Perceptions of healthy eating and physical activity in an ethnically diverse sample of young children and their parents: the DEAL prevention of obesity study

Background: Ethnicity is a consistent correlate of obesity; however, little is known about the perceptions and beliefs that may influence engagement with obesity prevention programmes among ethnic minority children. Barriers to (and facilitators of) healthy lifestyles were examined in the qualitative arm of the London (UK) DiEt and Active Living (DEAL) study. Methods: Children aged 8–13 years and their parents, from diverse ethnic groups, were recruited through schools and through places of worship. Thirteen focus group sessions were held with 70 children (n = 39 girls) and eight focus groups and five interviews with 43 parents (n = 34 mothers). Results: Across ethnic groups, dislike of school meals, lack of knowledge of physical activity guidelines for children and negativity towards physical education at school among girls, potentially hindered healthy living. Issues relating to families' wider neighbourhoods (e.g. fast food outlets; lack of safety) illustrated child and parental concerns that environments could thwart intentions for healthy eating and activity. By contrast, there was general awareness of key dietary messages and an emphasis on dietary variety and balance. For ethnic minorities, places of worship were key focal points for social support. Discourse around the retention of traditional practices, family roles and responsibilities, and religion highlighted both potential facilitators (e.g. the importance of family meals) and barriers (reliance on convenience stores for traditional foods). Socio-economic circumstances intersected with key themes, within and between ethnic groups. Conclusions: Several barriers to (and facilitators of) healthy lifestyles were common across ethnic groups. Diversity of cultural frameworks not only were more nuanced, but also shaped lifestyles for minority children.</p

High frequency diffraction of an electromagnetic plane wave by an imperfectly conducting rectangular cylinder

Copyright @ 2011 IEEEWe shall consider the the problem of determining the scattered far wave field produced when a plane E-polarized wave is incident on an imperfectly conducting rectangular cylinder. By using the the uniform asymptotic solution for the problem of the diffraction of a plane wave by a right-angled impedance wedge, in conjunction with Keller's method, the a high frequency far field solution to the problem is given

Estimating specific surface area of fine stream bed sediments from geochemistry

Specific surface area (SSA) of headwater stream bed sediments is a fundamental property which determines the nature of sediment surface reactions and influences ecosystem-level, biological processes. Measurements of SSA – commonly undertaken by BET nitrogen adsorption – are relatively costly in terms of instrumentation and operator time. A novel approach is presented for estimating fine (2.5 mg kg−1), four elements were identified as significant predictors of SSA (ordered by decreasing predictive power): V > Ca > Al > Rb. The optimum model from these four elements accounted for 73% of the variation in bed sediment SSA (range 6–46 m2 g−1) with a root mean squared error of prediction – based on leave-one-out cross-validation – of 6.3 m2 g−1. It is believed that V is the most significant predictor because its concentration is strongly correlated both with the quantity of Fe-oxides and clay minerals in the stream bed sediments, which dominate sediment SSA. Sample heterogeneity in SSA – based on triplicate measurements of sub-samples – was a substantial source of variation (standard error = 2.2 m2 g−1) which cannot be accounted for in the regression model. The model was used to estimate bed sediment SSA at the other 1792 sites and at 30 duplicate sites where an extra sediment sample had been collected, 25 m from the original site. By delineating sub-catchments for the headwater sediment sites only those sub-catchments were selected with a dominant (>50% of the sub-catchment area) bedrock formation and land use type; the bedrock and land use classes accounted for 39% and 7% of the variation in bed sediment SSA, respectively. Variation in estimated, fine bed sediment SSA from the paired, duplicate sediment sites was small (2.7 m2 g−1), showing that local variation in SSA at stream sites is modest when compared to that between catchments. How the approach might be applied in other environments and its potential limitations are discussed

Exit plane H2O concentration measurements correlated with OH PLIF near-injector mixing measurements for scramjet flows

Mixing and combusting high enthalpy flows, similar to those encountered in scramjet engines, were investigated using a shock tunnel to produce the flow in conjunction with non-intrusive optical diagnostics which monitored the performance of two injector configurations. The shock tunnel is configured to produce Mach 3 flow and stagnation enthalpies corresponding to flight equivalent Mach numbers between 7 and 11. A pulsed hydrogen injection capability and interchangeable injector blocks provide a means of examining high speed, high enthalpy reacting flows. Planar laser induced fluorescence (PLIF) of OH molecules in the near injector region produced images which show the combusting and mixing zones for the reacting flow. Line-of-sight exit plane measurement of water concentration and temperature were used to provide a unique method of monitoring exit plane products. These results demonstrated that a velocity matched axial injection system produced a fuel jet that lifted off the floor of the duct. Mixing was observed to increase for this system as a velocity mismatch was introduced. Comparison of exit plane water concentrations for a wall jet injection system and a velocity matched injection system indicated similar mixing performance but an accurate pressure measurement is necessary to further validate the result. In addition, exit plane measurements indicated an approximate steady-state condition was achieved during the 1 to 2 ms test times

