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Insights into the role of Ce and Sm in improving low-temperature NH3-SCR performance over Ce-Sm/Cu-SSZ-13 coupled catalysts
No full textThe increasingly stringent requirements for controlling nitrogen oxide (NOx) emissions during the cold start conditions of diesel engines serve as a powerful driving force to enhance the low-temperature NH3-SCR performance of state-of-the-art commercial Cu-SSZ-13. In this study, the coupled catalysts were synthesized to create additional active sites for NO oxidation and NH3 adsorption/activation, and the synergistic effect between Cu species and CeO2/Sm2O3 leads to a substantial boost in the low-temperature NH3-SCR activity of CSZ. The results suggest that 6 % Ce-2 % Sm/CSZ, as the optimal coupled catalyst, achieves a NOx conversion of 93.1 % at 200 °C, significantly higher than that of CSZ. The coupled CeO2 and Sm2O3 enhance the number of both Brønsted and Lewis acid sites on CSZ, promoting the adsorption and activation of NH3. Therefore, 6 % Ce-2 % Sm/CSZ can form more NH+4 adsorbed on the Lewis acid sites, which reacts with free ionic nitrates to form NH4NO3. More importantly, the coupled Sm2O3 facilitates the conversion of NH4NO3 by NO to easily decomposable NH4NO2. In addition, additional oxygen vacancies provided by Ce3+ can adsorb O2 and promote the transport of oxygen ions, and electron donation from Sm3+ to [ZCu2+(OH)]+ enhances the low-temperature activity of the latter. Ultimately, the low-temperature NH3-SCR performance of CSZ is improved via a synergistic effect. The NH3-SCR reaction over 6 % Ce-2 % Sm/CSZ co-follows the Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms
Treatment of enteric fever (typhoid and paratyphoid fever) with cephalosporins: a Cochrane review
No full textSpin-Polarized Nonferromagnetic Surfaces for Electrocatalysis: Chemo-Spintronics
No full textCatalysts achieve changes in the rate through modification of the free energy of adsorbed intermediates and transition states (TrS). Binding energies of intermediates and TrS are strongly correlated, and modifications in catalyst composition are often ineffective in breaking these correlations, leading to minimal change in rate. Such scaling relationships are reported throughout catalysis. The surface spin state of a magnetic metal can change adsorption energies, offering a way to overcome scaling relationships. However, experimentally, this approach appears reliant on the use of ferromagnetic materials, limiting applicability. Here, we show that tunable changes in electrocatalytic activity for the hydrogen evolution reaction (HER) can be achieved at (originally) nonmagnetic metals (Au and Pt) through the use of a multilayer electrode structure that contains a ferromagnetic alloy (CoB) beneath a thin (5-20 nm) film of Pt or Au. Analysis of the dependence of the catalytic current on the thickness of the Au or Pt capping layer and on the direction of the stray magnetic field allows us to rule out the presence of magnetohydrodynamic effects. Instead, we conclude that transfer of ferromagnetism from the ferromagnet to the Au or Pt takes place through proximity-induced magnetism (PIM) via exchange interactions and/or a spin polarized current. Density Functional Theory simulations trace changes in the breaking of the scaling relationship for the Tafel HER mechanism. Overall, our experiments show that thin-film electrodes, based on routine structures from the spintronics community, are a potentially versatile platform for achieving spin-polarized catalysis at originally nonmagnetic metals
spanishoddata: A package for accessing and working with Spanish Open Mobility Big Data
No full textWe present spanishoddata, an R package that enables fast and efficient access to Spain’s open, high-resolution origin-destination human mobility datasets, derived from anonymised mobile-phone records and released by the Ministry of Transport and Sustainable Mobility. The package directly addresses challenges of data accessibility, reproducibility, and efficient processing identified in prior studies. spanishoddata automates retrieval from the official source, performs file and schema validation, and converts the data to efficient, analysis-ready formats (DuckDB and Parquet) that enable multi-month and multi-year analysis on consumer-grade hardware. The interface handles complexities associated with these datasets, enabling a wide range of people – from data science beginners to experienced practitioners with domain expertise – to start using the data with just a few lines of code. We demonstrate the utility of the package with example applications in urban transport planning, such as assessing cycling potential or understanding mobility patterns by activity type. By simplifying data access and promoting reproducible workflows, spanishoddata lowers the barrier to entry for researchers, policymakers, transport planners or anyone seeking to leverage mobility datasets
