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This study examines the interplay between individual and social–developmental factors in the development of positive functioning, substance use problems, and mental health problems. This interplay is nested within positive and negative developmental cascades that span childhood, adolescence, the transition to adulthood, and adulthood. Data are drawn from the Seattle Social Development Project, a gender-balanced, ethnically diverse community sample of 808 participants interviewed 12 times from ages 10 to 33. Path modeling showed short- and long-term cascading effects of positive social environments, family history of depression, and substance-using social environments throughout development. Positive family social environments set a template for future partner social environment interaction and had positive influences on proximal individual functioning, both in the next developmental period and long term. Family history of depression adversely affected mental health functioning throughout adulthood. Family substance use began a cascade of substance-specific social environments across development, which was the pathway through which increasing severity of substance use problems flowed. The model also indicated that adolescent, but not adult, individual functioning influenced selection into positive social environments, and significant cross-domain effects were found in which substance-using social environments affected subsequent mental health.
Considerable research has documented that exposure to traumatic events has negative effects on physical and mental health. Much less research has examined the predictors of traumatic event exposure. Increased understanding of risk factors for exposure to traumatic events could be of considerable value in targeting preventive interventions and anticipating service needs.
General population surveys in 24 countries with a combined sample of 68 894 adult respondents across six continents assessed exposure to 29 traumatic event types. Differences in prevalence were examined with cross-tabulations. Exploratory factor analysis was conducted to determine whether traumatic event types clustered into interpretable factors. Survival analysis was carried out to examine associations of sociodemographic characteristics and prior traumatic events with subsequent exposure.
Over 70% of respondents reported a traumatic event; 30.5% were exposed to four or more. Five types – witnessing death or serious injury, the unexpected death of a loved one, being mugged, being in a life-threatening automobile accident, and experiencing a life-threatening illness or injury – accounted for over half of all exposures. Exposure varied by country, sociodemographics and history of prior traumatic events. Being married was the most consistent protective factor. Exposure to interpersonal violence had the strongest associations with subsequent traumatic events.
Given the near ubiquity of exposure, limited resources may best be dedicated to those that are more likely to be further exposed such as victims of interpersonal violence. Identifying mechanisms that account for the associations of prior interpersonal violence with subsequent trauma is critical to develop interventions to prevent revictimization.
The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass star-forming clumps. Exploiting the unique broad frequency range and on-the-fly mapping capabilities of the Australia Telescope National Facility Mopra 22 m single-dish telescope1, MALT90 has obtained 3′ × 3′ maps towards ~2 000 dense molecular clumps identified in the ATLASGAL 870 μm Galactic plane survey. The clumps were selected to host the early stages of high-mass star formation and to span the complete range in their evolutionary states (from prestellar, to protostellar, and on to
regions and photodissociation regions). Because MALT90 mapped 16 lines simultaneously with excellent spatial (38 arcsec) and spectral (0.11 km s−1) resolution, the data reveal a wealth of information about the clumps’ morphologies, chemistry, and kinematics. In this paper we outline the survey strategy, observing mode, data reduction procedure, and highlight some early science results. All MALT90 raw and processed data products are available to the community. With its unprecedented large sample of clumps, MALT90 is the largest survey of its type ever conducted and an excellent resource for identifying interesting candidates for high-resolution studies with ALMA.
A survey of the Milky Way disk and the Magellanic System at the wavelengths of the 21-cm atomic hydrogen (H i) line and three 18-cm lines of the OH molecule will be carried out with the Australian Square Kilometre Array Pathfinder telescope. The survey will study the distribution of H i emission and absorption with unprecedented angular and velocity resolution, as well as molecular line thermal emission, absorption, and maser lines. The area to be covered includes the Galactic plane (|b| < 10°) at all declinations south of δ = +40°, spanning longitudes 167° through 360°to 79° at b = 0°, plus the entire area of the Magellanic Stream and Clouds, a total of 13 020 deg2. The brightness temperature sensitivity will be very good, typically σT≃ 1 K at resolution 30 arcsec and 1 km s−1. The survey has a wide spectrum of scientific goals, from studies of galaxy evolution to star formation, with particular contributions to understanding stellar wind kinematics, the thermal phases of the interstellar medium, the interaction between gas in the disk and halo, and the dynamical and thermal states of gas at various positions along the Magellanic Stream.
