Study of aerodynamic technology for single-cruise engine V/STOL fighter/attack aircraft

A conceptual design analysis is performed on a single engine V/STOL supersonic fighter/attack concept powered by a series flow tandem fan propulsion system. Forward and aft mounted fans have independent flow paths for V/STOL operation and series flow in high speed flight. Mission, combat and V/STOL performance is calculated. Detailed aerodynamic estimates are made and aerodynamic uncertainties associated with the configuration and estimation methods identified. A wind tunnel research program is developed to resolve principal uncertainties and establish a data base for the baseline configuration and parametric variations

In vitro and in vivo studies of the trypanocidal properties of WRR-483 against Trypanosoma cruzi.

BackgroundCruzain, the major cysteine protease of Trypanosoma cruzi, is an essential enzyme for the parasite life cycle and has been validated as a viable target to treat Chagas' disease. As a proof-of-concept, K11777, a potent inhibitor of cruzain, was found to effectively eliminate T. cruzi infection and is currently a clinical candidate for treatment of Chagas' disease.Methodology/principal findingsWRR-483, an analog of K11777, was synthesized and evaluated as an inhibitor of cruzain and against T. cruzi proliferation in cell culture. This compound demonstrates good potency against cruzain with sensitivity to pH conditions and high efficacy in the cell culture assay. Furthermore, WRR-483 also eradicates parasite infection in a mouse model of acute Chagas' disease. To determine the atomic-level details of the inhibitor interacting with cruzain, a 1.5 A crystal structure of the protease in complex with WRR-483 was solved. The structure illustrates that WRR-483 binds covalently to the active site cysteine of the protease in a similar manner as other vinyl sulfone-based inhibitors. Details of the critical interactions within the specificity binding pocket are also reported.ConclusionsWe demonstrate that WRR-483 is an effective cysteine protease inhibitor with trypanocidal activity in cell culture and animal model with comparable efficacy to K11777. Crystallographic evidence confirms that the mode of action is by targeting the active site of cruzain. Taken together, these results suggest that WRR-483 has potential to be developed as a treatment for Chagas' disease

Maximizing DDGS for Finishing Pigs in Bedded Hoop Barns: Trial One

Iowa’s ethanol industry continues to expand rapidly. A major coproduct of ethanol production is dried distillers grains with solubles (DDGS). Higher prices for corn and increasing supplies of DDGS have generated questions about feeding DDGS to market swine. The objective of this study was to evaluate various programs to maximize DDGS feeding to finishing pigs in bedded hoop barns. The work reported is the first of several trials planned

Maximizing DDGS for Finishing Pigs in Bedded Hoop Barns

Higher prices for corn and increasing supplies of DDGS have generated questions about feeding DDGS to market swine. The objective of this study was to evaluate various programs to maximize DDGS feeding to finishing pigs in bedded hoop barns. The project was conducted during 2008 and 2009 at the ISU Western Research Farm, Castana, IA. The pens were in small hoop barns with two pens per barn. Each pen was assigned to one of three dietary treatments— continuous 20% DDGS (Cont), a step-up program from 0% to 30% DDGS (Step), and a high DDGS program that rapidly got pigs to 30% DDGS (High). All treatments were fed a 20% DDGS diet for the last phase of the trial. There were 4 dietary phases in the 98-day trial. Phase 1 and 4 were each 21d. Phase 2 and 3 were each 28d. The diets were pelletted and fed ad libitum. Within each phase, the diets were formulated to be equal in apparent digestible amino acids—lysine, threonine, and tryptophan. The pigs consumed the diets readily with no apparent problems making the transition among the diets. Feed intake (ADFI), growth (ADG), and feed per liveweight gain (F/G) did not differ among treatments (P \u3e 0.05). No major differences were noted in backfat thickness (BF) and loin muscle area (LMA) (P \u3e 0.05). Also, based on the means of fatty acid saturation, iodine values, and belly flop scores of selected pigs in trial (one, two or three), the differences in unsaturation percentages, iodine value and belly flop scores between treatments were minor. On average, a pig fed the continuous program consumed 119 lb of DDGS or 20% of the total feed over the 98-day feeding trial (from 54 to 274 lb). A pig fed the Step-up program consumed 106 lb of DDGS or 17% of the total feed. A pig fed the High program consumed 162 lb of DDGS or 26% of the total feed. This work suggests that diets and feeding programs can be designed to increase DDGS usage by market swine without negatively affecting pig performance. Also formulating diets on apparent digestible amino acid content may be advantageous when using DDGS on swine diets. The pelleted diets worked well with no problems in feed flow or fines separation

