Passive activity enhances residual control ability in patients with complete spinal cord injury

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.

Integration of strategy, budgetary management and internal control system： A case of Sinochem Corporation

How budgetary management as a tool for planning and controlling of business operations is aligned with strategy and internal control system may not be problematic to American firms but is the most challengeable to large corporations in China. The case of Sinochem Corporation demonstrates the ways that budgetary management is linked with 3-year strategic planning at corporate level via yearly operating plans at business levels, and that budgets are integrated with internal control system into a device of task control to monitor whether business operations are on the track toward strategy. It is learned from the case that Chinese corporations have initiated different practices than American firms in solving the same issues.

Impact of Chronic Stress on Attention Control:Evidence from Behavioral and Event-Related Potential Analyses

Chronic stress affects brain function,so assessing its hazards is important for mental health.To overcome the limitations of behavioral data,we combined behavioral and event-related potentials(ERPs)in an attention network task.This task allowed us to differentiate between three specific aspects of attention:alerting,orienting,and execution.Forty-one participants under chronic stress and 31 non-stressed participants were enrolled.On the performance level,the chronically stressed group showed a significantly slower task response and lower accuracy.Concerning ERP measures,smaller cue-N1,cueN2,and larger cue-P3 amplitudes were found in the stressed group,indicating that this group was less able to assign attention to effective information,i.e.,they made inefficient use of cues and had difficulty in maintaining alerting.In addition,the stressed group showed larger target-N2 amplitudes,indicating that this group needed to allocate more cognitive resources to deal with the conflict targets task.Subgroup analysis revealed lower target-P3 amplitudes in the stressed than in the non-stressed group.Group differences associated with the attention networks were found at the ERP level.In the stressed group,excessive depletion of resources led to changes in attention control.In this study,we examined the effects of chronic stress on individual executive function from a neurological perspective.The results may benefit the development of interventions to improve executive function in chronically stressed individuals.

Sagittal SLIP-anchored task space control for a monopode robot traversing irregular terrain

As a well-explored template that captures the essential dynamical behaviors of legged locomotion on sagittal plane,the spring-loaded inverted pendulum(SLIP)model has been extensively employed in both biomechanical study and robotics research.Aiming at fully leveraging the merits of the SLIP model to generate the adaptive trajectories of the center of mass(CoM)with maneuverability,this study presents a novel two-layered sagittal SLIP-anchored(SSA)task space control for a monopode robot to deal with terrain irregularity.This work begins with an analytical investigation of sagittal SLIP dynamics by deriving an approximate solution with satisfactory apex prediction accuracy,and a two-layered SSA task space controller is subsequently developed for the monopode robot.The higher layer employs an analytical approximate representation of the sagittal SLIP model to form a deadbeat controller,which generates an adaptive reference trajectory for the CoM.The lower layer enforces the monopode robot to reproduce a generated CoM movement by using a task space controller to transfer the reference CoM commands into joint torques of the multi-degree of freedom monopode robot.Consequently,an adaptive hopping behavior is exhibited by the robot when traversing irregular terrain.Simulation results have demonstrated the effectiveness of the proposed method.