Publications by authors named "Ming D"

Regenerative Life Support Systems (RLSS) will be required to regenerate air, water, and wastes, and to produce food for human consumption during long-duration missions to the Moon and Mars. It may be possible to supplement some of the materials needed for a lunar RLSS from resources on the Moon. Natural materials at the lunar surface may be used for a variety of lunar RLSS needs, including (i) soils or solid-support substrates for plant growth, (ii) sources for extraction of essential, plant-growth nutrients, (iii) substrates for microbial populations in the degradation of wastes, (iv) sources of O2 and H2, which may be used to manufacture water, (v) feed stock materials for the synthesis of useful minerals (e.

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Mixtures of zeolite and phosphate rock (PR) have the potential to provide slow-release fertilization of plants in synthetic soils by dissolution and ion-exchange reactions. This study was conducted to examine solubility and cation-exchange relationships in mixtures of PR and NH4- and K-saturated clinoptilolite (Cp). Batch-equilibration experiments were designed to investigate the effect of PR source, the proportion of exchangeable K and NH4, and the Cp to PR ratio on solution N, P, K, and Ca concentrations.

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We have characterized features of the site recognized by a double-stranded DNA endonuclease, I-SceII, encoded by intron 4 alpha of the yeast mitochondrial COX1 gene. We determined the effects of 36 point mutations on the cleavage efficiency of natural and synthetic substrates containing the Saccharomyces capensis I-SceII site. Most mutations of the 18-bp I-SceII recognition site are tolerated by the enzyme, and those mutant sites are cleaved between 42 and 100% as well as the wild-type substrate is.

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The serum concentration of erythropoietin in 79 cases with various blood diseases, uremia, chronic obstructive pulmonary disease etc was determined. At comparable degrees of anemia, patients with myelodysplastic syndrome and aplastic anemia had the highest levels of erythropoietin in our study. The high level of erythropoietin titer in patients with aplastic anemia should be taken as the nom for renal synthesis and release of this hormone.

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America's long-term commitment to a new Space Exploration Initiative has focused attention on the basic requirements for establishing a permanently manned lunar outpost and, ultimately, a martian one. High among these is the development of Regenerative Life Support Systems--with lunar agriculture an essential component--to provide a high level of self-sufficiency.

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