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This study examined specific risk factors discriminating psychiatric inpatients who were never suicidal from those who reported one or more suicide attempts, and compared characteristics discriminating first-time attempters from first-time and multiple repeaters (recent attempters with one or more previous attempts).
716 inpatients admitted to the Division of Psychiatry of a University Hospital were evaluated for their suicidal history, psychiatric diagnosis, current and past stressors, and other clinical and sociodemographic risk factors.
Of the 358 attempters, 86 were first-time attempters, 219 first-time repeaters, and 53 multiple repeaters. There were significant differences between the nonattempters and the attempters in sociodemographic variables, DSM-IV-TR diagnosis (attempters were diagnosed more frequently with eating disorders, and less frequently with DSM-IV Axis II disorders than nonattempters), and clinical history. First-time attempters had fewer lifespan stressors (M=1.86; SD=0.90) than repeaters (first-time repeaters: M=2.26 [SD=0.89]; multiple repeaters: M=2.28 [SD=1.13]). Furthermore, repeaters were more likely to have personality disorders (ORs=2.71-3.83), low social support (OR=4.96-6.88), and previous hospitalizations (ORs=37.23-556.69) than first-time attempters.
In repeaters, stressors may have a specific effect and a cumulative effect. They can predispose to attempts at an earlier age and, through a process of “kindling” start a “suicide career.” Alternately, an accumulation of stressors can produce a “last straw” effect. In repeaters hospitalization can be seen as another factor contributing to the kindling phenomenon, and brief intensive care in hospital settings must be weighed accurately for efficacy and for its possible negative effects.
The authors examined the association between tobacco smoking and suicidal ideation and planning in schoolchildren from 10 countries in Africa, the Americas, and the Western Pacific region.
Data were collected through the Global school-based Student Health Survey (GSHS), a collaborative surveillance project between the World Health Organization (WHO), the United Nations, UNICEF, UNESCO, UNAIDS, and the US Centers for Disease Control and Prevention (CDC). Suicidal ideation and planning, tobacco smoking, and drug and alcohol use were included in loglinear models to analyze, separately for each sex, higher order interactions among suicidality and regional and country differences.
Schoolchildren who reported suicidal ideation and/or suicidal planning had a higher risk of smoking cigarettes even after controlling for drug and alcohol misuse. Furthermore, analyses indicated higher order interactions between suicidal ideation and planning and countries belonging to different regions with different exposure to tobacco smoking among schoolchildren.
Future studies analyzing the mechanism and sequencing of the relationship among suicidal ideation and tobacco smoking should explore cultural factors.
This presentation describes and analyses patient characteristics and service usage over one year of a cohort of people with a diagnosis of severe mental illness across England, including contacts with primary and secondary care and continuity- of-care.
Data were collected from primary care patient notes (n=1150) by trained nurses from 64 practices in England, covering all service contacts from 1st April 2008 to 31st March 2009.
The estimated national rate of patients seen only in primary care was 31.1% and rates of schizophrenia and bipolar disorder were 56.8% and 37.9%. Patients had 7,961 consultations within primary care and 1,993 contacts with mental health services (20% of the total). Of those seen in secondary care, 61% had at most two secondary care contacts recorded in primary care notes. Median consultation rates with GPs were lower than have been reported for previous years and were only slightly above the general population. Relational continuity in primary care was poor for 21% of patients (Modified Modified Continuity Index =< 0.5), and for almost a third of new referrals to mental health services the primary care record contained no information on the referral outcome.
