Non-rainfall moisture inputs in the Knersvlakte: Methodology and preliminary findings

Dew, fog/mist and water vapour adsorption, the 3 vectors by which non-rainfall water can be added to soil water, may play a critical role in ecosystem function in arid zones. This paper explores a methodology for overcoming the challenges of measuring small daily inputs of non-rainfall water in the harsh environment of the Knersvlakte on the west coast of South Africa. An automatic micro-lysimeter (MLS) – an experimental arrangement of a sensitive electro-mechanical load cell, suitable electronic amplification and signal conditioning, and a microcontroller was developed. A microcomputer was employed for overall system control and data logging. Initial field work took place between late September and November 2006 on Arizona Farm, 30 km north of Vanrhynsdorp. In March 2007, subsequent work began at the Ratelgat BIOTA observatory. Manual soil weight sampling corresponded well with theoretical dew maximums, with measured maximum and minimum dew/fog of 0.4 mm and 0.08 mm (±0.08 mm) (both in September 2006). Measurements from the first prototype MLS were marred by large (± 0.24 mm) error figures, signal dropout from the analog to digital converter, and insufficient range at the required resolution. The subsequent prototype (field tested in March 2007 and still in use) provides much smaller errors (± 0.05 mm). Calibration testing at Ratelgat indicates maximum overnight dew/fog contributions of 0.35 mm (±0.05 mm), which corresponds with theoretical calculations as well as field measurements in other arid zones. Maximum dew/fog derived soil water occurs between 07:00 and 09:15. Surprisingly, soil weight, as a consequence of dew/fog inputs, starts to increase shortly after 17:20. These are preliminary findings and longer term testing and validation are ongoing at present. The role of quartz pebbles and small succulent plants in the interception of non-rainfall water is still to be explored.Keywords: non-rainfall water, dew, fog, micro-lysimeter, Knersvlakte, West Coas

Fulfilling the promise of applied developmental science: Is it time to reconsider our approach?

The promise of applied developmental science is that we can use scientific methods to promote positive human development and improve the lives of children and families. However, the present political environment in the United States makes the creation of research-informed federal policy difficult, even when the evidence supporting a given policy is unequivocal. In this essay, we hope to begin a conversation about how we, as applied developmental scientists, may modify our approach in order to best fulfill the promise of applied developmental science. To begin this conversation, we discuss the potential for establishing long-term partnerships with smaller entities, including state and municipal governments and non-governmental organizations to narrow the gap between what we know about children and families and the policies and programs that impact them. This \u27bottom-up\u27 approach has a long lineage in applied developmental science, and is currently enjoying a renaissance through the burgeoning interest in researcher-practitioner partnerships. Whether implicitly or explicitly, these partnerships often incorporate a systems perspective on children\u27s development; here, we review why embracing a systems perspective may increase the likelihood of crafting policies and programs that can improve the lives of children and families

Dimensions of Maternal Parenting and Infants’ Autonomic Functioning Interactively Predict Early Internalizing Behavior Problems

Developmental pathways to childhood internalizing behavior problems are complex, with both environmental and child-level factors contributing to their emergence. The authors use data from a prospective longitudinal study (n = 206) to examine the associations between dimensions of caregiving experiences in the first year of life and anxious/depressed and withdrawn behaviors in early childhood. Additionally, the authors examine the extent to which these associations were moderated by infants’ autonomic functioning in the first year of life indexed using measures of respiratory sinus arrhythmia (RSA) and heart period (HP). Findings suggest that higher levels of maternal sensitivity in infancy are associated with fewer anxious/depressed and withdrawn behaviors at age 3 years. Negative intrusiveness was found to be positively associated with children’s anxious/depressed behaviors but not withdrawn behaviors. Further, moderation analyses suggested that the link between negative intrusive parenting during infancy and subsequent anxious/depressed behaviors is exacerbated for infants with average or low baseline HP and that positive engaging parenting during infancy was negatively related to withdrawn behaviors for infants demonstrating average to high levels baseline HP. Interestingly, RSA was not found to moderate the associations between parenting in infancy and later internalizing behavior problems suggesting that, during infancy, overall autonomic functioning may have greater implications for the development of internalizing behaviors than do parasympathetic influences alone. Implications of these findings and future directions for research are discussed

Ferromagnetism of 3^3He Films in the Low Field Limit

We provide evidence for a finite temperature ferromagnetic transition in 2-dimensions as $H \to 0$ in thin films of $^3$He on graphite, a model system for the study of two-dimensional magnetism. We perform pulsed and CW NMR experiments at fields of 0.03 - 0.48 mT on $^3$He at areal densities of 20.5 - 24.2 atoms/nm$^2$. At these densities, the second layer of $^3$He has a strongly ferromagnetic tendency. With decreasing temperature, we find a rapid onset of magnetization that becomes independent of the applied field at temperatures in the vicinity of 1 mK. Both the dipolar field and the NMR linewidth grow rapidly as well, which is consistent with a large (order unity) polarization of the $^3$He spins.Comment: 4 figure

An Ecological Systems Perspective on Individual Differences in Children\u27s Performance on Measures of Executive Function

The predictive validity of performance on cognitive-behavioral measures of executive function (EF) suggests that these measures index children\u27s underlying capacity for self-regulation. In this paper, we apply ecological systems theory to critically evaluate this assertion. We argue that as typically administered, standard measures of EF do not index children\u27s underlying, trait-like capacity for EF, but rather assess their state-like EF performance at a given point in time and in a particular (and often quite peculiar) context. This underscores the importance of disentangling intra-individual (i.e., state-like) and inter-individual (trait-like) differences in performance on these measures and understanding how factors at various levels of organization may contribute to both. To this end, we offer an approach that combines the collection of repeated measures of EF with a multilevel modeling framework, and conclude by discussing the application of this approach to the study of educational interventions designed to foster children\u27s EF

Fathers’ sensitive parenting and the development of early executive functioning.

