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31.
Fat acidity values were determined on 8 commercially available flours by the American Association of Cereal Chemists method (AACC-02-01A) and by the International Organization for Standardization method (ISO-7305). Comparisons of means obtained by these 2 methods indicated that the ISO method produced results that were 1.4-2.5 times greater (P less than 0.001) than those for the AACC method. These data are consistent with a previous report which indicated that acidic materials (phosphates and amino acids) other than fatty acids are extracted by 95% alcohol (ISO method), whereas fatty acids alone are extracted by petroleum ether (AACC method). Fat acidity values obtained by AACC methodology employing Soxhlet and continuous extraction were also compared. No difference in fat acidity means existed with respect to extraction technique except for an aged whole wheat flour sample which produced a higher value (P = 0.05) by continuous extraction.  相似文献   
32.
During aerobic composting of animal manure, microbial activity within the mixture generates heat and metabolic by-products that inactivate zoonotic pathogens. Although it is recognized that the type and level of microbial activity will vary with the nutrient availability of different compost ingredients, the degree to which these changes could impact pathogen inactivation is of interest. Towards that goal, the purpose of this study was to determine inactivation of Escherichia coli O157:H7 and Listeria monocytogenes in compost laboratory-scale bioreactor systems formulated to different initial carbon:nitrogen (C:N) ratios with cow manure, straw, and cottonseed meal. The C:N ratio did not significantly affect the time to inactivation of Listeria monocytogenes. In contrast, Escherichia coli O157:H7 survived for significantly (P < 0.05) longer periods of time in 40:1 C:N systems than in 30:1 or 20:1 systems even though the cumulative heat exposures were statistically similar in the systems. An increase of pH values to 8 to 9 occurred initially for 40:1 C:N systems, whereas the pH of the 20:1 and 30:1 systems initially declined to 5.5 to 6 before increasing to 8 to 9 after 2 days of composting.  相似文献   
33.
AIM: To assess the benefit of inducing emesis in dogs that have ingested rodenticide bait containing brodifacoum (BDF), by determining the amount of BDF in bait recovered from the vomitus relative to the estimated amount consumed.

METHODS: Between 2014 and 2015 samples of vomitus from seven dogs that ingested rodenticide baits containing BDF were submitted by veterinarians in New Zealand. All seven dogs had been given apomorphine by the veterinarian and vomited within 1 hour of ingesting the bait. Some or all of the bait particles were retrieved from each sample and were analysed for concentrations of BDF using HPLC. Based on estimations of the mass of bait consumed, the concentration of BDF stated on the product label, and the estimated mass of bait in the vomitus of each dog, the amount of BDF in the vomited bait was calculated as a percentage of the amount ingested.

RESULTS: For five dogs an estimation of the mass of bait ingested was provided by the submitting veterinarian. For these dogs the estimated percentage of BDF in the bait retrieved from the vomitus was between 10–77%. All dogs were well after discharge but only one dog returned for further testing. This dog had a normal prothrombin time 3 days after ingestion.

CONCLUSIONS AND CLINICAL RELEVANCE: The induction of emesis within 1 hour of ingestion can be a useful tool in reducing the exposure of dogs to a toxic dose of BDF. The BDF was not fully absorbed within 1 hour of ingestion suggesting that the early induction of emesis can remove bait containing BDF before it can be fully absorbed.  相似文献   

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The synthesis of massive arrays of monodispersed carbon nanotubes that are self-oriented on patterned porous silicon and plain silicon substrates is reported. The approach involves chemical vapor deposition, catalytic particle size control by substrate design, nanotube positioning by patterning, and nanotube self-assembly for orientation. The mechanisms of nanotube growth and self-orientation are elucidated. The well-ordered nanotubes can be used as electron field emission arrays. Scaling up of the synthesis process should be entirely compatible with the existing semiconductor processes, and should allow the development of nanotube devices integrated into silicon technology.  相似文献   
36.
This report describes the development of a Comparative Molecular Field Analysis (CoMFA) model from a set of obtusifoliol 14α-methyl demethylase (DM) inhibitors to aid in the design of herbicides targeting sterol biosynthesis. CoMFA is a three-dimensional (3-D) quantitative structure–activity relationship (QSAR) method that is useful in the probing of receptor binding sites when experimental structure data are unavailable. Conformational analysis and SAR of some rigid and active analogs were used to build the initial model using the active analog hypothesis. The model was subsequently used to design compounds that retain the active site shape requirements, but incorporate physical properties that favor soil-applied herbicidal action. In addition, a second-generation CoMFA model incorporating the newly designed inhibitors was developed and represents the current understanding of the DM binding site. This model was derived from a pharmacophore developed from two methods, the active analog approach as well as from the Catalyst program. The fact that two independent methods produced a similar pharmacophore strengthens the validity of the model. © 1999 Society of Chemical Industry  相似文献   
37.
The quantum-confined Stark effect in single cadmium selenide (CdSe) nanocrystallite quantum dots was studied. The electric field dependence of the single-dot spectrum is characterized by a highly polarizable excited state ( approximately 10(5) cubic angstroms, compared to typical molecular values of order 10 to 100 cubic angstroms), in the presence of randomly oriented local electric fields that change over time. These local fields result in spontaneous spectral diffusion and contribute to ensemble inhomogeneous broadening. Stark shifts of the lowest excited state more than two orders of magnitude larger than the linewidth were observed, suggesting the potential use of these dots in electro-optic modulation devices.  相似文献   
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39.
High soil pH and excessive calcium carbonate (CaCO3) in the Everglades Agricultural Area of south Florida reduce the availability of phosphorus and micronutrients to crops. Sulfur (S) amendment is recommended to reduce soil pH and enhance nutrient supply. The study’s objective was to determine the sulfur amendment effectiveness on soil pH and nutrient availability in organic soil as CaCO3 content increases in soil. An experiment of four S rates (0, 90,224, and 448 kg ha?1) and three added CaCO3 (0%, 12.5%, and 50% by volume) in organic soil was established. Sulfur application had limited effects on soil pH reduction as CaCO3 level increased and therefore failed to enhance nutrient availability; however, it increased sulfate concentration in soils, which could be at risk for export from the field. Unexpected increases in manganese concentration with added CaCO3 was associated with reducing conditions due to increased soil bulk density, which changed the soil physical properties.  相似文献   
40.
The use of reclaimed wastewater in agriculture can be a solution for regions with water shortages or low rainfall periods; besides fulfilling the crop's water needs, it would also promote the recycle of nutrients. However, care should be taken regarding soil salinization, especially in closed environments such as greenhouses for the cultivation of ornamental plants. The domestic effluents are rich in sodium which can accumulate on soil and cause soil sealing. This study evaluated the use of effluents from anaerobic filters and intermittent sand filters in the production of rosebushes (Rosa hybridaAmbiance”). The crop yield of the rosebushes irrigated with reclaimed wastewater exceeded the one obtained with traditional cultivation, reaching a value 31.8 % higher when employing nitrified effluent originated from intermittent sand filters, with no difference in the product quality. The salinity levels are below the critical limits found in the literature; however, there was a significant increase compared to the irrigation with drinking water.  相似文献   
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