Child social relations and gender

This thesis reports six studies investigating the ways in which children experience themselves as gendered beings. The first two studies evaluate the theories of gender development proposed by exponents of both cognitive-developmental, and social learning theory, schools of thought. The results indicate that neither approach, with their emphasis on cognition at the exclusion of behaviour, or vice versa, provide sufficient explanation of the child-gender interface. In studies three and four, childrens' experience of gender is not located within their cognition or behaviour, but within their social relations. Thus in each of these studies children are exposed to controlled contextual changes, eg. sex of interacting partner or gender-appropriateness of toys given to play with, to investigate the strategies boys and girls use to maintain relationships between them. Results suggest that two relational strategies, person-centred and object-centred, are employed by the children, and that their use is related to gender. Furthermore, it is indicated that such strategies are affected by context, with some contexts affording the use of particular strategies. The fifth study provides four detailed case-studies, set against a major contextual change in childrens' social relations; the transition from nursery into full-time education. The material presented indicates that changes are brought about in the child's experience and practice of gender as a result of this transition. The final study of the thesis explores the child's own awareness of the transition they have been through and the changes this has wrought upon them. Thus the research presented in this thesis argues for a dynamic model of gender; one in which the child's experience of theirself as a gendered being is clearly located within their social relation

Paper Session II-B - Integrated Risk System

The International Space Station ISS is a complex system technically and programmatically. The Space Station must support a wide range of payloads and missions. It must be launched in many launch packages and safely assembled and operated in the harsh space environment. It is being designed and manufactured by many organizations, including the prime contractor, subcontractors, the NASA institution, and international partners. Finally, the Station has multiple customers, (e.g., the Administration, Congress, users, public, etc.) with contrasting needs and constraints. It is thus ISS strategy to proactively and systematically manage risk to help ensure Program success. The risk management process provides to the program systematic methods for identifying, analyzing, abating, and communicating risks

Can changing the physical environment promote walking and cycling? A systematic review of what works and how

This is the final version. Available on open access from Elsevier via the DOI in this recordEnvironmental changes aimed at encouraging walking or cycling may promote activity and improve health, but evidence suggests small or inconsistent effects in practice. Understanding how an intervention works might help explain the effects observed and provide guidance about generalisability. We therefore aimed to review the literature on the effects of this type of intervention and to understand how and why these may or may not be effective. We searched eight electronic databases for existing systematic reviews and mined these for evaluative studies of physical environmental changes and assessed changes in walking, cycling or physical activity. We then searched for related sources including quantitative or qualitative studies, policy documents or reports. We extracted information on the evidence for effects (‘estimation’), contexts and mechanisms (‘explanation’) and assessed credibility, and synthesised material narratively. We identified 13 evaluations of interventions specifically targeting walking and cycling and used 46 related sources. 70% (n = 9 evaluations) scored 3 or less on the credibility criteria for effectiveness. 6 reported significant positive effects, but higher quality evaluations were more likely to report positive effects. Only two studies provided rich evidence of mechanisms. We identified three common resources that interventions provide to promote walking and cycling: (i) improving accessibility and connectivity; (ii) improving traffic and personal safety; and (iii) improving the experience of walking and cycling. The most effective interventions appeared to target accessibility and safety in both supportive and unsupportive contexts. Although the evidence base was relatively limited, we were able to understand the role of context in the success of interventions. Researchers and policy makers should consider the context and mechanisms which might operate before evaluating and implementing interventions.Medical Research Council (MRC)National Institute for Health Research (NIHR

Poor intestinal permeability in mildly stunted Nepali children: associations with weaning practices and Giardia lamblia infection

