1,160 research outputs found

    Fermi Surface Nesting and the Origin of the Charge Density Wave in NbSe2_2

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    We use highly accurate density functional calculations to study the band structure and Fermi surfaces of NbSe2. We calculate the real part of the non-interacting susceptibility, Re chi_0(q), which is the relevant quantity for a charge density wave (CDW) instability and the imaginary part, Im chi_0(q), which directly shows Fermi surface (FS) nesting. We show that there are very weak peaks in Re chi_0(q) near the CDW wave vector, but that no such peaks are visible in Im chi_0(q), definitively eliminating FS nesting as a factor in CDW formation. Because the peak in Re chi_0(q) is broad and shallow, it is unlikely to be the direct cause of the CDW instability. We briefly address the possibility that electron-electron interactions (local field effects) produce additional structure in the total (renormalized) susceptibility, and we discuss the role of electron-ion matrix elements.Comment: Replacement of Table II values, minor changes to tex

    Pictorial scale of perceived water competence (PSPWC) testing manual

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    The Early Years Special Interest Group have completed a technical publication, ‘Pictorial Scale of Perceived Water Competence (PSPWC) Testing Manual’. This publication is the first to specifically focus and develop an assessment tool appropriate for young children aged 4 – 8 years old. It aims to address the following specific needs 1) to be accessible to this young age range, 2) to be suitable for children of different swimming levels, 3) cover all the aquatic fundamentals – water entry, breath control, buoyancy, balance, propulsion, immersion, water exit, gliding and vision. The idea to develop the PSPWC started during the Early Years Special Interest Group meeting at Laramie 2016 AIESEP, which then developed into a larger group of experts in order to develop and present the assessment tool. A four year process of critical analysis, preliminary face-validity, face-validity and content validity were completed in the development of each version of the PSPWC until the final testing manual was completed. Within the testing manual all aquatic skills and test items are represented through visual methodologies of drawings by a professional illustrator. In order to engage young children’s interests and to keep their attention to facilitate their understanding and to obtain more meaningful responses. The testing manual includes 3 level progressions for each situation, skill or test item, level 1 = “not able to do the skill”; level 2 = “skill in progress” and level 3 = “able to do the skill. The 3 level progression was developed as the expert group considered it more appropriate to have a process orientated scale showing a child’s developmental progression. The PSPWC can be applied for use in children (measurement of their own perceived water competence), in parents (measurements of their perception of children’s water competence) and/or in teachers (measurement of their perception of pupils’ / students’ water competence. The testing manual is accessible to all through open access publication

    Face and content validity of the pictorial scale of perceived water competence in young children

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    An international group of experts have developed a pictorial tool to measure perceived water competence for children aged from 5 to 8 years old: the Pictorial Scale of Perceived Water Competence (PSPWC). The aim of the present study was to verify the validity of this tool. In the first part of the study, 120 children were interviewed to investigate face validity of the PSPWC to ensure that all pictorial items were understandable. In the second part of the study, 13 scientific and/or pedagogical international experts were invited to assess the tool's content validity via an online survey. Face validity results revealed that children were able to understand and sequence correctly the aquatic situations in 92% of the cases. The average Content Validity Index (CVI) of the PSPWC ranged from 0.88 to 0.95, showing acceptable content validity. Feedback from experts and children resulted in a major improvement of the "exit water" situation and minor improvements concerning some other items. Experts confirmed that the PSPWC was globally appropriate for different countries and cultures, except for the situation "water entry by slide" which was not considered usual practice in some countries. The PSPWC opens up to new fields of research; useful both for the prevention of drowning and for the support of children's aquatic education

    Differences between young children's actual, self-perceived and parent-perceived aquatic skills

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    As drowning is a leading cause of unintentional injury/death in children worldwide, perceptions of their actual aquatic skills are of critical importance. Children’s self perceptions may influence the risks they take, and parental perceptions may influence the degree of supervision deemed to be necessary for children in and around water. Accordingly, we examined the differences between young children’s actual, self-perceived and parent-perceived aquatic skills. Using a three-way repeated measures ANCOVA, we analyzed data from 134 child-parent dyads (56.0% boys; M age ÂŒ 7.1, SD ÂŒ 1.1 years; and 71.6% mothers). We measured self and parental perceptions of the child’s aquatic skills with the ‘Pictorial Scale of Perceived Water Competence’ (PSPWC), and we applied the exact same 17 test items of the PSPWC to assess the child’s actual aquatic skill level in the water. Controlling for years of swimming school experience, within-subject differences between the total scores on the ‘Actual Aquatic Skills Test’ (AAST) and both the child- and parentcompleted PSPWC indicated lower than actual estimates of the children’s aquatic skill level. The degree of disagreement against the AAST was more pronounced in parents than in 6-7 year-old children but was similar between parents and 8-9 yearold children, with these patterns being evident regardless of the children’s sex. Our study contributes to an ongoing validation of the PSPWC and represents a key advance in assessing and comparing children’s actual and perceived aquatic skill competence, using perfectly aligned instruments. Future research and practice might explore children’s actual aquatic skills in different contexts (e.g., open water), include perspectives of non-parent caregivers and assess perceived and actual water competence across development

    Consumer credit information systems: A critical review of the literature. Too little attention paid by lawyers?

