Are teachers' judgements of pupils' ability influenced by body shape?

BACKGROUND: Evidence indicates that teachers can judge pupils on the basis of their physical appearance, including their body shape. Teacher bias towards obese pupils has been suggested as a potential pathway through which obese children attain relatively lower academic levels. The aim of this study was to investigate whether teachers' judgements of pupils' ability are influenced by the body shape of the child. METHODS: The sample includes English, singleton children in state schools from the Millennium Cohort Study. The data were taken from the fourth wave of data collection, when the children were approximately 7 years old. In all, 5086/5072 children had teacher ability ratings of reading and maths. Logistic regression analyses were used to test whether teachers' perceptions of the child's reading and mathematics ability were influenced by the pupil's waist circumference, conditional upon cognitive test scores of reading and maths ability. RESULTS: After adjustment for cognitive test scores, no significant overall relationship was found between the pupil's waist circumference and the teacher's judgements of ability. No statistically significant differences were observed in the probability of being judged as above average after further adjustments were made for potential confounders. CONCLUSIONS: There is little evidence that teachers' judgements of pupils' ability are influenced by obesity.

The brunhes epoch: isotopic paleotemperatures and geochronology.

Oxygent isotopic analysis of a long piston core from the western equatorial Pacific has produced a record for the entire Brunhes epoch. This record can be correlated point by point with the isotopic records of previously analyzed Atlantic and Caribbean cores, leading to the construction of a generalized temperature curve for the entire Brunhes epoch.

Variations in the Earth's Orbit: Pacemaker of the Ice Ages.

1) Three indices of global climate have been monitored in the record of the past 450,000 years in Southern Hemisphere ocean-floor sediments. 2) Over the frequency range 10(-4) to 10(-5) cycle per year, climatic variance of these records is concentrated in three discrete spectral peaks at periods of 23,000, 42,000, and approximately 100,000 years. These peaks correspond to the dominant periods of the earth's solar orbit, and contain respectively about 10, 25, and 50 percent of the climatic variance. 3) The 42,000-year climatic component has the same period as variations in the obliquity of the earth's axis and retains a constant phase relationship with it. 4) The 23,000-year portion of the variance displays the same periods (about 23,000 and 19,000 years) as the quasi-periodic precession index. 5) The dominant, 100,000-year climatic [See table in the PDF file] component has an average period close to, and is in phase with, orbital eccentricity. Unlike the correlations between climate and the higher-frequency orbital variations (which can be explained on the assumption that the climate system responds linearly to orbital forcing), an explanation of the correlation between climate and eccentricity probably requires an assumption of nonlinearity. 6) It is concluded that changes in the earth's orbital geometry are the fundamental cause of the succession of Quaternary ice ages. 7) A model of future climate based on the observed orbital-climate relationships, but ignoring anthropogenic effects, predicts that the long-term trend over the next sevem thousand years is toward extensive Northern Hemisphere glaciation.

Laurentide ice sheet meltwater recorded in gulf of Mexico deep-sea cores.

Oxygen isotopic measurements in three Late Quaternary deep-sea cores from the Gulf of Mexico record a major anomaly between about 15,000 and 12,000 years ago superimposed on a more characteristic oceanic oxygen isotopic curve. This resulted from major influx of isotopically light glacial meltwater via the Mississippi River from the disintegrating Late Wisconsin Laurentide Ice Sheet 2000 kilometers to the north.

Direct marine-continental correlation: 150,000-year oxygen isotope--pollen record from the north pacific.

Core Y72 II I (43 degrees 15'N, 126 degrees 22'W) contains sediment of oxygen isotope stages I through 6 (substages 5a through 5e are well developed) and abundant pollen from the nearby continent, enabling us for the first time to obtain a direct marine-continental correlation of events in the last interglacial sensu lato. From stage 6 to substage 5e the vegetational record resembles that during the waning of the last glacial. During substage 5e, after a rapid increase of alder, western hemlock was abundant and significant amounts of redwood, oak, and Douglas fir appeared. These results suggest that vegetation on the adjacent continent during substage 5e was similar to that of the temperate conifer forests which developed in the Pacific Northwest during the Holocene. The vegetation record since that brief episode (which like the Eemian in northwest Europe lasted only afew thousand years) has been complex.

