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Self-supported iron-based bimetallic phosphide catalytic electrode for efficient hydrogen evolution reaction at high current density
No full textIron (Fe)-based materials, which are abundant in Earth's crust, can be competent candidates as electrocatalysts for large-scale and sustainable alkaline hydrogen evolution reaction (HER); however, unlocking their huge potential critically relies on the rational integration of their structures and electrode materials. Herein, we report the construction of FeP-based bimetallic electrodes through a facile soaking-phosphorization approach. The hierarchical structure of porous iron foam (IF)-nanosheet arrays (NAs) endows enhanced reaction kinetics under high current densities. Modification with different transition metal cations evidently improves the intrinsic catalytic activity of FeP, among which cobalt-modified FeP (CoFe-P) shows the best performance. The optimized CoFe-P NAs/IF electrode exhibits an outstanding catalytic performance in the HER in alkaline media, with a current density of 10 mA cm−2 at an extremely low overpotential of 40 mV. Additionally, at high current densities of 500 and 1000 mA cm−2, the electrode requires impressively low overpotentials of 151 and 162 mV, respectively. Furthermore, the catalytic performance experiences minimal degradation after a stability test at 500 mA cm−2 for 200 hours, suggesting the exceptional stability of the CoFe-P NAs/IF electrode
Advanced patient-specific microglia cell models for pre-clinical studies in Alzheimer's disease
No full textBackground: Alzheimer’s disease (AD) is an incurable neurodegenerative disorder with a rapidly increasing prevalence worldwide. Current approaches targeting hallmark pathological features of AD have had no consistent clinical benefit. Neuroinflammation is a major contributor to neurodegeneration and hence, microglia, the brain’s resident immune cells, are an attractive target for potentially more effective therapeutic strategies. However, there is no current in vitro model system that captures AD patient-specific microglial characteristics using physiologically relevant and experimentally flexible culture conditions. Methods: To address this shortcoming, we developed novel 3D Matrigel-based monocyte-derived microglia-like cell (MDMi) mono-cultures and co-cultures with neuro-glial cells (ReNcell VM). We used single-cell RNA sequencing (scRNAseq) analysis to compare the transcriptomic signatures of MDMi between model systems (2D, 3D and 3D co-culture) and against published human microglia datasets. To demonstrate the potential of MDMi for use in personalized pre-clinical strategies, we generated and characterized MDMi models from sixteen AD patients and matched healthy controls, and profiled cytokine responses upon treatment with anti-inflammatory drugs (dasatinib and spiperone). Results: MDMi in 3D exhibited a more branched morphology and longer survival in culture compared to 2D. scRNAseq uncovered distinct MDMi subpopulations that exhibit higher functional heterogeneity and best resemble human microglia in 3D co-culture. AD MDMi in 3D co-culture showed altered cell-to-cell interactions, growth factor and cytokine secretion profiles and responses to amyloid-β. Drug testing assays revealed patient- and model-specific cytokine responses. Conclusion: Our study presents a novel, physiologically relevant and AD patient-specific 3D microglia cell model that opens avenues towards improving personalized drug development strategies in AD
Sympathetic determinants of resting blood pressure in males and females
No full textDischarge of postganglionic muscle sympathetic nerve activity (MSNA) is related poorly to blood pressure (BP) in adults. Whether neural measurements beyond the prevailing level of MSNA can account for interindividual differences in BP remains unclear. The current study sought to evaluate the relative contributions of sympathetic-BP transduction and sympathetic baroreflex gain on resting BP in young adults. Data were analyzed from 191 (77 females) young adults (18–39 years) who underwent continuous measurement of beat-to-beat BP (finger photoplethysmography), heart rate (electrocardiography), and fibular nerve MSNA (microneurography). Linear regression analyses were computed to determine associations between sympathetic-BP transduction (signal-averaging) or sympathetic baroreflex gain (threshold technique) and resting BP, before and after controlling for age, body mass index, and MSNA burst frequency. K-mean clustering was used to explore sympathetic phenotypes of BP control and consequential influence on resting BP. Sympathetic-BP transduction was unrelated to BP in males or females (both R2 < 0.01; P > 0.67). Sympathetic baroreflex gain was positively associated with BP in males (R2 ¼ 0.09, P < 0.01), but not in females (R2 < 0.01; P ¼ 0.80), before and after controlling for age, body mass index, and MSNA burst frequency. K-means clustering identified a subset of participants with average resting MSNA, yet lower sympathetic-BP transduction and lower sympathetic baroreflex gain. This distinct subgroup presented with elevated BP in males (P < 0.02), but not in females (P ¼ 0.10). Sympathetic-BP transduction is unrelated to resting BP, while the association between sympathetic baroreflex gain and resting BP in males reveals important sex differences in the sympathetic determination of resting BP. NEW & NOTEWORTHY In a sample of 191 normotensive young adults, we confirm that resting muscle sympathetic nerve activity is a poor predictor of resting blood pressure and now demonstrate that sympathetic baroreflex gain is associated with resting blood pressure in males but not females. In contrast, signal-averaged measures of sympathetic-blood pressure transduction are unrelated to resting blood pressure. These findings highlight sex differences in the neural regulation of blood pressure
