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The present study aimed to: (i) evaluate changes in Canadian children’s dietary quality during school hours and on school days between 2004 and 2015; and (ii) explore whether changes in dietary quality over time were moderated by sociodemographic characteristics.
Nationally representative 24 h dietary recall data were obtained from the 2004 (n 4827) and 2015 (n 2447) Canadian Community Health Surveys. Dietary quality was measured using the Canadian Healthy Eating Index (C-HEI) which evaluates respondents’ compliance with 2007 national dietary recommendations, and the school-HEI which assesses respondents’ dietary quality during school hours. Multivariable regression models compared differences in dietary quality between 2004 and 2015. Interaction effects were used to test whether changes over time were moderated by sociodemographic characteristics (sex, age group, ethnicity, residential location, province of residence, parental education, food security status).
Children aged 6–17 years.
Mean school-HEI score rose from 51.3 to 58.0 points (maximum = 100) from 2004 to 2015 (P < 0.001). School-HEI sub-scores for total vegetables and fruit, whole fruit, dark green and orange vegetables, milk and alternatives, and meat and alternatives improved over time, but remained well below recommendations. Decreased energy from minimally nutritious foods accounted for 39 % of the improvement in mean school-HEI scores. Mean whole day C-HEI scores also improved (60.8 to 66.4 points, P < 0.001). There was no evidence of a moderating effect for any of the sociodemographic variables examined.
Mean dietary quality of Canadian children during school hours and on school days improved modestly for all age and sex groups but remained below 2007 national dietary recommendations.
Shiga toxin-producing Escherichia coli (STEC) infection can cause serious illness including haemolytic uraemic syndrome. The role of socio-economic status (SES) in differential clinical presentation and exposure to potential risk factors amongst STEC cases has not previously been reported in England. We conducted an observational study using a dataset of all STEC cases identified in England, 2010–2015. Odds ratios for clinical characteristics of cases and foodborne, waterborne and environmental risk factors were estimated using logistic regression, stratified by SES, adjusting for baseline demographic factors. Incidence was higher in the highest SES group compared to the lowest (RR 1.54, 95% CI 1.19–2.00). Odds of Accident and Emergency attendance (OR 1.35, 95% CI 1.10–1.75) and hospitalisation (OR 1.71, 95% CI 1.36–2.15) because of illness were higher in the most disadvantaged compared to the least, suggesting potential lower ascertainment of milder cases or delayed care-seeking behaviour in disadvantaged groups. Advantaged individuals were significantly more likely to report salad/fruit/vegetable/herb consumption (OR 1.59, 95% CI 1.16–2.17), non-UK or UK travel (OR 1.76, 95% CI 1.40–2.27; OR 1.85, 95% CI 1.35–2.56) and environmental exposures (walking in a paddock, OR 1.82, 95% CI 1.22–2.70; soil contact, OR 1.52, 95% CI 2.13–1.09) suggesting other unmeasured risks, such as person-to-person transmission, could be more important in the most disadvantaged group.
The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
Parent–child relationships have long-term effects on health, particularly later inflammation and depression. We hypothesized that these effects would be mediated by later romantic partner relationships and elevated stressors in young adulthood, helping promote chronic, low grade, inflammation as well as depressive symptoms, and driving their covariation. It has been proposed recently that youth experiencing harsher parenting may also develop a stronger association between inflammation and depressive symptoms in adulthood and altered effects of stressors on outcomes. In the current investigation, we test these ideas using an 18-year longitudinal study of N = 413 African American youth that provides assessment of the parent–child relationship (at age 10), pro-inflammatory cytokine profile and depressive symptoms (at age 28), and potential mediators in early young adulthood (assessed at ages 21 and 24). As predicted, the effect of harsher parent–child relationships (age 10) on pro-inflammatory state and increased depressive symptoms at age 28 were fully mediated through young adult stress and romantic partner relationships. In addition, beyond these mediated effects, parent–child relationships at age 10 moderated the concurrent association between inflammation and depressive symptoms, as well as the prospective association between romantic partner relationships and inflammation, and resulted in substantially different patterns of indirect effects from young adult mediators to outcomes. The results support theorizing that the association of depression and inflammation in young adulthood is conditional on earlier parenting, and suggest incorporating this perspective into models predicting long-term health outcomes.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
With the changing distribution of infectious diseases, and an increase in the burden of non-communicable diseases, low- and middle-income countries, including those in Africa, will need to expand their health care capacities to effectively respond to these epidemiological transitions. The interrelated risk factors for chronic infectious and non-communicable diseases and the need for long-term disease management, argue for combined strategies to understand their underlying causes and to design strategies for effective prevention and long-term care. Through multidisciplinary research and implementation partnerships, we advocate an integrated approach for research and healthcare for chronic diseases in Africa.