A heuristic greedy algorithm is developed for efficiently tiling spatially dense redshift surveys. In its first application to the Galaxy and MassAssembly (GAMA) redshift survey we find it rapidly improves the spatial uniformity of our data, and naturally corrects for any spatial bias introduced by the 2dF multi-object spectrograph. We make conservative predictions for the final state of the GAMA redshift survey after our final allocation of time, and can be confident that even if worse than typical weather affects our observations, all of our main survey requirements will be met.
Early Intervention in Psychosis Services (EIS) for young people in England experiencing first-episode psychosis (FEP) were commissioned in 2002, based on an expected incidence of 15 cases per 100 000 person-years, as reported by schizophrenia epidemiology in highly urban settings. Unconfirmed reports from EIS thereafter have suggested higher than anticipated rates. The aim of this study was to compare the observed with the expected incidence and delineate the clinical epidemiology of FEP using epidemiologically complete data from the CAMEO EIS, over a 6-year period in Cambridgeshire, for a mixed rural–urban population.
A population-based study of FEP (ICD-10, F10–39) in people aged 17–35 years referred between 2002 and 2007; the denominator was estimated from mid-year census statistics. Sociodemographic variation was explored by Poisson regression. Crude and directly standardized rates (for age, sex and ethnicity) were compared with pre-EIS rates from two major epidemiological FEP studies conducted in urban English settings.
A total of 285 cases met FEP diagnoses in CAMEO, yielding a crude incidence of 50 per 100 000 person-years [95% confidence interval (CI) 44.5–56.2]. Age- and sex-adjusted rates were raised for people from black ethnic groups compared with the white British [incidence rate ratio (IRR) 2.1, 95% CI 1.1–3.8]. Rates in our EIS were comparable with pre-EIS rates observed in more urban areas after age, sex and ethnicity standardization.
Our findings suggest that the incidence observed in EIS is far higher than originally anticipated and is comparable to rates observed in more urban settings prior to the advent of EIS. Sociodemographic variation due to ethnicity and other factors extend beyond urban populations. Our results have implications for psychosis aetiology and service planning.
We have chosen the name of GYES, one of the mythological giants with one hundred arms,
offspring of Gaia and Uranus, for our instrument study of a multifibre spectrograph for
the prime focus of the Canada-France-Hawaii Telescope. Such an instrument could provide an
excellent ground-based complement for the Gaia mission and a northern complement to the
HERMES project on the AAT. The CFHT is well known for providing a stable prime focus
environment, with a large field of view, which has hosted several imaging instruments, but
has never hosted a multifibre spectrograph. Building upon the experience gained at GÉPI
with FLAMES-Giraffe and X-Shooter, we are investigating the feasibility of a high
multiplex spectrograph (about 500 fibres) over a field of view one degree in diameter. We
are investigating an instrument with resolution in the range 15 000 to 30 000, which
should provide accurate chemical abundances for stars down to 16th magnitude and radial
velocities, accurate to 1 km s-1 for fainter stars. The study is led by
GÉPI-Observatoire de Paris with a contribution from Oxford for the study of the
positioner. The financing for the study comes from INSU CSAA and Observatoire de Paris.
The conceptual study will be delivered to CFHT for review by October 1st 2010.
We recently presented (Sbordone et al., 2009a) the largest sample to date of lithium abundances in extremely metal-poor (EMP) Halo dwarf and Turn-Off (TO) stars. One of the most crucial aspects in estimating Li abundances is the Teff determination, since the Li I 670.8 nm doublet is highly temperature sensitive. In this short contribution we concentrate on the Teff determination based on Hα wings fitting, and on its sensitivity to the chosen stellar gravity.
