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This study aimed to evaluate the effect of years and different locations, beef cattle manure compost (BCMC) and mixed oilseed cake (MOC) application rates on bulb and scale characteristics, nutrient content and nutrient uptake in bulb and leaf, and storage quality of intermediate-day onions (Allium cepa L.) at two organic onion growers' fields during the 2012/2013 and 2013/2014 growing seasons. Treatments included BCMC applied at rates of 0, 30 ton·ha-1 and MOC applied at rates of 0, 3, 6, 9 t·ha-1. Average temperature at two experimental locations during the growing season in 2013/2014 was 1.2°C higher than in 2012/2013, while total rainfall was 206.6 mm higher in 2012/2013 than in 2013/2014. Onion bulb diameter, bulb fresh weight, scale thickness and fresh leaf weight were significantly greater in 2013 than in 2014, but bulb dry matter was greater in 2014 than in 2013. Nitrogen, potassium (K) and magnesium (Mg) contents and uptakes in bulb were significantly higher in 2013/2014 than in 2012/2013. BCMC application at 30 t·ha-1 rate increased K and Mg contents in bulb and leaf as compared with no BCMC. Total soluble solids (TSSs), pyruvic acid (PA), total phenolics (TPs) and total flavonoids (TFs) contents were higher in 2013/2014 than in 2012/2013. BCMC application at 3 t·ha-1 decreased TSSs and PA content compared with no BCMC. MOC application increased PA content. Rot and weight loss on 8 September in cold room storage were lower in 2013/2014 than in 2012/2013, but the loss on 14 October and 10 December were not significantly different between two years. In conclusion, high air temperature and low rainfall in Mar. and Apr. increased fresh bulb weight and bulb thickness, while high temperature, low rainfall and long sunshine duration increased TSSs, PA, TPs and TFs contents. Compost and oilseed cake application increased fresh bulb weight, scale thickness, while they decreased TSSs and did not affect organic compounds.  相似文献   
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The oriental fruit fly, Bactrocera dorsalis (Hendel), is a major polyphagous insect pest with a worldwide distribution. The effects of temperature on stage-specific development in B. dorsalis were investigated at eight constant temperatures (13.0 °C, 14.4 °C, 16.2 °C, 19.5 °C, 23.8 °C, 27.7 °C, 31.8 °C and 34.8 °C). B. dorsalis developed successfully from the egg stage to the adult stage at all the tested temperatures, except at the lowest temperatures (13.0 °C and 14.4 °C). Stage-specific lower developmental thresholds and thermal constants were determined using linear regression. The lower and higher temperature threshold (TL and TH, respectively) were estimated using the Sharpe-Schoolfield-Ikemoto model. The lower developmental threshold and thermal constant from egg to adult emergence were 9.8 °C and 325.5 degree-days, respectively. The intrinsic optimum temperatures of the egg, larval, pupal and egg to pupal stage were 20.7 °C, 21.8 °C, 21.1 °C, and 22.4 °C, respectively. The temperature range of the B. dorsalis total immature stage from TL to TH was 20.4 °C (13.8 °C - 34.2 °C). The stage-specific developmental completion of B. dorsalis was determined using a two-parameter Weibull function. The daily adult emergence frequency of B. dorsalis was estimated in relation to adult age and temperature using non-linear developmental rate functions and the Weibull function. The date of cumulative 50% adult emergence estimated using non-linear functions was approximately one day earlier than the experimentally observed date. Thermal performance was compared among B. dorsalis populations from different locations.  相似文献   
645.