Intermittent Small Baseline Subset (ISBAS) monitoring of land covers unfavourable for conventional C-band InSAR: proof-of-concept for peatland environments in North Wales, UK

This paper provides a proof-of-concept for the use of the new Intermittent Small Baseline Subset (ISBAS) approach to study ground elevation changes in areas of peat and organic soils in north Wales, which are generally, unfavourable for conventional C-band interferometric applications. A stack of 53 ERS-1/2 C-band SAR scenes acquired between 1993 and 2000 in descending mode was processed with both the standard low-pass SBAS method and ISBAS. The latter revealed exceptional improvements in the coverage of ground motion solutions with respect to the standard approach. The number of identified coherent and intermittently coherent pixels increased by a factor of 26 with respect to the SBAS solution, and extended the coverage of results across unfavourable land covers, particularly for coniferous woodland, bog, acid grassland and heather. The greatest increase was achieved over coniferous woodland, which showed ISBAS/SBAS pixel density ratios above 300. Despite the intermittent nature of the ISBAS solutions, ISBAS provided velocity standard errors generally below 1-1.5 mm/yr, thus preserving good quality of the estimated ground motion rates

High-temporal Resolution Sediment Fingerprinting in the River Wensum Demonstration Test Catchment, UK: A Bayesian Approach

A high-temporal resolution fluvial sediment source apportionment model, set within an empirical Bayesian framework, is presented for the River Wensum Demonstration Test Catchment (DTC), UK. Direct X-ray fluorescence (XRF) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis of sediment covered filter papers were used in conjunction with ISCO automatic water samplers to monitor suspended particulate matter (SPM) geochemistry at high-temporal resolution throughout the progression of five heavy precipitation events during 2012-2013. Exploiting the spatial and temporal variation in four potential sediment source areas and SPM geochemistry respectively, we are able to apportion sediment contributions from eroding stream channel banks, arable topsoils, damaged road verges and agricultural field drains at 60-120 minute resolution. For all monitored precipitation episodes, pre- and post-event conditions are dominated by elevated SPM calcium concentrations that indicate major sediment inputs from carbonate-rich subsurface sources. Conversely, precipitation events coincide with an increase in concentrations of clay-associated elements and a consequent increase in predicted contributions from surface sources. Employing a Gibbs sampling Markov Chain Monte-Carlo mixing model procedure has enabled full characterisation of both spatial geochemical variability and instrument precision to quantify uncertainty around posterior distributions. All model source apportionment estimates correspond favourably with understanding of the regional geology, analysis of hysteresis behaviour, and visual observations of catchment processes. The results presented here demonstrate how to directly analyse SPM trapped on filter papers by spectroscopy to yield the high-temporal resolution source apportionment estimates required by catchment managers to help mitigate the deleterious effects of land-to-river sediment transfer

The contribution of the Anglican church to education in the Cape

In his "Onderwys in Kaapland, 1652 - 1939", Dr. P.S. du Toit makes special references to the educational work of the Anglican Church, indicating that there is some contribution. This attitude has as its aim to expose more of the reef of which the outcrops receive attention by Dr. du Toit ... much can happen between 1807 and 1829, and some of what did is described in these pages. One of Dr. du Toit's interests is the effect of the attempt to make English and instruction in English the basis of all education. Chap. 1, p. 1

Combining Two Filter Paper-Based Analytical Methods to Monitor Temporal Variations in Fluvial Suspended Solid Properties

Many of the commonly used analytical techniques for assessing the properties of fluvial suspended solids are neither cost-effective nor time-efficient, making them prohibitive to long-term high-resolution monitoring.We propose a novel methodology utilising two types of spectroscopy which, when combined with automatic water samplers, can generate accurate, high-temporal resolution sediment property data, inexpensively and non-destructively, directly from sediment covered filter papers. A dual X-ray fluorescence spectroscopy (XRFS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) approach is developed to estimate concentrations for a range of elements (Al, Ca, Ce, Fe, K, Mg, Mn, Na, P, Si, Ti) and compounds (organic carbon, Aldithionate, Aloxalate, Fedithionate, and Feoxalate) within sediments trapped on quartz fibre filters at masses as low as 3 mg. Calibration models with small prediction errors are produced for a total of 16 elements and compounds for which the geochemical signal is demonstrated to be time stable enabling samples to be stored for several weeks prior to analysis. Spectral pre-processing methods are shown to enhance the reproducibility of results for some compounds, whilst corrections for sediment mass retention are derived, and the importance of filter paper selection and homogeneous sample preparation in minimising spectral interference are emphasized. The results presented here demonstrate the potential for a combined XRFS and DRIFTS analysis of sediment covered filter papers to be utilized under a range of in-stream hydrological conditions where there is an environmental requirement for high-resolution monitoring of suspended solid properties