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911.
Analysis of wine components in Cynthiana and Syrah wines 总被引:2,自引:0,他引:2
Walker T Morris J Threlfall R Main G 《Journal of agricultural and food chemistry》2003,51(6):1543-1547
Red wine is composed of a complex matrix of compounds that can interfere with analysis. A high-performance liquid chromatography (HPLC) procedure was developed to efficiently analyze organic acids, sugars, glycerol, and ethanol in Cynthiana (Vitis aestivalis) wine. Standard laboratory procedures (pH, titratable acidity, and color attributes) and HPLC were found reproducible for Cynthiana wine. HPLC recovery efficiency was determined by analysis of spiked and unspiked samples (model, Cynthiana, and Syrah (Vitis vinifera) wines). Although recovery of components was greater in the model wine, recovery in Cynthiana and Syrah wine was comparable. The HPLC procedure was further compared to commercial rapid enzyme analysis tests using model, Cynthiana, and Syrah wines. HPLC analyses were more accurate than enzymatic tests for determining components in the model, Cynthiana, and Syrah wines. Considering the complexity of the wines analyzed, reproducibility and recovery of the HPLC procedure was demonstrated and showed improvement and precision when compared to existing methods. 相似文献
912.
M W Trucksess K Young K F Donahue D K Morris E Lewis 《Journal of the Association of Official Analytical Chemists》1990,73(3):425-428
Three different methods were compared for the determination of total flatoxins in corn and peanuts naturally contaminated with aflatoxins and in corn, peanuts, cottonseed, peanut butter, and poultry feed spiked with aflatoxins B1, B2, and G1. The 3 methods were an enzyme-linked immunosorbent assay (ELISA) screening test; a monoclonal antibody-affinity column-solid-phase separation method; and the AOAC official thin-layer chromatography (TLC) methods for all except poultry feed, for which Shannon's TLC method for mixed feed was used. The ELISA test is designed to provide only positive results for total aflatoxins at greater than or equal to 20 ng/g or negative results at less than 20 ng/g. The affinity column separation is coupled with either bromination solution fluorometry to estimate total aflatoxins or liquid chromatography (LC) to quantitate individual aflatoxins. Fluorodensitometry was used to determine aflatoxins in commodities analyzed by the TLC methods. The LC and TLC results were in good agreement for all the analyses. The results for the affinity column using bromination solution fluorometry were similar except those for cottonseed, which were about 60% higher. The ELISA screening method correctly identified naturally contaminated corn and peanut positive samples. No false positives were found for controls. The correct response for spiked corn, raw peanuts, peanut butter, and cottonseed at greater than or equal to 20 ng aflatoxins/g was about 90%. The correct response for spiked poultry feed at greater than or equal to 20 ng aflatoxins/g was about 50%. 相似文献
913.
We collected cobbles covered in biofilm from High Ore Creek, Montana, placed them in 12 transparent PVC plastic chambers, and exposed the chambers to four treatments: Sunlight, Sunlight-occluded, DCMU (photosynthesis inhibited), and Formalin. Total aqueous zinc (Zn) concentrations in the Sunlight treatment decreased during the 4-h experiment and were significantly lower (P?≤?0.05) than in the other three treatments, in which the total aqueous Zn concentrations did not decrease significantly. Therefore, we believe photosynthesis in the biofilm played a role in causing total aqueous Zn concentrations in the Sunlight treatment to decrease, and we believe a similar process contributes to diel Zn cycling in High Ore Creek and some other metals-contaminated streams. 相似文献
914.
David L. Morris Martin S. Ridout 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(2):158-169
Concentrations of microorganisms can be estimated from colony counts at different dilutions. However, complications can occur
because of colony overlap or inhibition of colony growth. We develop a model of inhibition in which colonies fail to develop
if spores are close to spores of other inhibitory species. The model has three parameters, but a limiting case of the model
with only two parameters is shown to be more useful in practice. This latter model, which is a generalized linear model, is
fitted to colony counts of the fungus Verticillium dahliae and contrasted with a model suggested in an earlier article. 相似文献
915.
