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The potential of using composting technology to remediate clayey soils with high levels of crude oil contamination was evaluated. An open air windrow comprised of flare pit soil, manure and wood chips was constructed at Olds College, Composting Technology Centre. Aeration and mixing were carried out by a skid steer loader and composting parameters were monitored for ten months. Temperature profile of this windrow gave cyclic patterns of high and low temperature recordings corresponded to the turning events. Most of the microbial metabolic activity occurred within the mesophilic temperature range and the hydrocarbon degrading microorganism populations remained high throughout the trial. Complete removal of BTEX compounds was achieved within six months and extractable carbons from C5 to C10 were reduced by 98.7% compared to the initial contaminated soil. Vegetative growth on the composted soil was also evaluated. Barley and timothy plants grown in the composted soil were compared to the control off-lease soil, contaminated soil, and other treatments of varying salinity and organic matter levels. Plant germination, survival, and biomass production was significantly better in the composted soil than in the contaminated soil. Furthermore, barley plants grown in the composted soil were more resilient than those grown in the control off-lease soil.  相似文献   
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A previously published TaqMan PCR test for R. solanacearum race 3 biovar 2 was modified to enable both the validation of negative results and the confirmation of positive results in a closed-tube system. Negative results were validated through the use of a reaction control plasmid, designated pRB2C2, which was designed to generate a 94bp product using the same amplimers targeting the primary diagnostic 68bp sequence in R. solanacearum race 3 biovar 2 DNA. SYBR Green was included in the reaction mix to facilitate the identification of post-reaction products using melt peak analysis. The 94bp reaction control had a melt peak temperature of about 90°C, while the diagnostic target amplicon had a melt peak temperature of about 83°C; thus positive results could be easily confirmed and distinguished from the reaction control product. Addition of pRB2C2 at 100 copies per reaction had no effect on the sensitivity of the TaqMan assay for R. solanacearum race 3 biovar 2, and the modified assay successfully detected R. solanacearum race 3 biovar 2 in infected, asymptomatic tomato stems and leaves as well as in potato tubers and stems.  相似文献   
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Invertebrate meals (e.g. polychaetes and insects) present novel and sustainable high‐quality nutrient sources for use in fish feed formulations. To test this innovative source, an eleven‐week feeding trial was conducted evaluating the effects of replacing the fishmeal (FM) component as an example of a superior protein source (FM CTRL) with ragworm meal (RW, Nereis virens) and/or silkworm pupae (SWP, Bombyx mori) in mirror carp (Cyprinus carpio) diets. Three experimental diets with partial replacement of FM (diets: RW + FM, SWP + FM and RW + SWP + FM) were formulated. All diets were formulated to be iso‐nitrogenous, iso‐lipidic and iso‐energetic. Growth performance and feed utilization indices were assessed, and the feeding trial concluded with the analysis of haematological parameters to provide an indication of carp physiological and health status. Mean weight gain was greatest in mirror carp fed RW + FM (60.83 fish?1 day?1; P < 0.05 vs. all other diets) followed by SWP + FM (40.62 g fish?1 day?1; P < 0.05 vs. all other diets). The least weight gain was achieved in fish fed FM + SWP + RW+ and FM CTRL (34.34 and 33.96 g fish?1 day?1, respectively; not significantly different from each other). Fish fed on RW + FM diet had significantly lower plasma ammonia concentrations than any other dietary groups (= 0.04). Mirror carp fed on SWP + FM diet (111.52 units mL?1) were observed to have a marked enhancement in alternative complement activity than FM CTRL (79.21 units mL?1, = 0.041). Both ragworm and silkworm pupae meal present attractive sustainable functional feed component in carp diets, with benefits on enhancing growth performance and specific physiological parameters.  相似文献   
