Drosophila pseudoobscura (Diptera: Drosophilidae) of the Great Basin IV: a release experiment at Bryce Canyon

Some populations of Drosophila pseudoobscura in the Great Basin have very little genetic variation for third chromosome inversion gene arrangements. These populations are essentially monomorphic for the Arrowhead gene arrangement. At Bryce Canyon, Utah, individuals with other gene arrangements (Standard, Pikes Peak, and Treeline) were released and their frequencies monitored. One generation after release, the released arrangements had increased in frequency from 0.7% to almost 10%. After overwintering, the arrangement frequencies were not statistically different from the prerelease samples. The samples did demonstrate a low-level retention of the released Pikes Peak arrangement. The decline in the released arrangements was probably the result of large population size at Bryce Canyon and the bottleneck effects of overwintering. The results do not seem consistent with a model of the released arrangements having a lowered fitness.     

Local to unity,long‐horizon forecasting thresholds for model selection in the AR(1)

This article introduces a novel framework for analysing long‐horizon forecasting of the near non‐stationary AR(1) model. Using the local to unity specification of the autoregressive parameter, I derive the asymptotic distributions of long‐horizon forecast errors both for the unrestricted AR(1), estimated using an ordinary least squares (OLS) regression, and for the random walk (RW). I then identify functions, relating local to unity ‘drift’ to forecast horizon, such that OLS and RW forecasts share the same expected square error. OLS forecasts are preferred on one side of these ‘forecasting thresholds’, while RW forecasts are preferred on the other. In addition to explaining the relative performance of forecasts from these two models, these thresholds prove useful in developing model selection criteria that help a forecaster reduce error. Copyright © 2004 John Wiley & Sons, Ltd.     

Biomimetic synthesis of cannabispiran

Summary Total synthesis of cannabispiran (1) was accomplished by a biomimetic-type cyclization of the bibenzyl2, using K₃Fe(CN)₆ or MoOCl₄.Acknowledgment. Supported in part by the Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi.     

Familial association in serum IgE levels.

The serum IgE levels measured by RIST correlated closely with those obtained by the single radioimmunodiffusion method. Values for husband and wife were closely related as were those between father and daughter but in contrast to previous observations no significant relationship existed between IgE levels for mother and son.     

Fe(II)-induced decomposition of epidioxides. A chemical model for prostaglandin E,prostacyclin and thromboxane biosynthesis

Summary A chemical model for biosynthesis of PGE, PGX and the thromboxanes from the prostaglandin endoperoxides is presented which is based on known reactions of other endoperoxides with the Fe(II)–Fe(III) redox system in vitro.Supported in part by USPH grant CA-13121 through the National Cancer Institute.     

Constituents ofCannabis sativa L. XXI: Estrogenic activity of a non-cannabinoid constituent

Summary A non-cannabinoid phenol (4,4,dihydroxy-5-methoxybibenzyl) increased uterine weight in prepubescent female rats, suggesting non-cannabinoids contribute to the estrogenic effects ofCannabis.Acknowledgments. This research was supported by Contract 271-78-3527 from the National Institute on Drug Abuse and by the Research Institute of Pharmaceutical Sciences, University of Mississippi. The authors are grateful to Karen S. Tomaszewski for technical assistance.