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Risk of suicide-related behaviors is elevated among military personnel transitioning to civilian life. An earlier report showed that high-risk U.S. Army soldiers could be identified shortly before this transition with a machine learning model that included predictors from administrative systems, self-report surveys, and geospatial data. Based on this result, a Veterans Affairs and Army initiative was launched to evaluate a suicide-prevention intervention for high-risk transitioning soldiers. To make targeting practical, though, a streamlined model and risk calculator were needed that used only a short series of self-report survey questions.
We revised the original model in a sample of n = 8335 observations from the Study to Assess Risk and Resilience in Servicemembers-Longitudinal Study (STARRS-LS) who participated in one of three Army STARRS 2011–2014 baseline surveys while in service and in one or more subsequent panel surveys (LS1: 2016–2018, LS2: 2018–2019) after leaving service. We trained ensemble machine learning models with constrained numbers of item-level survey predictors in a 70% training sample. The outcome was self-reported post-transition suicide attempts (SA). The models were validated in the 30% test sample.
Twelve-month post-transition SA prevalence was 1.0% (s.e. = 0.1). The best constrained model, with only 17 predictors, had a test sample ROC-AUC of 0.85 (s.e. = 0.03). The 10–30% of respondents with the highest predicted risk included 44.9–92.5% of 12-month SAs.
An accurate SA risk calculator based on a short self-report survey can target transitioning soldiers shortly before leaving service for intervention to prevent post-transition SA.
One of Tom Dishion's most significant contributions to prevention science was the development of affordable, ecologically valid interventions, such as the Family Check-Up, that screen for child and family risk factors broadly, but concentrate family-specific interventions on those with greatest potential for population impact. In the spirit of this approach, investigators examined effects of a brief, universal postnatal home visiting program on child emergency medical care and billing costs from birth to age 24 months. Family Connects is a community-wide public health intervention that combines identification and alignment of community services and resources with brief, postpartum nurse home visits designed to assess risk, provide supportive guidance, and connect families with identified risk to community resources. Over 18 months, families of all 4,777 resident Durham County, North Carolina, births were randomly assigned based on even or odd birth date to receive a postnatal nurse home visiting intervention or services as usual (control). Independently, 549 of these families were randomly selected and participated in an impact evaluation study. Families, blind to study goals, provided written consent to access hospital administrative records. Results indicate that children randomly assigned to Family Connects had significantly less total emergency medical care (by 37%) through age 24 months, with results observed across almost all subgroups. Examination of billing records indicate a $3.17 decrease in total billing costs for each $1 in program costs. Overall, results suggest that community-wide postpartum support program can significantly reduce population rates of child emergency medical care through age 24 months while being cost-beneficial to communities.
There is limited research that explores the association between exclusion from school and mental health, but it seems intuitively plausible that the recognition of mental difficulties by key teachers and parents would influence the likelihood of exclusion from school.
A secondary analysis of the British Child and Adolescent Mental Health survey 2004, (n = 7997) and the 2007 follow-up (n = 5326) was conducted. Recognition of difficulty was assessed via a derived variable that combined the first item of the Impact supplement of the Strengths and Difficulties Questionnaire which asked parents and teachers if they thought that the child has difficulties with emotions, behaviour and concentration, and the presence/absence of psychiatric disorder measured by the Development and Well-being Assessment.
Adjusted logistic regression models demonstrated that children with recognised difficulties were more likely to be excluded [adjusted odds ratio (OR) 5.78, confidence interval 3.45–9.64, p < 0.001], but children with unrecognised difficulties [adjusted OR 3.58 (1.46–8.81) p < 0.005] or recognised subclinical difficulties [adjusted OR 3.42 (2.04–5.73) p < 0.001] were also more likely to be excluded than children with no difficulties. Children with conduct disorder and attention deficit hyperactivity disorder were most likely to be excluded compared with other types of disorder.
Exclusion from school may result from a failure to provide timely and effective support rather than a failure to recognise psychopathology.
In recent years, researchers have been working towards creating a standard conceptual framework of food parenting. To understand how parents’ reports correspond with the proposed model, the current study examined parents’ reports of their feeding behaviours in the context of a newly established framework of food parenting.
