The Crystal Structure of a Proposed Hinesol Intermediate

The structure of a proposed intermediate of the naturally occurring sesquiterpene hinesol was determined by X-ray analysis. The structure was solved using the heavy-atom technique and refined to an R index of 0-065 for 1739 non-zero reflections. The results of the analysis revealed that the intermediate had a structure incompatible with conversion to hinesol

The Crystal Structure of a Photodimer of 1,4-Epoxy-1,4-dihydronaphthalene

The crystal structure of a photodimer of l,4-epoxy-1,4-dihydronaphthalene, with empirical formula C_(20)H_(16)O_2, has been determined by the application of direct methods. Three-dimensional data were collected on a Datex-automated General Electric diffractometer to a minimum spacing of 1·0 Å. The coordinates of all atoms in the molecule, the isotropic temperature factors for the hydrogen atoms, and the anisotropic temperature factors for the other atoms were refined by the method of least squares. The final R index was 0·027. The crystals are orthorhombic, space group Pcɑ2_1 with ɑ = 16-52, b = 7·975 and c= 10·58 Å. Of four possible configurations, the molecule of the photodimer has the exotrans-exo configuration. Despite the lack of a center of symmetry in the space group, the molecule is centrosymmetric almost within experimental error

Elastic Correlations in Nucleosomal DNA Structure

The structure of DNA in the nucleosome core particle is studied using an elastic model that incorporates anisotropy in the bending energetics and twist-bend coupling. Using the experimentally determined structure of nucleosomal DNA [T.J. Richmond and C.A. Davey, Nature {\bf 423}, 145 (2003)], it is shown that elastic correlations exist between twist, roll, tilt, and stretching of DNA, as well as the distance between phosphate groups. The twist-bend coupling term is shown to be able to capture these correlations to a large extent, and a fit to the experimental data yields a new estimate of G=25 nm for the value of the twist-bend coupling constant

Enhancement of Rabi Splitting in a Microcavity with an Embedded Superlattice

We have observed a large coupling between the excitonic and photonic modes of an AlAs/AlGaAs microcavity filled with an 84-({\rm {\AA}})/20({\rm {\AA}}) GaAs/AlGaAs superlattice. Reflectivity measurements on the coupled cavity-superlattice system in the presence of a moderate electric field yielded a Rabi splitting of 9.5 meV at T = 238 K. This splitting is almost 50% larger than that found in comparable microcavities with quantum wells placed at the antinodes only. We explain the enhancement by the larger density of optical absorbers in the superlattice, combined with the quasi-two-dimensional binding energy of field-localized excitons.Comment: 5 pages, 4 figures, submitted to PR

A Preliminary Investigation of the Cr3Si-Mo Pseudo-Binary Phase Diagram

An investigation was undertaken to study the phase relations in Cr3Si alloyed with Mo varying from 10 to 83.5 wt. % of the material. Specimens were prepared from arc-melted buttons that were subsequently heat treated at 1673 K for 200 h and air quenched to room temperature to structures. Alloys containing more than 20 wt. % MO were primarily two-phase materials of M3Si and M5Si3, where M is (Cr,Mo). Three alloys contained less than 5% of a third phase, which also had the M5Si3 crystal structure. Differential thermal analysis (DTA) was performed on several specimens at temperatures up to 2073 K in order to determine a solidus curve for the M3Si phase. Since only one DTA peak was observed in each alloy, the M5Si3 phase must melt above 2073 K, the maximum temperature examined. A preliminary pseudo-binary phase diagram for (Cr,Mo)3Si and a portion of the 1673 K isothermal section of the Cr-Mo-Si ternary phase diagram are presented

The Crystal Structure of a Proposed Hinesol Intermediate

The structure of a proposed intermediate of the naturally occurring sesquiterpene hinesol was determined by X-ray analysis. The structure was solved using the heavy-atom technique and refined to an R index of 0-065 for 1739 non-zero reflections. The results of the analysis revealed that the intermediate had a structure incompatible with conversion to hinesol

SIMULATION OF BREED AND CROSSBREEDING EFFECTS ON COSTS OF PORK PRODUCTION

A bio-economic model of swine production was used to simulate expected performance effects of breeds in alternative breeding systems on total costs/100 kg of live weight (EWW) or/l00 kg lean (ELW) for marketing at 100 kg live weight and on costs/100 kg lean for marketing at mean 185-d weight (ELA). Effects of heterosis and of six U.S. breeds were simulated for integrated industry purebred (P), two-breed specific (2S), backcross (2B) and rotation cross (2R), and three-breed specific (3S) and rotation cross (3R) breeding systems. Traits considered were age at puberty (-PUB), conception rate (CR), litter size born alive (NBA), preweaning viability (VIAB), milk production (MILK), age at 100 kg live weight (-DAYS) and empty body fat percentage (-FAT). Cost reductions from crossbreeding systems were greater for ELA than for ELW or EWW, ranging from -3 to -5% for 2S, -6 to -7% for 2B and 2R, and -7 to -9% for 3S and 3R. Reductions in nonfeed costs were much greater than those in feed costs for EWW and ELW (-4 to -12% vs -2 to -4%), and especially for ELA (-9 to -17% vs -1 to -2%). Order of maternal trait importance in ranking breeds was NBA, VIAB, CR, MILK and -PUB for P, 2R and 3R systems and as maternal breeds in 2S and 3S systems. For cost of lean, -FAT was as important as NBA in all except maternal breed roles. For ELA, -DAYS was important in all breed roles, but not for EWW and ELW, especially in maternal breed roles. In ranking paternal breeds for use in 2S and 3S systems, the important traits were only VIAB for EWW, VIAB and -FAT for ELW, but VIAB,-FAT and -DAYS for ELA. Existing breeds ranked differently as paternal breeds than as maternal or general purpose breeds. Complementary paternal-maternal effects permitted greater cost reductions from best 3S (-7 to -10%) than from best 3R (-6 to -8%) breed combinations. Maternal breeds in crosses benefited from superiority in components of both sow and pig performance

Reproductive development and performance of inbred and crossbred boars

This report includes much of the material presented by the senior author as a doctoral dissertation--P. [3].Digitized 2007 AES.Includes bibliographical references (page 56)