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Free healthy breakfasts in primary schools: A cluster randomised controlled trial of a policy intervention in Wales, UK
Objective: The present study evaluated the impact of a national school programme of universal free healthy breakfast provision in Wales, UK.
Design: A cluster randomised controlled trial with repeated cross-sectional design and a 12-month follow-up. Primary outcomes were breakfast skipping, breakfast diet and episodic memory. Secondary outcomes were frequency of eating breakfast at home and at school, breakfast attitudes, rest-of-day diet and class behaviour.
Setting: Primary schools in nine local education authority areas.
Subjects: A total of 4350 students (aged 9–11 years) at baseline and 4472 at follow-up in 111 schools.
Results: Students in intervention schools reported significantly higher numbers of healthy food items consumed at breakfast and more positive attitudes towards breakfast eating at 12 months. Parents in intervention schools reported significantly higher rates of consumption of breakfast at school and correspondingly lower rates of breakfast consumption at home. No other significant differences were found.
Conclusions: The intervention did not reduce breakfast skipping; rather, pupils substituted breakfast at home for breakfast at school. However, there were improvements in children’s nutritional intake at breakfast time, if not the rest of the day, and more positive attitudes to breakfast, which may have implications for life-course dietary behaviours. There was no impact on episodic memory or classroom behaviour, which may require targeting breakfast skippers
Techno-economic and reliability assessment of solar water heaters in Australia based on Monte Carlo analysis
Monte Carlo analysis is used in this study to estimate the techno-economic benefits and reliabilities of solar water heaters. The study focuses on a product range manufactured by a local company in Australia. The historical data provided by the company forms the basis of this investigation. The inverse Weibull distribution function is a good match for representing the historical data in the model in terms of the number of failures per operating time for each component. The overall system reliability is determined as the sum of individual component failures during the product lifetime. The analysis is carried out for different system configurations using copper, stainless steel and glass-lined storage tanks. All the systems utilise flat plate collectors. The product with glass-lined storage tanks and electric boosters show a good overall reliability if systems are maintained. Based on the probability model, the variable maintenance costs of solar water heaters were estimated over the product lifetime. This together with capital expenditures and fuel charges are used to compute the specific price of hot water supply for different system configurations. Moreover, a sensitivity analysis is implemented to show the impact of auxiliary heating on the economic viability of the products. The results show that solar water heaters can offer significantly better long-term economic viability compared to conventional systems at moderate auxiliary energy consumptions
Erosional features as indicators of thrust fault activity (Nankai Trough, Japan)
A submarine channel system and basal ramps of a Quaternary mass-transport deposit (MTD) are shown to represent thrust fault activity in the Nankai accretionary wedge. Variations in channel bed slope, height and width of submarine channels and gullies indicate uplift and sediment bypass seaward from a margin-dominating out-of-sequence thrust, the megasplay fault (MSF), at < 1.67-1.46 Ma. Between ~ 1.05 and 0.85 Ma, a younger mass-transport deposit (MTD 6) was detached at different depths. Demonstrating the significant deformation observed in the study area, the direction of transport of MTD 6 differs 30o-45o from the strike of scarps and ramps at its base, which are parallel to the structural contours of thrust anticlines underneath. This character contrasts to the geometries frequently documented in frontally-emergent submarine landslides. In parallel, oblique basal ramps form significant boundaries between zones of MTD 6 with distinct acoustic and, suggestively, petrophysical properties. As a result of this study, we postulate that developed channel systems can erode the upper continental slope and lead to bypass of substantial volumes of sediment to distal parts of accretionary wedges. This process bears the potential of generating periods of more intense thrust-wedge deformation, at least locally, than those predicted by mathematical and physical models based on present-day taper geometries. On a regional scale, the observations in this paper are important as they indicate a more diffuse distribution of deformation in the Nankai accretionary wedge than previously assumed for the MSF region
Spin instabilities and quantum phase transitions in integral and fractional quantum Hall states
The inter-Landau-level spin excitations of quantum Hall states at filling
factors nu=2 and 4/3 are investigated by exact numerical diagonalization for
the situation in which the cyclotron (hbar*omega_c) and Zeeman (E_Z) splittings
are comparable. The relevant quasiparticles and their interactions are studied,
including stable spin wave and skyrmion bound states. For nu=2, a spin
instability at a finite value of epsilon=hbar*omega_c-E_Z leads to an abrupt
paramagnetic to ferromagnetic transition, in agreement with the mean-field
approximation. However, for nu=4/3 a new and unexpected quantum phase
transition is found which involves a gradual change from paramagnetic to
ferromagnetic occupancy of the partially filled Landau level as epsilon is
decreased.Comment: 4 pages, 5 figures, submitted to Phys.Rev.Let
Do stronger school smoking policies make a difference? Analysis of the health behaviour in school-aged children survey
Background: Associations of the strength of school smoking policies with cigarette, e-cigarette and cannabis use in Wales were examined. Methods: Nationally representative cross-sectional survey of pupils aged 11–16 years (N=7376) in Wales. Senior management team members from 67 schools completed questionnaires about school smoking policies, substance use education and tobacco cessation initiatives. Multi-level, logistic regression analyses investigated self-reported cigarette, e-cigarette and cannabis use, for all students and those aged 15–16 years. Results: Prevalence of current smoking, e-cigarette use and cannabis use in the past month were 5.3%, 11.5% and 2.9%, respectively. Of schools that provided details about smoking policies (66/67), 39.4% were strong (written policy applied to everyone in all locations), 43.9% were moderate (written policy not applied to everyone in all locations) and 16.7% had no written policy. There was no evidence of an association of school smoking policies with pupils’ tobacco or e-cigarette use. However, students from schools with a moderate policy [OR = 0.47; 95% (confidence interval) CI: 0.26–0.84] were less likely to have used cannabis in the past month compared to schools with no written policy. This trend was stronger for students aged 15–16 years (moderate policy: OR = 0.42; 95% CI: 0.22–0.80; strong policy: OR = 0.45; 95% CI: 0.23–0.87). Conclusions: School smoking policies may exert less influence on young people’s smoking behaviours than they did during times of higher adolescent smoking prevalence. Longitudinal studies are needed to examine the potential influence of school smoking policies on cannabis use and mechanisms explaining this associatio
