VALIDATION OF A NOVEL TECHNIQUE FOR CREATING SIMULATED RADIOGRAPHS USING COMPUTED TOMOGRAPHY DATASETS

Understanding radiographic anatomy and the effects of varying patient and radiographic tube positioning on image quality can be a challenge for students. The purposes of this study were to develop and validate a novel technique for creating simulated radiographs using computed tomography (CT) datasets. A DICOM viewer (ORS Visual) plug‐in was developed with the ability to move and deform cuboidal volumetric CT datasets, and to produce images simulating the effects of tube‐patient‐detector distance and angulation. Computed tomographic datasets were acquired from two dogs, one cat, and one horse. Simulated radiographs of different body parts (n = 9) were produced using different angles to mimic conventional projections, before actual digital radiographs were obtained using the same projections. These studies (n = 18) were then submitted to 10 board‐certified radiologists who were asked to score visualization of anatomical landmarks, depiction of patient positioning, realism of distortion/magnification, and image quality. No significant differences between simulated and actual radiographs were found for anatomic structure visualization and patient positioning in the majority of body parts. For the assessment of radiographic realism, no significant differences were found between simulated and digital radiographs for canine pelvis, equine tarsus, and feline abdomen body parts. Overall, image quality and contrast resolution of simulated radiographs were considered satisfactory. Findings from the current study indicated that radiographs simulated using this new technique are comparable to actual digital radiographs. Further studies are needed to apply this technique in developing interactive tools for teaching radiographic anatomy and the effects of varying patient and tube positioning.     

Estimation of the Dietary Lipid Requirement Level of the White Crayfish Procambarus acutus acutus

Six isonitrogenous and isoenergetic diets containing graded levels of lipid (menhaden fish oil) were fed to juvenile white crayfish ( Procambarus acutus acutus ) over a 10 week period. A significant depression in weight gain was observed in crayfish fed diets containing 9% or more lipid. There were no significant differences in growth of crayfish fed diets containing 0 to 6% lipid. Whole-body percentages of lipid and dry matter decreased, and protein increased in crayfish fed high-lipid diets. Dietary lipid did not appear to influence survival or molting frequency. Whole-body lipids generally reflected dietary fatty acid composition.     

The influence of alternative plant propagation and stand establishment techniques on survival and growth of eastern cottonwood (Populus deltoides Bartr.) clones

Four eastern cottonwood clones, including standard operational clone ST66 and three advanced clonal selections were produced and included in a test utilizing five different plant propagation methods. Despite relatively large first-year growth differences among clones, all clones demonstrated similar responses to the treatments and clone × cutting treatment interactions were generally non-significant. The effects of changing cutting lengths are consistent with previous studies which indicated the potential for increased plant survival and growth with increased cutting lengths. Differences in stored carbohydrate reserves alone do not appear to completely control first-year growth and development of cuttings. First-year growth of 51 cm long cuttings planted 30.5 cm deep was greater than the same cuttings planted 48 cm deep. Stem form of plants derived from whip-tip propagation did not differ from plants derived from standard, unrooted cuttings. This propagation method offers the potential of far greater production capacity from a cutting orchard and rapid bulk-up of new or limited clones. Stand uniformity assessments suggest that surviving trees of each individual cutting treatment exhibit similar levels of growth variation. Optimization of plantation establishment techniques has the potential to increase growth of young Populus plantations.     

Realized gains from selection for spring wheat grain yield are different in conventional and organically managed systems

Breeding spring wheat (Triticum aestivum L.) specifically for organic production has been suggested by producers and researchers alike. To investigate the effects of management systems on selected spring wheat breeding line performance in multi-location tests in the northern Great Plains, we used a randomly derived population of 79 F6-derived recombinant inbred lines (RILs) from a cross between the Canadian hard red spring wheat cultivar AC Barrie and the CIMMYT derived cultivar Attila. The population, including the parents, was grown on conventionally and organically managed land in 12 environments over 3 years. Direct selection in each management system (10% selection intensity based on grain yield) resulted in three lines being retained in each management system, over the multi-location testing. Gains from 10% selection for grain yield in a ‘selection’ year were 3.4 times greater in conventional multi-site yield trials than in organically managed trials. Two lines (BA 05 and BA 36) ranked in the top 10% of both the conventional and organic selection trial of 2005, remained ranked 2nd and 1st, respectively, under conventional management in multi-site yield trials. However, these lines ranked 53rd and 21st, respectively, for grain yield in the multi-site organic yield trials. Selected lines were each yield stable within the management system in which they were selected. Following replicated multi-location yield trials, three lines from the population (BA 02, 29 and 58) ranked within the highest 10% yielding lines in both conventional and organic systems. The results of this study suggest that selection differences occur across multi-location tests, and that selection for grain yield in organic systems should be conducted within organic systems. It is evident, however, that data obtained from conventional yield trials also has some relevance towards breeding for organic environments.     

The extraction and partial purification of a rhamnosidase from Colorado potato beetle larvae (Leptinotarsa decemlineata (Say))

An enzyme which hydrolyzed a terminal rhamnose moiety from α-chaconine was extracted and partially purified from Colorado potato beetle (CPB) (Leptinotarsa decemlineata) larvae. This ammonium sulfate precipitated enzyme fraction resulted in nearly 97% metabolism of α-chaconine after a 144 hour incubation period at 42 C as determined by high performance liquid Chromatographic (HPLC) analysis. Approximately 81% of the metabolized α-chaconine was detected asβ ₂-chaconine. The isolated enzyme fraction from CPB larvae exhibited no metabolism of α-solanine. Metabolism was also followed over time by thin layer chromatography (tlc).     

New insights into high-molecular-weight glutenin subunits and sub-genomes of the perennial crop Thinopyrum intermedium (Triticeae)

Intermediate wheatgrass (Thinopyrum intermedium) is a perennial crop that possesses desirable agronomic traits and provides environmental services, e.g., reducing soil erosion, nitrate leaching and inputs of energy and pesticide. Thus, intermediate wheatgrass is currently being domesticated as a perennial grain crop. However, the genetic information for molecular breeding is quite limited. Here we report a molecular analysis of high-molecular-weight glutenin subunits (HMW-GS) in intermediate wheatgrass using gene cloning and protein biochemistry. Five HMW-GS genes were isolated from individual intermediate wheatgrass plants: two x-type genes TiHGS1 and TiHGS4, and three y-type genes TiHGS2, TiHGS3 and TiHGS5. Among them, TiHGS5 was novel and possessed an additional cysteine residue at the N-terminal domain or repetitive domain. Sequence alignments showed that TiHGS1 and TiHGS2 genes shared high identities (>96%) with the Glu-1Dx and Glu-1Dy genes, respectively, in common wheat and Aegilops species, TiHGS3 with HMW-GS genes from Dasypyrum or Pseudoroegneria, and TiHGS4 and TiHGS5 with HMW-GS genes from Thinopyrum elongatum. This work provides substantial new insights into the gene compositions and protein profiles of HMW-GS in intermediate wheatgrass, and also gives evidence about the genome components of intermediate wheatgrass.