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Analyses of thermal processes in the glass melter and storage container are given for vitrification of defense waste. 相似文献
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MM Mashaly GP Birrenkott MM EL-Begearmi BC Wentworth 《Canadian Metallurgical Quarterly》1976,55(4):1226-1234
Progesterone and luteinizing hormone (LH) were measuured in the plasma of Large White turkey hens at frequent intervals during the ovulatory cycle and during the periods when ovulations did not occur. The hormones were quantitated at the beginning and the end of the reproductive season to follow the change in patterns and concentrations of these hormones. Radioimmunoassay procedures were used to assay both hormones. Both progesterone and LH reached a peak amount at about 8 to 2 hours before ovulation. At no time did the progesterone peak precede that of LH. On the other hand, the peak of progesterone was observed to last somewhat longer than the LH peak. Progesterone and LH concentrations demonstrated no peak during the non-ovulatory periods. The patterns of both hormones at the end of the reproductive season was about the same as at the beginning of the season, but with lower concentrations. 相似文献
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Variable temperature Hall effect measurements have been made down to 9–10K on p-type Hg1−xCdxTe grown by liquid phase epitaxy on both CdTe and sapphire substrates. Carrier freeze-out was usually observed throughout
the measured temperature range. For most samples, the hole mobility was well-behaved and exhibited a maximum at ˜ 35K. Values
of acceptor ionization energy EA and donor concentration ND were estimated from the data, using a model assuming significant compensation, which provided a good fit to the low temperature
data. In addition, values of ND were also estimated from an analysis of the low temperature mobility using the hole effective mass as a parameter to provide
reasonable agreement between the ND values calculated from the Hall coefficient and mobility data. The measured carrier concentration is a result of close compensation
between stoichiometric acceptors and donors, with ND usually in the low-1017 cm−3 range. Average values of EA for as-grown, undoped x = 0.32 layers on CdTe and sapphire substrates are 7.4 and 6.6 meV, respectively. An activation energy
of 0.84 meV was determined for a Cu-doped x = 0.32 layer that was annealed in Hg vapor to reduce the number of Hg vacancies.
The average EA for undoped Hg-annealed x = 0.22 layers on CdTe substrates is 2.35 meV. Layers with x = 0.32 grown on sapphire substrates
have average carrier concentrations of 2.92 (σ = 0.54) × 1016 cm−3, compared with 4.64 (θ = 1.26) × 1016 cm−3 for the same composition layers grown on CdTe substrates. 相似文献
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DA Starr BC Williams Z Li B Etemad-Moghadam RK Dawe ML Goldberg 《Canadian Metallurgical Quarterly》1997,138(6):1289-1301
Mutations in the essential Drosophila melanogaster gene zw10 disrupt chromosome segregation, producing chromosomes that lag at the metaphase plate during anaphase of mitosis and both meiotic divisions. Recent evidence suggests that the product of this gene, DmZW10, acts at the kinetochore as part of a tension-sensing checkpoint at anaphase onset. DmZW10 displays an intriguing cell cycle-dependent intracellular distribution, apparently moving from the centromere/kinetochore at prometaphase to kinetochore microtubules at metaphase, and back to the centromere/kinetochore at anaphase (Williams, B.C., M. Gatti, and M.L. Goldberg. 1996. J. Cell Biol. 134:1127-1140). We have identified ZW10-related proteins from widely diverse species with divergent centromere structures, including several Drosophilids, Caenorhabditis elegans, Arabidopsis thaliana, Mus musculus, and humans. Antibodies against the human ZW10 protein display a cell cycle-dependent staining pattern in HeLa cells strikingly similar to that previously observed for DmZW10 in dividing Drosophila cells. Injections of C. elegans ZW10 antisense RNA phenocopies important aspects of the mutant phenotype in Drosophila: these include a strong decrease in brood size, suggesting defects in meiosis or germline mitosis, a high percentage of lethality among the embryos that are produced, and the appearance of chromatin bridges at anaphase. These results indicate that at least some aspects of the functional role of the ZW10 protein in ensuring proper chromosome segregation are conserved across large evolutionary distances. 相似文献
58.
BC Kone 《Canadian Metallurgical Quarterly》1997,30(3):311-333
Nitric oxide (NO) is a labile radical gas that is widely acclaimed as one of the most important molecules in biology. Through covalent modifications of target proteins and redox reactions with oxygen and superoxide radical and transition metal prosthetic groups, NO plays a critical role in many vital biological processes, including the control of vascular tone, neurotransmission, ventilation, hormone secretion, inflammation, and immunity. Moreover, NO has been shown to influence a host of fundamental cellular functions, such as RNA synthesis, mitochondrial respiration, glycolysis, and iron metabolism. NO is formed from L-arginine by NO synthases (NOSs), a family of related enzymes encoded by separate unlinked genes. The different NOS isozymes exhibit disparate tissue and intrarenal distributions and are governed by unique regulatory mechanisms. In the kidney, NO participates in several vital processes, including the regulation of glomerular and medullary hemodynamics, the tubuloglomerular feedback response, renin release, and the extracellular fluid volume. While NO serves beneficial roles as a messenger and host defense molecule, excessive NO production can be cytotoxic, the result of NO's reaction with reactive oxygen and nitrogen species, leading to peroxynitrite anion formation, protein tyrosine nitration, and hydroxyl radical production. Indeed, NO may contribute to the evolution of several commonly encountered renal diseases, including immune-mediated glomerulonephritis, postischemic renal failure, radiocontrast nephropathy, obstructive nephropathy, and acute and chronic renal allograft rejection. Moreover, impaired NO production has been implicated in the pathogenesis of volume-dependent hypertension. This duality of NO's beneficial and detrimental effects has created extraordinary interest in this molecule and the need for a detailed understanding of NO biosynthesis. 相似文献
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