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101.
Soil adjacent to new brick veneer work is likely to have a higher pH owing to the mixture of cement with the soil. In the Gainesville, FL, area, soil samples taken from such locations had a range of pH values from 9.0 to 10.1; similar soils used in bioassays had a pH of 5.6 before the addition of cement. Addition of 15 mg of Portland cement to 33 g of soil increased the pH to 6, and addition of 291 mg of Portland cement increased the pH to 9. The pH of soil amended with cement was stable for the first 5 months. After 10 months, soil pH values decreased from alkaline to near neutral in all cases. Eastern subterranean termite workers, Reticulitermes flavipes (Kollar), were exposed to the treated soil at pH 6-9 for 24 h, and percentage mortality was recorded at 5 days, 5 months and 10 months. Termite mortality significantly decreased at higher soil pHs for bifenthrin, chlorpyrifos, fipronil and imidacloprid treatments at 5 months and similarly for bifenthrin, permethrin, chlorpyrifos, fipronil and imidacloprid treatments at 10 months. There was an inverse linear relationship between soil pH and mortality. Increased soil pH diminished residual activity of termiticide in the following order: imidacloprid > fipronil > chlorpyrifos = bifenthrin > permethrin > cypermethrin.  相似文献   
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Two digestion and metabolism experiments were conducted to determine effects of monensin in low-protein diets. Monensin supplementation (27 mg/kg of diet dry matter) of steers (303 kg) fed 8.7% crude protein increased (P less than .01) apparent N digestibility and N retention and decreased (P less than .01) percentage of N apparently absorbed lost in urine. Apparent digestibilities of dry matter, gross energy and acid detergent lignin were increased (P less than .05). Digestibilities of neutral detergent and acid detergent fibers were not affected by monensin. In growing wether goats (15 kg) fed 8.5% crude protein, monensin (23 mg/kg of diet dry matter) improved (P less than .01) apparent N digestibility and apparent N absorption. However, urinary N excretion also increased (P less than .05), resulting in no difference in N retention. Monensin did not affect digestibilities of dry matter or gross energy. Efficiency of feed conversion and average daily gain were improved with monensin supplementation of growing goats fed a low-protein, high-roughage diet. Monensin resulted in typical shift of acetate-to-propionate ratio in both experiments. Results suggest that improved N utilization may account for some benefits of feeding monensin.  相似文献   
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Satellite remote sensing of breeding habitat for an African weaver-bird   总被引:2,自引:0,他引:2  
Data derived from the Advanced Very High Resolution Radiometer (AVHRR) on board the NOAA series of operational, polar orbiting, meteorological satellites have previously been shown to be quite useful for monitoring vegetation dynamics at scales ranging from regional (104 km2) to global. In this report, we demonstrate that these same data can be used to monitor potential breeding habitat for a highly mobile, granivorous African weaver-bird, the red-billed quelea (Quelea quelea). This species is often considered to be an agricultural pest, affecting cereal production throughout sub-Saharan Africa. The temporal resolution and very large (continental) spatial coverage provided by these data can provide a unique context within which to examine species distribution and abundance patterns.  相似文献   
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Effects of photoperiod on growth, eating patterns and clearance rate, secretion rate and half-life of growth hormone in serum were assessed in Holstein heifers. Sixty-four prepubertal heifers (avg body wt 102 kg) were blocked by weight into four groups of 16. Within block, each animal was randomly assigned to one of four photoperiod treatments: 16 h of cool-white fluorescent light:8 h dark (CW-16L:8D), CW-8L:16D, CW-6L:8D:2L:8D or 16 h of VitaLite fluorescent light:8D (V-16L:8D). Animals were fed ad libitum a complete mixed diet formulated for heifers to gain approximately .9 kg/d. Average daily body weight gains were .93, .96, .98 and 1.0 kg/d during 112 d of exposure to CW-8L:16D, CW-6L:8D:2L:8D, CW-16L:8D and V-16L:8D, respectively. Heifers exposed to V16L:8D and CW-16L:8D gained more weight (112 and 110 kg; P less than .05 and P less than .08, respectively) than heifers exposed to CW-8L:16D (104 kg). Body weight gain was not different (P greater than .10) between heifers exposed to CW-6L:8D:2L:8D (108 kg) or CW-8L:16D, or between heifers exposed to CW-16L:8D or V-16L:8D. Total number of eating events in 30 h and percentage of total events in the lighted period were 549 and 96% and 523 and 50% in heifers exposed to CW-16L:8D and CW-8L:16D, respectively. Clearance rates (620 vs 636 ml/min), secretion rates (3.0 vs 3.8 micrograms/min) and half lives (17.2 vs 17.9 min) of growth hormone in serum were similar in heifers exposed to CW-16L:8D and CW-8L:16D.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.
Technetium-99m hexamethylpropyleneamine oxine (99mTc-HMPAO) and Indium-111 oxine (111In-oxine) labeled canine gramulocytes were evaluated in vitro over a six hour period. Labeling efficiency for 99mTC-HMPAO and 111In-oxine labeled granulocytes was 39.6%± 8.0% and 60.6%± 17.6% (mean ± SD) respectively. The mean in vitro elution of the radiolabel ranged from 8.7-14.0% for the 99mTc-HMPAO grannulocytes and from 6.1-9.0% for the 111In-oxine granulocytes. Mean cell viability, for the 99mTc-HMPAO, 111In-oxine and non-radiolabeled control granulocytes ranged from 97.8-99.4%, 96.4-98.5% and 98.2-99.0%, respectively. The phagocytic ability of the 99mTc-HMPAO, 111In-oxine and control granulocytes ranged from 47.5-54.1%, 38.9-56.2% and 46.6-57.8% respectively over the six hour study period. Although labeling efficiency using 111In-oxine was significantly (P=0.05) better than 99mTc-HMPAO, there was no significant difference in label retention of the two radiolabels. There was no significant difference in viability or phagocytic function during the six hour study period. Considering the potential cost advantage and the superior imaging qualities of Technetium-99m relative to Indium-111, 99mTc-HMPAO appears to be a good alternative to 111In-oxine as a granulocyte label.  相似文献   
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