We present the largest sample available to date of lithium abundances in extremely metal poor (EMP) Halo dwarfs. Four Teff estimators are used, including IRFM and Hα wings fitting against 3D hydrodynamical synthetic profiles. Lithium abundances are computed by means of 1D and 3D-hydrodynamical NLTE computations. Below [Fe/H]~−3, a strong positive correlation of A(Li) with [Fe/H] appears, not influenced by the choice of the Teff estimator. A linear fit finds a slope of about 0.30 dex in A(Li) per dex in [Fe/H], significant to 2–3 σ, and consistent within 1 σ among all the Teff estimators. The scatter in A(Li) increases significantly below [Fe/H]~−3. Above, the plateau lies at 〈A(Li)3D, NLTE〉 = 2.199 ± 0.086. If the primordial A(Li) is the one derived from standard Big Bang Nucleosynthesis (BBN), it appears difficult to envision a single depletion phenomenon producing a thin, metallicity independent plateau above [Fe/H] = −2.8, and a highly scattered, metallicity dependent distribution below.
Two trials were performed to assess changes in the physicochemical properties of precisely processed (micronised v. extruded) wheats, prior to inclusion in piglet diets. The in vitro data obtained were subsequently related to biological responses of newly weaned piglets over 14 days. The effects of the severity of micronisation (Trial 1) or extrusion (Trial 2) on the nutritional value of two wheats (varying in endosperm texture) were examined. Extrusion, in contrast to micronisation, drastically disrupted the structural properties of wheat starch granules through melting of crystallites and macromolecular degradation of starch polysaccharides. These structural changes strongly improved the hydration characteristics of starch and its digestibility. The amount of starch digested in vitro was approximately 0.20, 0.70 and 0.90 for the unprocessed, micronised and extruded samples, respectively. This enhanced in vitro digestibility correlated well with, and helped to explain, the significant improvement in the apparent digestibility of starch at both the 0.5 region (mean coefficients for extruded wheat were 0.869 and 0.959 v. raw 0.392; P = 0.017) and 0.75 region (extruded 0.973 v. raw 0.809; P = 0.009) of the small intestine, when compared with piglets fed an unprocessed wheat diet. Extrusion and, to a lesser extent, micronisation lessened the reduction in apparent starch digestibility on day 4 post-weaning, typically seen at the 0.5 intestinal region in piglets fed an unprocessed wheat diet. Processing variables influenced both in vitro and in vivo data, with for instance, a positive relationship between specific mechanical energy (SME) input during extrusion and starch digestibility at the 0.5 region. The higher digestibility coefficient observed at the 0.5 region for the high SME diet suggests enhanced digestion and more rapid release of starch. However, it remains to be seen whether a diet containing rapidly digestible, as opposed to slowly digestible, starch is more beneficial for piglets. This rate of starch breakdown in the piglet is an important finding, which may have implications in helping to alleviate the post-weaning growth check, particularly in the absence of in-feed antibiotic growth promoters. Processing did not appear to offer any benefit over unprocessed wheat with regard to daily live-weight gain or the apparent digestibility of nitrogen in the small intestine over the 14-day period. Based on the enhanced in vivo starch digestibility, performance might be improved over a longer period, although future studies are required to confirm this. Precise processing variables for raw materials must be stated in all animal trials.