Factors associated with changes of state of foot conformation and lameness in a flock of sheep
The aim of this research was to investigate transitions between foot conformation, lameness and footrot in sheep. Data came from one lowland flock of approximately 700 ewes studied for 18 months. Multilevel multistate analyses of transitions between good and poor foot conformation states in ewes, and lame and non-lame states in ewes and lambs were conducted. Key results were that the longer sheep had feet in good conformation, the more likely they were to stay in this state; similarly, the longer a ewe was not lame the more likely she was not to become lame. Ewes with poor foot conformation were more likely to become lame (OR: 1.83 (1.24-2.67)) and to be > 4 years (OR: 1.50(1.09-2.05)). Ewes with footrot were less likely to move to good foot conformation (OR: 0.48 (0.31-0.75)) and were more likely to become lame (OR: 3.81(2.60-5.59)). Ewes lame for > 4 days and not treated with parenteral antibacterials had a higher risk of developing (OR: 2.00 (1.08-3.61)), or remaining in (OR: 0.49 (0.29-0.95)) poor foot conformation compared with ewes never lame. Treatment of ewes lame with footrot with parenteral antibacterials increased the probability of transition from a lame to a non-lame state (OR: 1.46 (1.05-2.02)) and these ewes, even if lame for > 4 days, were not more likely to develop poor foot conformation. The risk of a ewe becoming lame increased when at least one of her offspring was lame (OR: 2.03 (1.42-2.92)) and when the prevalence of lameness in the group was ≥ 5% (OR: 1.42 (1.06-1.92)). Lambs were at increased risk of becoming lame when they were male (OR: 1.42 (1.01-2.01)), single (OR: 1.86 (1.34-2.59)) or had a lame dam or sibling (OR: 3.10 (1.81-5.32)). There were no explanatory variables associated with lambs recovering from lameness. We conclude that poor foot conformation in ewes increases the susceptibility of ewes to become lame and that this can arise from untreated footrot. Treatment of ewes lame with footrot with parenteral antibacterials leads to recovery from lameness and prevents or resolves poor foot conformation which then reduces the susceptibility to further lameness with footrot
Latin diagnosis : time to let go
Article 36.1 of the International code of botanical nomenclature (McNeill & al., 2006) requires that, as from 1 January
1935, all names of new plant taxa (algae and fossils excepted) can be validly published only if they are accompanied by a Latin
description or diagnosis or by a reference to an effectively published Latin diagnosis or description. Although several past Nomenclature
Section meetings have voted on proposals to have this requirement lifted, the liberation of plant nomenclature, and
by implication plant taxonomy, from this impediment remains elusive. We argue that the Latin requirement must be removed
now as it represents a relict that does not serve the purposes for which it was originally intended. Previous proposals to delete
the requirement of a Latin description or diagnosis for the valid publication of a plant name have all had strings attached. We
propose (Figueiredo & al. in Taxon 59: 659–660, this issue) that, as from the effective date of the Melbourne Code (a suitable
date after the Melbourne Congress), a diagnosis or description in any language would suffice to effect valid publication of a
plant name, the algae and fossils excepted, provided all of the other provisions for valid publication have been satisfied
Who amends the international code of botanical nomenclature? A response to Applequist & al. (2010)
We maintain that a review of the way in which votes that can be cast to influence the amendment of the International
Code of Botanical Nomenclature (ICBN) are allocated is overdue. Although there will no doubt be resistance to proposed
changes that may emanate from such a review, a more representative system of vote allocation to herbaria, among other things,
will considerably enhance the credibility and robustness of the voting system. A rebuttal addressing two criteria we suggest
as examples of what could be used as part of a review to make the voting system more representative was recently published
by Applequist & al. It is regrettable that in the face of unambiguous statistics that show the inadequacy of the current ICBN
amendment voting system, the need for change is not embraced with due urgency. A fear of power sharing and decentralization
may well be the root cause.http://www.botanik.univie.ac.at/iapt/s_taxon.phpnf201
Universal Continuous Variable Quantum Computation in the Micromaser
We present universal continuous variable quantum computation (CVQC) in the
micromaser. With a brief history as motivation we present the background theory
and define universal CVQC. We then show how to generate a set of operations in
the micromaser which can be used to achieve universal CVQC. It then follows
that the micromaser is a potential architecture for CVQC but our proof is
easily adaptable to other potential physical systems.Comment: 12 pages, 4 figures, accepted for a presentation at the 9th
International Conference on Unconventional Computation (UC10) and LNCS
proceedings
Spatial repellents: from discovery and development to evidence based validation
International public health workers are challenged by a burden of arthropod-borne disease that remains elevated despite best efforts in control programmes. With this challenge comes the opportunity to develop novel vector control paradigms to guide product development and programme implementation. The role of vector behaviour modification in disease control was first highlighted several decades ago but has received limited attention within the public health community. This paper presents current evidence highlighting the value of sub-lethal agents, specifically spatial repellents, and their use in global health, and identifies the primary challenges towards establishing a clearly defined and recommended role for spatial repellent products in disease control
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