Maternal resolution of child diagnosis: Stability and relations with child attachment across the toddler to preschooler transition.

In this longitudinal study, the authors investigated individual differences in how families adapt to a child's congenital disorder. Family impact, maternal grief resolution, and child attachment were assessed among 74 mothers and their toddlers with a neurological disorder or disfigurement. Fifty dyads were reevaluated 16 months later. For children with neurological compared with disfigurement diagnoses, there was a greater likelihood of negative impact on family, unresolved maternal grief, and insecure attachment at Time 1. Children classified as secure were significantly more likely to have mothers classified as resolved regarding their reactions to their children's diagnosis. Maternal grief resolution was significantly stable (77%) over time and mediated the relation between type of diagnosis and child security. With time, negative impact of child condition on the family decreased and percentage of children classified as secure increased, suggesting that on average families improved. Results suggest that helping parents come to terms emotionally and cognitively with their child's condition may be a useful focus for intervention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatially resolved in vitro molecular ecology

Sensitive CCD-based fluorescence detection has made spatially resolved studies of evolving cell-free molecular systems possible. In recent years our attention has focussed on making the transition to open and interacting spatially-resolved amplification systems using silicon microreactor technology and on providing a hardware platform for individual based simulation of such systems. Significant progress has been achieved in this direction. Open microflow reactors have been realized in zero (well-mixed), one and two dimensions with volumes small enough to allow long-time studies with limited biochemical materials. The primer directed 3SR reaction (amplifying DNA and RNA) has been used as a basis for constructing interacting model systems with both predator-prey and cooperative amplification character. Theoretical work has demonstrated the need for individual based modeling of such systems: a significant fraction of the population consists of distinct sequence polymers in any case. A massively parallel processor-configurable computer NGEN has been designed and constructed which allows the high speed simulation in hardware of relatively large populations of locally interacting individual strings of chosen length (e.g. up to 2000*2000 for 64 bases), in addition to its application as an evolvable hardware machine. Simulations show self-replicating spots to stabilize the cooperative amplification in evolving systems (a mechanism proposed by the author in 1994). Both oscillatory kinetics and pattern formation are expected in the experimental model systems under investigation which profoundly affect the course of evolution. Such in vitro model systems serve both to test current theories of cooperative evolution and provide clues for optimisation strategies in molecular biotechnology.     

Personality predictors of mood related to dieting

The clinical utility of a model of normal emotional functioning (vs. psychopathology) and the moderating effects of neuroticism (N) and extraversion (E) on mood were examined during a 6-week weight-loss trial. Participants were 40 obese women who completed measures of negative affect (NA) and positive affect (PA) weekly during the diet and measures of anxiety and depression (Beck Depression Inventory [BDI]) at pre-, mid-, and postdiet. Results indicated that (a) average NA and PA were each uniquely related to postdiet BDI scores, (b) N was significantly related to NA during the diet and postdiet BDI scores, and (c) N and E interacted to predict PA during the diet. The results suggest that assessment of personality and normal mood variation may be useful additions to weight-loss intervention and research.     

Homeless and matched housed adolescents: a comparative study of psychopathology

Compared a probability sample of 118 homeless adolescents (ages 12-17) from 6 shelters from throughout the 7-county Detroit metropolitan area to a matched sample of 118 housed adolescents using the Diagnostic Interview Schedule for Children (DISC), which yields diagnoses based on the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; DSM-III-R; American Psychiatric Association, 1987) criteria, and the Brief Symptom Inventory (BSI). Adolescents in the housed comparison group were matched on age, sex, race, and neighborhood characteristics. Analyses, including ones controlling for a set of 10 risk and resilience factors, indicated that the homeless showed more disruptive behavior disorders and alcohol abuse or dependence on the DISC and greater levels of symptomatology on the BSI. There were no significant group differences on drug abuse or affective disorders, and psychotic disorders were rare in both groups. This pattern of findings is not entirely consistent with popular stereotypes about homeless youth nor with many existing studies (which have often failed to include an appropriate comparison group).     

A model of S,P and N uptake by a perennial pasture

An approach is presented for simulating the uptake of S, P and N by a perennial pasture, based upon diffusion theory and plant uptake kinetics. Plant uptake was limited by either (i) diffusion to the root, (ii) root uptake capacity, or (iii) plant demand. For S and P, uptake as limited by diffusion was calculated from the nutrient depletion pattern around the root, which is dependent upon soil diffusivity for the anion, and the length of time since the root grew into the new soil. To avoid time-consuming calculations at various uptake times and distances from the root, the nutrient depletion pattern was simplified into an effective rooting radius, whereby all plant-available nutrient within the radius was made available to the plant over a 30 day period, and none from outside the radius. Mycorrhizal enhancement of P uptake was simulated by increasing the radius by a factor of between 1 and 3 when P was the primary limiting nutrient. Limitations (ii) and (iii) were included for S and P for the rare occasions when nutrient concentrations were high either in a single layer, or in the profile overall. For N, uptake was limited by uptake capacity, adjusted for soil N concentration, root length density and soil moisture content.Because of a lack of data on diffusion coefficients close to the plant root, a calibration factor was applied to the effective rooting radius, which is described in the second paper in the series.