Autonomous optical navigation for lunar missions

Four measurement options for Orion autonomous optical lunar navigation are analyzed using linear covariance analysis methods. The measurements include a feature tracking camera measurement, star landmark elevation measurement, star horizon elevation measurement, and star occultation measurement. Based on trade studies performed, the star landmark measurement is superior to the star horizon measurement closer to the lunar surface, while the horizon sensor has better performance above an altitude of several thousand kilometers. The feature tracking camera performs comparably to the star landmark measurement. The star occultation camera is the worst performer throughout all trajectories due to the inability to include measurements continuously. However, its ability to take occultation measurements on the sunlit or eclipsed side of the Moon makes it a valuable aid to the crater-based measurements, which can only be taken over a sunlit surface

Autonomous Optical Lunar Navigation

The performance of optical autonomous navigation is investigated for low lunar orbits and for high elliptical lunar orbits. Various options for employing the camera measurements are presented and compared. Strategies for improving navigation performance are developed and applied to the Orion vehicle lunar missio

Effects of deep-bedded finishing system on market pig performance, composition and pork quality

The purpose of this study was to compare effects of finishing environment on growth performance, pork quality and lipid composition of pork. Environments compared were standard confinement (CON) and deep-bedded semi-outdoor systems. The deep-bedded method employed in the current study was the use of hoop structures. Hoops are large, tent-like shelters with cornstalks or straw for bedding. Gilts ranging in weight from 59 to 71 kg were randomly assigned to treatments of Hoop (n = 50) and CON (n = 18) environments. Gilts were fed a two-phase dietary sequence, ad libitum for 45 days. Six gilts per treatment were selected for carcass composition and quality evaluation. The experiment was replicated a total of five times. Pigs raised in the Hoop environment gained significantly less and required significantly more feed for growth than pigs raised in the CON environment. Carcasses from CON-finished pigs were significantly fatter at the 10th rib, which lowered carcass percentage fat-free lean(FFL) and they also had greater loin marbling scores compared with carcasses from Hoop-finished pigs (P \u3c 0.05). Significant replication effects were noted on beginning weight, live weight, carcass weight, percentage FFL, backfat, lipid content and adipose firmness. Carcasses from Hoop pigs had lower proportions of palmitic acid (P \u3c 0.05), and higher proportions of oleic and linoleic acid (P \u3c 0.05) in the inner layer of adipose tissue. The proportion of saturated fatty acid was lower, and that of mono- and poly-unsaturated fatty acid was higher in the inner layer of the adipose tissue of Hoop pigs. Variations in fatty acid composition and lipid deposition may have been caused by environmental temperature, since decreases in environmental temperature accompanied compositional variation of the adipose, leading to higher proportions of monounsaturated fatty acid and lower proportions of saturated and polyunsaturated fatty acid in adipose tissue, regardless of treatment. Volatile profile analysis revealed that adipose tissue of Hoop pigs had significantly higher amounts of 3-butanal and heptanal compared with CON pigs, which may be related to the amount of oleic and linoleic acids composing the adipose tissue. These data indicate finishing pigs in hoop structures allows for exposure to fluctuating temperatures, which may influence the growth of pigs, as well as fatty acid composition and firmness of pork products

Variable-temperature, variable-field magnetic circular dichroism spectroscopic study of NifEN-bound precursor and “FeMoco”

NifEN plays a key role in the biosynthesis of the iron–molybdenum cofactor (FeMoco) of nitrogenase. A scaffold protein that hosts the conversion of a FeMoco precursor to a mature cofactor, NifEN can assume three conformations during the process of FeMoco maturation. One, designated ΔnifB NifEN, contains only two permanent [Fe4S4]-like clusters. The second, designated NifENPrecursor, contains the permanent clusters and a precursor form of FeMoco. The third, designated NifEN“FeMoco”, contains the permanent [Fe4S4]-like clusters and a fully complemented, “FeMoco”-like structure. Here, we report a variable-temperature, variable-field magnetic circular dichroism spectroscopic investigation of the electronic structure of the metal clusters in the three forms of dithionite-reduced NifEN. Our data indicate that the permanent [Fe4S4]-like clusters are structurally and electronically conserved in all three NifEN species and exhibit spectral features of classic [Fe4S4]+ clusters; however, they are present in a mixed spin state with a small contribution from the S > ½ spin state. Our results also suggest that both the precursor and “FeMoco” have a conserved Fe/S electronic structure that is similar to the electronic structure of FeMoco in the MoFe protein, and that the “FeMoco” in NifEN“FeMoco” exists, predominantly, in an S = 3/2 spin state with spectral parameters identical to those of FeMoco in the MoFe protein. These observations provide strong support to the outcome of our previous EPR and X-ray absorption spectroscopy/extended X-ray absorption fine structure analysis of the three NifEN species while providing significant new insights into the unique electronic properties of the precursor and “FeMoco” in NifEN

