A study of model deflection measurement techniques applicable within the national transonic facility

Moire contouring, scanning interferometry, and holographic contouring were examined to determine their practicality and potential to meet performance requirements for a model deflection sensor. The system envisioned is to be nonintrusive, and is to be capable of mapping or contouring the surface of a 1-meter by 1-meter model with a resolution of 50 to 100 points. The available literature was surveyed, and computations and analyses were performed to establish specific performance requirements, as well as the capabilities and limitations of such a sensor within the geometry of the NTF section test section. Of the three systems examined, holographic contouring offers the most promise. Unlike Moire, it is not hampered by limited contour spacing and extraneous fringes. Its transverse resolution can far exceed the limited point sampling resolution of scanning heterodyne interferometry. The availability of the ruby laser as a high power, pulsed, multiple wavelength source makes such a system feasible within the NTF

Christ at work : reflections on market economics and the mission of God

https://place.asburyseminary.edu/ecommonsatsdissertations/2501/thumbnail.jp

Groundwater Cleanup: Is It Worth It?

5 pages. Contains references

Groundwater Cleanup: Is It Worth It?

5 pages. Contains references

Melt-growth dynamics in CdTe crystals

We use a new, quantum-mechanics-based bond-order potential (BOP) to reveal melt-growth dynamics and fine-scale defect formation mechanisms in CdTe crystals. Previous molecular dynamics simulations of semiconductors have shown qualitatively incorrect behavior due to the lack of an interatomic potential capable of predicting both crystalline growth and property trends of many transitional structures encountered during the melt $\rightarrow$ crystal transformation. Here we demonstrate successful molecular dynamics simulations of melt-growth in CdTe using a BOP that significantly improves over other potentials on property trends of different phases. Our simulations result in a detailed understanding of defect formation during the melt-growth process. Equally important, we show that the new BOP enables defect formation mechanisms to be studied at a scale level comparable to empirical molecular dynamics simulation methods with a fidelity level approaching quantum-mechanical method

Reflections on Tiles (in Self-Assembly)

We define the Reflexive Tile Assembly Model (RTAM), which is obtained from the abstract Tile Assembly Model (aTAM) by allowing tiles to reflect across their horizontal and/or vertical axes. We show that the class of directed temperature-1 RTAM systems is not computationally universal, which is conjectured but unproven for the aTAM, and like the aTAM, the RTAM is computationally universal at temperature 2. We then show that at temperature 1, when starting from a single tile seed, the RTAM is capable of assembling n x n squares for n odd using only n tile types, but incapable of assembling n x n squares for n even. Moreover, we show that n is a lower bound on the number of tile types needed to assemble n x n squares for n odd in the temperature-1 RTAM. The conjectured lower bound for temperature-1 aTAM systems is 2n-1. Finally, we give preliminary results toward the classification of which finite connected shapes in Z^2 can be assembled (strictly or weakly) by a singly seeded (i.e. seed of size 1) RTAM system, including a complete classification of which finite connected shapes be strictly assembled by a "mismatch-free" singly seeded RTAM system.Comment: New results which classify the types of shapes which can self-assemble in the RTAM have been adde

Peripheral Blood Mononuclear Cell Cytokine and Proliferative Response to In Vitro Echinacea Stimulaton in Male College Wrestlers andSoccer Players During Preseason Practice

Advisor: David S. SenchinaThe effects of dietary botanical supplements on the immune response in athletes are unknown, despite a recent increase in herbal supplement use by both college and professional athletes. We conducted 2 separate studies to examine the effects of in vitro Echinacea stimulation on the immune responses of peripheral blood mononuclear cells (PBMCs) taken from athletes during preseason training. College-level male competitive athletes from 2 sports (wrestling and soccer) participated in the studies. PBMCs were isolated from blood sampled either pre- or post-practice, standardized to the same concentration, and then stimulated with extracts from Echinacea pallida, Echinacea simulata, or solvent vehicle control. Cytokine production (TNF, IL-Ib, IL-I0, and IFN-g) was measured from super-natants collected between 24-72 hrs contingent on the specific cytokine; proliferation was assessed at 72 hrs. Extracts were phytochemically profiled by high pressure liquid chromatography to quantify known bioactive compounds including alkamides and caffeic acid derivatives. Results differed between the wrestlers and soccer players. In general, E. simulata was a more potent immunomodulator than E. pallida in both studies. Following exercise, PBMC production of TNF, IL-l0, and IFN-g production either decreased or was unaffected. IL-lb levels showed no change in either study. PBMC proliferation increased in the wrestlers as a result of training, but decreased in the soccer players. In conclusion, observed effects were contingent on species chosen, time point within preseason training, and sport (training type).Drake University, College of Pharmacy and Health Sciences, Department of Biolog

The Effect of Micro-Gravity on in vitro Calcification

The experiment focuses on mineral deposition or calcification of cartilage. The experiments were used to compare the mineral formed in the microgravity of space with that formed on earth. Results of these experiments were anticipated to provide direct insight into how calcification in cartridge and bone may be controlled in space. In the C-2 experiment (STS 66), we found that mineralization started later in the cartridges (both on the ground and in hypo-gravity) than in plastic, and that mineralization appeared to be retarded in hypo-gravity. The flight experiments also showed that the cells differentiated normally, but more slowly than the ground controls, and that the matrix produced was not different from that made on the ground. The purpose of the C-5 experiment was to confirm these findings. The C-5 experiment was flown on STS-72. Because of a computer problem, cells received no gases and no nutrition. The C-7 was flown on STS-77. Ground controls were repeated a week later, however, because there was a problem with the temperature control during the flight, the concurrent ground controls were performed at a different temperature. Despite these problems, the results of the C-2 experiment were confirmed. The cells in the flight cultures did not mature, formed few cartilage nodules, and showed no evidence of mineral deposition up to a culture age of 28 days. Ground controls showed the presence of mineral (based on chemical, spectroscopic, and histochemical analyses) by 21 days. The mineral in these cultures was analogous to that found in calcifying cartilage of young chicks