Aggregation morphology of planar engineered nanomaterials.

In this investigation, the utility of a static light scattering (SLS) technique to characterize aggregate morphology of two-dimensional engineered nanomaterials (2D ENMs) was systematically evaluated. The aggregation of graphene oxide (GO) and lithiated-molybdenum disulfide (Li-MoS2) were measured and compared to that of a spherical reference colloid, carboxylate-modified latex (CML) nanoparticles. The critical coagulation concentration (CCC) for all dispersions was determined via analysis of aggregation kinetics using time-resolved dynamic light scattering. This technique allowed for the elucidation of the transition from the reaction-limited aggregation (RLA) regime to diffusion-limited aggregation (DLA). The findings of this study support the aggregation trends predicted by Derjaguin-Landau-Verwey-Overbeek (DLVO) theory and recent computer simulations of aggregation kinetics. For all nanomaterials, as ionic strength increased towards the respective the CCC, fractal dimension decreased; any increase in ionic strength beyond the CCC did not yield significant change in fractal dimension. Across comparable primary particle sizes and using both carbonaceous (GO) and inorganic (Li-MoS2) 2D ENMs, this study further supports the use of SLS for the measurement of fractal dimension for 2D materials. To further support this claim, the aggregate morphology of GO in both RLA and DLA regimes was measured via cryogenic transmission electron microscopy.

Does maintenance treatment matter?

This study examined the effects of a two-year maintenance treatment assessed at 1 and 2 years following Parent-child Interaction Therapy (PCIT). Sixty-one of 100 clinic-referred children (M age = 4 years, 4 months) originally diagnosed with oppositional defiant disorder (ODD) completed the standard treatment and were then randomized to PCIT maintenance treatment (MT) or to an assessment-only follow-up condition (AO). Rating scale and observational measures from fathers, mothers, and children were collected before and after standard treatment and at one- and two-year follow-up assessments. Maintenance treatment involved monthly telephone contacts from the original therapist focused on relapse prevention based on principles of PCIT. At the two-year follow-up, MT families showed few changes from post-treatment, as expected. However, the expected decrements for AO control families were not seen. Few differences between MT and AO were found at either follow-up assessment, and there were no significant differences in the rates of change during follow-up. The maintenance of gains among AO families may have resulted from the continuous enhancement of standard treatment or from inadvertent reinforcement for maintenance provided by the assessments of change alone.

The community-based healthy-lifestyle intervention for rural preschools (CHIRP) study: design and methods.

The CHIRP study is a two-arm, pilot randomized controlled trial assessing the effectiveness of a behavioral family weight management intervention in an important and at-risk population, overweight young children, 3 to 6 years of age, and their parents from underserved rural counties. Participants will include 96 parent-child dyads living in rural counties in north central Florida. Families will be randomized to one of two conditions: (a) behavioral family based intervention or (b) a waitlist control. Child and parent participants will be assessed at baseline (month 0), post-treatment (month 4), and follow-up (month 10). Assessments and intervention sessions will be held at the Cooperative Extension office in each participating rural county. The primary outcome measure is change in child body mass index (BMI) z-score. Additional key outcome measures include child dietary intake, physical activity, and parent BMI. This study is unique because (1) it is one of the few randomized controlled trails examining a behavioral family intervention to address healthy habits and improved weight status in young overweight and obese children, (2) addresses health promotion in rural settings, and (3) examines intervention delivery in real world community settings through the Cooperative Extension Service offices. If successful, this research has potential implications for medically underserved rural communities and preventative health services for young children and their families.

Evidence-Based School Behavior Assessment of Externalizing Behavior in Young Children.

