Thermal degradation in oxygen of polymers with aromatic rings in the chain

The thermal degradation in oxygen of fifteen polymers containing aromatic rings in the chain has been studied by a weight loss method. The relative thermal stabilities of the different polymers have been determined and, where possible, the overall activation energy for breakdown. The results have been compared with those for samples of the same polymers degraded in vacuum. The most thermally stable of the polymers examined under oxidizing conditions was poly(2,6-dichlorophenylene oxide), with a stability comparable with that of a copolymer of tetrafluoroethylene and hexafluoropropylene.     

Water Resistance of Poly(Imide-Siloxane) Adhesives: Diffusion Coefficients by Gravimetric Sorption

Diffusion coefficients of water vapor in a polyimide homopolymer and poly(imide-siloxane) multi-block copolymers of different siloxane concentration were determined from gravimetric sorption experiments. Diffusion coefficients were of the order of magnitude of 10^-8 cm²/sec. Higher levels of siloxane incorporation caused a definite increase in the diffusion coefficient, indicating a decreased resistance to water ingression. The increase in diffusion was found to be influenced by siloxane block length and was interpreted in terms of free volume and morphology. The diffusion coefficient of the 10-weight-percent PDMS copolymer, however, was found to be the same within error as that of the polyimide. This and a previous surface study suggested that an increased surface water resistance may be achieved at low siloxane concentrations without greatly increasing the bulk diffusive properties to undesirable levels.     

Priorities and preferences in conflict resolution

In this study the planning process is applied to a conflict resolution problem by structuring a well known conflict (the Northern Ireland problem) using the levels of a conceptual hierarchy. The parties to the conflict form the first level, the objectives of these parties form the second level, and possible political solutions to the problem are at the third and final level.This present model is an update of an earlier analysis, carried out in 1976 and 1977, in which it was shown that the outcome which would to the greatest possible extent satisfy the aspirations of all parties would be legislative independence for Northern Ireland. The current analysis takes into account changes which have taken place since the earlier work was performed. It is shown that the most satisfactory outcome is still one of legislative independence. However, the results suggest a short-term compromise solution. An assembly, subordinate to the British government, would also satisfy most of the basic needs of the parties, provided that such an Assembly is given a wide range of powers and a large measure of autonomy.The method used here, the Analytic Hierarchy Technique (Saaty, 1977, 1980), is easy to understand and to use, and provides an efficient method for evaluating possible solutions to a conflict.     

Postpartum depression: A critical review.

A review of the literature suggests that there are 3 types of postpartum dysphoric mood states: the maternity blues (a fairly common, transient disorder), postpartum affective psychosis (relatively rare), and postpartum depression (as many as 20% of postpartum women may develop mild to moderate depression). The etiology of postpartum depression remains unclear, although numerous biological, psychological, and sociopsychological factors have been proposed as etiologically relevant. There is some empirical support for these notions, but methodological and conceptual problems hinder the development of a coherent theoretical framework for understanding the etiology, course, and treatment of the disorder. Recent data indicate a relation between stress and depression; future research into postpartum depression is needed to determine the contribution of psychosocial factors (e.g., life events and social support). Medical complications during pregnancy, infant variables, and the effect on the infant–mother relationship also need to be studied. (3 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mutations that prevent associative learning in C. elegans.

The nematode Caenorhabditis elegans offers a promising system for the reductionist study of learning and memory. In this article, classical conditioning in C. elegans is demonstrated with a variety of associative learning assays. These assays allowed for the isolation and behavioral characterization of 2 mutant C. elegans lines impaired in associative learning. Both lines show no short-term or long-term associative conditioning; however, they appear relatively normal in tests of nonassociative learning and sensorimotor function. In combination with the well-described genetics and neuroanatomy of C. elegans, the isolation of mutants selectively, yet completely, blocked in associative learning provides the basis for an effective characterization of the cellular and molecular aspects of associative learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interpretive work in short-term individual psychotherapy: An analysis using hierarchical linear modeling.

"Work" and "resistance" responses to interpretation in short-term individual (STI) psychotherapy were examined using a hierarchical linear modeling (HLM) procedure. The relationships between interpretation characteristics and patient responses within therapy were considered. Process data were drawn from 60 STI therapy cases, 30 patients with low quality of object relations (QOR), and 30 patients with high QOR. In 4 instances, the relationships between technique and response were found to vary significantly across cases. One was identified for low QOR patients, and 3 were identified for high QOR patients. Individual differences in initial disturbance and outcome were used to account for the variation of technique-response relationships. Significant findings were limited to the high QOR sample. Initial disturbance was directly related to work in response to a transference oriented approach. The transference focus-work relationship was found to be inversely related to outcome. The results extend previous findings regarding transference technique in STI therapy with high QOR patients. Through capitalizing on within-case variation, HLM can be used to illuminate process-outcome relationships in psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)