Using data from a diverse sample of 620 families residing in rural, predominately low-income communities, this study examined longitudinal links between fathers’ sensitive parenting in infancy and toddlerhood and children’s early executive functioning, as well as the contribution of maternal sensitive parenting. After accounting for the quality of concurrent and prior parental care, children’s early cognitive ability, and other child and family factors, fathers’ and mothers’ sensitive and supportive parenting during play at 24-months predicted children’s executive functioning at 3-years of age. In contrast, paternal parenting quality during play at 7-months did not make an independent contribution above that of maternal care, but the links between maternal sensitive and supportive parenting and executive functioning seemed to operate in similar ways during infancy and toddlerhood. These findings add to prior work on early experience and children’s executive functioning, suggesting that both fathers and mothers play a distinct and complementary role in the development of these self-regulatory skills

Rasch analysis of the hospital anxiety and depression scale (hads) for use in motor neurone disease

<p>Abstract</p> <p>Background</p> <p>The Hospital Anxiety and Depression Scale (HADS) is commonly used to assess symptoms of anxiety and depression in motor neurone disease (MND). The measure has never been specifically validated for use within this population, despite questions raised about the scale's validity. This study seeks to analyse the construct validity of the HADS in MND by fitting its data to the Rasch model.</p> <p>Methods</p> <p>The scale was administered to 298 patients with MND. Scale assessment included model fit, differential item functioning (DIF), unidimensionality, local dependency and category threshold analysis.</p> <p>Results</p> <p>Rasch analyses were carried out on the HADS total score as well as depression and anxiety subscales (HADS-T, D and A respectively). After removing one item from both of the seven item scales, it was possible to produce modified HADS-A and HADS-D scales which fit the Rasch model. An 11-item higher-order HADS-T total scale was found to fit the Rasch model following the removal of one further item.</p> <p>Conclusion</p> <p>Our results suggest that a modified HADS-A and HADS-D are unidimensional, free of DIF and have good fit to the Rasch model in this population. As such they are suitable for use in MND clinics or research. The use of the modified HADS-T as a higher-order measure of psychological distress was supported by our data. Revised cut-off points are given for the modified HADS-A and HADS-D subscales.</p

Erratum to: Measuring callous unemotional behaviors in early childhood: Factor structure and the prediction of stable aggression in middle childhood (Journal of Psychopathology and Behavioral Assessment DOI: 10.1007/s10862-013- 9379-9)

This study sought to replicate the results of our earlier study, which were published in this Journal (Willoughby et. al 2011), that used mother-reported items from the Achenbach System of Empirically Based Assessment to develop a screening measure of callous unemotional (CU) behaviors for use with preschool-aged children. We further sought to extend those results by exploring the predictive validity of the CU measure with aggression trajectories in early-/mid-childhood. The current study involved secondary data analysis of the NICHD Study of Early Childhood and Youth Development (NICHD-SECCYD) dataset. Factor analyses included N = 1176 children who participated in the age 3 year assessment of the NICHD-SECCYD. Predictive models included N = 1081 children for whom four of the six possible teacher ratings of aggressive behavior were available from annual assessments spanning 1st-6th grades. Consistent with prior work, a three-factor confirmatory factor model, which differentiated CU from oppositional defiant (ODD) and attention deficit/hyperactive-impulsive (ADHD) behaviors, provided the best fit to the data. Among children with disorganized attachment status, the combination of high levels of mother-rated ODD behaviors and CU behaviors, was predictive of stable elevated levels of teacher-rated aggression from 1st-6th grade (predicted probability = .38, compared with a base rate of .07). These results demonstrate that CU behaviors can be reliably measured by parent report in young children and are dissociable from more commonly assessed dimensions of disruptive behavior. Three-year-old children who exhibit elevated levels of ODD and CU behaviors, and who have disorganized attachments, are at increased risk for exhibiting elevated levels of aggression across middle childhood. Results are discussed from the perspective of early assessment and intervention

Parenting and children’s representations of family predict disruptive and callous-unemotional behaviors.

Data from a large prospective longitudinal study (n = 1,239) was used to investigate the association between observed sensitive parenting in early childhood and children's representations of family relationships as measured by the Family Drawing Paradigm (FDP) in first grade as well as the extent to which these representations partially mediate the influences of early caregiving experiences on later conduct problems and callous-unemotional behaviors. A structural equation modeling approach revealed that less sensitive parenting at 24, 36, and 58 months predicts higher levels of conduct problems (CP) and callous-unemotional (CU) behaviors in first grade controlling for earlier measures of CP and CU behaviors. Results also indicated that greater dysfunctional family representations, as assessed with the FDP, are significantly associated with higher CU behaviors in the first grade, but not CP. Finally, a test of the indirect pathway suggests that children's dysfunctional family representations may, in part, account for the association between sensitive parenting and CU behaviors