Feeding DDGS to Finishing Pigsin Deep-Bedded Hoop Barns

The ethanol industry in Iowa has rapidly expanded in the last several years. A major coproduct of ethanol production is dried distillers grains with solubles(DDGS). Higher prices for corn and ample supplies of DDGS has generated interest in feeding DDGS to finishing pigs. Challenges in feeding DDGS supplemented diets to finishing swine include problems of feed flowability in bulk bins and feeders, reduced feed intake, and softer, oilier fat in pork carcasses. Pelleted diets have improved flowability and may stimulate feed intake, but thus far no studies have examined feeding DDGS-supplemented dietsin pelletted form to pigs. The objective of this study was to evaluate pelletted DDGS-based diets fed to finishing pigs

Triticale—A Possible Third Crop for Iowa

Triticale (trit-ah-kay-lee) is a close relative of wheat that results from pollinating durum wheat with rye pollen, and then using that cross in a breeding program to produce stable, self-replicating varieties. Triticale yield, stress tolerance, and disease resistance are greater than that of wheat. Triticale doesn’t currently possess the grain traits of bread wheat, so its greatest marketing potential is as animal feed

A Sensitivity Study on the Effects of Particle Chemistry, Asphericity and Size on the Mass Extinction Efficiency of Mineral Dust in the Earth's Atmosphere: From the Near to Thermal IR

To determine a plausible range of mass extinction efficiencies (MEE) of terrestrial atmospheric dust from the near to thermal IR, sensitivity analyses are performed over an extended range of dust microphysical and chemistry perturbations. The IR values are subsequently compared to those in the near-IR, to evaluate spectral relationships in their optical properties. Synthesized size distributions consistent with measurements, model particle size, while composition is defined by the refractive indices of minerals routinely observed in dust, including the widely used OPAC/Hess parameterization. Single-scattering properties of representative dust particle shapes are calculated using the T-matrix, Discrete Dipole Approximation and Lorenz-Mie light-scattering codes. For the parameterizations examined, MEE ranges from nearly zero to 1.2 square meters per gram, with the higher values associated with non-spheres composed of quartz and gypsum. At near-IR wavelengths, MEE for non-spheres generally exceeds those for spheres, while in the thermal IR, shape-induced changes in MEE strongly depend on volume median diameter (VMD) and wavelength, particularly for MEE evaluated at the mineral resonant frequencies. MEE spectral distributions appear to follow particle geometry and are evidence for shape dependency in the optical properties. It is also shown that non-spheres best reproduce the positions of prominent absorption peaks found in silicates. Generally, angular particles exhibit wider and more symmetric MEE spectral distribution patterns from 8-10 micrometers than those with smooth surfaces, likely due to their edge-effects. Lastly, MEE ratios allow for inferring dust optical properties across the visible-IR spectrum. We conclude the MEE of dust aerosol are significant for the parameter space investigated, and are a key component for remote sensing applications and the study of direct aerosol radiative effects

Inhibitors of SARS-CoV entry--identification using an internally-controlled dual envelope pseudovirion assay.

Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) emerged as the causal agent of an endemic atypical pneumonia, infecting thousands of people worldwide. Although a number of promising potential vaccines and therapeutic agents for SARS-CoV have been described, no effective antiviral drug against SARS-CoV is currently available. The intricate, sequential nature of the viral entry process provides multiple valid targets for drug development. Here, we describe a rapid and safe cell-based high-throughput screening system, dual envelope pseudovirion (DEP) assay, for specifically screening inhibitors of viral entry. The assay system employs a novel dual envelope strategy, using lentiviral pseudovirions as targets whose entry is driven by the SARS-CoV Spike glycoprotein. A second, unrelated viral envelope is used as an internal control to reduce the number of false positives. As an example of the power of this assay a class of inhibitors is reported with the potential to inhibit SARS-CoV at two steps of the replication cycle, viral entry and particle assembly. This assay system can be easily adapted to screen entry inhibitors against other viruses with the careful selection of matching partner virus envelopes