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Morphologically controlled cobalt oxide nanoparticles for efficient oxygen evolution reaction
No full textElectrochemical water oxidation is one of the thrust areas of research today in solving energy and environmental issues. The morphological control in the synthesis of nanomaterials plays a crucial role in designing efficient electrocatalyst. In general, various synthetic parameters can direct the morphology of nanomaterials and often this is the main driving force for the electrocatalyst in tuning the rate of the oxygen evolution reaction (OER) for the electrochemical water-splitting. Here, a facile and cost-effective synthesis of spinel cobalt oxides (CoO) via a one-pot hydrothermal pathway with tunable morphology has been demonstrated. Different kinds of morphologies have been obtained by systematically varying the reaction time i.e. nanospheres, hexagon and nanocubes. Their catalytic activity has been explored towards OER in 1.0 M alkaline KOH solution. The catalyst CoO-24 h nanoparticles synthesized in 24 h reaction time shows the lowest overpotential (η) value of 296 mV at 10 mA cm current density, in comparison to that of other as-prepared catalysts i.e. CoO-pH9 (311 mV), CoO-12 h (337 mV), and CoO-6 h (342 mV) with reference to commercially available IrO (415 mV). Moreover, CoO-24 h sample shows the outstanding electrochemical stability up to 25 h time
The association between menstrual symptoms and hypertension among young women: A prospective longitudinal study
No full textObjectives: To investigate whether menstrual symptoms are associated with increased risk of hypertension among young women, and whether the relationship is bi-directional. Study design: We included 7729 women participating in the Australian Longitudinal Study on Women's Health, aged 22–27 years in 2000 and who were followed up every 3 years until 2015. Premenstrual syndrome, painful (dysmenorrhoea), heavy (menorrhagia), and irregular menstrual periods over the previous 12 months were self-reported and recorded as ‘never’, ‘rarely’, ‘sometimes’, or ‘often’. Questions regarding physician-diagnosed hypertension were asked, specifically for other than during pregnancy (defined as chronic hypertension) and during pregnancy (hypertensive disorder in pregnancy, HDP). Longitudinal data were analysed with generalised estimating equation time-lagged models to estimate relative risks (RRs) and 95 % confidence intervals (CI), adjusted for time-varying covariates. Mian outcome measures: Chronic hypertension, HDP, and menstrual disorders. Results: Over 15 years of follow-up, 757 women (9.8 %) reported having been diagnosed with chronic hypertension. Among 4473 parous women, 483 (10.8 %) reported a diagnosis of HDP. Women who often experienced heavy periods had an increased risk of incident chronic hypertension (RR 1.53, 1.13−2.09), compared with those who had not experienced heavy periods. We also found that women with chronic hypertension had an increased risk of incident heavy (RR 1.23, 1.02−1.50) and irregular periods (RR 1.42, 1.17−1.72). However, there was no apparent association between any menstrual symptoms and subsequent risk of HDP. Conclusions: The association between heavy periods (menorrhagia) and chronic hypertension may be bi-directional in young women. Chronic hypertension may also be associated with subsequent risk of irregular periods
Hot deformation behavior and processing map development of AZ110 alloy with and without addition of La-rich Mish Metal
No full textIn order to compare the workability of AZ110 alloy with and without addition of La-rich Mish Metal (MM), hot compression tests were performed on a Gleeble-3500D thermo-mechanical simulator at the deformation temperature range of 473−623 K and strain rate range of 0.001-1 s. The flow stress, constitutive relation, DRX kinetic model, processing map and microstructure characterization of the alloys were investigated. The results show that the flow stress is very sensitive to deformation temperature and strain rate, and the peak stress of AZ110LC (LC = La-rich MM) alloy is higher than that of AZ110 alloy. The hot deformation behavior of the alloys can be accurately predicted by the constitutive relations. The derived constitutive equations show that the calculated activation energy Q and stress exponent n for AZ110 alloy are higher than the calculated values of AZ110LC alloy. The analysis of DRX kinetic models show that the development of DRX in AZ110LC alloy is earlier than AZ110 alloy at the same deformation condition. The processing maps show that the workability of AZ110LC alloy is significantly more excellent than AZ110 alloy and the microstructures are in good agreement with the calculated results. The AZ110LC alloys can obtain complete DRX microstructure at high strain rate due to its higher stored energy and weak basal texture
Do objects fuel thyself? The relationship between objects and self-regulation
No full textIt has long been argued that people become attached to objects because objects help people to define, reflect, and communicate the self. In this article we consider whether objects not only help to ‘know thyself’ but also to ‘fuel thyself’. In other words, whether objects can contribute to self-regulation. We review past research to consider whether the functional and symbolic aspects of objects are found to promote self-regulation through enhanced recognition of and commitment to standards, monitoring, and capacity to change. We conclude by considering that people need to regulate their relationship with objects, in part because objects can successfully help people achieve basic needs. In this way, failure to regulate one's relationship to objects can contribute to problematic outcomes such as neglect, obesity, hoarding, and addiction
Electrochemical biofilm control by reconstructing microbial community in agricultural water distribution systems