Technology Transfer Using XRSIM as a Training Tool

In a collaboration between Cowley County Community College and Iowa State University, unique capabilities at the institutions are being combined to develop an NDE simulation teaching tool. The tool, based on XRSIM [1–4], will allow physically accurate radiographic inspections to be simulated using a computer aided design (CAD) model of a part. XRSIM was developed primarily as an industrial problem-solving tool; however, it has much to offer as a teaching tool. Cowley County Community College is leading the effort to develop the course material that will allow instructors to use XRSIM to teach students the fundamentals of radiography.</p

A case report of full recovery from severe cerebral edema secondary to acetaminophen-induced hepatotoxicity in a 13 year old girl

Abstract Background Acetaminophen is a common cause of acute liver failure in pediatrics. Cerebral edema is a significant complication of acute hepatic failure and is associated with increased mortality. Case presentation We present a case of a 13 -year old girl with severe cerebral edema secondary to acetaminophen toxicity and hepatic failure. Her poor neurological status precluded her from liver transplantation and withdrawal of life sustaining treatment was recommended. However, with supportive care, she remarkably made a full recovery. Conclusions This case highlights the difficulties surrounding prognostication in pediatric patients with cerebral edema from acute liver failure secondary to acetaminophen toxicity

Spectroscopic Properties and Molecular Structure of 1,3-Dimethyl-2-(Se, Se-dibromoseleno)-2(3H)-imidazolylidene

Oxidative addn. of Br to 1,3-dimethyl-2(3H)-imidazoleselone results in a compd. that can be viewed as a Se(II) bromide complex with a stabilized imidazolylidene ring as verified by x-ray crystallog. The structure consists of dimeric pairs contg. nearly linear Br-Se-Br units bonded through C to planar imidazolylidene rings at torsion angles of 91.4° for N1-C1-Se1-Br1 and 76.8° for N3-C6-Se2-Br4. Significant intermol. contacts between dimeric units are seen through short Se-Se [3.494(1) Å] and Se1-Br4 bridging [3.509(1) Å]. Soln. state Raman data show the characteristic peaks for a linear Br-Se-Br moiety with a strong polarized peak at 158 cm-1 and a weak shoulder at 181 cm-1 corresponding to the sym. and asym. Br-Se-Br stretching modes resp. In the absence of x-ray data, correlation of structure to vibrational data provides further support for structural speculations in other compds. with the linear SeBr2 grouping. . Crystal structure data for C5H8N2Br2Se are: cell parameters: space group P21/c, a 7.999(2), b 14.624(3), c 16.697(3) Å, β=95.41(2), Z = 8, dc = 2.288 g/cm3, unique reflections = 3783, R = 0.045

Effects of deep-bedded finishing system on market pig performance, composition and pork quality

The purpose of this study was to compare effects of finishing environment on growth performance, pork quality and lipid composition of pork. Environments compared were standard confinement (CON) and deep-bedded semi-outdoor systems. The deep-bedded method employed in the current study was the use of hoop structures. Hoops are large, tent-like shelters with cornstalks or straw for bedding. Gilts ranging in weight from 59 to 71 kg were randomly assigned to treatments of Hoop (n = 50) and CON (n = 18) environments. Gilts were fed a two-phase dietary sequence, ad libitum for 45 days. Six gilts per treatment were selected for carcass composition and quality evaluation. The experiment was replicated a total of five times. Pigs raised in the Hoop environment gained significantly less and required significantly more feed for growth than pigs raised in the CON environment. Carcasses from CON-finished pigs were significantly fatter at the 10th rib, which lowered carcass percentage fat-free lean(FFL) and they also had greater loin marbling scores compared with carcasses from Hoop-finished pigs (P P P This article is from Animal 2 (2008): 459–470, doi:10.1017/S1751731107001292.</p