Ni-based fcc alloys are frequently used as critical structural materials in nuclear energy applications. Despite extensive studies, fundamental questions remain regarding point defect migration and solute segregation as a function of grain boundary character after irradiation. In this study, a coupled experimental and modeling approach is used to understand the response of grain boundary character in a model Ni–5Cr alloy after high temperature heavy-ion irradiation. Radiation-induced segregation and void denuded zones were experimentally examined as a function of grain boundary character, while a kinetic rate theory model with grain boundary character boundary conditions was used to theoretically model Cr depletion in the alloy system. The results highlight major variations in the radiation response between the coherent and incoherent twin grain boundaries, but show limited disparity in defect sink strength between random low- and high-angle grain boundary regimes.
Although breakfast is associated with more favourable nutrient intake profiles in children, limited data exist on the impact of breakfast on nutrient adequacy and the potential risk of excessive intakes. Accordingly, we assessed differences in nutrient intake and adequacy among breakfast non-consumers, consumers of breakfasts with ready-to-eat cereal (RTEC) and consumers of other types of breakfasts. We used cross-sectional data from 12 281 children and adolescents aged 4–18 years who took part in the nationally representative Canadian Community Health Survey, 2004. Mean nutrient intakes (obtained using a multiple-pass 24 h recall method) were compared among the breakfast groups using covariate-adjusted regression analysis. Usual nutrient intake distributions, generated using the National Cancer Institute method, were used to determine the prevalence of nutrient inadequacy or the potential risk of excessive intakes from food sources alone and from the combination of food plus supplements. Of these Canadian children, 10 % were breakfast non-consumers, 33 % were consumers of RTEC breakfasts and 57 % were consumers of other types of breakfasts. Non-consumption of breakfast increased with age (4–8 years: 2 %; 9–13 years: 9 %; 14–18 years: 18 %). Breakfast consumers had higher covariate-adjusted intakes of energy, many nutrients and fibre, and lower fat intakes. The prevalence of nutrient inadequacy for vitamin D, Ca, Fe and Mg (from food alone or from the combination of food plus supplements) was highest in breakfast non-consumers, intermediate in consumers of other types of breakfasts and lowest in consumers of RTEC breakfast. For vitamin A, P and Zn, breakfast non-consumers had a higher prevalence of nutrient inadequacy than both breakfast groups. The potential risk of excessive nutrient intakes was low in all groups. Efforts to encourage and maintain breakfast consumption in children and adolescents are warranted.
Beyond academic vocabulary, the constellation of skills that comprise academic language proficiency has remained imprecisely defined. This study proposes an expanded operationalization of this construct referred to as core academic language skills (CALS). CALS refers to the knowledge and deployment of a repertoire of language forms and functions that co-occur with school learning tasks across disciplines. Using an innovative instrument, we explored CALS in a cross-sectional sample of 235 students in Grades 4–8. The results revealed between- and within-grade variability in CALS. Psychometric analyses yielded strong reliability and supported the presence of a single CALS factor, which was found to be predictive of reading comprehension. Our findings suggest that the CALS construct and instrument appear promising for exploring students’ school-relevant language skills.
Reproductive effects from phthalate exposure have been documented mostly in animal studies. This study explored the association between prenatal exposure to phthalate metabolites, anogenital distance and penile measurements in male newborns in Toluca, State of Mexico. A total of 174 pregnant women provided urine samples for phthalate analysis during their last prenatal visit, and the 73 who gave birth to male infants were included in the study. The 73 male newborns were weighed and measured using standardized methods after delivery. After adjusting for creatinine and supine length at birth, significant inverse associations were observed between an index of prenatal exposure to total phthalate exposure and the distance from the anus to anterior base of the penis (β = −0.191 mm per 1 μg/l, P = 0.037), penile width (β = −0.0414, P = 0.050) and stretched length (β = −0.2137, P = 0.034); prenatal exposure to mono-2-ethylhexyl phthalate exposure was associated with a reduction in the stretched length of the penis (β = −0.2604, P = 0.050). Human exposure to phthalates is a public health concern, and the system most vulnerable to its potential effects seems to be the immature male reproductive tract.