Primary care is centrally involved in the care of people with serious mental illness, but primary care and cross- boundary continuity is poor for a substantial proportion. Research is needed to determine the impact of poor continuity on patient outcomes, and above all, the impact of new collaborative ways of working at the primary/secondary care interface
The Children of the Twins Early Development Study (CoTEDS) is a new prospective children-of-twins study in the UK, designed to investigate intergenerational associations across child developmental stages. CoTEDS will enable research on genetic and environmental factors that underpin parent–child associations, with a focus on mental health and cognitive-related traits. Through CoTEDS, we will have a new lens to examine the roles that parents play in influencing child development, as well as the genetic and environmental factors that shape parenting behavior and experiences. Recruitment is ongoing from the sample of approximately 20,000 contactable adult twins who have been enrolled in the Twins Early Development Study (TEDS) since infancy. TEDS twins are invited to register all offspring to CoTEDS at birth, with 554 children registered as of May 2019. By recruiting the second generation of TEDS participants, CoTEDS will include information on adult twins and their offspring from infancy. Parent questionnaire-based data collection is now underway for 1- and 2-year-old CoTEDS infants, with further waves of data collection planned. Current data collection includes the following primary constructs: child mental health, temperament, language and cognitive development; parent mental health and social relationships; parenting behaviors and feelings; and other socioecological factors. Measurement tools have been selected with reference to existing genetically informative cohort studies to ensure overlap in phenotypes measured at corresponding stages of development. This built-in study overlap is intended to enable replication and triangulation of future analyses across samples and research designs. Here, we summarize study protocols and measurement procedures and describe future plans.
We study the Lagrangian kinematics of steady three-dimensional Stokes flow over simple cubic (SC) and body-centred cubic (BCC) lattices of close-packed spheres, and uncover the mechanisms governing chaotic mixing in these crystalline structures. Due to the cusp-shaped sphere contacts, the topology of the skin friction field is fundamentally different to that of continuous (non-granular) media, such as open pore networks, with significant implications for fluid mixing. Weak symmetry breaking of the flow orientation with respect to the lattice symmetries imparts a transition from regular to strong chaotic mixing in the BCC lattice, whereas the SC lattice only exhibits weak mixing. Whilst the SC and BCC lattices posses the same symmetry point group, these differences are explained in terms of their space groups. This insight is used to develop accurate predictions of the Lyapunov exponent distribution over the parameter space of mean flow orientation. These results point to a general theory of mixing and dispersion based upon the inherent symmetries of arbitrary crystalline structures.
The deformation of elementary fluid volumes by velocity gradients is a key process for scalar mixing, chemical reactions and biological processes in flows. Whilst fluid deformation in unsteady, turbulent flow has gained much attention over the past half-century, deformation in steady random flows with complex structure – such as flow through heterogeneous porous media – has received significantly less attention. In contrast to turbulent flow, the steady nature of these flows constrains fluid deformation to be anisotropic with respect to the fluid velocity, with significant implications for e.g. longitudinal and transverse mixing and dispersion. In this study we derive an ab initio coupled continuous-time random walk (CTRW) model of fluid deformation in random steady three-dimensional flow that is based upon a streamline coordinate transform which renders the velocity gradient and fluid deformation tensors upper triangular. We apply this coupled CTRW model to several model flows and find that these exhibit a remarkably simple deformation structure in the streamline coordinate frame, facilitating solution of the stochastic deformation tensor components. These results show that the evolution of longitudinal and transverse fluid deformation for chaotic flows is governed by both the Lyapunov exponent and power-law exponent of the velocity probability distribution function at small velocities, whereas algebraic deformation in non-chaotic flows arises from the intermittency of shear events following similar dynamics as that for steady two-dimensional flow.
We study the mixing dynamics of solute blobs in the flow through saturated heterogeneous porous media. As the solute plume is advected through a heterogeneous porous medium it suffers a series of deformations that determine its mixing with the ambient fluid through diffusion. Key questions are the relation between the spatial disorder and the mixing dynamics and the effect of the initial solute distribution. To address these questions, we formulate the advection–diffusion problem in a coordinate system that moves and rotates along streamlines of the steady flow field. The impact of the medium heterogeneity is quantified systematically within a stochastic modelling approach. For a simple shear flow, the maximum concentration of a blob decays asymptotically as
. For heterogeneous porous media, the mixing of the solute blob is determined by the random sampling of flow and deformation heterogeneity along trajectories, a mechanism different from persistent shear. We derive explicit perturbation theory expressions for stretching-enhanced solute mixing that relate the medium structure and mixing behaviour. The solution is valid for moderate heterogeneity. The random sampling of shear along trajectories leads to a
decay of the maximum concentration as opposed to an equivalent homogeneous medium, for which it decays as
Anxiety disorders are common, and cognitive–behavioural therapy (CBT) is a first-line treatment. Candidate gene studies have suggested a genetic basis to treatment response, but findings have been inconsistent.
