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Michael A. Samaan Joshua T. Weinhandl Sebastian Y. Bawab Stacie I. Ringleb 《Computer methods in biomechanics and biomedical engineering》2016,19(16):1721-1729
Musculoskeletal modeling allows for the determination of various parameters during dynamic maneuvers by using in vivo kinematic and ground reaction force (GRF) data as inputs. Differences between experimental and model marker data and inconsistencies in the GRFs applied to these musculoskeletal models may not produce accurate simulations. Therefore, residual forces and moments are applied to these models in order to reduce these differences. Numerical optimization techniques can be used to determine optimal tracking weights of each degree of freedom of a musculoskeletal model in order to reduce differences between the experimental and model marker data as well as residual forces and moments. In this study, the particle swarm optimization (PSO) and simplex simulated annealing (SIMPSA) algorithms were used to determine optimal tracking weights for the simulation of a sidestep cut. The PSO and SIMPSA algorithms were able to produce model kinematics that were within 1.4° of experimental kinematics with residual forces and moments of less than 10 N and 18 Nm, respectively. The PSO algorithm was able to replicate the experimental kinematic data more closely and produce more dynamically consistent kinematic data for a sidestep cut compared to the SIMPSA algorithm. Future studies should use external optimization routines to determine dynamically consistent kinematic data and report the differences between experimental and model data for these musculoskeletal simulations. 相似文献
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The germination of whole seeds of celery (Apium graveolens L.) was inhibited by paclobutrazol, ancymidol and lower concentrations of uniconazole. The growth retardants daminozide, AMO 1618 and chlormequat chloride inhibited the germination of cut seeds only, indicating that the seed coat prevents the penetration of these compounds at the examined concentrations. Application of a mixture of the gibberellins A4 and A7 (GA 4/7) reversed the inhibition of all the examined growth retardants. Cytokinins (artificial or natural) had no effect when applied alone and did not interact with GA4/7 in the light. However, in the dark the cytokinins at some concentrations and GA4/7 had a synergistic effect in reversing the inhibition caused by growth retardants to whole seeds or in promoting the germination of whole seeds. It is therefore suggested that the major effect on seed of exogenous cytokinins when applied together with GA's is to increase the uptake of gibberellins by the seeds.Abbreviations AMO 1618
(2 isopropyl-5-methyl-4-trimethylammonium chloride-phenyl-1-Piperidinium-carboxylate
- ancymidol
-cyclopropyl-[4-methoxyphenyl]-5-pyrimidinemeth anol]
- chlormequat chloride
2-chloroethyltrimethylommonium chloride
- daminozide
succinin acid 2,2-diamethyl hydrazide
- paclobutrazol
[2 RS, 3 RS]-1-(4-chlorophenyl)-4,4-dimethyl-2-(1 H-1,2,4-triazol-1-yl) pentan-3-ol
- uniconazole
(E)-1-(P-chlorophenyl)-4,4-dimethyl-2-(1,2,4 triazol-1-yl)-1 penten-3-ol 相似文献
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Julita?Rabiza- widerEmail author Aleksandra??ukaszewska Ewa?Skutnik Zbigniew?Rybka Mariusz?Wachowicz 《Acta Physiologiae Plantarum》2004,26(4):411-415
The effects of a 24 hrs pulse conditioning with GA3 or BA on the lipoxygenase activity and the expression of the lipoxygenase gene were studied in senescing cut leaves of Zantedeschia aethiopica Spr. and Hosta ‘Undulata Erromena’, respectively. The GA3 treatment in Zantedeschia and the BA treatment in Hosta prevented increases the activity of lipoxygenase in senescing cut leaves. No effects of growth regulators on the lipoxygenase
gene expression were observed in cut leaves of both species. 相似文献
