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Introduction 'Where is the BRC when we need it?' We have heard this question over the years from black activists from one side of the U.S. to another, but it [...]

A series of peroxyl radical clocks are developed and calibrated based on the competition between the unimolecular beta-fragmentation [k(sub beta)] of a peroxyl radical and bimolecular reaction with a hydrogen atom donor [k(sub H)]. Peroxyl radical clock methodology is applied to determine inhibition and propagation rate constants ranging from 10(super 0) to 10(super 7) M(super -1) s(super -1).

Autoxidants of cis,cis cis,trans and trans,trans nonconjugated octadecadienoates and pentadecadienes are carried out in the presence of Alpha-tocopherol to investigate the effect of olefin geometry on this oxidation process and find the factors influencing the autoxidation of fatty acids. The trans character of the diene increases, the amount of O(sub 2) trapping at the central (bis-allylic) position of the pentadienyl radical also increases.

We estimated annual apparent survival, recruitment, and rate of population growth of breeding Ruby-throated Hummingbirds (Archilochus colubris), while controlling for transients, by using 18 years of capture-mark-recapture data collected during 1984-2001 at Hilton Pond Center for Piedmont Natural History near York, South Carolina. Resident males had lower apparent survival (0.30 [+ or -] 0.05 SE) than females (0.43 30 [+ or -] 0.04). Estimates of apparent survival did not differ by age. Point estimates suggested that newly banded males were less likely than females to be residents, but standard errors of these estimates overlapped (males: 0.60 30 [+ or -] 0.14 SE; females: 0.67 30 [+ or -] 0.09). Estimated female recruitment was 0.60 30 [+ or -] 0.06 SE, meaning that 60% of adult females present in any given year had entered the population during the previous year. Our estimate for rate of change indicated the population of female hummingbirds was stable during the study period (1.04 30 [+ or -] 0.04 SE). We suggest an annual goal of [greater than or equal to] 64 adult females and [greater than or equal to] 64 immature females released per banding area to enable rigorous future tests for effects of covariates on population dynamics. Development of a broader cooperating network of hummingbird banders in eastern North America could allow tests for regional or meta-population dynamics in this species. Key words: Archilochus colubris, mark-recapture, population growth, recruitment, Ruby-throated Hummingbird, survival, transients.

Profile writers are concerned about hurting their subjects and many writers deal with such concerns by seeking willing subjects and explaining the consequences of a profile. Children are some of the most difficult ethical concerns in profile writing, and some authors use pseudonyms for the children. Journalists may often not be able to assess the potential damage a story may have.

The public and semi-public sectors of the economy have contributed greatly to the economic development of Sunbelt states and localities. Agriculture, energy and defense have been leading forces in Sunbelt development. Government assistance supported agricultural firms and federal tax expenditures provided the oil depletion allowance which benefited oil producers. The migration of manufacturing firms and the proliferation of high-tech industries in the region was a consequence of massive military investments.