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Protected cultivation of ornamental flowers, as a commercial venture, becomes less profitable with excessive use of fertilizers. The present study examined the influence of microbial biofilm inoculants (Anabaena–Azotobacter, Anabaena–Trichoderma and Trichoderma–Azotobacter) on the availability of soil nutrients and structure of rhizosphere microbial communities in three varieties of chrysanthemum (var. White Star, Thai Chen Queen and Zembla). Varietal-specific responses in growth, enzyme activities, flower yield of plants and availability of soil nutrients were recorded. Dehydrogenase activity was highest in var. White Star treated with the Anabaena–Trichoderma biofilm inoculants. The Anabaena–Azotobacter inoculant enhanced the availability of nitrogen, phosphorus and micronutrients in the soil, besides 40–50% increase in soil organic carbon, as compared to carrier alone or no inoculation. PCR-DGGE profiling of the cyanobacterial communities and qPCR quantification of 16S rRNA abundance of bacteria, archaea and cyanobacteria in the rhizosphere soils, revealed the stronger influences of these inoculants, especially in var. Zembla. Principal Component Analysis (PCA) helped to illustrate that the enhanced microbe-mediated availability of soil macro-and micronutrients, except iron content (Fe), was the most influential factor facilitating improved plant growth and yield parameters. The Anabaena–Azotobacter, and Anabaena–Trichoderma biofilm inoculants, proved superior in all three chrysanthemum varieties. 相似文献
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In gait analysis, the concepts of Euler and helical (screw) angles are used to define the three-dimensional relative joint angular motion of lower extremities. Reliable estimation of joint angular motion depends on the accurate definition and construction of embedded axes within each body segment. In this paper, using sensitivity analysis, we quantify the effects of uncertainties in the definition and construction of embedded axes on the estimation of joint angular motion during gait. Using representative hip and knee motion data from normal subjects and cerebral palsy patients, the flexion-extension axis is analytically perturbed +/- 15 degrees in 5 degrees steps from a reference position, and the joint angles are recomputed for both Euler and helical angle definitions. For the Euler model, hip and knee flexion angles are relatively unaffected while the ab/adduction and rotation angles are significantly affected throughout the gait cycle. An error of 15 degrees in the definition of flexion-extension axis gives rise to maximum errors of 8 and 12 degrees for the ab/adduction angle, and 10-15 degrees for the rotation angles at the hip and knee, respectively. Furthermore, the magnitude of errors in ab/adduction and rotation angles are a function of the flexion angle. The errors for the ab/adduction angles increase with increasing flexion angle and for the rotation angle, decrease with increasing flexion angle. In cerebral palsy patients with flexed knee pattern of gait, this will result in distorted estimation of ab/adduction and rotation. For the helical model, similar results are obtained for the helical angle and associated direction cosines.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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