17,613 research outputs found
Chemical origin of the Venusian clouds Final report
Chemical analysis of cloud components in upper atmosphere of Venu
Chemical origin of the Venusian clouds Interim report, 1 Oct. 1966 - 30 Jan. 1967
Chemical reactions between solar hydrogen and carbon monoxide in Venus atmospher
Intersexual conflict influences female reproductive success in a female-dispersing primate
In group-living mammals, individual efforts to maximize reproductive success result in conflicts and compromises between the sexes. Females utilize counterstrategies to minimize the costs of sexual coercion by males, but few studies have examined the effect of such behaviors on female reproductive success. Secondary dispersal by females is rare among group-living mammals, but in western gorillas, it is believed to be a mate choice strategy to minimize infanticide risk and infant mortality. Previous research suggested that females choose males that are good protectors. However, how much female reproductive success varies depending on male competitive ability and whether female secondary dispersal leads to reproductive costs or benefits has not been examined. We used data on 100 females and 229 infants in 36 breeding groups from a 20-year long-term study of wild western lowland gorillas to investigate whether male tenure duration and female transfer rate had an effect on interbirth interval, female birth rates, and offspring mortality. We found that offspring mortality was higher near the end of malesā tenures, even after excluding potential infanticide when those males died, suggesting that females suffer a reproductive cost by being with males nearing the end of their tenures. Females experience a delay in breeding when they dispersed, having a notable effect on birth rates of surviving offspring per female if females transfer multiple times in their lives. This study exemplifies that female counterstrategies to mitigate the effects of male-male competition and sexual coercion may not be sufficient to overcome the negative consequences of male behavior
THE RELATIONSHIP BETWEEN MANAGERIAL HEURISTICS AND ECONOMICS IN PRICING RETAIL MEATS
This study develops a theoretical model of the multiproduct firm which allows for imperfect competition in the output market. Hypotheses are tested for retail meat prices concerning the degree and speed of price transmission, the effects of interfirm competition, and the interrelationship between prices within the store. Empirical results indicated that meat prices within a store were highly interrelated. Further, the firm was found to be very responsive to prices of competitors in the short run, but more responsive to wholesale price changes in the long run.Demand and Price Analysis,
Adventitious shoot propagation and cultural inputs in nursery production of a primocane-fruiting blackberry selection
Studies were conducted from January to October 2005 to determine the effect of root-cutting length on adventitious shoot yield and the management practices necessary to produce nurseryquality primocane-fruiting blackberry plants. The first portion of the study measured the average number of shoots produced from 7.6 cm- and 15.2 cm-long root cuttings of APF-44 blackberryāa primocane-fruiting genotype from the University of Arkansas breeding program. Cuttings were forced in a shallow bin containing a soilless potting medium. The average number of shoots per root cutting from 7.6 cm- and 15.2 cm- long root cuttings averaged 1.6 and 2.7 shoots per root cutting, respectively. Rooting percentage for collected shoots was nearly 100% regardless of root-cutting length source. A qualitative comparison of shoots from the two roots lengths was similar. The latter part of the study included various treatments on the rooted shoots that might affect the productivity and quality of the final product intended for nursery sales in early fall. With the aim of producing a flowering/fruiting shrub by late September, three treatments were applied: pot dimension, fertilizer rate, and shoot tipping. Fertilizer rate had the greatest impact of all treatments with the higher rate producing larger and more attractive plants. Above-normal summer/fall temperatures may explain lack of fruiting on APF-44 blackberries, but the dimension and size of some plants provided a portion of the intended aesthetic
Torsion and bending of nucleic acids studied by subnanosecond time-resolved fluorescence depolarization of intercalated dyes
Subnanosecond timeāresolved fluorescence depolarization has been used to monitor the reorientation of ethidium bromide intercalated in native DNA, synthetic polynucleotide complexes, and in supercoiled plasmid DNA. The fluorescence polarization anisotropy was successfully analyzed with an elastic model of DNA dynamics, including both torsion and bending, which yielded an accurate value for the torsional rigidity of the different DNA samples. The dependence of the torsional rigidity on the base sequence, helical structure, and tertiary structure was experimentally observed. The magnitude of the polyelectrolyte contribution to the torsional rigidity of DNA was measured over a wide range of ionic strength, and compared with polyelectrolyte theories for the persistence length. We also observed a rapid initial reorientation of the intercalated ethidium which had a much smaller amplitude in RNA than in DNA
Time-resolved spectroscopy of macromolecules: Effect of helical structure on the torsional dynamics of DNA and RNA
The torsional rigidity of DNA and RNA is measured via the fluorescence depolarization technique
Higher Derivative Corrections and Central Charges from Wrapped M5-branes
We compute four-derivative corrections to the AdS supergravity actions
arising from the near-horizon geometry of N M5-branes wrapped on either one or
two Riemann surfaces. This setup features the novel presence of both gauged
isometries as well as nontrivial hypermultiplets. We argue that the 5d
Chern-Simons terms receive not only higher-derivative corrections but also
contributions from Killing vector parameters, which we find must also be
corrected. We check the central charges found by our supergravity methods
against the dual field theory results and find perfect agreement at leading and
subleading order in N. Along the way, we find higher derivative corrections to
general AdS_5 and AdS_3x\Sigma_g geometries.Comment: 32 pages + 16 pages appendice
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