Substance use disorder and posttraumatic stress disorder symptomology on behavioral outcomes among juvenile justice youth

BACKGROUND AND OBJECTIVES: Substance use behaviors have been identified as a risk factor that places juveniles at greater risk for engaging in delinquent behaviors and continual contact with the juvenile justice system. Currently, there is lack of research that explores comorbid factors associated with substance use, such as post-traumatic stress disorder (PTSD) symptoms, that could help identify youth who are at greatest risk. The aim of the present study was to examine if PTSD symptomology moderated the relationship between substance use disorder (SUD) symptoms and externalizing behaviors and commission of a violent crime; hypothesizing that risk would be heightened among youth with elevated SUD and PTSD symptomology compared to those with elevated SUD symptoms but lower PTSD symptoms. METHOD: The study included 194 predominantly male (78.4%), non-White (74.2%) juvenile justice youth between the ages of 9-18 (M = 15.36). Youth provided responses to assess PTSD symptoms, SUD symptoms, and externalizing behaviors. Commission of a violent crime was based on parole officer report. RESULTS: Findings indicated that SUD symptomology was associated with greater externalizing behaviors at high levels of PTSD symptomology. At low levels of PTSD symptomology, SUD symptoms were inversely associated with externalizing behaviors. An interactive relationship was not observed for commission of violent crimes. CONCLUSIONS: Findings suggest that the association between SUD symptoms and externalizing behaviors among juvenile offenders may be best explained by the presence of PTSD symptomology. SCIENTIFIC SIGNIFICANCE: Addressing PTSD rather than SUD symptoms may be a better target for reducing risk for externalizing behaviors among this population of youth (Am J Addict 2019;28:29-35)

Application of Geometrical Diffraction Theory to QNDE Analysis

The direct problem of the diffraction of time-harmonic·waves by cracks in elastic solids is analyzed for high-frequencies, when the wavelengths are of the same order of magnitude as a characteristic length dimension, a, of the crack. It is shown that good approximations at high frequencies can be obtained on the basis of elastodynamic ray theory. An elastodynamic version of geometrical diffraction theory is briefly reviewed. We also present a hybrid theory, wherein the crack opening displacement is computed on the basis of geometrical diffraction theory, and the scattered field is subsequently obtained by the use of a representation theorem. This hybrid approach avoids the difficulties at shadow boundaries and caustic surfaces that plague a direct application of geometrical diffraction theory. Explicit results are computed for slits and penny-shaped cracks, and these results are compared with numerical results obtained on the basis of exact integral equation formulations. The relatively simply structure of the expressions for the scattered fields displays some characteristic features, whose possible role in the inverse problem is discussed

Application of Geometrical Diffraction Theory to Scattering by Cracks

At high frequencies, the geometrical theory of diffraction provides useful and relatively simple approximations to diffracted fields. In this paper the theory is applied to the diffraction of time-harmonic longitudinal waves by a penny-shaped crack in an elastic solid

Interactive effects of elevated temperature and CO2 on two phylogeographically distinct clones of common reed (Phragmites australis)

The aboveground growth, physiological and biochemical parameters of two clones of the cosmopolitan wetland grass Phragmites australis, grown at four treatment combinations of temperature and O2, were investigated to elucidate whether their climate response differed due to inherent differences in their ecological adaptation. The two phylogeographically distinct P. australis clones (DK clone, European genetic background; ALG clone, Mediterranean genetic background) were grown for 151 days in phytotrons at 19/12 8C (day/night temperature) and 390 ppm CO2, and at elevated temperature (+5 8C) and CO2 (700 ppm) with treatment factors alone or in combination. The ALG clone had 2–4 times higher aboveground biomass, higher light-saturated rates of photosynthesis (Pmax), maximum electron transport rates (ETRmax) and Rubisco activity, and higher photosynthetic nitrogen-use efficiency than the DK clone. The DK clone, however, produced more shoots, leaves and sideshoots, and had 9–51 % higher specific leaf area and 15–39 % higher leaf nitrogen concentration than the ALG clone. Although elevated atmospheric CO2 alone barely affected the aboveground growth of the two P. australis clones, simultaneously elevated temperature and CO2 stimulated growth and aboveground biomass. Overall, elevated CO2 stimulated photosynthesis, but the clones responded differently to a concomitant increase in CO2 and temperature, depending on the phylogeographic background of the plant. The DK clone showed overall stronger responses, and can be considered the more plastic of the two clones with respect to CO2 and temperature. Thus, the DK clone may be better adapted to climate change than the ALG clone, at least in the short term