Paleocirculation of the deep north atlantic: 150,000-year record of benthic foraminifera and oxygen-18.

Benthic foraminiferal faunas in a piston core from 3331 meters at 44 degrees N on the Mid-Atlantic Ridge show striking variations in the relative abundance of species. Uvigerina peregrina, which is broadly distributed today in the South Atlantic and in the Pacific in water that has been long isolated from the surface, is absent in the North and Equatorial Atlantic at depths occupied by highly oxygenated North Atlantic deep water. This species dominated the fauna at this site for much of the past 150,000 years. It is suggested that North Atlantic deepwater production was much reduced or eliminated at times of Uvigerina peregrina abundance, as a result of cooling and stratification of the Norwegian Sea surface, coincident with the times of the southward migration of the polar front in the North Atlantic.

Climate response to orbital forcing across the Oligocene-Miocene boundary.

Spectral analyses of an uninterrupted 5.5-million-year (My)-long chronology of late Oligocene-early Miocene climate and ocean carbon chemistry from two deep-sea cores recovered in the western equatorial Atlantic reveal variance concentrated at all Milankovitch frequencies. Exceptional spectral power in climate is recorded at the 406-thousand-year (ky) period eccentricity band over a 3.4-million-year period [20 to 23.4 My ago (Ma)] as well as in the 125- and 95-ky bands over a 1.3-million-year period (21.7 to 23.0 Ma) of suspected low greenhouse gas levels. Moreover, a major transient glaciation at the epoch boundary ( approximately 23 Ma), Mi-1, corresponds with a rare orbital congruence involving obliquity and eccentricity. The anomaly, which consists of low-amplitude variance in obliquity (a node) and a minimum in eccentricity, results in an extended period ( approximately 200 ky) of low seasonality orbits favorable to ice-sheet expansion on Antarctica.

Improving rates of overweight, obesity and extreme obesity in New Zealand 4-year-old children in 2010-2016.

BACKGROUND: Prevalence of childhood obesity is high in developed countries, and there is a growing concern regarding increasing socio-economic disparities. OBJECTIVES: To assess trends in the prevalence of overweight, obesity and extreme obesity among New Zealand 4-year olds, and whether these differ by socio-economic and ethnic groupings. METHODS: A national screening programme, the B4 School Check, collected height and weight data for 75-92% of New Zealand 4-year-old children (n = 317 298) between July 2010 and June 2016. Children at, or above, the 85th, 95th and 99.7th percentile for age and sex adjusted body mass index (according to World Health Organization standards) were classified as overweight, obese and extremely obese, respectively. Prevalence rates across 6 years (2010/11 to 2015/16) were examined by sex, across quintiles of socio-economic deprivation, and by ethnicity. RESULTS: The prevalence of overweight, obesity and extreme obesity decreased by 2.2 [95% CI, 1.8-2.5], 2.0 [1.8-2.2] and 0.6 [0.4-0.6] percentage points, respectively, between 2010/2011 and 2015/2016. The downward trends in overweight, obesity and extreme obesity in the population persisted after adjustment for sex, ethnicity, deprivation and urban/rural residence. Downward trends were also observed across sex, ethnicity and deprivation groups. CONCLUSIONS: The prevalence of obesity appears to be declining in 4-year-old children in New Zealand across all socio-economic and ethnic groups.

Intraclass correlation values for adolescent health outcomes in secondary schools in 21 European countries.

BACKGROUND: Cluster randomised controlled trials (CRCTs) are increasingly used to evaluate the effectiveness of interventions for improving health. A key feature of CRCTs is that individuals in clusters are often more alike than individuals in different clusters, irrespective of treatment. This similarity within clusters needs to be taken into account when planning CRCTs to obtain adequate sample sizes, and when analysing clustered data to obtain correct estimates. METHODS: Nationally representative data from 15 to 16 year olds were analysed, from 21 of the 35 countries that participated in the 2007 European School Survey Project on Alcohol and Other Drugs. Within country school level intra-class correlation coefficients (ICCs) were calculated for substance use (self-reported alcohol use, regular alcohol use, binge drinking, any smoking, regular smoking, and illicit drug use) and psychosocial health (depressive mood and self-esteem). Unadjusted and adjusted ICCs are presented. ICCs are adjusted for student sex and socioeconomic status. RESULTS: ICCs ranged from 0.01 to 0.21, with the highest (0.21) reported for regular smoking. Within country school level ICCs varied substantially across health outcomes, and among countries for the same health outcomes. Estimated ICCs were consistently higher for substance use (range 0.01-0.21), than for psychosocial health (range 0.01-0.07). Within country ICCs for health outcomes varied by changes in the measurement of particular health outcomes, for example the ICCs for regular smoking (range 0.06-0.21) were higher than those for having smoked at all in the last month (range 0.03-0.17). CONCLUSIONS: For school level ICCs to be effectively utilised in informing sample size requirements for CRCTs and adjusting estimates from meta-analyses, the school level ICCs need to be both country and outcome specific.

