3,470 research outputs found
The measurement of household socio-economic position in tuberculosis prevalence surveys: a sensitivity analysis.
OBJECTIVE: To assess the robustness of socio-economic inequalities in tuberculosis (TB) prevalence surveys. DESIGN: Data were drawn from the TB prevalence survey conducted in Lusaka Province, Zambia, in 2005-2006. We compared TB socio-economic inequalities measured through an asset-based index (Index 0) using principal component analysis (PCA) with those observed using three alternative indices: Index 1 and Index 2 accounted respectively for the biases resulting from the inclusion of urban assets and food-related variables in Index 0. Index 3 was built using regression-based analysis instead of PCA to account for the effect of using a different assets weighting strategy. RESULTS: Household socio-economic position (SEP) was significantly associated with prevalent TB, regardless of the index used; however, the magnitude of inequalities did vary across indices. A strong association was found for Index 2, suggesting that the exclusion of food-related variables did not reduce the extent of association between SEP and prevalent TB. The weakest association was found for Index 1, indicating that the exclusion of urban assets did not lead to higher extent of TB inequalities. CONCLUSION: TB socio-economic inequalities seem to be robust to the choice of SEP indicator. The epidemiological meaning of the different extent of TB inequalities is unclear. Further studies are needed to confirm our conclusions
The role of dieting, happiness with appearance, self-esteem, and bullying in the relationship between mental health and body-mass index among UK adolescents: a longitudinal analysis of the Millennium Cohort Study.
BACKGROUND: Mental illness and obesity are among the biggest challenges to population health, they are linked, and may be modifiable during adolescence. We aimed to determine intervening pathways between mental health and BMI z-score symptoms across adolescence. METHODS: In this longitudinal cohort study, we used path models to examine self-reported dieting, happiness with appearance, self-esteem and bullying at 14 years as potential mediators of the cross-lagged relationship between mental health (via the Strengths and Difficulties Questionnaire) and Body Mass Index (BMI) z-score at 11 and 17 years by sex in the UK Millennium Cohort Study, a prospective cohort study of 18,818 children born in the UK between September 1st, 2000, and January 31st, 2002. Full, incomplete data on all singleton children still participating in the study by age 11 years were analysed in GSEM via maximum likelihood estimation (NÂ =Â 12,450). FINDINGS: We found happiness with appearance and self-esteem, but not dieting or bullying, mediated the relationship between BMI age 11 and mental health age 17. Each increase in BMI z-score at 11 years was associated with 0.12 increase for boys and a 0.19 increase for girls in scores of unhappiness with appearance (boys: b 0.12, 95% C.I.; girls b 0.19, C.I. 0.14 to 0.23) and a 16% increase for boys and a 22% increase for girls in odds of low self-esteem (boys OR 1.16, 95% C.I. 1.07 to 1.26; girls: OR 1.22, 95% C.I. 1.15 to 1.30) at 14 years. In turn, for both boys and girls, being unhappy with appearance and low self-esteem at 14 years were associated with a greater likelihood of emotional and externalizing symptoms at 17 years. INTERPRETATION: Early prevention strategies to encourage healthy physical and mental development of children need to focus on the promotion of positive body-mage and self-esteem. FUNDING: The National Institute for Health and Care Research (NIHR) School for Public Health Research (SPHR)
An Expansion Term In Hamilton's Equations
For any given spacetime the choice of time coordinate is undetermined. A
particular choice is the absolute time associated with a preferred vector
field. Using the absolute time Hamilton's equations are
+ (\delta H_{c})/(\delta \pi)=\dot{q}\Theta = V^{a}_{.;a}N\equiv exp(-\int\Theta d \ta)\pi^{N}\pi^N$. Briefly the possibility of a non-standard sympletic form
and the further possibility of there being a non-zero Finsler curvature
corresponding to this are looked at.Comment: 10 page
A study of 15N14N isotopic exchange over cobalt molybdenum nitrides
The 14N/15N isotopic exchange pathways over Co3Mo3N, a material of interest as an ammonia synthesis catalyst and for the development of nitrogen transfer reactions, have been investigated. Both the homomolecular and heterolytic exchange processes have been studied, and it has been shown that lattice nitrogen species are exchangeable. The exchange behavior was found to be a strong function of pretreatment with ca. 25% of lattice N atoms being exchanged after 40 min at 600 °C after N2 pretreatment at 700 °C compared to only 6% following similar Ar pretreatment. This observation, for which the potential contribution of adsorbed N species can be discounted, is significant in terms of the application of this material. In the case of the Co6Mo6N phase, regeneration to Co3Mo3N under 15N2 at 600 °C occurs concurrently with 14N15N formation. These observations demonstrate the reactivity of nitrogen in the Co–Mo–N system to be a strong function of pretreatment and worthy of further consideration
Runaway GC evolution in gerbil genomes
Recombination increases the local GC-content in genomic regions through GC-biased gene conversion (gBGC). The recent discovery of a large genomic region with extreme GC-content in the fat sand rat Psammomys obesus provides a model to study the effects of gBGC on chromosome evolution. Here, we compare the GC-content and GC-to-AT substitution patterns across protein-coding genes of four gerbil species and two murine rodents (mouse and rat). We find that the known high-GC region is present in all the gerbils, and is characterised by high substitution rates for all mutational categories (AT-to-GC, GC-to-AT and GC-conservative) both at synonymous and nonsynonymous sites. A higher AT-to-GC than GC-to-AT rate is consistent with the high GC-content. Additionally, we find more than 300 genes outside the known region with outlying values of AT-to-GC synonymous substitution rates in gerbils. Of these, over 30% are organised into at least 17 large clusters observable at the megabase-scale. The unusual GC-skewed substitution pattern suggests the evolution of genomic regions with very high recombination rates in the gerbil lineage, which can lead to a runaway increase in GC-content. Our results imply that rapid evolution of GC-content is possible in mammals, with gerbil species providing a powerful model to study the mechanisms of gBGC