Humic acids (HAs) isolated from five soils (Luvisols, with 460–600 mm rainfall, Nitosols and Ferralsol, with 1060–1950 mm rainfall) from different ecological regions of Kenya were characterized by 13C NMR and IR spectroscopy, elemental analyses and optical measurements. The data suggest that excessive rainfall in sub-humid regions may lower the molecular weights of the HAs as well as their aromaticities. Concentrations of aliphatic components, including aminoacids and carbohydrates, in the HAs from the sub-humid regions were higher (40–42 wt/wt %) than those in the HAs isolated from soils of the semi-arid regions (29–32 wt/wt %). Chemical characteristics of the soils from the sub-humid regions of Kenya resembled those of the HAs from temperate regions but differed from those of HAs originating from arid regions. Annual rainfall and vegetation appeared to affect the composition of HAs but effects of elevation and temperature were less clear. 相似文献
916.
Retrospective Study of Streptokinase Administration in 46 Cats with Arterial Thromboembolism 总被引:1,自引:1,他引:0
Kari E. Moore DVM Nancy Morris DVM Nishi Dhupa BVSc DACVECC DACVIM Robert J. Murtaugh DVM MS DACVECC DACVIM John E. Rush DVM MS DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2000,10(4):245-257
A retrospective evaluation was performed on 46 cats with arterial thromboembolism (ATE) that were treated with streptokinase (SK). Significant heart disease was diagnosed in 45/46 cats, and 21/46 cats had congestive heart failure. Variable dosing schemes of streptokinase were administered within 1–20 hours following the onset of clinical signs (median = 5.5 hours). There was no difference between survivors (S) and non-survivors (NS), based on time of administration of SK after onset of clinical signs. Twenty-five (54%) of the cats had return of pulses within 2–24 hours of treatment. Fourteen (30%) of the cats had return of motor function between 9 hours and 6 days. Fifteen of the cats (33%) were discharged from the hospital, 18 (39%) died in the hospital, and 13 (28%) cats were euthanized due to complications or poor response to treatment. Four of 5 cats (80%) with single limb dysfunction survived to hospital discharge. Life threatening hyperkalemia was diagnosed in 16 cats (35%) after SK administration. Hyperkalemia was more likely to occur with the longer duration of SK infusion. Eleven cats (24%) developed clinical signs of bleeding following SK administration and 3 of these cats required a blood transfusion. Laboratory testing documented coagulopathy following SK administration in 11 out of 17 cats tested. Hypothermia and azotemia prior to SK administration and the development of hyperkalemia were negatively associated with survival. 相似文献
917.
D D Morris G Gaulin P J Strzemienski P Spencer 《Veterinary immunology and immunopathology》1987,16(3-4):173-184
Comparison of neutrophil function was made between 8 clinically normal pony foals (3 to 7 days of age), and their dams. Random migration, stimulated migration to zymosan-activated serum, bacterial phagocytosis and bactericidal capacity of neutrophils were determined in vitro. Random migration was greater (P less than 0.01) and stimulated migration was less (P less than 0.01) in foals than in their dams. Bacterial phagocytosis and bactericidal capacity of neutrophils were not different (P greater than 0.05) between foals and mares. Results of this study suggested that neonatal foals have altered neutrophil locomotion, when compared to their dams. 相似文献
918.
B DiFranco J Schumacher D Morris 《Journal of the American Veterinary Medical Association》1992,201(7):1035-1037
Three horses were admitted for retrieval of polyurethane nasogastric tube fragments. The fragments were removed from the esophagus or stomach of 2 horses by manipulation of a snare introduced through the biopsy port of an endoscope. The fragments were surgically removed from the stomach of the third horse. 相似文献
919.
R.M. Morris 《Agricultural Systems》1980,5(4):267-278
The efficiency of transfer of food energy across various components of the human food chain is calculated for the UK. The processing and presentation stages have overall efficiencies of transfer of 0·75 and 0·93, respectively, with foods of animal origin mainly showing higher efficiencies of transfer through these processes. The efficiency of agriculture, related to a hypothetical maximum potential biomass production, is 0·026, with relatively lower efficiencies for the livestock industries. Yields of food energy from crops and livestock in the UK are calculated as 33 and 4 GJ per hectare, respectively. The factors affecting animal feed conversion efficiency are examined and it is shown that there is a potential conflict between high animal feed conversion and overall food chain efficiency. The consequences of this conflict—and possibilities for optimisation—are examined in terms of a simple resource allocation model. 相似文献
920.