To perform the first genome-wide association study (GWAS) of psychological treatment response in children with anxiety disorders (n = 980).
Presence and severity of anxiety was assessed using semi-structured interview at baseline, on completion of treatment (post-treatment), and 3 to 12 months after treatment completion (follow-up). DNA was genotyped using the Illumina Human Core Exome-12v1.0 array. Linear mixed models were used to test associations between genetic variants and response (change in symptom severity) immediately post-treatment and at 6-month follow-up.
No variants passed a genome-wide significance threshold (P=5×10–8) in either analysis. Four variants met criteria for suggestive significance (P<5×10–6) in association with response post-treatment, and three variants in the 6-month follow-up analysis.
This is the first genome-wide therapygenetic study. It suggests no common variants of very high effect underlie response to CBT. Future investigations should maximise power to detect single-variant and polygenic effects by using larger, more homogeneous cohorts.
Under steady flow conditions, the topological complexity inherent to all random three-dimensional (3D) porous media imparts complicated flow and transport dynamics. It has been established that this complexity generates persistent chaotic advection via a 3D fluid mechanical analogue of the baker’s map which rapidly accelerates scalar mixing in the presence of molecular diffusion. Hence, pore-scale fluid mixing is governed by the interplay between chaotic advection, molecular diffusion and the broad (power-law) distribution of fluid particle travel times which arise from the non-slip condition at pore walls. To understand and quantify mixing in 3D porous media, we consider these processes in a model 3D open porous network and develop a novel stretching continuous time random walk (CTRW), which provides analytic estimates of pore-scale mixing which compare well with direct numerical simulations. We find that the chaotic advection inherent to 3D porous media imparts scalar mixing which scales exponentially with the longitudinal advection, whereas the topological constraints associated with two-dimensional porous media limit the mixing to scale algebraically. These results decipher the role of wide transit time distributions and complex topologies on porous media mixing dynamics, and provide the building blocks for macroscopic models of dilution and mixing which resolve these mechanisms.
Developmental psychopathologists face the difficult task of identifying the environmental conditions that may contribute to early childhood behavior problems. Highly stressed caregivers can exacerbate behavior problems, while children with behavior problems may make parenting more difficult and increase caregiver stress. Unknown is: (a) how these transactions originate, (b) whether they persist over time to contribute to the development of problem behavior and (c) what role resilience factors, such as child executive functioning, may play in mitigating the development of problem behavior. In the present study, transactional relations between caregiving stress, executive functioning, and behavior problems were examined in a sample of 1,388 children with prenatal drug exposures at three developmental time points: early childhood (birth to age 5), middle childhood (ages 6 to 9), and early adolescence (ages 10 to 13). Transactional relations differed between caregiving stress and internalizing versus externalizing behavior. Targeting executive functioning in evidence-based interventions for children with prenatal substance exposure who present with internalizing problems and treating caregiving psychopathology, depression, and parenting stress in early childhood may be particularly important for children presenting with internalizing behavior.
We previously reported an association between 5HTTLPR genotype and
outcome following cognitive–behavioural therapy (CBT) in child anxiety
(Cohort 1). Children homozygous for the low-expression short-allele
showed more positive outcomes. Other similar studies have produced mixed
results, with most reporting no association between genotype and CBT
To replicate the association between 5HTTLPR and CBT outcome in child
anxiety from the Genes for Treatment study (GxT Cohort 2,
n = 829).
Logistic and linear mixed effects models were used to examine the
relationship between 5HTTLPR and CBT outcomes. Mega-analyses using both
cohorts were performed.
There was no significant effect of 5HTTLPR on CBT outcomes in Cohort 2.
