Using finite element modeling to examine the flow processes in quasi-constrained high-pressure torsion

Finite element modeling was used to examine the flow processes in high-pressure torsion (HPT) when using quasi-constrained conditions where disks are contained within depressions on the inner surfaces of the upper and lower anvils. Separate simulations were performed using applied pressures from 0.5 to 2.0 GPa, rotations up to 1.5 turns and friction coefficients from 0 to 1.0 outside of the depressions. The simulations demonstrate the distribution of effective strain within the depressions is comparable to the prediction by ideal torsion, and the applied pressure and the friction coefficient outside the depressions play only a minor role in the distribution of effective strain. The mean stresses during processing vary linearly with the distance from the center of the disk such that there are higher compressive stresses in the disk centers and lower stresses at the edges. The torque required for rotation of the anvil is strongly dependent upon the friction coefficient between the sample and the anvil outside the depressions.     

Disorders of adult attachment.

This article presents an overview of J. Bowlby's framework of attachment (e.g., 1990) for conceptualizing adult psychopathology and its application to clinical practice. The theory proposes that psychological disorders reflect an internalization of adverse attachment experiences, both current and past, and in particular those that undermine self-reliance and feelings of security. Clinical syndromes indicate intensification of anxiety, depression, and/or anger to a degree which interferes with adaptive functioning and interactions with others. The secure base of therapy provides a new model of what close relationships can be like, as well as a setting for exploring and possibly modifying the meaning given to separation and loss experiences. Issues of prevention and social policy are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comments on “Probability estimation in arithmetic andadaptive-Huffman entropy coders”

This comment points out some omissions in the work of Duttweiler and Chazmas (see ibid., vol.4, p.237, 1995) on credit related to scaled-count estimators that perform count-scaling when the count of the less probable symbol (LPS) reaches a limiting value     

Attachment, detachment and borderline personality disorder.

In an attempt to expand understanding of more severe pathology, attachment theory, developed by John Bowlby, is applied to borderline personality disorder in adults. Conceptualized as a condition of profound insecure attachment, with extreme vacillations between a desire for proximity and attachment and a dread and avoidance of engagement, borderline pathology reflects traumatic attachment experiences, beginning early in life. Besides the importance of trauma, disturbances in affect regulation and cognitive distortions are emphasized. The secure base of a therapeutic bond provides consistency, reliability, and affirmation while encouraging exploration of separation and loss experiences, both current and past, in order to modify inner working models of oneself and relationships with others. Implications for prevention are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Superplasticity in ceramics

It is now recognized that superplasticity is a potential deformation process in ceramics. This review summarizes the major characteristics of superplasticity and examines the reports of both transformation and structural superplasticity in ceramic and other non-metallic materials. It is shown that there are both similarities to and differences from metals. Similarities include the variation of strain rate with stress and grain size, but an important difference is the necessity to consider the role of intergranular glassy phases in ceramics. Superplasticity is also important in intermetallic compounds, and in geological materials where there is evidence for superplastic deformation both in laboratory experiments and in natural deformation.     

Endogenous depression in the elderly: Prevalence and agreement among measures.

Describes agreement among diagnoses made according to 5 definitions of endogenous depression in a sample of 99 depressed elders and discusses the relationship among these systems and selected demographic and clinical characteristics. Poor to fair agreement was generally demonstrated, except for Research Diagnostic Criteria (R. Spitzer et al, 1978) and Diagnostic and Statistical Manual of Mental Disorders-III—Revised (DSM-III—R), which demonstrated excellent agreement. Mostly, demographic and clinical variables (e.g., severity of depression) were unrelated to endogeneity diagnoses. The conclusion was reached that these criteria are not all measuring the same construct in older adults and that the relationship between depression severity and endogeneity should be discussed in terms of specific definitions rather than in general terms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Characteristics of face-centered cubic metals processed by equal-channel angular pressing

This review surveys the characteristics of face-centered cubic (fcc) metals and alloys processed by equal-channel angular pressing (ECAP). The significance of the Hall–Petch relationship for ultra-fine grained structures is examined and the dependence of the saturated stress obtained in ECAP on the absolute melting temperature is described and discussed. In addition, the flow processes at low temperatures in ultrafine-grained materials and the microstructural evolution of the dislocation densities and precipitates in some alloys of practical importance are also considered briefly.