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Partial least squares (PLS) regression modeling was used to relate the antifungal activity of Bacillus subtilis solid-state fermentation extracts to the individual high-performance liquid chromatography (HPLC) peaks from those extracts. A model was developed that predicted bioassay inhibition based on the extract HPLC profile (R(2) = 0.99). Concentrations of the members of the antifungal lipopeptide families iturin A and fengycin were found to correlate positively with extract inhibition, but a peak with unidentified chemical composition (designated as peak 48) showed the strongest correlation with extract inhibition. HPLC data were used to construct models for the production of iturin A, fengycin, and peak 48 as a function of the substrate moisture content, incubator temperature, and aeration rate in the solid-state bioreactors. Maximum production of all compounds occurred at the highest moisture content (1.7 g/g dry basis) and lowest incubator temperature (19 degrees C) tested. Optimal aeration rates for the production of the two known lipopeptides and peak 48 were 0.1 and 1.5 L/min, respectively.  相似文献   
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Black cohosh is a commonly used botanical dietary supplement for the treatment of climacteric complaints. Because the opiate system in the brain is intimately associated with mood, temperature, and sex hormonal levels, the activity of black cohosh extracts at the human mu opiate receptor (hMOR) expressed in Chinese hamster ovary cells was investigated. The 100% methanol, 75% ethanol, and 40% 2-propanol extracts of black cohosh effectively displaced the specific binding of [3H]DAMGO to hMOR. Further studies of the clinically used ethanol extract indicated that black cohosh acted as a mixed competitive ligand, displacing 77 +/- 4% [3H]DAMGO to hMOR (Ki = 62.9 microg/mL). Using the [35S]GTPgammaS assay, the action of black cohosh was found to be consistent with an agonist, with an EC50 of 68.8 +/- 7.7 microg/mL. These results demonstrate for the first time that black cohosh contains active principle(s) that activate hMOR, supporting its beneficial role in alleviating menopausal symptoms.  相似文献   
47.
Toxicosis associated with benzimidazole anthelmintics has been reported with increasing frequency in zoologic collections. Clinical signs, clinicopathologic abnormalities, and gross and histologic lesions are primarily the result of damage to the gastrointestinal and hematopoietic systems. Profound leukopenia, especially granulocytopenia, is the most common and severe clinicopathologic change associated with benzimidazole administration. Death usually occurs from overwhelming systemic bacterial and/or fungal infections secondary to severe immunosuppression. In this 125-day study, six male Hermann's tortoises (Testudo hermanni) were treated orally with two 5-day courses of fenbendazole 2 wk apart at a dosage of 50 mg/kg. Serial blood samples were used to assess hematologic and plasma biochemical changes before, during, and following the treatment period. Although the tortoises remained healthy, blood sampling indicated an extended heteropenia with transient hypoglycemia, hyperuricemia, hyperphosphatemia, and equivocal hyperproteinemia/hyperglobulinemia, which were considered to be in response to fenbendazole administration. Changes in several other clinicopathologic parameters appeared to correlate with fenbendazole administration. The hematologic and biochemical changes seen in the healthy animals in this study should be considered when treating compromised tortoises with fenbendazole. Hematologic and plasma biochemical status of tortoises/reptiles should be determined before treatment and monitored during the treatment period. The risk of mortality of an individual from nematode infection should be assessed relative to the potential for metabolic alteration and secondary septicemia following damage to hematopoietic and gastrointestinal systems by fenbendazole.  相似文献   
48.
Dilated cardiomyopathy recently has been recognized in juvenile Portuguese Water Dogs. The purpose of this study was to evaluate unaffected and affected puppies by physical examination, electrocardiogram (ECG), echocardiogram, specific biochemical assays, and ultrastructure to document disease progression and to develop a method of early detection. Results of segregation analysis were consistent with autosomal recessive inheritance. Of 124 puppies evaluated clinically and echocardiographically, 10 were affected. No significant differences were found between unaffected and affected puppies for blood and myocardial carnitine or taurine concentrations, serum chemical variables, results of ophthalmological examinations, ECGs, or measurement of urine metabolites. Ultrastructural examination of myocardium from affected dogs revealed myofibrillar atrophy and small regions of myofibrillar degeneration, most prominently at the region of the intercalated discs. Only echocardiography allowed detection of affected puppies before clinical signs became evident. Echocardiography revealed a significant difference in the shortening fraction, E point to septal separation, and the end systolic and diastolic left ventricular internal diameters. Affected puppies were detected 1-4 weeks before the development of acute congestive heart failure.  相似文献   
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