Explicit asymptotic modelling of transient Love waves propagated along a thin coating

The official published version can be obtained from the link below.An explicit asymptotic model for transient Love waves is derived from the exact equations of anti-plane elasticity. The perturbation procedure relies upon the slow decay of low-frequency Love waves to approximate the displacement field in the substrate by a power series in the depth coordinate. When appropriate decay conditions are imposed on the series, one obtains a model equation governing the displacement at the interface between the coating and the substrate. Unusually, the model equation contains a term with a pseudo-differential operator. This result is confirmed and interpreted by analysing the exact solution obtained by integral transforms. The performance of the derived model is illustrated by numerical examples.This work is sponsored by the grant from Higher Education of Pakistan and by the Brunel University’s “BRIEF” research award

Rational, computer-aided design of multi-target ligands

Over the past two decades the “one drug – one target – one disease” concept became the prevalent paradigm in drug discovery. The main idea of this approach is the identification of a single protein target whose inhibition leads to a successful treatment of the examined disease. The predominant assumption is that highly selective ligands would avoid unwanted side effects caused by binding to secondary non-therapeutic targets. In recent years the results of post-genomic and network biology showed that proteins rarely act in isolated systems but rather as a part of a highly connected network [1]. In addition this connectivity leads to more robust systems that cannot be interfered by the inhibition of a single target of that network and consequently might not lead to the desired therapeutic effect [2]. Furthermore studies prove that robust systems are rather affected by weak inhibitions of several parts than by a complete inhibition of a single selected element of that system [3]. Therefore there is an increasing interest in developing drugs that take effect on multiple targets simultaneously but is concurrently a great challenge for medicinal chemists. There has to be a sufficient activity on each target as well as an adequate pharmacokinetic profile [4]. Early design strategies tried to link the pharmacophors of known inhibitors, however these methods often lead to high molecular weight and low ligand efficacy. We present a new rational approach based on a retrosynthetic combinatorial analysis procedure [5] on approved ligands of multiple targets. These RECAP fragments are used to design a large combinatorial library containing molecules featuring chemical properties of each ligand class. The molecules are further validated by machine learning models, like random forests and self-organizing maps, regarding their activity on the targets of interest

Genetic and environmental influences on Anxious/Depression during childhood: a study from the Netherlands Twin Register

For a large sample of twin pairs from the Netherlands Twins Register who were recruited at birth and followed through childhood, we obtained parental ratings of Anxious/Depression (A/D). Maternal ratings were obtained at ages 3 years (for 9025 twin pairs), 5 years (9222 pairs), 7 years (7331 pairs), 10 years (4430 pairs) and 12 years (2363 pairs). For 60-90% of the pairs, father ratings were also available. Multivariate genetic models were used to test for rater-independent and rater-specific assessments of A/D and to determine the genetic and environmental influences on individual differences in A/D at different ages. At all ages, monozygotic twins resembled each other more closely for A/D than dizygotic twins, implying genetic influences on variation in A/D. Opposite sex twin pairs resembled each other to same extent as same-sex dizygotic twins, suggesting that the same genes are expressed in boys and girls. Heritability estimates for rater-independent A/D were high in 3-year olds (76%) and decreased in size as children grew up [60% at age 5, 67% at age 7, 53% at age 10 (60% in boys) and 48% at age 12 years]. The decrease in genetic influences was accompanied by an increase in the influence of the shared family environment [absent at ages 3 and 7, 16% at age 5, 20% at age 10 (5% in boys) and 18% at age 12 years]. The agreement between parental A/D ratings was between 0.5 and 0.7, with somewhat higher correlations for the youngest group. Disagreement in ratings between the parents was not merely the result of unreliability or rater bias. Both the parents provided unique information from their own perspective on the behavior of their children. Significant influences of genetic and shared environmental factors were found for the unique parental views. At all ages, the contribution of shared environmental factors to variation in rater-specific views was higher for father ratings. Also, at all ages except age 12, the heritability estimates for the rater-specific phenotype were higher for mother ratings (59% at age 3 and decreasing to 27% at age 12 years) than for father ratings (between 14 and 29%). Differences between children, even as young as 3 years, in A/D are to a large extent due to genetic differences. As children grow up, the variation in A/D is due in equal parts to genetic and environmental influences. Anxious/Depression, unlike many other common childhood psychopathologies, is influenced by the shared family environment. These findings may provide support for why certain family therapeutic approaches are effective in the A/D spectrum of illnesses. Copyright © Blackwell Munksgaard 2005