Prediction of child abuse in an ambulatory setting.

A prospective random study was performed on 476 patients, up to 2 years of age, by full-time registered nurses in the emergency room. The parent (caretaker) and child were assessed in an effort to predict child abuse. The incidence of abuse rose from 2.5% to 15.2% if one or more abnormal features were present in parent or child (p less than .0003). Abuse developed in 19% of unkempt children and 28% of children with abnormal bruises, burns, or bites. The incidence of abuse increased to 42% (P less than .002) when these factors were present together. An unkempt child with an abnormal parenting pattern and a 30% chance of being abused (P = .007).

Neolithic trade routes re-aligned by oxygen isotope analyses.

Oxygen isotope analyses of Spondylus shells from neolithic sites suggest that the source for the shells used as ornaments in the Balkans and central Europe during the fourth millennium BC was the Aegean and not the Black Sea. The trade in Spondylus may have taken the form of an exchange of gifts.

The duration of forest stages in southern Europe and interglacial climate variability.

Foraminiferal oxygen isotope and pollen analyses from a deep-sea sequence off southwest Portugal show that the duration of temperate stages on land over the past 350,000 years varied considerably. The record shows forest contractions during intervals of low ice volume, coeval with declines in atmospheric methane, after which tree populations did not always recover. What emerges is that, although the broad timing of interglacials is consistent with orbital theory, their specific duration may be dictated by millennial variability. This complicates the prediction of the natural duration of interglacials, at least until the origin of this climate variability is understood.

Intensified deep Pacific inflow and ventilation in Pleistocene glacial times.

The production of cold, deep waters in the Southern Ocean is an important factor in the Earth's heat budget. The supply of deep water to the Pacific Ocean is presently dominated by a single source, the deep western boundary current east of New Zealand. Here we use sediment records deposited under the influence of this deep western boundary current to reconstruct deep-water properties and speed changes during the Pleistocene epoch. In physical and isotope proxies we find evidence for intensified deep Pacific Ocean inflow and ventilation during the glacial periods of the past 1.2 million years. The changes in throughflow may be directly related to an increased production of Antarctic Bottom Water during glacial times. Possible causes for such an increased bottom-water production include increasing wind strengths in the Southern Ocean or an increase in annual sea-ice formation, leaving dense water after brine rejection and thereby enhancing deep convection. We infer also that the global thermohaline circulation was perturbed significantly during the mid-Pleistocene climate transition between 0.86 and 0.45 million years ago.

Warm tropical sea surface temperatures in the Late Cretaceous and Eocene epochs.

Climate models with increased levels of carbon dioxide predict that global warming causes heating in the tropics, but investigations of ancient climates based on palaeodata have generally indicated cool tropical temperatures during supposed greenhouse episodes. For example, in the Late Cretaceous and Eocene epochs there is abundant geological evidence for warm, mostly ice-free poles, but tropical sea surface temperatures are generally estimated to be only 15-23 degrees C, based on oxygen isotope palaeothermometry of surface-dwelling planktonic foraminifer shells. Here we question the validity of most such data on the grounds of poor preservation and diagenetic alteration. We present new data from exceptionally well preserved foraminifer shells extracted from impermeable clay-rich sediments, which indicate that for the intervals studied, tropical sea surface temperatures were at least 28-32 degrees C. These warm temperatures are more in line with our understanding of the geographical distributions of temperature-sensitive fossil organisms and the results of climate models with increased CO2 levels.