Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these...Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.展开更多
The field experiment was conducted in 2005 and 2006 at Northern Japonica Rice Cultivation and Breeding Research Center, Shenyang Agricultural University,Shenyang, northeast China. Shennong 265 (typical erect panicle r...The field experiment was conducted in 2005 and 2006 at Northern Japonica Rice Cultivation and Breeding Research Center, Shenyang Agricultural University,Shenyang, northeast China. Shennong 265 (typical erect panicle rice cultivar), and Liaojing 294 (traditional semi-erect panicle rice cultivar) were grown under different N rates to assess N uptake and N use efficiency. Nitrgen (N) uptake of two rice cultivars increased in their response to N improvement. Grain N of Liaojing 294 predominantly came from root absorption on low N treatments, while grain N of Shennong 265 mainly came from root absorption and had less N re-transferring from vegetative organs under high N rates. Shennong 265 produced less N uptake before heading and more N uptake after heading than Liaojing 294. GY was highly related with N fertilizer rate (r2 = 0.870** for Shennong 265, r2 = 0.613* for Liaojing 294). Shennong 265 was a N-unefficient genotype, since it produced low yield at low N levels and responded well to N application. Liaojing 294 was a N-efficient genotype producing high yield at both low and high N rates. NNG and NFUE exhibited positive correlation with N application rates, but NUEPG showed negative correlation with N application rates;GY as well as BIO and N uses efficiency parameters (TN, NNG, NFUE) which were all positively correlate, while the correlation between GY as well as BIO and the other N efficiency indicators expressed negative correlation. The relationship between GY and TN as well as BIO and TN was observed with significant difference (r2 = 0.824**, r2 = -0.858**).展开更多
基金supported by the Fundamental Research Funds for Central Public Welfare Research Institute,No.2020CZ-5(to WS and GS)the National Natural Science Foundation of China,No.31970970(to JSR)Fundamental Research Funds for the Central Universities,No.YWF-23-YG-QB-010(to JSR)。
文摘Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.
文摘The field experiment was conducted in 2005 and 2006 at Northern Japonica Rice Cultivation and Breeding Research Center, Shenyang Agricultural University,Shenyang, northeast China. Shennong 265 (typical erect panicle rice cultivar), and Liaojing 294 (traditional semi-erect panicle rice cultivar) were grown under different N rates to assess N uptake and N use efficiency. Nitrgen (N) uptake of two rice cultivars increased in their response to N improvement. Grain N of Liaojing 294 predominantly came from root absorption on low N treatments, while grain N of Shennong 265 mainly came from root absorption and had less N re-transferring from vegetative organs under high N rates. Shennong 265 produced less N uptake before heading and more N uptake after heading than Liaojing 294. GY was highly related with N fertilizer rate (r2 = 0.870** for Shennong 265, r2 = 0.613* for Liaojing 294). Shennong 265 was a N-unefficient genotype, since it produced low yield at low N levels and responded well to N application. Liaojing 294 was a N-efficient genotype producing high yield at both low and high N rates. NNG and NFUE exhibited positive correlation with N application rates, but NUEPG showed negative correlation with N application rates;GY as well as BIO and N uses efficiency parameters (TN, NNG, NFUE) which were all positively correlate, while the correlation between GY as well as BIO and the other N efficiency indicators expressed negative correlation. The relationship between GY and TN as well as BIO and TN was observed with significant difference (r2 = 0.824**, r2 = -0.858**).