Patients and health care workers perceived challenges in managing preeclampsia, in Malawi
No full textObjectives: This study investigated perceptions of the challenges for patients and health care workers (HCW) in dealing with preeclampsia in Blantyre, Malawi. Methods: A descriptive cross-sectional formative study using semi-structured In-Depth Interviews (IDI) was conducted at Queen Elizabeth Central Hospital (QECH), Malawi. Data was analyzed using NVIVO™ software. Thematic content analysis was used to analyze and interpret the findings. Emerging themes were then developed inductively and deductively. Patients were interviewed who recently had preeclampsia. Results: Stress, lack of information, physical symptoms, delay in receiving care were identified challenges to better care among patients as well as the impact of poor pregnancy outcomes. Late diagnosis, staff burn out, inadequate skills and lack of resources were expressed as challenge to provide better management by the interviewed HCWs. Conclusion: Our study showed that a diagnosis of preeclampsia is challenging to both patients and HCWs. These challenges need to be addressed carefully at all levels for optimal management of preeclampsia in Malawi, Africa and in order to improve outcomes
Leaf phosphorus fractions vary with leaf economic traits among 35 Australian woody species
No full textAdaptations of plants to phosphorus (P) deficiency include reduced investment of leaf P in storage (orthophosphates in vacuoles), nucleic acids and membrane lipids. Yet, it is unclear how these adaptations are associated with plant ecological strategies. Five leaf P fractions (orthophosphate P, Pi; metabolite P, PM; nucleic acid P, PN; lipid P, PL; and residual P, PR) were analysed alongside leaf economic traits among 35 Australian woody species from three habitats: one a high-P basalt-derived soil and two low-P sandstone-derived soils, one undisturbed and one disturbed by human activities with artificial P inputs. Species at the undisturbed low-P site generally exhibited lower concentrations of total leaf P ([Ptotal]), primarily associated with lower concentrations of Pi, and PN. The relative allocation of P to each fraction varied little among sites, except that higher PL per [Ptotal] (rPL) was recorded at the undisturbed low-P site than at the high-P site. This higher rPL, reflecting relative allocation to membranes, was primarily associated with lower concentrations of leaf nitrogen at the undisturbed low-P site than at the high-P site. Associations between leaf P fractions and leaf nitrogen may provide a basis for understanding the variation in plant ecological strategies dependent on soil P availability
[In Press] Adolescents' intentions to study science : the role of classroom-based social support, task values, and self-efficacy
No full textDeclining enrolments in senior secondary science have heightened concerns for meeting the demands for more STEM-qualified workers and a scientifically literate society. Students' attitudes to science are formed during schooling, particularly in adolescence when they are exposed to a variety of science topics. Students’ perceptions of their ability in science and their subjective task values are well established as predictors of their likelihood of engaging with and continuing their study of science. However, the role of classroom-based social support in supporting ability perceptions and task values is less well understood. In this study, we examined relationships between adolescents’ perceived classroom-based social support, task values, and self-efficacy, and how these perceptions and attitudes predicted adolescents’ intentions to study the three major science subjects (biology, chemistry, and physics) in senior high school. Participants were 475 adolescents in Grades 8 to 10 recruited from six schools in Sydney, Australia. Structural equation modelling was employed to test the hypothesised model in which social support from science teachers and peers predicted intended science subject selections through science self-efficacy, intrinsic valuing of science, and utility value of science. Results indicate that science teacher and peer support were not directly related to adolescents’ intentions to study senior science subjects. Instead, they were indirectly related via their positive relationship with science self-efficacy and task values. Utility value was the strongest predictor of adolescents’ intentions to study biology, chemistry, and physics, while self-efficacy and intrinsic value also predicted adolescents’ intentions to study chemistry. These results suggest that classroom-based social supports are important for supporting adolescents’ attitudes towards science, and that science utility value interventions may be useful in efforts to improve enrolments in senior science subjects
[In Press] New consensus definition on defining and measuring care for children with paediatric feeding disorder
