Dislocation multiplication in bcc molybdenum: A dislocation dynamics simulation

Plastic deformation of Mo single crystals is examined by direct simulation of dislocation dynamics under stress. Initial dislocation populations are made to mimic real dislocation microstructures observed in transmission electron microscopy cross-sections of pure annealed Mo single crystals. No a priori sources for dislocation multiplication are introduced, and yet multiplication takes place through a sequence involving aggregation of grown-in superjogs, bowing of screw dislocation segments and fast lateral motion of edge segments, producing a large number of elongated loops and a characteristic cross-grid pattern of screw dislocations.     

Predictors of quality of life of Portuguese Americans: identity,acculturation, and religiosity

ABSTRACT

Utilising the Multicultural Assessment-Intervention Process (MAIP) framework, the present study examined the effects of acculturation, ethnic identity, and religiosity on Portuguese Americans’ perceptions of their quality of life. Several culturally-sensitive variables were used to predict quality of life attitudes among a convenience sample of 305 Portuguese American adults. A structural model with quality of life as the outcome variable, Portuguese identity as the predictor, and Anglo orientation and religious faith as separate mediators was tested and a simple mediation structure involving religious faith was confirmed. While Portuguese identity predicts quality of life directly, when religious faith was added into the model as a mediator, much of the predictive value of Portuguese identity on quality of life was funnelled through religious faith. Implications for future Portuguese American research were discussed.     

Cortisol and dehydroepiandosterone sulfate plasma levels and their relationship to aging,cognitive function,and dementia

We have studied the relationship between dehydroepiandrosterone sulfate (DHEAS), cortisol, and cognitive function in a population of demented patients (n=29), age-matched controls (n=46), and younger subjects (n=11). All were submitted to morning collection of blood for determination of plasma cortisol and DHEAS measured by 125I radioimmunoassay. DHEAS levels and cortisol/DHEAS ratios were significantly different among groups with higher DHEAS levels and lower cortisol/DHEAS ratios in younger people (Bonferroni p<.05). Cortisol levels were associated to the presence of dementia (Odds ratio=.93; 95% CI,.86-1.01). There was no difference between DHEAS levels of demented and age-matched controls; however, demented patients showed a trend for higher cortisol/DHEAS ratios than age-matched controls and the latter showed higher ratio values than younger subjects. DHEAS and cortisol plasma values were significantly correlated in all individuals (p<.01). In this study cortisol was independently associated to the presence of dementia.     

Estimating one's own and one's relatives' multiple intelligence: a study from Argentina

Participants from Argentina (N = 217) estimated their own, their partner's, their parents' and their grandparents' overall and multiple intelligences. The Argentinean data showed that men gave higher overall estimates than women (M = 110.4 vs. 105.1) as well as higher estimates on mathematical and spatial intelligence. Participants thought themselves slightly less bright than their fathers (2 IQ points) but brighter than their mothers (6 points), their grandfathers (8 points), but especially their grandmothers (11 points). Regressions showed that participants thought verbal and mathematical IQ to be the best predictors of overall IQ. Results were broadly in agreement with other studies in the area. A comparison was also made with British data using the same questionnaire. British participants tended to give significantly higher self-estimates than for relatives, though the pattern was generally similar. Results are discussed in terms of the studies in the field.     

Undernutrition during suckling and latent learning ability of rehabilitated adult male rats

The present report investigates the effects of early undernutrition on the latent learning ability of rehabilitated adult male rats in a simple maze task. Rats were undernourished during suckling by feeding their dams an 8% casein diet. Well-nourished dams received a 25% casein diet during the same period. Rats were weaned at 21 days of age and nutritionally rehabilitated until they became adults, when behavioral task was conducted. Under a nonappetitive condition, rats were exposed either to an open field or to a maze apparatus. They were thereafter deprived of water and tested in the maze apparatus. Both well-nourished and undernourished rats that had been previously exposed to the maze performed better than those exposed to the open field. Nutritional treatment had no effect on performance of either the latent learning or of the open-field groups. These results suggest that rehabilitated adult rats are able to learn about the environment when no immediate reinforcement is involved. The discrepancy between our findings and results reported by others may be due to differences in task complexity and/or perhaps to the fact that nutritional rehabilitation also plays a role in reversing some of the deleterious effects of early undernutrition on learning ability of rats.     

Boundedness and legitimacy in public planning

This article has two objectives: (1) to map some of the structural limitations to scientific or rational public planning; and (2) to explore the implications of this for a reconceptualization of the legitimacy of public planning. It is argued that some of the limitations to planning are inherent to the planning process in the sense that they cannot be fully mitigated through the refinement of procedures. They come to represent sources of “basic boundedness” that have to be addressed through a radical reinterpretation of the policy process itself. He is currently engaged in a project on systems risks and insurance issues associated with nuclear disasters. The author is especially indebted to Professor Aant Elzinga and Merle Jacob at Gothenburg University for input on this article.     

A comparison of agricultural biotechnology research communities in the UK and brazil

Thirty-four biotechnology researchers of the Biotechnology and Biological Sciences Research Council (BBSRC), United Kingdom, and twenty-eight of the Brazilian Agriculture Research Enterprise (Embrapa), Brazil, were asked which factors are important for research; and the external influences in defining their research project objectives. The data show that: 1) eight of the eighteen selected factors that influenced their research have statistically significant differences when the perceptions of both research groups were compared; and, 2) both research groups do not perceive significant influences from external groups and organizations when defining research project objectives.     

Becoming Racially Literate About Data and Data-Literate About Race: Data Visualizations in the Classroom as a Site of Racial-Ideological Micro-Contestations

Data visualizations are now commonplace in the public media. The ability to interpret and create such visualizations, as a form of data literacy, is increasingly important for democratic participation. Yet, the cross-disciplinary knowledge and skills needed to produce and use data visualizations and to develop data literacy are not fluidly integrated into traditional K–12 subject areas. In this article, we nuance and complicate the push for data literacy in STEM reform efforts targeting youth of color. We explore a curricular reform project that integrated explicit attention to issues pertaining to the collection, analysis, interpretation, representation, visualization, and communication of data in an introductory computer science class. While the study of data in this unit emphasized viewing and approaching data in context, neither the teacher nor the students were supported in negotiating the racialized context of data that emerged in classroom discussions. To better understand these dynamics, we detail the construct of racial literacy and develop an interpretative framework of racial-ideological micro-contestations. Through an in-depth analysis of a classroom interaction using this framework, we explore how contestations about race can emerge when data visualizations from the public media are incorporated into STEM learning precisely because the contexts of data are often racialized. We argue that access to learning about data visualization, without a deep interrogation of race and power, can be counterproductive and that efforts to develop authentic data literacy require the concomitant development of racial literacy.