17,950 research outputs found
Biodemography: Research prospects and directions
The purpose of this opinion report is to outline what I consider to be the most promising areas for future biodemographic research and to suggest ways in which the field can be moved forward. I discuss five major themes: i) biodemography of disability; ii) ecological, developmental, behavioral and evolutionary biodemography; iii) biodemography of sociality; iv) genomic and genetic biodemography; and v) biodemographic modeling and analysis. I consider the last two areas (genomics/genetics; modeling/analysis) as both stand-alone topics and cross-cutting concepts. At the end of the paper I present ideas for charting the future course including strengthening and expanding infrastructure, database and website development, organizing conferences, submitting new training grants, and integrating biodemography into teaching programs.biodemography, frailty, life span, longevity
A Partition Theorem for a Randomly Selected Large Population
We state and prove a proposition on partitioning of a randomly selected large
population into stationary and non-stationary populations by using a property
of stationary population identity. Applicability of this theorem for practical
purposes is summarized at the end.Comment: 7 pages, a new result in population dynamic
Progress toward a cosmic dust collection facility on space station
Scientific and programmatic progress toward the development of a cosmic dust collection facility (CDCF) for the proposed space station is documented. Topics addressed include: trajectory sensor concepts; trajectory accuracy and orbital evolution; CDCF pointing direction; development of capture devices; analytical techniques; programmatic progress; flight opportunities; and facility development
Prospects for an orbital determination and capture cell experiment
A dust experiment which combines measurements of the elemental and isotopic composition of individual particles with orbital information would contribute fundamental, new scientific information on the sources contributing to the micrometeoroid population. The general boundary conditions for such a system are: (1) it must be capable of measuring velocities in the range of 10 km/sec to 100 km/sec with several percent accuracy; (2) it must collect particles in such a way that the debris atoms are locally concentrated so that precise isotopic measurements are possible; (3) it should collect particles over a wide range of sizes starting with a lower limit of 10 microns; (4) it should incorporate materials that will not compromise the isotopic measurements; and (5) it should be large enough to obtain statistically meaningful results within a reasonable exposure time. Techniques which may satisfy these conditions are described
GreenCare for Children -- Measuring Environmental Hazards in the Childcare Industry
Presents findings from a two-year survey administered to a random sampling of childcare providers. Developed and interpreted by a diverse team of industry, technical, and educational experts
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