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Iron catalysts enhanced by ultrasound for methane decomposition and hydrogen generation
No full textClean hydrogen production offers a viable alternative in the transition to a greener and more sustainable energy future. This study introduces a novel method for enhancing Fe/Al2O3 catalysts using La2O3 and CeO2 doping, aimed at improving hydrogen production via methane decomposition. It addresses the critical challenge of modulating metal-support interaction. Employing ultrasonication in the catalyst preparation, we observed through XRD, H2-TPR, H2 chemisorption, Raman spectroscopy, TGA, and TPO analyses that La2O3 addition prevents FeAl2O4 formation and increases Fe reduction and active sites. Catalysts assisted by ultrasound outperform traditional methods, exhibiting a consistent and significant increase in conversion and yield efficiencies. The La2O3-modified catalysts outperformed the standard Fe/Al2O3 catalyst in methane decomposition. At 800 °C, they demonstrated enhanced activity and stability under demanding conditions, achieving a methane conversion of 93% and hydrogen yield of 84%. This approach boosts hydrogen production and contributes to the development of sustainable and efficient energy solutions.<br/
Microarchitecture design and benchmarking of custom SHA-3 instruction for RISC-V
No full textIntegrating cryptographic accelerators into modern CPU architectures presents unique microarchitectural challenges, particularly when extending instruction sets with complex and multistage operations. Hardware-assisted cryptographic instructions, such as Intel’s AES-NI and ARM’s custom instructions for encryption workloads, have demonstrated substantial performance improvements. However, efficient SHA-3 acceleration remains an open problem due to its distinct permutation-based structure and memory access patterns. Existing solutions primarily rely on standalone coprocessors or software optimizations, often avoiding the complexities of direct microarchitectural integration. This study investigates the architectural challenges of embedding a SHA-3 permutation operation as a custom instruction within a general-purpose processor, focusing on pipelined simultaneous execution, storage utilization, and hardware cost. In this paper, we investigated and prototyped a SHA-3 custom instruction for the RISC-V CPU architecture. Using cycle-accurate GEM5 simulations and FPGA prototyping, our results demonstrate performance improvements of up to 8.02× for RISC-V optimized SHA-3 software workloads and up to 46.31× for Keccak-specific software workloads, with only a 15.09% increase in registers and a 11.51% increase in LUT utilization. These findings provide critical insights into the feasibility and impact of SHA-3 acceleration at the microarchitectural level, highlighting practical design considerations for future cryptographic instruction set extensions.<br/
Safety and efficacy of a feed additive consisting of l-valine produced with Corynebacterium glutamicum KCCM 80365 for all animal species (CJ Europe GmbH)
No full textFollowing a request from the European Commission, the European Food Safety Authority (EFSA) was asked to deliver a scientific opinion on the safety and efficacy of l-valine produced with a genetically modified strain of Corynebacterium glutamicum (KCCM 80365) when used as a nutritional additive in feed and water for drinking for all animal species and categories. l-Valine manufactured by fermentation using C. glutamicum KCCM 80365 does not give rise to any safety concern regarding the genetic modifications of the production strain. No viable cells or DNA of the production strain were detected in the final product. The use of l-valine produced with C. glutamicum KCCM 80365 in feed is safe for the target species when supplemented in appropriate amounts to the diet according to the nutritional needs of the species. The FEEDAP Panel has concerns on the use of l-valine in water for drinking. The use of l-valine produced by fermentation with C. glutamicum KCCM 80365 in animal nutrition is considered safe for the consumers and for the environment. l-Valine produced with C. glutamicum KCCM 80365 is not irritant to skin and eyes, nor considered a skin sensitiser. The additive l-valine is regarded as an effective source of the amino acid l-valine for all non-ruminant species. To be as efficacious in ruminants as in non-ruminants, it should be protected from ruminal degradation.</p
The effects of schools providing compensatory cultural capital on student reading in the case of Taiwanese students participating in the PISA
No full textThe structural approach of cultural capital theories neglects the idea that the impact of structural constraints on educational results can be reduced by agency. This predicament can be solved when the advantages of abundant educational resources available in schools are unpacked since doing so can compensate for the paucity of such resources often seen in the low-SES family social space. Although the gains available from such resources remain embedded in the school social space, it can be assumed that their compensatory function can be activated through reading activities that significantly contribute to students’ cognitive development. This situation prompts two research questions related to the contributions of reading to academic disciplines such as math and science and the amelioration of the structural impact of SES and cultural capital on low-SES students’ learning outcomes. To explore these questions, we used regression analysis and hierarchical linear modelling (HLM) to analyse data from the stratified random sample of Taiwanese students (n=7,342) contained in the PISA 2018 dataset. The estimates of regression analysis showed that reading ability functioned as a reliable indicator of Taiwanese students’ math and science scores on PISA 2018. The results of HLM (hierarchical linear modeling) analysis further demonstrated that the predominant influence of ESCS and cultural capital can be significantly attenuated when the independent variables of school support and student personal efforts/learning strategies are considered. Accordingly, reading resources can be regarded as a compensatory genre of cultural capital embedded within the school social space, at least in the case of Taiwan, as the benefits they create need to be achieved through reading plans/projects scientifically implemented by schools