Mega-analyses identified a significant association between 5HTTLPR and
remission from all anxiety disorders at follow-up (odds ratio 0.45,
P = 0.014), but not primary anxiety disorder
The association between 5HTTLPR genotype and CBT outcome did not
replicate. Short-allele homozygotes showed more positive treatment
outcomes, but with small, non-significant effects. Future studies would
benefit from utilising whole genome approaches and large, homogenous
This was a prospective longitudinal multisite study of the effects of prenatal cocaine and/or opiate exposure on temperament in 4-month-olds of the Maternal Lifestyle Study (N = 958: 366 cocaine exposed, 37 opiate exposed, 33 exposed to both drugs, 522 matched comparison). The study evaluated positivity and negativity during The Behavior Assessment of Infant Temperament (Garcia Coll et al., 1988). Parents rated temperament (Infant Behavior Questionnaire; Rothbart, 1981). Cocaine-exposed infants showed less positivity overall, mainly during activity and threshold items, more negativity during sociability items, and less negativity during irritability and threshold items. Latent profile analysis indicated individual temperament patterns were best described by three groups: low/moderate overall reactivity, high social negative reactivity, and high nonsocial negative reactivity. Infants with heavy cocaine exposure were more likely in high social negative reactivity profile, were less negative during threshold items, and required longer soothing intervention. Cocaine- and opiate-exposed infants scored lower on Infant Behavior Questionnaire smiling and laughter and duration of orienting scales. Opiate-exposed infants were rated as less respondent to soothing. By including a multitask measure of temperament we were able to show context-specific behavioral dysregulation in prenatally cocaine-exposed infants. The findings indicate flatter temperament may be specific to nonsocial contexts, whereas social interactions may be more distressing for cocaine-exposed infants.
Neurobehavioral disinhibition (ND) is a complex condition reflecting a wide range of problems involving difficulties with emotion regulation and behavior control. Respiratory sinus arrhythmia (RSA) is a physiological correlate of emotion regulation that has been studied in a variety of at-risk populations; however, there are no studies of RSA in children with ND. Data were drawn from a prospective longitudinal study of prenatal substance exposure that included 1,073 participants. Baseline RSA and RSA reactivity to an attention-demanding task were assessed at 3, 4, 5, and 6 years. ND was assessed at ages 8/9, 11, and 13/14 years via behavioral dysregulation and executive dysfunction composite measures. Greater exposure to early adversity was related to less RSA reactivity at 3 years, increases in RSA reactivity from ages 3 to 6 years, and increased behavioral dysregulation from ages 8/9 to 13/14. RSA reactivity was examined as a moderator of the association between early adversity and changes in ND. A significant Early Adversity × RSA Reactivity quadratic interaction revealed that children with decelerations in RSA reactivity exhibited increases in behavioral dysregulation, regardless of their exposure to early adversity. However, greater exposure to early adversity was related to greater increases in behavioral dysregulation, but only if children exhibited accelerations in RSA reactivity from ages 3 to 6 years. The results contribute to our understanding of how interactions across multiple levels of analysis contribute to the development of ND.
Over 30 studies in Australasia, East Asia and the Pacific Islands region have collected and analysed parasite data to determine the ranges of individual fish, many leading to conclusions about stock delineation. Parasites used as biological tags have included both those known to have long residence times in the fish and those thought to be relatively transient. In many cases the parasitological conclusions have been supported by other methods especially analysis of the chemical constituents of otoliths, and to a lesser extent, genetic data. In analysing parasite data, authors have applied multiple different statistical methodologies, including summary statistics, and univariate and multivariate approaches. Recently, a growing number of researchers have found non-parametric methods, such as analysis of similarities and cluster analysis, to be valuable. Future studies into the residence times, life cycles and geographical distributions of parasites together with more robust analytical methods will yield much important information to clarify stock structures in the area.
Improvements in materials have played a primary role in the transition from a bare subsistence economy to current high living standards in the developed world. They will be even more important in meeting the challenges of increasing pollution, changing global climate, growing population, and increasing resource demands that humankind will face in the twenty-first century. However, the marvelous structures created by materials science are only scientific curiosities unless they can compete with (and, ultimately, supplant) existing materials and technologies by being cheaper and more useful. This chapter explores the close connection between materials and economics.
The fierce competition among materials for markets drives innovation in materials, cost reductions, and new designs both in terms of materials and in terms of the products and processes that compose US and world economic activity. The invention and discovery of new materials in the laboratory drive innovation, making possible products and processes that were only engineering dreams in the past. New products and designs require new materials, spurring innovation. Indeed, some materials have the potential to lead to more desirable products and services, decreased energy use, reduced risks to the environment and human health, and reduced consumption of scarce resources.