In humans, it has been demonstrated that the serotonin transporter linked polymorphic region (5-HTTLPR) genotype moderates risk in the face of adversity. One mechanism by which stress could interact with genotype is via epigenetic modifications. We wanted to examine whether stress interacted with genotype to predict binding of a histone 3 protein trimethylated at lysine 3 (H3K4me3) that marks active promoters. The brains (N = 61) of male rhesus macaques that had been reared in the presence or absence of stress were archived and the hippocampusi dissected. Chromatin immunoprecipitation was performed with an antibody against H3K4me3 followed by sequencing on a SolexaG2A. The effects of age, genotype (5-HTTLPR long/long vs. short), and stress exposure (peer-reared vs. mother-reared) on levels of H3K4me3 binding were determined. We found effects of age and stress exposure. There was a decline in H3K4me3 from preadolescence to postadolescence and lower levels in peer-reared monkeys and no effects of genotype. When we controlled for age, however, we found that there were effects of 5-HTTLPR genotype and rearing condition on H3K4me3 binding. In a larger sample, we observed that cerebrospinal fluid 5-hydroxyindoleacetic acid levels were subject to interactive effects among age, rearing history, and genotype. Genes containing both genetic selection and epigenetic regulation may be particularly important in stress adaptation and development. We find evidence for selection at the solute carrier family C6 member 4 gene and observe epigenetic reorganization according to genotype, stress, and age. These data suggest that developmental stage may moderate effects of stress and serotonin transporter genotype in the emergence of alternative adaptation strategies and in the vulnerability to developmental or psychiatric disorders.
The short allele of the serotonin transporter linked polymorphic region (5-HTTLPR) moderates the effects of stress on vulnerability to mood and anxiety disorders. The mechanism by which this occurs may relate to differential sensitivity to stressful life events. Here we explored whether 5-HTTLPR and sex affected behavioral responses to repeated maternal separation in infant rhesus macaques. Behaviors were collected during the acute (Day 1) and the chronic (Days 2–4) phases of the separation, and the effects of duration of separation (acute vs. chronic), genotype (long/long vs. short allele), and sex (male vs. female) on behavioral responses were analyzed across four successive separations. Males increased their levels of locomotion with repeated maternal separation, whereas females exhibited an increase in frequency of self-directed behavior, a measure of “depression-like” behavior. The short-allele predicted increased environmental exploration, particularly during the chronic phase of social separation, indicative of higher arousal. In addition, the short-allele carriers were more likely to increase their levels of self-directed behavior during the chronic phase of separation, as a function of repeated exposures. These findings suggest that the short allele may increase reactivity to repeated, chronic stressors, leaving them more vulnerable to affective psychopathology, with females particularly vulnerable.
Humans have dramatically altered biotic communities around the world. During the process of converting forests, grasslands, and wetlands for agriculture, urban development, and transportation, the remnants of natural habitat have become increasingly fragmented. This fragmentation of habitat has many biological consequences. Foremost is the reduction of available habitat resulting in a reduced size of populations of species dependent on natural land covers (Andren 1994; Fahrig 1997, 2003). Fragmentation, though, is more than just habitat loss; it is also the division of remaining habitat into patches that experience at least partial isolation from other such fragments (Fahrig 2003). Fragmentation increases habitat edges and, consequently, the exposure of populations to the resulting alterations in microclimate and biota associated with edge environments (Suarez et al. 1998; Fagan et al. 1999). As fragments become more isolated, the frequency of movements between fragments is reduced. Furthermore, when localized extinctions in isolated fragments occur, immigration from neighboring fragments can be insufficient to allow recolonization (Tilman et al. 1994; Fahrig 2003). Extinctions associated with demographic stochasticity are expected to be more common in small fragments than in more continuous habitat tracts (Griffen & Drake 2008).