Teachers' classroom feedback: still trying to get it right
This article examines feedback traditionally given by teachers in schools. Such feedback tends to focus on children's acquisition and retrieval of externally prescribed knowledge which is then assessed against mandated tests. It suggests that, from a sociocultural learning perspective, feedback directed towards such objectives may limit children's social development. In this article, I draw on observation and interview data gathered from a group of 27 9- to 10-year olds in a UK primary school. These data illustrate the children's perceived need to conform to, rather than negotiate, the teacher's feedback comments. They highlight the children's sense that the teacher's feedback relates to school learning but not to their own interests. The article also includes alternative examples of feedback which draw on children's own inquiries and which relate to the social contexts within which, and for whom, they act. It concludes by suggesting that instead of looking for the right answer to the question of what makes teachers' feedback effective in our current classrooms, a more productive question might be how a negotiation can be opened up among teachers and learners themselves, about how teachers' feedback could support children's learning most appropriately
myTunes: Digital music library users and their self-images
This investigation explored the relationships between individuals’ self-images and their interactions with their digital music collections via the commercially predominant program iTunes. Sixty-nine university students completed an internet-based Musical Self-Images Questionnaire (MSIQ) along with a series of questions concerning their iTunes collections. The majority of participants were highly engaged with music, regardless of their varied musical backgrounds. Factor analysis of the MSIQ data revealed two distinct self-image groups, which we label as ‘musical practitioner’ (linking ‘overall musician’, ‘performer’, ‘composer’, ‘teacher’, and ‘listener’) and ‘music consumer’ (linking ‘listener’, ‘fan’, and ‘technology user’). Participants used an average of seven attributes to categorize their music, and most consistently used one in particular to sort their collections. Those who rated themselves as higher level performers and fans used the playlist function (which involves compiling sequences of selected tracks) more often than those with lower self-ratings on those scales
A New Framework for Understanding Memories and Preference for Music
What can musical memories tell us about preference, and what can musical preferences tell us about memory? In this article we contrast the two perspectives using a dialogic conversation, drawing on insights brought into relief at the recent Music and Lifetime Memories conference. We use dialogue to present two different bodies of relevant background literature and theory and consider their overlaps, interactions, and contradictions in depth. We then compare our two different approaches to the same dataset – the Desert Island Discs archive – which provide complementary perspectives and insights. We interpret each other’s analyses from our own perspectives, and finally conclude with reflections on future directions for the field
Temperature and Kinematics of CIV Absorption Systems
We use Keck HIRES spectra of three intermediate redshift QSOs to study the
physical state and kinematics of the individual components of CIV selected
heavy element absorption systems. Fewer than 8 % of all CIV lines with column
densities greater than 10^{12.5} cm^{-2} have Doppler parameters b < 6 km/s. A
formal decomposition into thermal and non-thermal motion using the simultaneous
presence of SiIV gives a mean thermal Doppler parameter b_{therm}(CIV) = 7.2
km/s, corresponding to a temperature of 38,000 K although temperatures possibly
in excess of 300,000 K occur occasionally. We also find tentative evidence for
a mild increase of temperature with HI column density. Non-thermal motions
within components are typically small (< 10 km/s) for most systems, indicative
of a quiescent environment. The two-point correlation function (TPCF) of CIV
systems on scales up to 500 km/s suggests that there is more than one source of
velocity dispersion. The shape of the TPCF can be understood if the CIV systems
are caused by ensembles of objects with the kinematics of dwarf galaxies on a
small scale, while following the Hubble flow on a larger scale. Individual high
redshift CIV components may be the building blocks of future normal galaxies in
a hierarchical structure formation scenario.Comment: submitted to the ApJ Letters, March 16, 1996 (in press); (13 Latex
pages, 4 Postscript figures, and psfig.sty included
Supporting induction: relationships count
This article examines the structural changes to the induction of teachers in Scotland using the perceptions of a group of final year student teachers. This group would be the first probationer teachers to experience revised arrangements for new teacher induction in 37 years. Their preferences and concerns are highlighted, as the new procedures roll out in schools nationwide, in an attempt to stress the importance of relationships to the success of the induction scheme. The argument put forward in this article is based on the notion that personal intelligence is central to effective relationships and therefore crucially important in the context of this mentoring relationship. The views of our sample provide evidence to suggest that the quality of interactions between the mentor and the probationer teacher are paramount in providing a good induction experience. These views are substantiated by experiences in England and in induction literature elsewhere. A synthesis of this evidence is used to make recommendations for those involved in supporting induction in schools, local authorities or teacher education institutions
- …