No full textAim: This study addresses the absence of a definition of care for children with feeding disorders, limited agreement on key performance indicators (KPIs), and the lack of data linked to those KPIs. Methods: Clinicians, consumers and researchers involved in outpatient feeding care in New South Wales (NSW), Australia were invited to participate in a two-Phase study. In Phase 1, a modified Delphi method was used. Two rounds of voting resulted in a new consensus definition of a multidisciplinary paediatric feeding clinic. Three further rounds voting determined relevant KPIs. In Phase 2, the KPIs were piloted prospectively in 10 clinics. Results: Twenty-six clinicians, consumers and researchers participated in Phase 1. Participation across five voting rounds declined from 92% to 60% and a valid definition and KPI set were created. In Phase 2, the definition and KPIs were piloted in 10 clinics over 6 weeks. Data for 110 patients were collected. The final KPI set of 28 measures proposed covers clinical features, patient demographics and medical issues, parent–child interaction and outcome measures. Conclusions: A new definition of a multidisciplinary paediatric feeding clinic is now available, linked to a standardised KPI set covering relevant performance measures. These proved viable in baseline data collection for 10 clinics across NSW. This sets a foundation for further data collection, systematic measurement of care provision and outcomes, and research needed to deliver care improvement for children with paediatric feeding disorder
Adequacy of health message tailoring for ethnic minorities : Pasifika communities in Sydney, Australia, during COVID-19
No full textEthnic minorities, such as Pasifika, residing in high-income countries were at higher risk of COVID-19 infection during the pandemic. To understand the experiences of Pasifika, including message dissemination and barriers to tailored public health messaging during the pandemic, a qualitative study was undertaken, underpinned by Laswell's Model of Communication and Bandura's social cognitive theory with data collected using Pasifika methods. Pasifika adults (n = 65) were recruited across Sydney from July 2020 to March 2022. Health care professionals (HCP) (n = 17) employed by four local health districts (LHDs) and Pasifika community-based organizations delivering multicultural COVID-19-related work within the study catchment, were also recruited. Five themes were constructed from the data of: (i) prevailing fear and uncertainty over COVID-19 infection and losing employment; (ii) limited knowledge of government perpetuating distrust in Government as a benevolent source of information; (iii) faith and trust as priorities for health decision-making; (iv) 'Coconut wireless' - the role of family, friends and community in disseminating public health messages through word of mouth; and (v) limited health literacy affecting compliance with public health orders. Community members identified important messages and resources had not been sufficiently distributed. Most HCPs understood the necessity of grassroots-level engagement but reported existing approaches were inadequate to navigate challenges. These findings highlight the need for public health promotion and communication strategies that consider both the social and cultural determinants of health. We propose a 7-point checklist as a cultural appropriateness lens to assist the development and rating of existing or new health promotion messaging and resources
[In Press] Green media coverage and corporate green innovation
No full textWe examine the effect of media coverage of corporate environmental activities on corporate green innovation. Using a large sample of corporate news coverage over the period 2001–2019, we find a positive relationship between green media coverage and the green innovation of a corporation but a negative one between nongreen media coverage and green innovation. These results are robust to a battery of sensitivity tests, including the instrumental approach and propensity score matching method. We examine and verify two well-documented general channels through which the media influences corporate behaviors, namely, the financial constraint mitigation and external governance. More importantly, we examine channels specifically related to green media coverage and find that green media coverage strengthens the effect of pressure imposed by the government and the public for green innovation. Taken together, our results suggest that the media plays a distinctive role in green innovation through its particular attention to the environment
Impact of industry 4.0 technologies on operations resilience : adverse effects of COVID-19 as a moderator
No full textIn the era of Industry 4.0, manufacturing firms are focused towards implementing a broad range of Industry 4.0 technologies and expect those technologies to shield them from disruptions. Rapid technology upgrades, adoption of new technologies and digitalised operations have been common during the COVID-19 pandemic, where remote working labour, skill shortages, supply shortages, and demand issues caused operations uncertainties. This study investigates the effects of Industry 4.0 technologies and incremental innovation on the operations resilience of Australian manufacturing firms operated under various COVID-19 challenges. Based on survey data collected from 117 manufacturing firms, it finds that Industry 4.0 capabilities lead to operations resilience only through incremental innovations and that COVID-19 effects moderate the relationship between Industry 4.0 capabilities and operations resilience. There was no empirical evidence for the moderating role of COVID-19 effects on the relationship between incremental innovation and operations resilience. Based on the findings, we argue that Industry 4.0 capabilities translate stronger into operations resilience for firms that experience substantial adverse effects than for those that experience lower negative effects. Our results confirm the benefits of manufacturing firms investing in a broad range of Industry 4.0 technologies to achieve operations resilience in highly disrupted environments where the survival of firms is threatened and the importance of developing capabilities for incremental innovation. Our findings assure managers of manufacturing firms of the benefits of technology investments and provide a rationale for those weighing alternatives to achieve operations resilience