The consequences of fragmentation have the potential to influence genetic diversity in species requiring continuous tracts of habitat (see Chapter 8 by J. Hamrick). Localized population declines cause allele frequencies to drift; moreover, widespread population declines due to fragmentation across the range of a species may reduce its effective population size (Pannell & Charlesworth 2000; Alo & Turner 2005). With declines of census and effective population size, inhabitants of isolated fragments begin to resemble independent populations, become more vulnerable to stochastic processes, lose genetic diversity, and increase in relatedness (Barrowclough 1980; Leberg 2005).
Substance misuse is a common comorbid problem in people presenting with
first-episode psychosis and is associated with a poor short-term
The aim of this study is to examine differences in baseline
characteristics and 1-year outcome between individuals with first-episode
psychosis who have never misused substances, those who stop misusing
substances after initial presentation and those who persistently misuse
substances over the 1-year assessment period.
Patients were recruited to the Northern Ireland First Episode Psychosis
Study (n = 272). Clinical assessments were performed at baseline and at 1
year (n = 194) and data were collected from the case notes.
Individuals with persistent substance misuse had more severe depression,
more positive symptoms, poorer functional outcome and greater rates of
relapse at 1 year than those who stopped and those who had never misused
substances. There were no differences in outcome between people who had
never misused substances and those who stopped misusing after
These results support assertive intervention targeted at comorbid
substance misuse in individuals with first-episode psychosis.
An investigation was undertaken in relation to the contamination of a facility used for the servicing and refurbishment of gaseous tritium light devices. While it is generally accepted that there is minimal exposure hazard from a broken gaseous tritium light source after the tritium gas has dispersed, environmental tritium contamination displaying 'particulate' like characteristics was observed during the radiological assessment of the facility in 2003. The contamination is considered to be associated with zinc sulphide phosphor residues from damaged tritium light sources. A subsequent environmental tritium survey was conducted in 2007, in the vicinity of the affected building to determine the extent of contamination and impact on current and future occupancy and land use application. The survey was conducted by measuring both soil non-aqueous tritium and soil pore water tritium concentration. Zinc concentration, from the zinc sulphide phosphor, was also measured for the same samples to assess correlation between tritium contamination activity and the identified source material. Greater than 97% of the soil non-aqueous tritium results were observed to be less than the derived tritium residential screening level of 8.5 Bq ⋅ kg-1, and that soil pore water tritium concentrations had decreased from 8 MBq ⋅ L-1 to less than 2 kBq ⋅ L-1 over a period of 5 years. Elevated elemental zinc levels in the upper surface soils correlated with increased non-aqueous tritium concentration. Ground water tritium concentrations ranged from 3 Bq ⋅ L-1 to 20 Bq ⋅ L-1, indicating leakage of tritium contaminated water to local aquifer systems. Natural attenuation and dilution processes have reduced environmental tritium contamination levels over a period of 5 years since the introduction of new contamination control policies and operational changes at the facility.
Photogrammetric processing of archival stereo imagery offers the opportunity to reconstruct glacier volume changes for regions where no such data exist, and to better constrain the contribution to sea-level rise from small glaciers and ice caps. The ability to derive digital elevation model (DEM) measurements of glacier volume from photogrammetry relies on good-quality, well-distributed ground reference data, which may be difficult to acquire. This study shows that ground-control points (GCPs) can be identified and extracted from point-cloud airborne lidar data and used to control photogrammetric glacier models. The technique is applied to midtre Lovénbreen, a small valley glacier in northwest Svalbard. We show that the amount of ground control measured and the elevation accuracy of GCP coordinates (based on known and theoretical error considerations) has a significant effect on photogrammetric model statistics, DEM accuracy and the subsequent geodetic measurement of glacier volume change. Models controlled with fewer than 20 lidar control points or GCPs from sub-optimal areas within the swath footprint overestimated volume change by 14–53% over a 2 year period. DEMs derived from models utilizing 20–25 or more GCPs, however, gave volume change estimates within ∼4% of those from repeat lidar data (−0.51 m a−1 between 2003 and 2005). Our results have important implications for the measurement of glacier volume change from archival stereo-imagery sources.