Increased awareness of the importance of vitamin D to health has led to concerns about the prevalence of hypovitaminosis D in many parts of the world.
We aimed to determine the prevalence of ...hypovitaminosis D in the white British population and to evaluate the influence of key dietary and lifestyle risk factors.
We measured 25-hydroxyvitamin D 25(OH)D in 7437 whites from the 1958 British birth cohort when they were 45 y old.
The prevalence of hypovitaminosis D was highest during the winter and spring, when 25(OH)D concentrations <25, <40, and <75 nmol/L were found in 15.5%, 46.6%, and 87.1% of participants, respectively; the proportions were 3.2%, 15.4%, and 60.9%, respectively, during the summer and fall. Men had higher 25(OH)D concentrations, on average, than did women during the summer and fall but not during the winter and spring (P = 0.006, likelihood ratio test for interaction). 25(OH)D concentrations were significantly higher in participants who used vitamin D supplements or oily fish than in those who did not (P < 0.0001 for both) but were not significantly higher in participants who consumed vitamin D-fortified margarine than in those who did not (P = 0.10). 25(OH)D concentrations <40 nmol/L were twice as likely in the obese as in the nonobese and in Scottish participants as in those from other parts of Great Britain (ie, England and Wales) (P < 0.0001 for both).
Prevalence of hypovitaminosis D in the general population was alarmingly high during the winter and spring, which warrants action at a population level rather than at a risk group level.
We present a new, open source, free, semi-analytic model (SAM) of galaxy formation, SHARK, designed to be highly flexible and modular, allowing easy exploration of different physical processes and ...ways of modelling them. We introduce the philosophy behind SHARK and provide an overview of the physical processes included in the model. SHARK is written in C++11 and has been parallelized with OpenMP. In the released version (V1.1), we implement several different models for gas cooling, active galactic nuclei, stellar and photo-ionization feedback, and star formation (SF). We demonstrate the basic performance of SHARK using the Planck Collaboration et al. (2016) cosmology SURFS simulations, by comparing against a large set of observations, including: the stellar mass function (SMF) and stellar-halo mass relation at z = 0-4; the cosmic evolution of the star formation rate density (SFRD), stellar mass, atomic and molecular hydrogen; local gas scaling relations; and structural galaxy properties, finding excellent agreement. Significant improvements over previous SAMs are seen in the mass-size relation for discs/bulges, the gas-stellar mass and stellar mass-metallicity relations. To illustrate the power of SHARK in exploring the systematic effects of the galaxy formation modelling, we quantify how the scatter of the SF main sequence and the gas scaling relations changes with the adopted SF law, and the effect of the starbursts H2 depletion time-scale on the SFRD and Ω _H_2. We compare SHARK with other SAMs and the hydrodynamical simulation EAGLE, and find that SAMs have a much higher halo baryon fractions due to large amounts of intra-halo gas, which in the case of EAGLE is in the intergalactic medium.
Life-long adverse effects of childhood maltreatment on mental health are well established, but effects on child-to-adulthood cognition and related educational attainment have yet to be examined in ...the general population. We aimed to establish whether different forms of child maltreatment are associated with poorer cognition and educational qualifications in childhood/adolescence and whether associations persist to midlife, parallel to associations for mental health.
Cognitive abilities at ages 7, 11, and 16 years (math, reading, and general intellectual ability) and 50 years (immediate/delayed memory, verbal fluency, processing speed) were assessed using standardized tests, and qualifications by age 42 were self-reported. Information on childhood maltreatment (neglect and abuse: sexual, physical, psychological, witnessed), cognition, and mental health was available for 8,928 participants in the 1958 British Birth Cohort.
We found a strong association of child neglect with cognitive deficits from childhood to adulthood. To illustrate, the most neglected 6% of the population (score ≥4) had a 0.60 (95% CI = 0.56-0.68) SD lower cognitive score at age 16 and a 0.28 (95% CI = 0.20-0.36) SD deficit at age 50 years relative to the non-neglected participants (score = 0) after adjustment for confounding factors and mental health, and they also had increased risk of poor qualifications (i.e., none/low versus degree-level). Childhood neglect and all forms of abuse were associated with poorer child-to-adulthood mental health, but abuse was mostly unrelated to cognitive abilities.
The study provides novel data that child neglect is associated with cognitive deficits in childhood/adolescence and decades later in adulthood, independent of mental health, and highlights the lifelong burden of child neglect on cognitive abilities and mental health.
