Associations between diurnal preference, sleep quality and externalizing behaviours: a behavioural genetic analysis

Background - Certain aspects of sleep co-occur with externalizing behaviours in youth, yet little is known about these associations in adults. The present study: (1) examines the associations between diurnal preference (morningness versus eveningness), sleep quality and externalizing behaviours; (2) explores the extent to which genetic and environmental influences are shared between or are unique to these phenotypes; (3) examines the extent to which genetic and environmental influences account for these associations. Method - Questionnaires assessing diurnal preference, sleep quality and externalizing behaviours were completed by 1556 young adult twins and siblings. Results - A preference for eveningness and poor sleep quality were associated with greater externalizing symptoms [r=0.28 (95% CI 0.23–0.33) and 0.34 (95% CI 0.28–0.39), respectively]. A total of 18% of the genetic influences on externalizing behaviours were shared with diurnal preference and sleep quality and an additional 14% were shared with sleep quality alone. Non-shared environmental influences common to the phenotypes were small (2%). The association between diurnal preference and externalizing behaviours was mostly explained by genetic influences [additive genetic influence (A)=80% (95% CI 0.56–1.01)], as was the association between sleep quality and externalizing behaviours [A=81% (95% CI 0.62–0.99)]. Non-shared environmental (E) influences accounted for the remaining variance for both associations [E=20% (95% CI −0.01 to 0.44) and 19% (95% CI 0.01–0.38), respectively]. Conclusions - A preference for eveningness and poor sleep quality are moderately associated with externalizing behaviours in young adults. There is a moderate amount of shared genetic influences between the phenotypes and genetic influences account for a large proportion of the association between sleep and externalizing behaviours. Further research could focus on identifying specific genetic polymorphisms common to both sleep and externalizing behaviours

The Genesis 12–19 (G1219) Study: A Twin and Sibling Study of Gene–Environment Interplay and Adolescent Development in the UK

The Genesis 12–19 (G1219) Study is an ongoing longitudinal study of a sample of UK twin pairs, non-twin sibling pairs, and their parents. G1219 was initially designed to examine the role of gene–environment interplay in adolescent depression. However, since then data have continued to be collected from both parents and their offspring into young adulthood. This has allowed for longitudinal analyses of depression and has enabled researchers to investigate multiple phenotypes and to ask questions about intermediate mechanisms. The study has primarily focused on emotional development, particularly depression and anxiety, which have been assessed at multiple levels of analysis (symptoms, cognitions, and relevant environmental experiences). G1219 has also included assessment of a broader range of psychological phenotypes ranging from antisocial behaviors and substance use to sleep difficulties, in addition to multiple aspects of the environment. DNA has also been collected. The first wave of data collection began in the year 1999 and the fifth wave of data collection will be complete before the end of 2012. In this article, we describe the sample, data collection, and measures used. We also summarize some of the key findings to date

Analysis of Bond-Stiffness Deterioration due to Distributed Disbonds

This paper is concerned with the characterization of residual adhesive strength. The deterioration of adhesive strength depends on damage mechanisms in thin layers at the interfaces of adherends and adhesives. In this work adhesive-bond damage mechanisms, particularly distributions of disbonds, are modeled and related to nonlinear changes of the gross stiffness of the adhesive layer. In turn, the changes in adhesive-layer stiffness affect coefficients of reflection and transmission for reflection and transmission of ultrasonic signals by the adhesive-bond layer. Hence the reflection and transmission measurements can be used to characterize adhesive bond damage

Persistence of Problematic Sexual Behaviors in Children

The purpose of this study was to identify personal and family predictors and correlates of persistence of problematic sexual behaviors (PSB) in children. Participants were the families of 49 children (ages 4–11 years) referred by Child Protective Services in 4 administrative districts of Quebec. Caregivers completed interviews and questionnaires twice at a 1-year interval. Results showed that 43% of children persisted with PSB. When age was controlled, greater exposure to sexualized behaviors in the family proved both a correlate and a predictor of PSB persistence in children 12 months later.\ud Externalizing problems and somatic complaints emerged as correlates of PSB as well. Maltreatment subtypes did not predict PSB persistence

Ultrasonic Evaluation of Damage in Concrete Bridge Deck Pavements

Interest in repair, maintenance and characterization of infrastructure in the United States has reached unprecedented highs in recent years. The interest in this area is motivated by the aging and associated degradation of our built environment. There is also a perception that the complexity of the problems encountered in this area are a suitable venue for application of new technology from academic and defense related research. However, while applying established technological solutions to the challenges encountered in infrastructure research, basic questions are encountered regarding the nature of the materials used in roads, bridges and other structures. In spite of the enormous experience base with many of the materials used in infrastructure, often the behavior of the materials has only been understood in terms of the gross behavior in large scale measurements. The materials often show a large variation in their properties between samples as well as a large spatial variation in properties in a single sample. Perhaps the most important material, concrete, may also be the most variable material used in infrastructure