No full textBiofilm causes considerable technical challenges in agricultural water distribution systems. Electrochemical treatment (ECT) is a potential technique for controlling biofilm in the systems. Given the limited information on how ECT performance changes of irrigation systems and microbial biofilm community shifts. In this study, the effect of anti-biofilm was assessed. Illumina Miseq high-throughput sequencing, combined with molecular ecological network analysis, were applied to detect the effects of ECT on attached biofilm microbial communities. We found that ECT effectively mitigated biofilm formation with the fixed-biofilm biomass reduced by 37.5 %–79.9 %. ECT significantly shifted the bacterial community structures in the biofilm, reduced the communities’ diversity, and changed the dominant species. Molecular ecological network analysis showed that the complexity and size of bacterial networks were destabilized under ECT and decreased the interactions among bacterial species. The reconstruction in bacterial community and networks were responsible for the decline in extracellular polymer substances and biofilm biomass. However, chlorine-resistant bacteria were found increased after ECT, and higher relative abundance and low biofilm removal was identified in continuous ECT as compared with intermittent ECT. These results aimed to highlight the opportunity for biofouling mitigation by ECT for irrigation systems, and reveal the potential anti-biofilm microbial mechanisms of ECT
Modelling folates reaction kinetics during cowpea seed germination in comparison with soaking
No full textFolate is a fundamental vitamin for metabolism in plants and humans. A modelling approach has been developed to characterize the reactivity of folates in cowpea seeds during germination at 30 °C, using a water-to-seed ratio of 1:1 (w/w). For this purpose, the concentrations of folic acid, 10-formylfolic acid, 5-methyltetrahydrofolate, 5-formyltetrahydrofolate and tetrahydrofolate were determined in seeds during germination times up to 96 h. Two reaction models were sequentially built and adjusted to experimental data to describe changes in concentration in cowpea seed during two germination phases: before 14 h and after 48 h. Results showed intense enzymatic interconversion of all folate vitamers into 5-methyltetrahydrofolate before 14 h of germination and high enzymatic production of 5-methyltetrahydrofolate, 5-formyltetrahydrofolate and tetrahydrofolate after 48 h of germination. This study suggests that a long germination process could be more beneficial than soaking to increase the production of bioavailable folates within the seed for human consumption
Enhanced removal of cephalexin and sulfadiazine in nitrifying membrane-aerated biofilm reactors
No full textNitrification process has been reported to be capable of degrading various pharmaceuticals due to the cometabolism of ammonia-oxidizing bacteria (AOB). The membrane aerated biofilm reactor (MABR) is an emerging configuration in wastewater treatment with advantages of high nitrification rate and low energy consumption. However, there are very few studies investigating the degradation of antibiotics at environmentally relevant levels in nitrifying MABR systems. In this study, the removal of two widely used antibiotics, cephalexin (CFX) and sulfadiazine (SDZ), was evaluated in two independent MABRs with nitrifying biofilms. The impacts of CFX and SDZ exposure on the nitrification performance and microbial community structure within biofilms were also investigated. The results showed that nitrifying biofilms were very efficient in removing CFX (94.6%) and SDZ (75.4%) with an initial concentration of 100 μg/L when hydraulic retention time (HRT) was 4 h in the reactors. When HRT decreased from 4 h to 3 h, the removal rates of CFX and SDZ increased significantly from 23.4 ± 1.0 μg/(L·h) and 18.7 ± 1.1 μg/(L·h), respectively, to 27.7 ± 1.3 μg/(L·h) (p＜0.01) and 20.8 ± 2.4 μg/(L·h) (p＜0.05), while the removal efficiencies decreased to 86.0% and 61.5%, respectively. Despite the exposure to CFX and SDZ, the nitrification performance was not affected, and microbial community structure within biofilms also remained relatively stable. This study shows that nitrifying MABR process is a promising option for the efficient removal of antibiotics from domestic wastewater
'From 'shameless' and 'worldly songs' to a vocal tribute' to 'Sing their Praises': the contested soundscapes of early modern poor children'
No full textMineral supply challenges during the COVID-19 pandemic suggest need for international supply security mechanism
No full textYarning about fetal alcohol spectrum disorder: outcomes of a community-based workshop
No full textIntroduction: There is a lack of neurodevelopmental assessment services in rural and remote locations in Australia that consider fetal alcohol spectrum disorder as a possible outcome.Methods: Eighty-seven participants attended a workshop to support community-based professional development and co-design of a novel assessment approach. Qualitative data collection included video recording of the workshop, and small group discussions, for which a narrative analysis was utilised. Quantitative data collection included self-report questionnaires to understand current community practices and three key constructs: practitioner knowledge, attitudes, and intentions for future practice.Results: The narrative analysis highlighted the ongoing impacts of colonisation, in terms of intergenerational trauma and alcohol use, experienced in the community today, and the potential high rates of fetal alcohol spectrum disorder. To address these issues, multiple strategies were discussed, including the recognition of First Nations knowledge and expertise and a focus on the next generation and community organisations working collaboratively. The pre-and post-questionnaires demonstrated that practitioners’ knowledge and attitudes were enhanced after attending the workshop, however practitioner intentions were not. The lack of significance for the intentions variable may have been due to the small number of available responses for that variable, in comparison to the other two constructs.Discussion: The current study identified key learnings from workshop facilitators and participants. The findings call attention to the importance of a co-design approach, where collaboration is vital to support the appropriate adaption of evidence-based practice to suit the local context
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