Maturation of long-running birth cohort studies has fostered a life course approach to adult health, function, and disease and related to conceptual frameworks. Using broad concepts of human ...development including physical, cognitive, and emotional function, birth cohorts provide insights into the processes across the life course and between generations that link to adult outcomes. We discuss findings on the determinants and health consequences of lifetime trajectories of body size, cognitive and emotional function, and socioeconomic position. Findings from the studies suggest that, for some adult health outcomes, explanations will be incomplete unless exposures and processes from across the life course are taken into account. New birth cohort studies are poised to delineate further the nature and timing of life course relationships in contemporary generations of children.
OBJECTIVE: Long-term implications of childhood obesity and BMI change over the life course for risk of type 2 diabetes remain uncertain. The objective was to establish whether there are effects on ...adult glucose metabolism of 1) sensitive periods of BMI gain or 2) long duration of overweight and obesity. RESEARCH DESIGN AND METHODS: Participants in the 1958 British birth cohort with child to adult BMI and glycosylated hemoglobin (HbA1c) at 45 years (n = 7,855). RESULTS: Prevalence of type 2 diabetes or HbA1c ≥7 was 2%. BMI gains in child- and adulthood were associated with higher HbA1c: for every SD of 5-year BMI increase from 0 to 7 years, there was a 75% (95% CI 1.42–2.16) increased risk of HbA1c ≥7, increasing to a 4.7-fold (3.12–7.00) risk for the interval 23–33 years. Associations for BMI gain in adulthood were related to attained BMI but were independent for the longer period birth (or 7 years) to 45 years. Duration of obesity was also associated with HbA1c; compared with the never obese, those with childhood onset had a 23.9-fold risk (13.5–42.1) of HbA1c ≥7%; odds ratios were 16.0 (10.6–24.2) and 2.99 (1.77–5.03), respectively, for young and midadulthood onset. Similar trends by onset age were found in mean HbA1c levels and for onset of overweight. Those with the earliest age of onset had higher BMI and waist circumference at 45 years, which markedly explained the associations for onset age and HbA1c. CONCLUSIONS: Excessive BMI gain across the life span and earlier onset of overweight/obesity are associated with impaired glucose metabolism, in part through attained adult BMI.
Risk behaviours, such as smoking and physical inactivity account for up to two-thirds of all cardiovascular deaths, and are associated with substantial increased mortality in many conditions ...including cancer and diabetes. As risk behaviours are thought to co-occur in individuals we conducted a systematic review of studies addressing clustering or co-occurrence of risk behaviours and their predictors. As the main aim of the review was to inform public health policy in England we limited inclusion to studies conducted in the UK.
Key databases were searched from 1990 to 2016. We included UK based cross-sectional and longitudinal studies that investigated risk behaviours such as smoking, physical inactivity, unhealthy diet. High heterogeneity precluded meta-analyses.
Thirty-seven studies were included in the review (32 cross-sectional and five longitudinal). Most studies investigated unhealthy diet, physical inactivity, alcohol misuse, and smoking. In general adult populations, there was relatively strong evidence of clustering between alcohol misuse and smoking; and unhealthy diet and smoking. For young adults, there was evidence of clustering between sexual risk behaviour and smoking, sexual risk behaviour and illicit drug use, and sexual risk behaviour and alcohol misuse. The strongest associations with co-occurrence and clustering of multiple risk behaviours were occupation (up to 4-fold increased odds in lower SES groups) and education (up to 5-fold increased odds in those with no qualifications).
Among general adult populations, alcohol misuse and smoking was the most commonly identified risk behaviour cluster. Among young adults, there was consistent evidence of clustering found between sexual risk behaviour and substance misuse. Socio-economic status was the strongest predictor of engaging in multiple risk behaviours. This suggests the potential for interventions targeting multiple risk behaviours either sequentially or concurrently particularly where there is evidence of clustering. In addition, there is potential for intervening at the social or environmental level due to the strong association with socio-economic status.