This study examined the psychometric properties of the Revised Edition of the School Observation Coding System (REDSOCS). Participants were 68 children ages 3 to 6 who completed parent-child interaction therapy for Oppositional Defiant Disorder as part of a larger efficacy trial. Interobserver reliability on REDSOCS categories was moderate to high, with percent agreement ranging from 47% to 90% (M = 67%) and Cohen's kappa coefficients ranging from .69 to .95 (M = .82). Convergent validity of the REDSOCS categories was supported by significant correlations with the Intensity Scale of the Sutter-Eyberg Student Behavior Inventory-Revised and related subscales of the Conners' Teacher Rating Scale-Revised: Long Version (CTRS-R: L). Divergent validity was indicated by nonsignificant correlations between REDSOCS categories and scales on the CTRS-R: L expected not to relate to disruptive classroom behavior. Treatment sensitivity was demonstrated for two of the three primary REDSOCS categories by significant pre to posttreatment changes. This study provides psychometric support for the designation of REDSOCS as an evidence-based assessment procedure for young children.

Evidence-based psychosocial treatments for children and adolescents with disruptive behavior.

This article reviews the literature from 1996 to 2007 to update the 1998 Brestan and Eyberg report on evidence-based psychosocial treatments (EBTs) for child and adolescent disruptive behavior, including oppositional defiant disorder and conduct disorder. Studies were evaluated using criteria for EBTs developed by the task force on promotion and dissemination of psychological procedures (Chambless et al., 1998; Chambless et al., 1996). Sixteen EBTs were identified in this review, up from 12 in the earlier report, and 9 "possibly efficacious" treatments (Chambless & Hollon, 1998) were identified as well. This article describes the EBTs and their evidence base and covers research on moderators and mediators of treatment outcome, as well as the clinical representativeness and generalizability of the studies. Best practice recommendations from the current evidence base also are offered, as well as calls for future research that increases understanding of the moderators and mechanisms of change for children and adolescents with disruptive behavior disorders.

Predicting outcome in parent-child interaction therapy: success and attrition.

This study explored predictors of treatment response and attrition in Parent-Child Interaction Therapy (PCIT). Participants were 99 families of 3- to 6-year-old children with disruptive behavior disorders. Multiple logistic regression was used to identify those pretreatment child, family, and accessibility factors that were predictive of success or attrition. For all study participants, waitlist group assignment and maternal age were the significant predictors of outcome. For treatment participants (study participants excluding those who dropped out after the initial evaluation but before treatment began), only maternal ratings of parenting stress and maternal inappropriate behavior during parent-child interactions were significant predictors of treatment outcome. These results suggest that for treatment studies of disruptive preschoolers, the benefits of using a waitlist control group may be outweighed by the disproportionate number of dropouts from this group. Once families begin PCIT, however, parent-related variables become salient in predicting treatment outcome.

Verbal memory abilities of children with brain tumors.

Several critical neuroanatomical structures and pathways for memory performance are located in the third ventricle region. This led us to predict that verbal memory abilities would be more impaired in children treated for third ventricle tumors compared to those treated for cerebellar tumors. Archival data was obtained from 24 pediatric patients with third ventricle region tumors and 18 pediatric patients with cerebellar tumors. Neuroradiological verifications of tumor involvement and hydrocephalus severity (i.e., Evans Index) on preoperative scans and MRIs proximal to the time of the neuropsychological evaluation were conducted. The potential confounds of hydrocephalus severity, seizure medication, age, radiation treatment, and chemotherapy were addressed. Verbal IQ was comparable between tumor groups and in the Average range. The third ventricle region group performed significantly worse on list learning and delayed list recall compared to the cerebellar group. Their mean performance was in the clinically impaired range on both trials. The third ventricle region tumor group performed better than the cerebellar tumor group on Digit Span, a basic repetition, attention span task. These findings support the hypothesis that pediatric patients with third ventricle region brain tumors are more likely to be impaired on verbal recall tasks compared to pediatric patients with cerebellar brain tumors. In contrast, patients who were treated for cerebellar tumors were more impaired on the basic repetition, attention span task compared to patients who were treated for third ventricle tumors. Future studies should examine the specific neuroanatomical structures and pathways that are damaged and may influence differential cognitive impairments in children.