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Abstract: Carabid beetles were sampled by pitfall traps in May–September 2002 and 2003 in an experimental organic strawberry field in seven different mulching row treatments and in fescue-growing row spaces to determine the effect of mulches on carabid activity–density and species composition. There were no differences between treatments or row spaces in total numbers of all carabid species in either season. Of the 67 identified species and 4374 individuals, the most trapped ones were Clivina fossor (11.7% of total catch), Dyschirius globosus (10.2%), Patrobus atrorufus (9.3%), Pterostichus niger (8.8%), Bembidion properans (7.4%), Pterostichus melanarius (6.0%), Bembidion lampros (5.7%), Pterostichus crenatus (5.7%), Amara communis (4.1%), Trechus secalis (3.9%), Pterostichus strenuus (3.9%), Loricera pilicornis (3.1%), Harpalus rufipes (2.8%) and Carabus nemoralis (2.6%). Large carabid species P. niger and P. melanarius were trapped more in all mulched rows than in row spaces, and C. nemoralis was trapped more in the mixture of pine woodchip/buckwheat husk mulch than in row spaces, barley straw and birch woodchip mulch. The small but abundant species P. atrorufus was trapped more in buckwheat husk mulch than in row spaces and B. properans in row spaces than in buckwheat husk mulch. H. rufipes , being also a pest in strawberry, was trapped more in cut grass mulch than in row spaces. The Shannon H' diversity index was significantly higher in the mixture of pine woodchip/buckwheat husk mulch than in black plastic, buckwheat husk mulch or in row spaces, and in birch woodchip and cut grass mulches than in row spaces. The results of trapping studies show the species preference to the specific mulches, and reflect positive or negative effect of mulches on carabid diversity with consequences to plant protection. 相似文献
48.
The peripheral nervous system (PNS) of Drosophila provides a very well-characterized model system for studying the genes involved in basic processes of neurogenesis. Because of its simplicity and stereotyped pattern, each cell of the PNS can be individually identified and the phenotypic consequences of mutations can be studied in detail. Thus, some of the genetic mechanisms leading to the formation of type I sensory organs, the external, bristle-type sensory organs (es), and the internal, stretch-receptive chordotonal organs (ch) have been elucidated. Each sensory organ seems to be generated by a stereotyped pattern of cell division of individual ectodermal precursor cells. Recent advances in cell lineage analysis of the PNS have provided a detailed picture of almost all the lineages in the PNS, including those giving rise to the type II sensory neurons, also known as multiple dendritic (md) neurons. This knowledge will be instrumental in the precise characterization of the phenotypes associated with mutations in known and new genes and their interactions which determine cell fate decisions during neurogenesis. Here, we describe and compare three recently developed methods by which cell lineages have been assessed: single cell transplantation, bromodeoxyuridine (BrdU) incorporation studies, and the flp/FRT recombinase system from yeast. In the light of a more complete knowledge of the PNS lineages, we will discuss the effects of known mutations that alter neuronal cell fates. © 1996 Wiley-Liss, Inc. 相似文献
49.
定植期和定植密度对温室单头切花菊外观品质的影响 总被引:2,自引:0,他引:2
定植期和种植密度是影响切花菊外观品质的重要栽培措施.本文以单头切花菊‘神马’(Chrysanthemum morifolium cv. Shenma)为材料,研究定植期和密度对温室单头菊外观品质的影响.结果表明,在试验的定植期和密度范围内,随着定植期的延迟、密度的增加,单头菊株高增加,单株叶数、茎直径减小,单株鲜质量降低,花颈长度增加,花朵直径减小,但密度对株高的影响不大.在上海地区非加温温室单头切花菊生产中,以生产A级产品为目标的适宜定植期为8月中旬,适宜种植密度为64株·m-2;以生产B级产品为目标的适宜定植期为8月中旬至9月初,适宜种植密度为72~80株·m-2.本研究为建立基于光、温和密度的温室单头切花菊外观品质预测模型提供了参考. 相似文献
50.
5种食用色素对百合切花的染色效应 总被引:5,自引:0,他引:5
探讨5种食用色素对百合切花的染色效应。结果表明,百合花对果绿、柠檬黄适应性较好,其次为胭脂红、苋菜红、日落黄。不同食用色素适宜的染色浓度和染色时间有所差异,果绿15 g/L、21 h,柠檬黄11.25 g/L、12 h,胭脂红15 g/L、10 h,苋菜红11.25 g/L、20 h,日落黄15 g/L、17 h;pH值对染色效应影响不显著,各染料溶于蒸馏水时的pH值即可达到较好效果。染色后百合花瓶插寿命稍有缩短,但能达到切花所要求的7~9 d观赏期。 相似文献