From interaction to competency: the mediating role of social engagement in the emergence of materials-use competency among pre-service EFL teachers
No full textDespite increasing attention to teacher professionalism, little is known about the micro-level classroom processes through which pre-service EFL teachers develop materials-use competency, especially in resource-constrained contexts where lecture materials dominate. Grounded in sociomaterialism, this study examines how social engagement during lecture-initiated interactions mediates the emergence of pre-service EFL teachers’ materials-use competency. The dataset comprises 1,770 student responses across 28 classes in a teacher education module in Southwest China, analysed through two-round grounded coding, multimodal conversation analysis, and thematic analysis of instructor and student interviews. Three patterns of interactional entanglement (low, medium, high) were identified. These patterns shaped the conditions for dialogic learning, and it was particularly high-quality social engagement that mediated whether pre-service teachers transformed lecture discourse into situated instructional resources, enabling interactive designs. Structural and interactional constraints, including multimodal asymmetries and superficial translingual interactions, limited the occurrence of high-quality social engagement, thereby constraining the emergence of materials-use competency. The study contributes to sociomaterial perspectives in teacher education by showing how interactional entanglement and social engagement jointly shape the emergence of materials-use competency. Findings highlight the need to foreground social engagement in fostering such competency in teacher preparation
Implementing circular practices through supply-chain configurations of service offerings for consumer products
No full textPatient and public perspectives on the availability of their health and advance care planning information to support care at the end of life: a mixed-methods questionnaire study
No full textObjective To explore patient and public views and experiences of health professional access to patient health records and advance care planning information to support care at the end of life.
Design A cross-sectional national online survey of patients and the public using a convergent-parallel approach.
Setting The survey was distributed across the UK by Compassion in Dying and promoted via newsletters and social media channels of the Professional Records Standards Body and NHS England’s digital workstream network. These partners were purposively selected for their active involvement in end-of-life care, including hospices, clinicians and related charities.
Participants A total of 1728 participants from 103 UK counties responded, including people with a terminal condition (n=33), with long-term condition (n=442), who provide or have provided care to a person with a long-term or terminal illness (n=229) and who identified as healthy and interested in planning for the future (n=1024).
Measures Both quantitative data (multiple-choice responses and numerical ratings) and qualitative data (open-ended comments) asking about experiences and views of access to their health and advance care planning information to support their care at the end of life.
Results Confidence that recorded care preferences would be accessed when needed was low for carers (median=2, IQR 1–4) and moderate for patients (median=3, IQR 1–4). Four themes derived from free-text responses included (1) experience of sharing health information; (2) preparation, communication and understanding; (3) concerns, unknowns and assurance seeking; and (4) preserving dignity and respect: understanding individual contexts.