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    This paper reviews the existing literature on consumer credit reporting, the most extensively used instrument to overcome information asymmetry and adverse selection problems in credit markets. Despite the copious literature in economics and some research in regulatory policy, the legal community has paid almost no attention to the legal framework of consumer credit information systems, especially within the context of the European Union. Studies on the topic, however, seem particularly relevant in view of the establishment of a single market for consumer credit. This article ultimately calls for further legal research to address consumer protection concerns and inform future legislation

    Emerging dietary patterns: impact on child health

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    What we eat today and how we decide to produce sufficient food to meet both demand and nutritional requirements will determine the availability, diversity and quality of diets for future generations. Acceptability and normalisation of new dietary patterns must be prioritised to the same extent as education on environmental sustainability and health, because these are important social levers. They can help to reduce the psychosocial barriers and anxieties often connected to the behaviour changes that are needed to transition away from the traditional Western eating habits that are now increasingly subject to critical scrutiny. Without understanding the motivations and facilitators to change eating habits (and then designing and amplifying solutions which make those changes attractive and compelling in the modern world) positive changes to young people’s health and their environment through better food will not come quickly enough to halt potentially catastrophic consequences for people and planet. Changing consumption is seen by experts as the most powerful lever compared to food waste reduction or more efficient food production methods and technological solutions. There is simply not enough on Earth to sustain the increase of intensification required to continue feeding a global population on its current trajectory with a diet so rich in animal produce. However, radical behaviour modification is challenging and therefore cross-sector, bold and perhaps unorthodox leadership is necessary to inspire alteration in the food system, which will have a knock-on effect in terms of changing food environments and therefore food perceptions, narratives and behaviours. There are no ‘quick fix’ solutions, but what is undeniable is that populations can only make effective shifts in dietary patterns if government and the food industry help them to make those changes. This requires budgetary investment in public health information and the implementation of policies that promote ways to eat healthily that are also affordable and environmentally sustainable. The aim is to offer food that tastes as good as it can be made to look so that uptake is maximised and the benefits are cumulative. The inevitable upheaval incurred by making any alteration to entrenched patterns of consumption that have been centuries in the making should not be underestimated, but carrying on as before is no longer credible nor desirable. The aim is to offer ‘nutritious’ food. ‘If we don’t take action, the collapse of our civilisations and the extinction of much of the natural world is on the horizon’ Sir David Attenborough. This Report is our initial contribution to a conversation that has only just begun.It is unlikely to be the last

    Indigenous family violence : an attempt to understand the problems and inform appropriate and effective responses to criminal justice system intervention

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    Whilst high levels of concern about the prevalence of family violence within Indigenous communities have long been expressed, progress in the development of evidence-based intervention programs for known perpetrators has been slow. This review of the literature aims to provide a resource for practitioners who work in this area, and a framework from within which culturally specific violence prevention programs can be developed and delivered. It is suggested that effective responses to Indigenous family violence need to be informed by culturally informed models of violence, and that significant work is needed to develop interventions that successfully manage the risk of perpetrators of family violence committing further offences.<br /

    A repurposing strategy for Hsp90 inhibitors demonstrates their potency against filarial nematodes

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    Novel drugs are required for the elimination of infections caused by filarial worms, as most commonly used drugs largely target the microfilariae or first stage larvae of these infections. Previous studies, conducted in vitro, have shown that inhibition of Hsp90 kills adult Brugia pahangi. As numerous small molecule inhibitors of Hsp90 have been developed for use in cancer chemotherapy, we tested the activity of several novel Hsp90 inhibitors in a fluorescence polarization assay and against microfilariae and adult worms of Brugia in vitro. The results from all three assays correlated reasonably well and one particular compound, NVP-AUY922, was shown to be particularly active, inhibiting Mf output from female worms at concentrations as low as 5.0 nanomolar after 6 days exposure to drug. NVP-AUY922 was also active on adult worms after a short 24 h exposure to drug. Based on these in vitro data, NVP-AUY922 was tested in vivo in a mouse model and was shown to significantly reduce the recovery of both adult worms and microfilariae. These studies provide proof of principle that the repurposing of currently available Hsp90 inhibitors may have potential for the development of novel agents with macrofilaricidal properties
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