Assessing the influence of health on rural outmigration in Alaska

OBJECTIVES

This formative study is intended to generate questions and hypotheses regarding the relationship between health and outmigration from Alaska's rural communities. This study is the first to provide perspectives of rural Alaskans in the context of health concerns and health care delivery as determinants of outmigration.

STUDY DESIGN

The study collected secondary data through a comprehensive review of the literature and primary data through semi-structured interviews.

METHODS

The research design consisted of two iterative phases: a comprehensive review of published and gray literature relevant to rural health and migration in Alaska, and in-depth interviews with rural Alaskans who had recently moved from rural to urban settings. A total of 31 Alaskans aged 18+ from communities throughout the state were interviewed about the factors influencing their decision to move to an urban centre.

RESULTS

Three health-related determinants of outmigration from rural to urban Alaska emerged: (1) limited access to primary and specialized health care; (2) perceptions of health risks in rural communities; and (3) ripple effect migration of friends and family providing social support for rural Alaskans requiring health care. These determinants had disproportionate effects on young and female study participants.

CONCLUSIONS

We present data describing the growing influence of health concerns and health care delivery on outmigration in this underserved population, and conclude with recommendations for future avenues of research. Expanding the body of knowledge of the link between health and outmigration will provide rural Alaskans the opportunity to live and grow old in their own communities.

Computing texture boundaries from images

Recent computational and psychological theories of human texture vision assert that texture discrimination is based on first-order differences in geometric and luminance attributes of texture elements, called 'textons'. Significant differences in the density, orientation, size, or contrast of line segments or other small features in an image have been shown to cause immediate perception of texture boundaries. However, the psychological theories, which are based on the perception of synthetic images composed of lines and symbols, neglect two important issues. First, how can textons be computed from grey-level images of natural scenes? And second, how, exactly, can texture boundaries be found? Our analysis of these two issues has led to an algorithm that is fully implemented and which successfully detects boundaries in natural images. We propose that blobs computed by a centre-surround operator are useful as texture elements, and that a simple non-parametric statistic can be used to compare local distributions of blob attributes to locate texture boundaries. Although designed for natural images, our computation agrees with some psychophysical findings, in particular, those of Adelson and Bergen (described in the preceding article), which cast doubt on the hypothesis that line segment crossings or termination points are textons.

Compliance as a factor effecting the patency of a copolyurethane vascular graft

A new solid-wall vascular graft which has a compliance approximating that of the natural artery has been prepared from a copolyether-urethane material. Six of nine of these compliant grafts implanted in dogs were patent on removal, the longest implant time being 77 days for a 4-mm I.D. femoral artery graft. This is in contrast to noncompliant grafts of the same copolyurethane in which failure usually occurred within 48 hr.