Conclusions Respondents acknowledged the opportunity for digital systems to enable access to health and advance care planning information but expressed doubts that professionals would retrieve it when needed, citing past failures. Confidence in record accuracy could be strengthened by patient and carer access. Future research should examine whether such access improves alignment of care with patients’ wishes
Species Contributions to Biotic Homogenisation and Differentiation
No full textAim Homogenisation (decreasing beta-diversity) among biological assemblages is often interpreted as being caused by already-widespread species increasing. The link between individual species level trends and homogenisation between assemblages, however, has not been fully addressed, with most studies focused solely on either assemblage level or species level changes. Here we aim to test the widely held hypothesis that homogenisation is driven by the decrease of localised species and increase of those already widespread using species contribution to beta-diversity. Location North America, Europe, South Africa. Time Period 1970 to 2019, 1966 to 1996, 11,700 years ago to present, 2011 to 2021, 1960 to 2016. Major Taxa Studied Birds, plants, benthos and mammals. Methods Here, we consider individual species contributions to spatial beta-diversity and how these change over time. We focus on the relative contributions of localised and widespread species across five case studies to determine which are contributing most to homogenisation. Results Species occurring in around half of sites provided the greatest contributions to beta-diversity at a given time, but not through time. The most widespread species (> 0.75 of sites) contributed little to beta-diversity change, with this most apparent in highly nested assemblages. In contrast, localised species (initially in < 0.25 of sites) contributed most to both homogenisation (when declining) and differentiation (when increasing) regardless of nestedness. Main Conclusions This challenges the hypothesis that widespread generalist species are the main drivers of homogenisation, underlining the importance of rare species and of nestedness to patterns of beta-diversity change. Conservation interventions to increase localised species occurrence would do more to limit homogenisation than attempts to control already-widespread species or prevent others becoming widespread, especially when assemblages are highly nested
Unequal educational outcomes for children with similar early childhood vocabulary but different socio-economic circumstances
No full textBackground
In a purely meritocratic society, educational outcomes would reflect ability and only ability. Vocabulary size is a common measure of cognitive ability that predicts educational outcomes but is confounded with socioeconomic circumstances (SEC).
Methods
In preregistered analyses of the nationally representative UK Millennium Cohort Study data (N = 15,576), we used a series of multiple linear and logistic regression analyses to investigate the predictive value of age-5 vocabulary for age-16 educational outcomes and assess whether socioeconomic circumstance moderated this relation.
Results
We show that age-5 vocabulary strongly predicted age-16 educational attainment, even after adjusting for both SEC and caregiver vocabulary (OR = 1.62, 95% CIs = [1.52; 1.72]; β = .22, 95% CIs = [0.19; 0.24]). SEC also predicts educational attainment (OR = 2.05, 95% CIs = [1.92; 2.19]), and modifies the association between vocabulary and educational attainment, whereby a larger vocabulary was most advantageous for those in middle SEC groups (interaction term OR = 1.09 [1.03; 1.15]).
Conclusions
Early child vocabulary is a strong predictor of children's educational outcomes – even when controlling for proxy measures of the home environment and genetics. Nonetheless, children who enter school with strong vocabulary skills but disadvantaged socioeconomic circumstances still have only about a 50/50 chance of gaining gateway qualifications at age 16
An exploration of patient and family carers’ views of dietary intervention for psychosis care and management
No full textPsychosis greatly impacts affected individuals and their families. Current pharmacological treatments are not fully efficacious and are associated with a range of metabolic side-effects. As a result, patients and their families seek alternative interventions, including managing their diet. Psychosis treatment guidelines recommend dietetic support as part of psychosis treatment, however this has not become embedded within routine practice. The aim of this study was to determine the views of patients and their families on the value of dietary intervention in their psychosis care and management. Study participants (n = 14) were either accessing psychosis treatment services (n = 8) or were familial carers (n = 6). Data were collected via individual semi-structured interviews and were thematically analysed resulting in four themes: 1) ‘What constitutes a healthy diet?’, 2) ‘The connection between diet, the brain and symptoms’, 3) ‘Empowerment gained from finding my own self-management strategies’ and 4) ‘How we envision dietary management for psychosis’. Findings suggest participants would value having access to a diet intervention to aid their management of psychosis, delivered by knowledgeable health care practitioners within mental health services. Participants wanted the dietary intervention to be evidence-based, accessible and have outcomes which including improved dietary knowledge and skills. The principal recommendation following this research is to further develop a dietary intervention for psychosis care and management that is co-designed with health staff, people with psychosis and their familial carers, mental health service commissioners and academics responsible for educating health care practitioners' curricula