Studies in the Gambia, using the lactulose-mannitol dual-sugar intestinal permeability test (lactulose:mannitol ratio) as a non-invasive way of investigating mucosal damage, have shown that food malabsorption is significantly associated with early growth retardation. In this cross-sectional study, 210 poor urban Nepali children, 0-60 months old, were recruited and measured for height or length and weight, 167 were examined for intestinal permeability and 173 for parasite infection. Weaning and morbidity data were collected from 172 caretakers. Children were mildly stunted (mean height-for-age z-score -1·45) and underweight (mean weight-for-age z-score -1·62). The lactulose:mannitol ratio (0·26) was poorer than that of UK children (0·12), but similar to that found in Bengali children of the same age (0·24). Two stages of weaning, the onset supplementary feeding (6 months) and the cessation of breast-feeding (23 months), were shown to have differential impact. In children currently breast-feeding, the duration of supplementation was negatively related to lactose (P<0·001) and lactose:lactulose values (P<0·0001), indicating lactose maldigestion. In children who had ceased breast-feeding, a longer period of lactation was associated with poorer intestinal permeability (P=0·031), and poorer height-for-age (P=0·024), which was an unexpected result. No significant relationships were found between intestinal permeability and growth, or with morbidity and helminth infection, except in children with Giardia lamblia who had worse lactulose:mannitol ratios than those without (0·43 v. 0·25 respectively, P=0·014). It is likely that insults to the gut (e.g. Giardia) and challenges to the immune system (weaning) have a different impact in early and late infancy

Foliar Expression of Candidate Genes Involved in Condensed Tannin Biosynthesis in White Clover (\u3cem\u3eTrifolium Repens\u3c/em\u3e)

Bloat disease in cattle and sheep is caused by the rapid microbial degradation of protein-rich fodder in the rumen. This leads to the production of protein foams that trap gases, causing bloat, a condition that is often fatal to livestock and costly to farmers. Condensed tannins (CTs) are phenolic polymers produced by the phenylpropanoid pathway of plants (Figure 1). CTs bind to proteins under acidic to neutral conditions, such as those present in the rumen, slowing their breakdown. A diet with a CT content of between 2% and 4% by dry weight, which is provided by some pasture legumes (e.g. Lotus corniculatus), protects livestock against bloat and improves the absorption of amino acids from the diet. White clover (Trifolium repens L.), a protein rich legume widely used in temperate regions, has virtually no CTs in leaves, although they are present in flowers

Stellar atmosphere parameters with MAx, a MAssive compression of x^2 for spectral fitting

MAx is a new tool to estimate parameters from stellar spectra. It is based on the maximum likelihood method, with the likelihood compressed in a way that the information stored in the spectral fluxes is conserved. The compressed data are given by the size of the number of parameters, rather than by the number of flux points. The optimum speed-up reached by the compression is the ratio of the data set to the number of parameters. The method has been tested on a sample of low-resolution spectra from the Sloan Extension for Galactic Understanding and Exploration (SEGUE) survey for the estimate of metallicity, effective temperature and surface gravity, with accuracies of 0.24 dex, 130K and 0.5 dex, respectively. Our stellar parameters and those recovered by the SEGUE Stellar Parameter Pipeline agree reasonably well. A small sample of high-resolution VLT-UVES spectra were also used to test the method and the results have been compared to a more classical approach. The speed and multi-resolution capability of MAx combined with its performance compared with other methods indicates that it will be a useful tool for the analysis of upcoming spectral surveys.Comment: 17 pages, 10 figures, minor changes after the chief language editor. A&A, in pres

The Complete Star Formation History of the Universe

The determination of the star-formation history of the Universe is a key goal of modern cosmology, as it is crucial to our understanding of how structure in the Universe forms and evolves. A picture has built up over recent years, piece-by-piece, by observing young stars in distant galaxies at different times in the past. These studies indicated that the stellar birthrate peaked some 8 billion years ago, and then declined by a factor of around ten to its present value. Here we report on a new study which obtains the complete star formation history by analysing the fossil record of the stellar populations of 96545 nearby galaxies. Broadly, our results support those derived from high-redshift galaxies elsewhere in the Universe. We find, however, that the peak of star formation was more recent - around 5 billion years ago. Our study also shows that the bigger the stellar mass of the galaxy, the earlier the stars were formed. This striking result indicates a very different formation history for high- and low-mass formation.Comment: Accepted by Nature. Press embargo until publishe