Cross-sectional, with a two-week follow-up for a subset of the sample. Participants completed a quantitative and qualitative survey to assess food parenting. The survey included items from common food parenting instruments to measure the constructs posited in the framework. Exploratory factor analyses were conducted to ascertain which items related most closely to one another and factors were mapped on to existing constructs.
Parents of children aged 2·5–7 years (n 496). Of these, 122 completed a two-week follow-up.
Analyses revealed eleven aspects of Structure (monitoring; distraction; family presence; meal/snack schedule; unstructured practices; healthy/unhealthy food availability; food preparation; healthy/unhealthy modelling; rules), ten aspects of Coercive Control (pressure to eat; using food to control emotions; food incentives to eat; food incentives to behave; non-food incentives to eat; restriction for health/weight; covert restriction; clean plate; harsh coercion) and seven aspects of Autonomy Promotion (praise; encouragement; nutrition education; child involvement; negotiation; responsive feeding; repeated offering). Content validity, assessed via parents’ open-ended explanations of their responses, was high, and test–retest reliability was moderate to high. Structure and Autonomy Promoting food parenting were highly positively correlated.
In general, parents’ responses provided support for the model, but suggested some amendments and refinements.
Des études expérimentales sont réalisées afin de préciser les relations entre la vermiculitisation des biotites (ouverture par NaCl N) et les phénomènes d'oxydation (par l'eau ou par H2O2). Les évolutions sont suivies par diffraction des rayons X et en spectroscopie d'absorption infra-rouge; l'oxydation du fer est appréciée sur l'échantillon par spectroscopie Mössbauer. Les résultats montrent que si une certaine oxydation accompagne normalement la vermiculitisation, une oxydation intense provoque une expulsion de fer et la formation de vermiculite hydroxy ferrique.
Genetic engineering is a powerful new technology that makes possible rapid development of herbicide tolerances in superior crop varieties. Use of the technology will have a major impact on future agricultural practices and the agrichemical industry. Possible risks as well as significant likely benefits – to agricultural users, corporate suppliers, and the environment – are discussed. Increased product lifetimes, decreased costs, and increased usefulness of broad-spectrum, high-potency, environmentally safe herbicides and herbicide combinations are predicted.
Techniques for preventing crazyweed toxicity in livestock have generally fallen into two categories: excluding livestock access to infested ranges during early spring and fall, and controlling crazyweed populations through herbicide application. Although picloram has been used to control crazyweed effectively in the past, aminopyralid has shown efficacy at lower application rates, exhibits less potential off-target movement, and has been classified as a reduced-risk product. Differences in the response of silky crazyweed and nontarget grasses and forbs to picloram + 2,4-D and aminopyralid + 2,4-D were investigated. Picloram + 2,4-D was applied at a rate of 0.3 kg ae ha−1 picloram + 1.1 kg ae ha−1 2,4-D, and aminopyralid + 2,4-D was applied at a rate of 0.1 kg ae ha−1 aminopyralid + 1.2 kg ae ha−1 2,4-D. Silky crazyweed canopy cover, number of flowering stalks, plant size, and biomass decreased 15 mo after herbicide treatments (MAT) with average percentage of relative reductions of 92, 95, 90, and 99%, respectively. Crazyweed density decreased by 1.5 ± 0.2 SE plants m−2 and 1.3 ± 0.2 plants m−2, a relative reduction of 95 and 80%, 15 MAT in aminopyralid + 2,4-D– and picloram + 2,4-D–treated plots, respectively. Plots treated with aminopyralid + 2,4-D had 4% lower nontarget forb canopy cover than did picloram + 2,4-D plots 15 MAT. Grass biomass remained similar within treatments over time for control, aminopyralid + 2,4-D and picloram +2,4-D plots, and was similar in all plots 15 MAT. Plots treated with herbicides had, on average, 11% greater grass cover than did control plots 15 MAT (aminopyralid + 2,4-D: 89%; picloram + 2,4-D: 85%; control: 76%).
Low income is a widely studied risk factor for child and adolescent
behavioural difficulties. Previous research on this relationship has
produced mixed findings.
To investigate the level, shape and homogeneity of income gradients in
different types of antisocial behaviour.
