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131.
An abundance index for 0+ Atlantic salmon was based on semi-quantitative electrofishing estimates at 137 sites in typical juvenile habitat throughout the River Bush (N. Ireland). 0 + abundance was linearly related to total smolt numbers migrating through a downstream trap in subsequent years ( r 2 = 0.716, P <0.001), suggesting a high degree of predictive ability. This predictive ability decreased as smolt age increased, suggesting influence of density-independent mortality. Potential application of the technique to estimate smolt production from rivers having no trapping facilities is discussed, together with sources of variability potentially affecting estimates. 相似文献
132.
Helen Kennedy 《Brittonia》1995,47(2):156-159
Calathea maasiorum from French Guiana and Surinam is described as new. It belongs toCalathea sectionBreviscapus Bentham. The foliage is patterned with a light green band along the midrib above. This new species has previously been confused
withC. cyclophora Baker from Amazonian Colombia, Brazil, Venezuela, and Guyana but it is distinguished fromC. cyclophora by the absence of bracteoles, the elliptic to obovate leaf blade, and shorter (1–2 cm long) bracts. 相似文献
133.
Dale J. Kennedy Douglas C. Montgomery Dwayne A. Rollier J. Bert Keats 《The International Journal of Life Cycle Assessment》1997,2(4):229-239
A methodology is presented to develop and analyze vectors of data quality attribute scores. Each data quality vector component represents the quality of the data element for a specific attribute (e.g., age of data). Several methods for aggregating the components of data quality vectors to derive one data quality indicator (DQI) that represents the total quality associated with the input data element are presented with illustrative examples. The methods are compared and it is proven that the measure of central tendency, or arithmetic average, of the data quality vector components as a percentage of the total quality range attainable is an equivalent measure for the aggregate DQI. In addition, the methodology is applied and compared to realworld LCA data pedigree matrices. Finally, a method for aggregating weighted data quality vector attributes is developed and an illustrative example is presented. This methodology provides LCA practitioners with an approach to increase the precision of input data uncertainty assessments by selecting any number of data quality attributes with which to score the LCA inventory model input data. The resultant vector of data quality attributes can then be analyzed to develop one aggregate DQI for each input data element for use in stochastic LCA modeling. 相似文献
134.
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136.
Robert K. Bright Michael H. Shearer Ronald C. Kennedy 《Cancer immunology, immunotherapy : CII》1995,40(3):206-211
Baculovirus-derived recombinant simian virus 40 (SV40) large tumor antigen (T-Ag) was used to immunize BALB/c mice to examine the lymphokines produced following immunization. Specifically, we examined production of interleukin-2 (IL-2), IL-4, IL-5 and interferon (IFN) from immune lymphocytes cultured with decreasing concentrations of recombinant SV40 T-Ag. We identified elevated levels of IFN and IL-2 by enzyme-linked immunosorbent assay and a murine CTLL-2 proliferation biossay respectively. We were unable to detect either IL-4 or IL-5. These data indicate the previously reported tumor immunity induced by recombinant SV40 T-Ag immunization most likely reflects a TH1-like immune response based on thein vitro production of both IFN and IL-2 by immune lymphocytes. 相似文献
137.
Wheat straw was pretreated with saturated lithium chloride in 4 m hydrochloric acid at 50°C for 1 h, then hydrolysed at 100°C for 1 min, to give 84% conversion to monosaccharides. Particle sizes, 150–355 mesh, were easily hydrolysed. Samples pretreated with saturated lithium chloride in 1 m hydrochloric acid at 27°C for 24 h were hydrolysed by Trichoderma viride cellulase (MVA 1284) [1,4-(1,3;1,4)-β-d-glucan 4-glucanohydrolase, EC 3.2.1.4] to give 20–23% monosaccharides for particle sizes of 150–250 mesh, and 82–95.4% for particle sizes of 250–355 mesh. 相似文献
138.
