Liquid metal magnetohydrodynamics (LMMHD) technology transfer feasibility study. Volume 1: Summary

The potential application of liquid metal magnetohydrodynamics (LMMHD) to central station utility power generation through the period to 1990 is examined. Included are: (1) a description of LMMHD and a review of its development status, (2) LMMHD preliminary design for application to central station utility power generation, (3) evaluation of LMMHD in comparison with conventional and other advanced power generation systems and (4) a technology development plan. One of the major conclusions found is that the most economic and technically feasible application of LMMHD is a topping cycle to a steam plant, taking advantage of high temperatures available but not usable by the steam cycle

Liquid metal magnetohydrodynamics (LMMHD) technology transfer feasibility study. Volume 2: Appendixes

For abstract, see N74-13466

Solution to the problem of the poor cyclic fatigue resistance of bulk metallic glasses

The recent development of metallic glass-matrix composites represents a particular milestone in engineering materials for structural applications owing to their remarkable combination of strength and toughness. However, metallic glasses are highly susceptible to cyclic fatigue damage, and previous attempts to solve this problem have been largely disappointing. Here, we propose and demonstrate a microstructural design strategy to overcome this limitation by matching the microstructural length scales (of the second phase) to mechanical crack-length scales. Specifically, semisolid processing is used to optimize the volume fraction, morphology, and size of second-phase dendrites to confine any initial deformation (shear banding) to the glassy regions separating dendrite arms having length scales of ≈2 μm, i.e., to less than the critical crack size for failure. Confinement of the damage to such interdendritic regions results in enhancement of fatigue lifetimes and increases the fatigue limit by an order of magnitude, making these “designed” composites as resistant to fatigue damage as high-strength steels and aluminum alloys. These design strategies can be universally applied to any other metallic glass systems

Progress Report: Centralized Ultrasound Processing

In January of 1998 Iowa State University began a twoyear cooperative research pilot project with the American Angus Association (AAA). The purpose was to organize the collection and interpretation of ultrasound images and calculate Expected Progeny Differences (EPDs) for genetic improvement of carcass traits using the ultrasound data. The first Centralized Ultrasound Processing (CUP) center was established and located at Iowa State Universtiy. In 1998 a select group of ultrasound technicians was trained following a unique protocol for the collection of ultrasound images including rump fat thickness, rib fat thickness, ribeye area and % intramuscular fat (marbling). Images for over 9,000 head of bulls, steers, replacement heifers and feedlot heifers were received and processed through the CUP laboratory during 1998. Many of the results of these data can be found in ASL R1625

Comparison of Sire Carcass EPD Rankings Using Real-time Ultrasound Measures from Yearling Angus Bulls Versus Using Measures from Developing Angus Heifers

The purpose of this study was to compare how sires rank on EPD generated solely from yearling Angus bull measures against those generated solely from developing heifer measures. Ultrasound EPD from heifer progeny ultrasound measures are ranking the sires identically to the EPD from the bull progeny ultrasound measures. The heifer data complement the bull data, and breeders should be encouraged to scan all of their developing females at or around 390 days of age to improve the accuracy of carcass EPD based ultrasound measures

Carcass EPDs from Angus Heifer Real-time Ultrasound Scans

The objective of this research was to use developing Angus heifer real-time ultrasound records to estimate genetic parameters and calculate carcass EPD for external 12-13th rib fat (FAT), rump fat thickness (RFAT), ribeye area (REA), and % intramuscular fat (%IMF). Heritability estimates are all of a moderate level (\u3e .40) and are higher than the estimates determined previously with bull-only ultrasound data. Genetic correlations are generally of the same magnitude and same sign as previously reported with the bull-only ultrasound data. Angus breeders need to be alerted to the fact that developing heifers can be scanned to accurately predict carcass merit in steer-mate half-sibs. The results of this research indicate that the heifer data may be more accurate than the half-sib yearling bulls findings because the heritability estimates from the heifer data are higher than those estimated from the yearling bull data

Genetic Relationship between Live Animal Ultrasound Measures and Scrotal Circumference in Yearling Angus Bulls

The purpose of this study was to determining the relationship between 365-d yearling scrotal circumference, scanning weight, and component ultrasound measured compositional traits. The genetic correlations between scrotal circumference measured at 365-d of age and other live animal measures are low. Of these five genetic relationships, the highest correlation is with % intramuscular fat (IMF) at .13. However, this is a low genetic correlation. The positive sign of the scrotal circumference-% IMF genetic correlation is encouraging for breeders wanting to increase scrotal circumference and % IMF at the same time. Scrotal circumference in yearling Angus bulls is not strongly linked genetically with weight and compositional traits. Selection programs for either increased retail product (as measured by weight and ribeye area) or quality (as measured by % IMF) will not result in an antagonistic effect on scrotal circumference

Responsiveness of PROMIS® to change in chronic obstructive pulmonary disease.

BackgroundChronic obstructive pulmonary disease (COPD) is a progressive chronic disease characterized by airflow obstruction that leads to shortness of breath and substantial negative impacts on health-related quality of life (HRQL). The course of COPD includes periodic acute exacerbations that require changes in treatment and/or hospitalizations. This study was designed to examine the responsiveness of Patient-Reported Outcomes Measurement Information System® (PROMIS®) measures to changes associated with COPD exacerbation recovery.MethodsA longitudinal analysis using mixed-effects models was conducted of people who were enrolled while stable (n = 100) and those who experienced an acute exacerbation (n = 85). PROMIS (physical function, pain interference, pain behavior, fatigue, anxiety, depression, anger, social roles, discretionary social activities, Global Health, dyspnea severity and dyspnea functional limitations) and COPD-targeted HRQL measures were completed at baseline and at 12 weeks.ResultsWe administered PROMIS measures using computer adaptive testing (CAT), followed by administration of any remaining short form (SF) items that had not yet been administered by CAT. Examination of the difference between group differences from baseline to 12 weeks in the stable and exacerbation groups revealed that the exacerbation group changed (improved) significantly more than the stable group in anxiety (p < .001 to p < .01; f2 effect size [ES] = 0.023/0.021), fatigue (p < .0001; ES = 0.036/0.047) and social roles (p < .001 to p < .05; ES = 0.035/0.024). All effect sizes were small in magnitude and smaller than hypothesized. Depression was also statistically significant (p < .05, SF only) but the ES was trivial. For all other PROMIS domains, the differences were not significant and ES were trivial.ConclusionsThis longitudinal study provides some support for the validity of the PROMIS fatigue, anxiety, and social roles domains in COPD, but further evaluation of responsiveness is warranted