A representative sample of 7977 British children and adolescents, aged
5–16 years, was analysed. Hypotheses concerning the shapes and
homogeneity of the relationships between family socioeconomic status and
multiple antisocial behaviour outcomes, including clinical diagnoses of
oppositional-defiant disorder, conduct disorder and symptom subscales,
such as irritability and hurtfulness, were tested by structural equation
Consistent income gradients were demonstrated across all antisocial
behaviours studied. Disorder prevalence and mean symptom counts decreased
across income quintiles in a non-linear fashion.
Our findings emphasise that income gradients are similar across different
forms of antisocial behaviour and indicate that income may lead to
greater behavioural differences in the mid-income range and less
variation at low- and high-income extremes.
Probit analysis identified factors that influence the adoption of precision farming technologies by Southeastern cotton farmers. Younger, more educated farmers who operated larger farms and were optimistic about the future of precision farming were most likely to adopt site-specific information technology. The probability of adopting variable-rate input application technology was higher for younger farmers who operated larger farms, owned more of the land they farmed, were more informed about the costs and benefits of precision farming, and were optimistic about the future of precision farming. Computer use was not important, possibly because custom hiring shifts the burden of computer use to agribusiness firms.
There is little research on children's positive attributes and their
association with psychiatric outcomes.
To examine the hypothesis that children's positive attributes are
associated with a reduced risk of developing psychopathology in
Positive attributes, measured with the Youth Strengths Inventory (YSI)
and psychiatric outcomes were assessed on two occasions over 3 years in a
large epidemiological sample of British children and adolescents
(n = 5325).
The YSI showed high to moderate cross-informant correlations and
longitudinal stability. Children scoring high on positive attributes at
baseline had fewer psychiatric symptoms and disorders at follow-up,
adjusting for symptoms at baseline, disorder at baseline and child and
family factors. Analyses with propensity score matching also suggested
that positive attributes decrease the likelihood of psychiatric
Children's positive attributes are associated with significantly less
psychopathology across time and may be a target for intervention.
Teacher-pupil relationships have been found to mediate behavioural,
social and psychological outcomes for children at different ages
according to teacher and child report but most studies have been
To explore later psychiatric disorder among children with problematic
Secondary analysis of a population-based cross-sectional survey of
children aged 5-16 with a 3-year follow-up.
Of the 3799 primary-school pupils assessed, 2.5% of parents reported
problematic teacher-pupil relationships; for secondary-school pupils
(n=3817) this rose to 6.6%. Among secondary-school
pupils, even when children with psychiatric disorder at baseline were
excluded and we adjusted for baseline psychopathology score, problematic
teacher-pupil relationships were statistically significantly related to
higher levels of psychiatric disorder at 3-year follow-up (odds ratio
(OR) = 1.93, 95% CI 1.07-3.51 for any psychiatric disorder, OR=3.00, 95%
CI 1.37-6.58 for conduct disorder). Results for primary-school pupils
were similar but non-significant at this level of adjustment.
This study underlines the need to support teachers and schools to develop
positive relationships with their pupils.
British local authorities are required to monitor the mental health of
looked after children using mean Strengths and Difficulties Questionnaire
(SDQ) scores from parents or carers. This assumes that differences in mean
SDQ scores reflect genuine differences in child mental health in this group,
something we examined using nationally representative surveys
(n = 1391, age 5–16). We found that the SDQ was a
genuinely dimensional measure of mental health in these children and
provided accurate estimates of disorder prevalence.
Participant drop-out occurs in all longitudinal studies, and if
systematic, may lead to selection biases and erroneous conclusions being
drawn from a study.
We investigated whether drop out in the Avon Longitudinal Study of
Parents And Children (ALSPAC) was systematic or random, and if
systematic, whether it had an impact on the prediction of disruptive
Teacher reports of disruptive behaviour among currently participating,
previously participating and never participating children aged 8 years in
the ALSPAC longitudinal study were collected. Data on family factors were
obtained in pregnancy. Simulations were conducted to explain the impact
of selective drop-out on the strength of prediction.
Drop out from the ALSPAC cohort was systematic and children who dropped
out were more likely to suffer from disruptive behaviour disorder.
Systematic participant drop-out according to the family variables,
however, did not alter the association between family factors obtained in
pregnancy and disruptive behaviour disorder at 8 years of age.
Cohort studies are prone to selective drop-out and are likely to
underestimate the prevalence of psychiatric disorder. This empirical
study and the simulations confirm that the validity of regression models
is only marginally affected despite range restrictions after selective