The digestibility of the starch component of raw cereals in newly weaned piglets is highly variable. Reasons for this must be elucidated if the most suitable cereals are to be used. A novel approach was employed, which consisted of assessing the physicochemical properties (rapid visco analysis, water absorption and solubility indices, particle size distribution and in vitro amylolytic digestion) of eight raw cereals contained within piglet diets and subsequently relating this in vitro data to the biological responses of weaned piglets. Trial 1 examined soft and hard wheat, trial 2 – soft wheat, barley, rye and triticale, and trial 3 – soft wheat, naked oats, whole oats and maize. The initial observation was that in vitro testing prior to animal trials is recommended in nutritional evaluation since it indicated fundamental differences between raw cereals, such as for example the levels of endogenous amylase in wheat. Starch and nitrogen digestibility differed between cereals (apparent digestibility coefficients at the 0.5 site of the small intestine ranged from 0.10 to 0.69 for starch and from 0.17 to 0.68 for nitrogen). There is also a probable relationship between the coefficients of ileal apparent starch digestibility, at approximately halfway from the gastric pylorus to the ileocaecal valve, and the presence of endogenous amylase (mean values of 0.53 and 0.62 in trials 2 and 3, respectively, for the higher amylase wheat; 0.38 for the low-amylase wheat used in trial 1). This additional variable (i.e. the unforeseen presence of endogenous amylase) in wheat made it more difficult to draw a firm conclusion about the nutritional suitability of the different cereals. All raw-cereal diets caused atrophy of the villi during the initial week following weaning, but the soft wheat was associated with the highest comparative villi height and might therefore be considered the best of all raw cereals in minimising the post-weaning growth check. For wheat, this might also suggest a possible interaction between villus architecture and endosperm texture in the immediate post-weaning period.
The Fornax dSph is a nearby dwarf spheroidal galaxy with five globular
clusters and a complex star formation history. It is one of the most
massive dwarf spheroidal galaxies in the Local Group. Using the
FLAMES/GIRAFFE spectrograph on the VLT, we have obtained high
resolution (R ~ 20 000) spectra for 80 Red Giant Branch stars in the
central 25' of the Fornax dSph. We present abundance ratios for some
of the elements we have in our analysis,
including alpha (Mg and Ca), iron-peak (Fe and Ni) and heavy (Y,
Ba, Eu) elements. We compare our results with the Milky Way
(MW) and our recent VLT/UVES abundance
determinations of nine individual stars in Fornax globular
Wheat is a major component of piglet diets, representing a significant source of energy. Nutritional value of wheat can be influenced by genetic and environmental factors (Wiseman and Inborr, 1990). Previous work examining the effect of wheat cultivar on pig performance has failed to show a clear relationship with digestibility (Lewis et al., 1999), although selection of which wheats to evaluate has invariably been unstructured. The aim of the current study was to investigate the effect of wheat endosperm texture, in wheats which were closely related, on nutritional value for the newly weaned piglet.
The piglet is susceptible to digestive upsets associated with the post-weaning growth check. To minimise this, heat treatment of cereals is used to cereal starch by reducing crystalinity, thereby increasing digestibility and dietary energy-yielding value (Lawrence, 1973a). However, benefits from heat treating are difficult to compare due to the number of processing variables used and, often, a failure to declare variables. Two trials were designed using controlled variables to assess the effect of heat processing (through micronisation and extrusion) on wheat nutritional value, and to determine whether responses to processing are affected by endosperm texture.
This paper examines the design of a composite helicopter rotor blade to meet given cross-sectional properties. As with many real-world problems, the choice of objective and design variables can lead to a problem with a non-linear and/or non-convex objective function, which would require the use of stochastic optimisation methods to find an optimum. Since the objective function is evaluated from the results of a finite element analysis of the cross section, the computational expense of using stochastic methods would be prohibitive. It is shown that by choosing appropriate simplified design variables, the problem becomes convex with respect to those design variables. This allows deterministic optimisation methods to be used, which is considerably more computationally efficient than stochastic methods. It is also shown that the design variables can be chosen such that the response of each individual cross-sectional property can be closely modelled by a linear approximation, even though the response of a single objective function to many design parameters is non-linear. The design problem may therefore be reformulated into a number of simultaneous linear equations that are easily solved by matrix methods, thus allowing an optimum to be located with the minimum number of computationally expensive finite element analyses.