For bacterial inoculants to be effective in soil remediation, the bacterial strain must be capable of overcoming any negative effects of soil minerals on cellular processes. One class of minerals commonly encountered by soil bacteria is clays. Thus, the effect of commonly occurring clay minerals in soils on starvation, survival and 2-hydroxypyridine catabolism by Arthrobacter crystallopoietes was evaluated. Stationary phase A. crystallopoietes cells were suspended in 0.03M, pH7.0, phosphate buffer containing no clay or amended with 0.2% (wt/vol) montmorillonite, sodium montmorillonite or kaolinite. Marked effects of clay minerals on both survival rates and catabolic rates of 2-hydroxypyridine were noted. For example, after 14 weeks starvation, 4.6% of the initial cell population was viable with no clay present, compared to 0.8% (montmorillonite), 22.1% (kaolinite) and 54.1% (sodium montmorillonite) in the presence of the clay minerals. Acclimated and nonacclimated cell populations were used to evaluate 2-hydroxypyridine catabolism. Induction of 2-hydroxypyridine metabolism occurred in the unacclimated cells following starvation. Differential impact of the clay minerals on unacclimated cells was detected. Montmorillonite enhanced the capacity for induction of 2-hydroxypyridine catabolism and its decomposition rate after 0–3 days starvation. For acclimated cells, clay did not affect the metabolic activity prior to starvation, but the presence of clay resulted in increased activity during starvation. For example, after 3 days starvation, a nearly two fold increase in metabolism was detected in the presence of clay minerals. These data suggest that some clay minerals in soil alter the survival time and metabolic activity of soil-amended bacteria, thereby affecting the potential for bioremediation success. Received: 1 March 1996  相似文献   
646.
Clinical pharmacokinetic profiles were investigated following intramuscular (i.m.) administration to pigs with a commercial tylosin-florfenicol combination product at a dose of 2.5 mg/kg tylosin and 5 mg/kg florfenicol or 10 mg/kg tylosin and 20 mg/kg florfenicol. The quantitation limit (QL) of florfenicol was 0.1 microg/ml, the inter-day and intra-day precision (CV%) were both beow 10%. The quantitation limit (QL) of tylosin was 0.05 microg/mL. The pharmacokinetic characteristics after i.m. doses were fitted by a one compartment open model. A fourfold decrease in the normal dose of each drug (20 mg/kg to 5 mg/kg for florfenicol, and 10 mg/kg to 2.5 mg/kg for tylosin) resulted in a corresponding two fold decrease in each drug of the maximum plasma concentration (C(max)) and the area under curve (AUC) values.  相似文献   
647.
We examined the age-related changes of calbindin D-28k (CB)-immunoreactive neurons and overall populations of neurons in the myenteric plexus of gerbil duodenum using whole mount preparations and immunohistochemistry. The circumference of duodenum increased age-dependently. CB-immunoreactive neurons were observed in all groups, and most of them had the Dogiel type II morphology. The fully developed cobweb-like structures were observed in the myenteric plexus of duodenum at postnatal month (PM) 3 to 24. Although the highest numbers of CB-immunoreactive neurons and overall population were observed in PM 1.5, it is related with significant increase of the size of circumference between PM 1.5 to PM 3. CB-immunoreactive neurons were slightly decreased with age between PM 3 to PM 24. We have also found that whole numbers of myenteric neurons were also significantly decreased in PM 24 group. These results suggest that loss of overall numbers of myenteric neurons and CB-immunoreactive neurons may be related with age-related neurodegeneration and functional loss of duodenum in the gerbil.  相似文献   
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We describe a 10-month-old, intact female American Cocker Spaniel with pulmonary lymphomatoid granulomatosis (PLG). On clinical examination, this dog presented with nonproductive dry cough, serous nasal discharge, dyspnea, and lack of appetite. Radiography showed a consolidated lesion in the left cranial lung lobe. Histopathologic examination showed a mixed population of atypical lymphoid cells that had infiltrated into the pulmonary blood vessels angiocentrically. The lymphocytes were CD3 positive, consistent with a pan-T-cell phenotype. The lymphoid cells in the lesion were also positive for CD20cy and CD79a, indicative of the presence of B cells. We also observed large Reed-Sternberg-like cells that were positive for CD15 and CD30, similar to observations in human pulmonary Hodgkin's disease (PHD). In conclusion, canine PLG in this Cocker Spaniel was associated with B and T cells, which is first identified in a case of canine PLG. It was histopathologically similar to human lymphomatoid granulomatosis and immunophenotypically similar to human PHD.  相似文献   
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