Tissue remodeling macrophages morphologically dominate at the interface of polypropylene surgical meshes in the human abdomen

Background Mesh implants are widely used to reinforce the abdominal wall, although the inevitable inflammatory foreign body reaction (FBR) at the interface leads to complications. Macrophages are suspected to regulate the subsequent scar formation, but it is still unclear whether adequate fibrous scar formation with collagen deposition depends mainly on the presence of M1 or M2 macrophages. Methods This study investigated the FBR to seven human polypropylene meshes, which were removed after a median incorporation time of 1 year due to the primary complaint of recurrence. Using immunofluorescence, the FBR was examined in six regional zones with increasing distance from the mesh fibers up to 350 µm, based on the cell densities, macrophage M1 (CD86) and M2 (CD163, CD206) phenotypes, deposition of collagen-I and -III, and expression of matrix metalloproteinase-2 (MMP-2) and -8 as indicator of collagen degradation. Results All mesh–tissue complexes demonstrated a decrease in cell density and macrophages with distance to the mesh fibers. Overall, about 60% of the macrophages presented an M2 phenotype, whereas only 6% an M1 phenotype. Over 70% of macrophages showed co-expression with collagen-I or -III and over 50% with MMP-2. Conclusions The chronic FBR to polypropylene meshes is associated with an M2 macrophage response, which is accompanied by collagen deposition and MMP-2 expression. These findings challenge the idea that mainly M1 macrophages are related to inflammation and highlights that iatrogenic attempts to polarize these cells towards the M2 phenotype may not be a solution to ameliorate the long-term foreign body reaction

Wavelet analysis of beam-soil structure response for fast moving train

This paper presents a wavelet based approach for the vibratory analysis of beam-soil structure related to a point load moving along a beam resting on the surface. The model is represented by the Euler-Bernoulli equation for the beam, elastodynamic equation of motion for the soil and appropriate boundary conditions. Two cases are analysed: the model with a half space under the beam and the model where the supporting medium has a finite thickness. Analytical solutions for the displacements are obtained and discussed in relation to the used boundary conditions and the type of considered loads: harmonic and constant. The analysis in time-frequency and velocity-frequency domains is carried out for realistic systems of parameters describing physical properties of the model. The approximate displacement values are determined by applying a wavelet method for a derivation of the inverse Fourier transform. A special form of the coiflet filter used in numerical calculations allows to carry out analysis without loss of accuracy related to singularities appearing in wavelet approximation formulas, when dealing with standard filters and complex dynamic systems. © 2009 IOP Publishing Ltd

Disclosure of Maternal HIV Status to Children: To Tell or Not To Tell . . . That Is the Question

HIV-infected mothers face the challenging decision of whether to disclose their serostatus to their children. From the perspective of both mother and child, we explored the process of disclosure, providing descriptive information and examining the relationships among disclosure, demographic variables, and child adjustment. Participants were 23 mothers and one of their noninfected children (9 to 16 years of age). Sixty-one percent of mothers disclosed. Consistent with previous research, disclosure was not related to child functioning. However, children sworn to secrecy demonstrated lower social competence and more externalizing problems. Differential disclosure, which occurred in one-third of the families, was associated with higher levels of depressive and anxiety symptoms. Finally, knowing more than mothers had themselves disclosed was related to child maladjustment across multiple domains. Clinical implications and the need for future research are considered

Complex Wave Numbers in the Vicinity of the Schwarzschild Event Horizon

This paper is devoted to investigate the cold plasma wave properties outside the event horizon of the Schwarzschild planar analogue. The dispersion relations are obtained from the corresponding Fourier analyzed equations for non-rotating and rotating, non-magnetized and magnetized backgrounds. These dispersion relations provide complex wave numbers. The wave numbers are shown in graphs to discuss the nature and behavior of waves and the properties of plasma lying in the vicinity of the Schwarzschild event horizon.Comment: 21 pages, 9 figures, accepted for publication Int. J. Mod. Phys.

Child Psychosocial Adjustment and Parenting in Families Affected by Maternal HIV/AIDS

Child adjustment and parenting were examined in 23 9-through 16-year-old youth from families affected by maternal HIV infection and 20 same-age peers whose mothers were not infected. Children whose mothers were seropositive reported significantly more externalizing problems. Infected mothers reported less age-appropriate supervision/monitoring relative to non-infected mothers. Better mother-child relationship quality and less impairment in parental supervision/monitoring of age-appropriate youth behaviors were associated with fewer externalizing difficulties among the HIV-positive group only. Similarly, only among HIV-infected mothers was refraining from engaging in inconsistent disciplinary tactics associated with lower reports of internalizing and externalizing problems. These data highlight the promise of programs targeting parenting skills to prevent or ameliorate child difficulties