Health Care Disparities Knowledge, Attitudes, and Behaviors in Resident Physicians.

PURPOSE: Health care disparities are an important but sometimes underrepresented topic in graduate medical education. In this study we measured the impact of educational and behavioral interventions on resident knowledge about and attitudes toward health care disparities. METHODS: Faculty from 6 residency programs designed and presented an hour-long educational intervention to emphasize the importance of and increase resident knowledge about health care disparities. Selected residents then helped design a month-long behavioral intervention to engage their peers in conversations about disparities with patients. Surveys were administered pre- and post-educational intervention as well as post-behavioral intervention in order to measure the impact each intervention had on resident knowledge and attitudes. RESULTS: Paired-samples t-tests showed that residents were more knowledgeable about health care disparities issues following didactic teaching (P<0.001) and felt such issues were more important (P<0.001). Furthermore, presence of these feelings significantly predicted the frequency of engaging in the behavioral intervention (r=0.44, P<0.01). CONCLUSIONS: Two brief, simple interventions produced significant changes in resident knowledge, attitudes and behaviors regarding health care disparities. The educational intervention was most effective at increasing knowledge of disparities in general and encouraging participation in the behavioral intervention, while the behavioral intervention was useful in increasing knowledge of specific patients' barriers to care.

Electronic selection rules controlling dislocation glide in bcc metals.

The validity of the structure-property relationships governing the low-temperature deformation behavior of many bcc metals was brought into question with recent ab initio density functional studies of isolated screw dislocations in Mo and Ta. These relationships were semiclassical in nature, having grown from atomistic investigations of the deformation properties of the group V and VI transition metals. We find that the correct form for these structure-property relationships is fully quantum mechanical, involving the coupling of electronic states with the strain field at the core of long a/<2111> screw dislocations.

Scale-free intermittent flow in crystal plasticity.

Under stress, crystals irreversibly deform through complex dislocation processes that intermittently change the microscopic material shape through isolated slip events. These underlying processes can be revealed in the statistics of the discrete changes. Through ultraprecise nanoscale measurements on nickel microcrystals, we directly determined the size of discrete slip events. The sizes ranged over nearly three orders of magnitude and exhibited a shock-and-aftershock, earthquake-like behavior over time. Analysis of the events reveals power-law scaling between the number of events and their magnitude, or scale-free flow. We show that dislocated crystals are a model system for studying scale-free behavior as observed in many macroscopic systems. In analogy to plate tectonics, smooth macroscopic-scale crystalline glide arises from the spatial and time averages of disruptive earthquake-like events at the nanometer scale.

Memory in time-dependent density functional theory.

Exact time-dependent density functionals remember both the entire history of the density and the initial wave function. We show that the two effects are intimately related, and all history dependence can be written as initial-state dependence, including that of the exchange-correlation kernel. For states that can be evolved from a ground state, all initial-state dependence is a dependence on a pseudo-prehistory, providing a route to excited-state densities from time-dependent density functional theory.