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11.
The enzyme, aryl acylamidase, was characterized in propanil-susceptible and propanil-resistant barnyardgrass with respect to kinetic parameters, the effects of inhibitors, and the levels of activity in dark- and light-grown tissues. The enzyme reaction in the resistant tissue preparation proceeded linearly with time over a 5 h time course, while activity in the susceptible tissue preparation was 2- to 4-fold lower and the activity tended to decrease after 2 h. The apparent Km values were 62.1 mmol L−1 and 3.1 mmol L−1 for the enzyme activity in the susceptible and resistant tissue preparations, respectively. Two herbicides (anilofos and piperophos), previously shown to synergize propanil injury against the resistant biotype, were found to be potent inhibitors of the in vitro aryl acylamidase activity. 相似文献
12.
In greenhouse and field experiments, an oil-in-water emulsion of unrefined corn oil and Silwet L-77 increased the biological weed control efficacy of Colletotrichum truncatum (Schw.) Andrus et Moore for control of the weed, hemp sesbania ( Sesbania exaltata [Raf.] Rydb. ex A.W. Hill). The surfactant – corn oil emulsion stimulated germination and appressoria formation in vivo and in vitro and delayed the need for dew. We hypothesize that the corn oil protected the conidia from desiccation during the dew-free period and the surfactant stimulated spore germination and appressoria formation. In field experiments conducted over 3 years, a single application of a 50% (v/v) unrefined corn oil tank mixture containing 0.2% (v/v) Silwet L-77 surfactant controlled hemp sesbania in soybeans an average of 95%. Aqueous fungal suspensions or adjuvants alone did not visually affect or control hemp sesbania. The soybean yields were significantly higher in the plots where weeds were effectively controlled. These results suggest that formulating C. truncatum in unrefined corn oil and surfactant greatly increases its infectivity and the biocontrol potential of this pathogen. 相似文献
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ROBERT K. WANSBROUGH 《Australian veterinary journal》1996,74(1):59-63
Summary: The anatomy of the canine tail and its relationship to the physiological functions of the tail are described and the effect of tail docking on these is discussed. Current knowledge on the physiology and anatomy of pain is described with particular reference to cosmetic tail docking in the neonatal puppy. Recent advances in knowledge about pain and the changes in approach to pain management, refute the premise that 'puppies do not feel pain therefore tail docking is not inhumane' and also the premise that 'the pain and the effects of tail docking are insignificant.' Six criteria to test the 'necessity' to dock dogs are presented; this article shows that the reasons advanced for tail docking do not satisfy these criteria and so that docking dogs' tails cannot be justified. 相似文献
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DANIEL C. KNUDSEN F. ROBERT JACOBS DENNIS CONWAY MEGAN K. BLAKE 《Growth and change》1994,25(2):183-205
This paper presents results of a hierarchical, fixed-question survey that sought responses about flexible machining cells, flexible labor cells, and concurrent changes in plant operations among nonelectrical machinery manufacturers in Illinois, Indiana, Michigan, Ohio, and Wisconsin. General results indicate that the majority of firms in the American Midwest do not possess flexible manufacturing capability. Of those that do possess this capability, most adopted flexible labor cells prior to adopting flexible machining cells. These cells are small, employing relatively few workers and producing a limited line of products. While the adoption process has been plagued with training, scheduling, and integration problems, most plant managers are pleased with the performance of their flexible manufacturing cells. Management has been reluctant to break out of traditional relationships with suppliers, to trim levels of management and to explore strategic alliances with competitors. Survey results are disaggregated by year, size, positon-in-organization, and by union affiliation. 相似文献
15.
DAVID A. JIMNEZ ROBERT T. O'BRIEN JOHNA D. WALLACE EMILY KLOCKE 《Veterinary radiology & ultrasound》2011,52(2):196-200
Nine normal juvenile dogs were evaluated with direct jejunal contrast‐enhanced ultrasonography via midline celiotomy. Three different doses of ultrasound contrast medium (Definity®) were injected through a peripheral venous catheter. Time‐intensity curves were used to calculate baseline, time to initial rise, inflow slope, time‐to‐peak, peak intensity (PI), and outflow slope for each administered dose. PI was directly proportional to dose. Outflow slope was similar for all patients, independent of dose. The most favorable images were acquired with a dose of 0.030 ml/kg given as a rapid intravenous manual bolus. The technique and normal jejunal perfusion pattern described herein may provide useful data for evaluation of intestinal vascular, inflammatory, and neoplastic disease in the dog. 相似文献
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A. HATTON J. RANGER M. ROBERT C. NYS P. BONNAUD 《European Journal of Soil Science》1987,38(2):179-190
A mica was inserted into the soil at four sites to try to identify, in situ , the physico-chemical changes in the soil caused by the introduction of different tree species, and especially conifers. Changes in the chemistry and mineralogy of the mixed-layered mica, mica-chlorite, vermiculite, after 1 1 /2 and 31 /2 years in the soil, showed good differentiation between soil horizons and between soil types. Differences due to tree species were present, but small. The mechanisms of mineral evolution can be defined with reference to experimental data obtained in the laboratory. In litter layers, the mica-chlorite sheet was transformed into a mica-vermiculite, and exchangeable cations predominated on the exchange sites. In the organo-mineral horizons, changes varied depending on the soil type: in the podzol, transformation was similar to that in the litter layers, but in the sol brun acide , changes were dominated by the Al fixation on the exchange sites and its rapid hydroxylation which blocks these sites, leading to the formation of Al intergrade minerals.
Different tree species produced deviations linked to their ability to cycle cations, and also to the different organic materials produced which can attack the mineral.
The method has the potential to define the present soil environment and weathering processes, but it needs a more complete experimental design and the use of statistics to clarify the effects of the parameters and their interactions. 相似文献
Different tree species produced deviations linked to their ability to cycle cations, and also to the different organic materials produced which can attack the mineral.
The method has the potential to define the present soil environment and weathering processes, but it needs a more complete experimental design and the use of statistics to clarify the effects of the parameters and their interactions. 相似文献
18.
The chlorophyll production of wheat (Triticum vulgare L. cv. Mericopa), corn (Zea mays L. cv. Everta), and alfalfa (Medicago sativa L. cv. Saranac), treated with the herbicide 4-chloro-5-methylamino-2-(3-trifluoro-methylphenyl)pyridazin- 3-one (norflurazon) and grown under high light intensity (10 760 lux) was markedly reduced. Corn and wheat seedlings germinated and grown for 7 days in an agar medium containing 1 mg/1 norflurazon were almost completely bleached. Alfalfa was even more sensitive to norflurazon, 0.1 mg/1 causing almost complete chlorosis. Under low light intensity (10.76 lux) the influence of norflurazon on chlorophyll production was greatly reduced. It is thought that norflurazon inhibits carotenoid synthesis leaving the chlorophyll of the plant subject to photooxidation. Electron micrographs of chloroplasts from green, partially bleached, and bleached areas of corn leaves treated with norflurazon indicate that the herbicide causes progressive deterioration of the lamellar system. 相似文献
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