher-parent-child communication was seen as essential in reducing anxiety and fostering a supportive school environment.Children’s experiences varied by CHD severity. Children with Hypoplastic Left Heart Syndrome reported most challenges, including fatigue and executive function difficulties. While some children with Transposition of the Great Arteries experienced concentration difficulties, most reported minimal challenges directly related to their condition. Finally, children with Ventricular Septal Defect reported few educational difficulties.ConclusionTeachers require patient-specific information and resources to support children with CHD, especially those with complex conditions. These findings will inform the development of an online training resource to assist teachers and parents in improving educational experiences for children with CHD.<br/
Measuring shame in eating disorders: confirmatory factor analyses and psychometric properties of a new internal and external shame scale
No full textPurposeFeelings of shame can play a role in the development and maintenance of mental disorders. However, the role and measurement of shame in relation to eating disorders remain poorly understood. The current work presents the adaptation of a measure of external and internal shame in relation to eating disorders (EISS-ED) based on an integrative perspective that leverages the strengths of the biopsychosocial model and shame-pride cycle framework. Specifically, the EISS-ED accounts for how individuals believe they are perceived by others (external shame) and how they perceive themselves (internal shame) in relation to eating.MethodsThe study used confirmatory factor analyses to examine the factor structure and psychometric properties of the EISS-ED (N = 478), Spearman’s correlations and Receiver Operator Characteristic curves were used for validity testing.ResultsThe results supported the two-factor structure (including 12 items) of the EISS-ED and its factorial invariance by clinical history and gender. Concurrent validity analyses showed positive correlations between external and internal shame and eating disorder symptoms, negative affect, and detachment. Both external and internal shame measures provided fair classification accuracy of participants based on self-reported history of clinical assessment or treatment for eating disorders.ConclusionsThese findings improve the understanding of the role of shame in eating disorders and offer evidence on a valid assessment that can aid in identifying, measuring, and addressing this important construct, supporting targeted interventions.<br/
Predicting floating photovoltaic platform multi-variable dynamic responses with neural network learning methods
No full textAs global regulators have put an emphasis on turning towards renewable methods of energy production, Floating Photovoltaics has emerged as a growing renewable energy source, first establishing itself with inland installations before expanding into more challenging offshore conditions. Floating Photovoltaics platforms experience significant environmental loading in offshore conditions requiring a rigorous design process and increased monitoring requirements once deployed. On-site monitoring of the Floating Photovoltaic platforms (FPVs) can be difficult for several reasons including installation challenges, environmental conditions, difficulties in access, cost-effectiveness and performance of sensors in such harsh conditions. Alternative methods of monitoring the structure with minimal onboard instrumentation would prove beneficial. Here, Machine Learning (ML), i.e., Neural Networks (NN), when adequately trained, can be effective in predicting the dynamic responses of an FPV platform using minimal sensor input. This paper aims to demonstrate how NN can predict dynamic responses of a Froude-scaled FPV platform in a wave flume by training it on wave profile, mooring line tension and platform motion data. Theis study assesses the performance of a NN with the goal of providing insight on its applications in aiding wave flume tests for photovoltaic platforms. The results of this study indicate that a NN trained on a limited experimental dataset can predict the multi-variable responses of an FPV platform across a range of wave conditions, with certain conditions performing better than others. The neural network performs better in predicting larger wave amplitude conditions, with the heave and pitch predictions performing better than the surge predictions.<br/
Sustainable solutions to repurpose wind turbine blades for offshore applications
No full textThe growing population and advancement in industry have increased energy demand and intensified concern for carbon emissions, generally originating from fossil fuels. To address this issue, many nations have been developing wind turbine farms in both onshore and offshore sectors as wind energy has emerged as a sustainable alternative to fossil fuels, helping to address CO2 emissions. Offshore wind turbines, which have gained traction in the past three decades, are becoming further popular due to their potential for better output and wider available area for installation. However, given wind turbines’ 20–25-year lifespan, accumulating decommissioned blades, generally made of non-biodegradable carbon-reinforced composites or Glass Fibre Reinforced Composite blades at the end of their life service would be a significant challenge that requires thorough evaluation.Many researchers have come up with ideas for repurposing these blades in various applications. However, considering their properties, such as unique geometry, excellent strength compared to the density, and high corrosion resistance, it appears that these blades are capable of reuse in the offshore industry.To assess the importance of this issue, this paper aims to provide an overview of past turbine installations and forthcoming trends, study proposals for repurposing, and finally outline a proposal for repurposing in the offshore industry. Additionally, it discusses necessary assessments to understand the possibility of the proposal in engineering prospect. In the end, the paper estimates the carbon savings achievable through repurposing, highlighting the importance of this approach for sustainability.<br/