Purpose Prospective evidence about whether the association of childhood adversity and psychopathology attenuates across the lifecourse and whether effects on mid-life psychopathology are mediated ...through adolescent and early adulthood psychopathology is limited. Methods Data were from the 1958 British Birth Cohort, a 45-year study of 98% of births in 1 week in 1958 in England, Scotland, and Wales. Outcomes included International Statistical Classification of Diseases (ICD-10) diagnoses for affective and anxiety disorders at 45 years and psychopathology at 16 years and 23 years. Multiple multi-informant measures of childhood adversity were available at 7, 11, and 16 years, with additional retrospective measures of parental sexual and physical abuse at 45 years. Analyses were determined on the basis of N = 9377; 59% of the surviving sample. Results After adjustment for socioeconomic covariates, childhood adversities were associated with adolescent, early adulthood, and mid-life psychopathology: most associations did not attenuate with age. Mid-life associations were significantly fully or partially mediated by early adulthood psychopathology: cumulative adversity, illness, sexual abuse, and physical abuse remained significantly associated with mid-life psychopathology. Conclusions The findings confirm the importance of preventing exposure to adversity and suggest that effects of adversity on mid-life psychopathology may operate through psychopathology in early adulthood. Future research is needed to examine other intermediary factors which may explain these associations.
ABSTRACT
We use the eagle simulations to study the connection between the quenching time-scale, τQ, and the physical mechanisms that transform star-forming galaxies into passive galaxies. By ...quantifying τQ in two complementary ways – as the time over which (i) galaxies traverse the green valley on the colour–mass diagram, or (ii) leave the main sequence of star formation and subsequently arrive on the passive cloud in specific star formation rate (SSFR)-mass space – we find that the τQ distribution of high-mass centrals, low-mass centrals, and satellites are divergent. In the low stellar mass regime where M⋆ < 109.6 M⊙, centrals exhibit systematically longer quenching time-scales than satellites (≈4 Gyr compared to ≈2 Gyr). Satellites with low stellar mass relative to their halo mass cause this disparity, with ram pressure stripping quenching these galaxies rapidly. Low-mass centrals are quenched as a result of stellar feedback, associated with long τQ ≳ 3 Gyr. At intermediate stellar masses where $10^{9.7}\lt M_{\star }\lt 10^{10.3}\, \rm M_{\odot }$, τQ are the longest for both centrals and satellites, particularly for galaxies with higher gas fractions. At $M_{\star }\gtrsim 10^{10.3}\, \rm M_{\odot }$, galaxy merger counts and black hole activity increase steeply for all galaxies. Quenching time-scales for centrals and satellites decrease with stellar mass in this regime to τQ ≲ 2 Gyr. In anticipation of new intermediate redshift observational galaxy surveys, we analyse the passive and star-forming fractions of galaxies across redshift, and find that the τQ peak at intermediate stellar masses is responsible for a peak (inflection point) in the fraction of green valley central (satellite) galaxies at z ≈ 0.5–0.7.
ABSTRACT
We combine the shark semi-analytic model of galaxy formation with the prospect software tool for spectral energy distribution (SED) generation to study the multiwavelength emission of ...galaxies from the far-ultraviolet (FUV) to the far-infrared (FIR) at 0 ≤ z ≤ 10. We produce a physical model for the attenuation of galaxies across cosmic time by combining a local Universe empirical relation to compute the dust mass of galaxies from their gas metallicity and mass, attenuation curves derived from radiative transfer calculations of galaxies in the eagle hydrodynamic simulation suite, and the properties of shark galaxies. We are able to produce a wide range of galaxies, from the z = 8 star-forming galaxies with almost no extinction, z = 2 submillimetre galaxies, down to the normal star-forming and red-sequence galaxies at z = 0. Quantitatively, we find that shark reproduces the observed (i) z = 0 FUV-to-FIR, (ii) 0 ≤ z ≤ 3 rest-frame K-band, and (iii) 0 ≤ z ≤ 10 rest-frame FUV luminosity functions, (iv) z ≤ 8 UV slopes, (v) the FUV-to-FIR number counts (including the widely disputed 850 μm), (vi) redshift distribution of bright $850\, \mu$m galaxies, and (vii) the integrated cosmic SED from z = 0 to 1 to an unprecedented level. This is achieved without the need to invoke changes in the stellar initial mass function, dust-to-metal mass ratio, or metal enrichment time-scales. Our model predicts star formation in galaxy discs to dominate in the FUV-to-optical, while bulges dominate at the NIR at all redshifts. The FIR sees a strong evolution in which discs dominate at z ≤ 1 and starbursts (triggered by both galaxy mergers and disc instabilities, in an even mix) dominate at higher redshifts, even out to z = 10.
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