A mild and reproducible method has been developed for the surface-immobilization of enzymes on glutaraldehyde crosslinked gelatin beads. In this method glutaraldehyde is used in a dual capacity, as crosslinking agent and as the enzyme coupling agent. Glucoamylase (exo-α-1,4-d-glucosidase, EC 3.2.1.3), β-d-fructofuranosidase (invertase, EC 3.2.1.26) and β-d-glucoside (cellobiase, β-d-glucoside glucohydrolase, EC 3.2.1.21) have been successfully immobilized by this method, on the surface of the crosslinked gelatin particles. The method can be combined with the existing technology for the production of gelatin-entrapped enzymes. Thus, dual immobilized enzyme conjugates of glucoamylase and invertase have been prepared using this method, by entrapment of one enzyme in, and surface-binding of the other to, the gelatin matrix. The coupling of glucoamylase onto cross-linked gelatin particles by precipitation with poly(hexamethylenebiguanide hydrochloride) was also tested. 相似文献
139.
Cindy Lloyd John R. Kennedy Joseph Mendicino 《In vitro cellular & developmental biology. Plant》1984,20(5):416-432
Summary Swine tracheal epithelium has been cultured as explants in a chemically defined medium for periods of up to 2 wk. The viability
of the explants was shown by the preservation of the ultrastructural features of cells in the epithelial layer and by the
active incorporation of radioactive glucosamine and sulfate into secreted mucin glycoproteins. The rate of secretion of mucin
glycoprotein was about 0.035 mg per cm2 per d. After initial 24 h lag period was shown to be due to the equilibration of intracellular mucin glycoprotein pools with
radioactive precursors. The rate of secretion of glycoprotein showed a linear dependence on the area of the explant, and maximal
incorporation was observed at 200 μM glucosamine. A higher concentration of35SO4, 1000 μM, was required for maximal incorporation of the precursor. Insulin at 0.1 to 1 μg/ml increased the rate of secretion twofold,
whereas 0.1 to 100 μg/ml of hydrocortisone and 0.1 to 100 μg/ml of epinephrine significantly decreased the rate of secretion.
Vitamin A had little or no effect of normal trachea explants at low concentrations, and, at higher concentrations, 10−5
M, it decreased the secretion of mucin glycoproteins. Vitamin A, at a concentration of 10−9
M, increased the rate of synthesis of glycoprotein at least fourfold in trachea explants from vitamin A-deficient rats.
Mucus secretions collected from the surface of swine trachea and from the culture medium of trachea explants were purified.
The mucus was solubilized by reduction and carboxymethylation, and the high molecular weight mucin glycoproteins were purified
by chromatography on Sepharose CL-6B columns under dissociating conditions in 2M guanidine HCl. The mucin glycoproteins purified from swine trachea and from the culture medium of trachea explants were virtually
indistingushable. They showed the same properties when examined by gel electrophoresis and immunoprecipitation. The purified
glycoproteins contained about 25% protein, and serine, threonine, and proline were the principal amino acids present. More
than 80% of the carbohydride chains in both samples were released by treatment with alkaline borohydride. Nearly the same
molar ratio ofN-acetylgalactosamine,N-acetylglucosamine, galactose, fucose, sulfate, and sialic acid was found in both preparations.
This investigation was supported by U.S. Public Health Service Grants HL 20868, HL 24688, and HL 24718 from the National Heart,
Lung and Blood Institute, Bethesda, MD, and AM 28187 from the National Institute of Arthritis, Diabetes and Digestive and
Kidney Diseases, Bethesda, MD. 相似文献
140.
K A Kennedy J Chiment T Disotell D Meyers 《American journal of physical anthropology》1984,64(2):105-118
Principal-components analysis is used as an investigative procedure for establishing temporal, spatial and evolutionary-developmental changes in Homo sapiens skeletal specimens from prehistoric sites in South Asia. It is concluded that cranial variables which cluster hunter-gatherers within the sample are related to facial architecture with respect to robusticity and size. Older models presumably reflecting genetic affinities and racial classifications of prehistoric South Asians which were based upon univariate-bivariate statistical analyses are not supported by the results of this principal-components analysis. 相似文献