Theory Summary and Future Directions

Summary talk at the Lepton-Photon Symposium, Cornell University, Aug. 10-15, 1993.Comment: (Talk presented at the Lepton-Photon Symposium, Cornell University, Aug. 10-15, 1993.) 19 page

Renesting Decisions and Annual Fecundity of Female Dickcissels (Spiza Americana) in Illinois

T.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in south- eastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ? 0.13 female fledglings per year. Of females that re- mained within the study area, 94% fledged young (1.25 ? 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved \u3e10 km) in 2.8 ? 0.6 days; others (36%) initiated subsequent nests in 8.5 ? 0.8 days. After fledging \u3e1 young, 95% of females ceased breeding for the season. Successful and failed nest sites were indistin- guishable on the basis of vegetative characteristics. Moreover, replacement nests had similar vegetative characteristics and were similar distances from habitat edges, compared with initial nests, which suggests that female Dickcissels do not or cannot improve nest-site characteris- tics in response to nest failure. We observed two behaviors unusual in female Dickcissels: one bird that fledged two broods in one season, and the return of five females banded in 1999 to the study site in 2000

Renesting Decisions and Annual Fecundity of Female Dickcissels (Spiza Americana) in Illinois

T.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in south- eastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ? 0.13 female fledglings per year. Of females that re- mained within the study area, 94% fledged young (1.25 ? 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved \u3e10 km) in 2.8 ? 0.6 days; others (36%) initiated subsequent nests in 8.5 ? 0.8 days. After fledging \u3e1 young, 95% of females ceased breeding for the season. Successful and failed nest sites were indistin- guishable on the basis of vegetative characteristics. Moreover, replacement nests had similar vegetative characteristics and were similar distances from habitat edges, compared with initial nests, which suggests that female Dickcissels do not or cannot improve nest-site characteris- tics in response to nest failure. We observed two behaviors unusual in female Dickcissels: one bird that fledged two broods in one season, and the return of five females banded in 1999 to the study site in 2000

Geochemistry of and alteration phases in martian lherzolite Y-793605

We have done preliminary SEM characterization of alteration phases on an exterior and an interior chip of martian lherzolite Yamato-793605,and have performed instrumental and radiochemical neutron activation analyses of a glass-poor and a glass-rich interior sample of the rock for a suite of 31 major and trace elements. To date, we have identified silica (containing minor amounts of S, K, Fe, Al), K-Fe-sulfate (probably jarosite) and Fe-phosphate as alteration phases in Y-793605. Of these, the silica and K-Fe-sulfate are likely terrestrial weathering products. Other evidence of alteration consists of what appear to be partly decomposed Ca-phosphate grains, which were probably originally igneous grains. No carbonates or Ca-sulfates have been identified as yet, and none of the alteration phases we have identified are unambiguously of martian origin. Compositionally, Y-793605 is very similar to the other two martian lherzolites ALHA77005 and LEW 88516. Our sample of Y-793605 is lower in the incompatible lithophile trace elements, such as the REE, than the average of either ALHA77005 or LEW 88516,but is within the ranges of individual analyses for ALHA77005. Y-793605 is a partial cumulate like the other lherzolites, but our sample contained less of a trapped melt component

Renesting Decisions and Annual Fecundity of Female Dickcissels (Spiza americana) in Illinois

ABSTRACT.-Renesting decisions and annual fecundity are crucial for interpreting other demographic information, yet are infrequently reported. We used radiotelemetry to monitor female Dickcissels (Spiza americana) throughout the 1999 and 2000 breeding seasons in southeastern Illinois. Overall fecundity (regardless of whether females remained in the study area throughout the breeding season) was 0.61 ± 0.13 female fledglings per year. Of females that remained within the study area, 94% fledged young (1.25 ± 0.15 female fledglings per year). Most females (62%) that experienced nest failure emigrated from the study area (moved \u3e10 km) in 2.8 ± 0.6 days; others (36%) initiated subsequent nests in 8.5 ± 0.8 days. After fledging ~1 young, 95% of females ceased breeding for the season. Successful and failed nest sites were indistinguishable on the basis of vegetative characteristics. Moreover, replacement nests had similar vegetative characteristics and were similar distances from habitat edges, compared with initial nests, which suggests that female Dickcissels do not or cannot improve nest-site characteristics in response to nest failure. We observed two behaviors unusual in female Dickcissels: one bird that fledged two broods in one season, and the return of five females banded in 1999 to the study site in 2000

A negative mass theorem for surfaces of positive genus

We define the "sum of squares of the wavelengths" of a Riemannian surface (M,g) to be the regularized trace of the inverse of the Laplacian. We normalize by scaling and adding a constant, to obtain a "mass", which is scale invariant and vanishes at the round sphere. This is an anlaog for closed surfaces of the ADM mass from general relativity. We show that if M has positive genus then on each conformal class, the mass attains a negative minimum. For the minimizing metric, there is a sharp logarithmic Hardy-Littlewood-Sobolev inequality and a Moser-Trudinger-Onofri type inequality.Comment: 8 page

The shape and erosion of pebbles

The shapes of flat pebbles may be characterized in terms of the statistical distribution of curvatures measured along their contours. We illustrate this new method for clay pebbles eroded in a controlled laboratory apparatus, and also for naturally-occurring rip-up clasts formed and eroded in the Mont St.-Michel bay. We find that the curvature distribution allows finer discrimination than traditional measures of aspect ratios. Furthermore, it connects to the microscopic action of erosion processes that are typically faster at protruding regions of high curvature. We discuss in detail how the curvature may be reliable deduced from digital photographs.Comment: 10 pages, 11 figure

Sustained replication of synthetic canine distemper virus defective genomes in vitro and in vivo

Defective interfering (DI) genomes have long been considered inconvenient artifacts that suppressed viral replication in vitr