Challenging the role of good character evidence in rape trials: monsters, myths and mitigation
No full textThis paper explores rape reform in the context of the 2019 Gillen Review in Northern Ireland. While the challenges presented by rape myths featured heavily in the review, the relationship between rape myths and character evidence was not considered. In addressing this gap, this paper argues that the admission of good character evidence on behalf of the accused contributes to a hierarchy of rape, with violent rape by ‘monsters’ at the top and ‘mistakes’ by ‘good guys’ at the bottom. In doing so, the paper furthers important conversations on character evidence in scholarship on evidence and proof, as well as the critical feminist literature on rape. Further to this, in considering reform options the paper makes a practical contribution by arguing that, while reform to the admission of good character evidence during trial should be treated with caution, such evidence should be formally removed as a mitigating factor during sentencing.<br/
Polygenic risk score impact on visual function in older individuals with healthy macula: the Northern Ireland sensory ageing study
No full textBackground/objectivesAlthough polygenic risk scores (PRSs) have been developed for age-related macular degeneration (AMD), it is not known whether these scores are associated with impairment of visual functions in older individuals with healthy macula. We evaluated age-related changes in visual function in people aged 55 years or above with healthy macula and determined the associations of age-related visual function changes with AMD PRS in people with healthy macula.Subjects/MethodsParticipants aged 55 years or above with healthy macula and a comparative group of people with early or intermediate AMD from the Northern Ireland Sensory Ageing study were included. 45 SNPs were included for PRS calculation.ResultsA total of 470 participants with healthy macula were included (Beckman grade 0 or 1). The comparator group consisted of participants with early AMD (n = 87) or intermediate AMD (n = 48). All visual functions except metrics of central visual field assessment showed a significant decline with age in adjusted linear regression models. Rod intercept time (RIT) was the only visual function significantly associated with PRS with Beta = 0.12 (95% confidence interval: 0.01–0.23), P = 0.03. A PRS integrated model achieved the highest area under the receiver operating characteristic curve (AUC) of 0.803 (0.732 to 0.874) to distinguish between normal or increased RIT.Conclusions and relevanceWe observed a significant decline in multiple visual functions with increasing age. However, PRS was significantly associated with RIT only, highlighting the genetic association of age-related decline in rod function.<br/
Controlling fragment size distribution for modelling the breakage of multi-sphere particles
No full textVoro-Pack, an open-source code is introduced to reconstruct real particles into multi-sphere clusters consisting of fragments with controlled size distributions, enabling experiment-informed fragment size distributions (FSD). Two types of silica sand are employed to evaluate the performance of the code, where FSD data are obtained through laser diffraction and sieving, and particle shape information is obtained through micro computed tomography. The results show that the particle sizes and shapes of the multi-sphere clusters generated by the code are in good agreement with those of real particles. It is found that the fragment sizes in the multi-sphere clusters aligned more closely with the real FSD data when laser diffraction data were used as input, compared to sieving. The volume ratio of the multi-sphere clusters to the actual particles is a key factor influencing the size distribution of fragments, with better matching to the actual FSD data when the volume ratio exceeds 0.5 and approaches 1.0. Additionally, the particle shape characteristics do not significantly affect the FSD data in the code-generated clusters. These findings suggest that the Voro-Pack code is an effective tool in reconstructing multi-sphere clusters for particles of various morphologies, providing valuable insights into modelling the breakage of granular materials.<br/
AI for glaucoma, are we reporting well? a systematic literature review of DECIDE-AI checklist adherence
No full textBackground/ObjectivesThis systematic literature review examines the quality of early clinical evaluation of artificial intelligence (AI) decision support systems (DSS) reported in glaucoma care. Artificial Intelligence applications within glaucoma care are increasing within the literature. For such DSS, there needs to be standardised reporting to enable faster clinical adaptation. In May 2022, a checklist to facilitate reporting of early AI studies (DECIDE-AI) was published and adopted by the EQUATOR network.MethodsThe Cochrane Library, Embase, Ovid MEDLINE, PubMed, SCOPUS, and Web of Science Core Collection were searched for studies published between January 2020 and May 2023 that reported clinical evaluation of DSS for the diagnosis of glaucoma or for identifying the progression of glaucoma driven by AI. PRISMA guidelines were followed (PROSPERO registration: CRD42023431343). Study details were extracted and were reviewed against the DECIDE-AI checklist. The AI-Specific Score, Generic-Item Score, and DECIDE-AI Score were generated.ResultsA total of 1,552 records were screened, with 19 studies included within the review. All studies discussed an early clinical evaluation of AI use within glaucoma care, as defined by the a priori study protocol. Overall, the DECIDE-AI adherence score was low, with authors under reporting the AI specific items (30.3%), whilst adhering well to the generic reporting items (84.7%).ConclusionOverall, reporting of important aspects of AI studies was suboptimal. Encouraging editors and authors to incorporate the checklist will enhance standardised reporting, bolstering the evidence base for integrating AI DSS into glaucoma care workflows, thus help improving patient care and outcomes.<br/
