Total Movement Time Research Articles

Effectiveness of an object moving depending on its orientation in the environment: a kinematic analysis of motor planning and execution

Background. Grasping objects with the hand is one of the most common movements in everyday life. It requires training involving the cognitive processes of goal selection and motor planning.Aim. To investigate the effect of object rotation on motor planning using an experiment where participants moved abstract objects that sometimes required rotation, and movement was assessed using a kinematic analysis system. We hypothesized that reaction times and movements would be longer for tasks with rotation.Materials and methods. Sixteen subjects participated in the study (11 females and 5 males), mean age – 23.375 ± 2.277 years. Participants were required to perform a task of moving 4 abstract objects onto corresponding platforms with their right hand, while periodically rotating the object by 90°, 180°, or 270°. The motion tracking system monitored the movement of trackers located on the subject’s right thumb and index finger, on the subject’s right wrist, and on the object and the subject’s special glasses.Results. To assess the effect of object rotation on motor planning, the data were grouped according to the angle of rotation. A one-factor analysis of variance with repeated measures was used. The results showed statistically significant differences:total movement time as a function of turning angle: F(3.45) = 5.014, p = 0.004;time to reach the grasping target: F(3.45) = 61.79, p = 0.001;object motion time: F(3.45) = 14.641, p = 0.001;time to reach maximum capture aperture: F(3.45) = 8.559, p = 0.001.Conclusion. Overall, our results support the hypothesis that object rotation during movement affects both the preparation and execution of the movement itself. The planning and executing the movement with the object rotated 180° was easier and faster than with 90° and 270° rotations. The testing allows distinguishing the stages of planning and preparation of the movement from the execution of the movement itself. Using this approach in patients with central nervous system lesions helps to assess and monitor the state of motor function, which is important for monitoring the recovery process.

Immediate Effect of Physiotherapist-demonstrated Action Observation with Execution for Improving Upper Extremity Motor Function in Stroke: a Pre-post Pilot Study.

Video-demonstrated action-observation-execution is an effective intervention for motor re-learning in stroke rehabilitation. But customization of video for each task repeatedly questions its feasibility within limited resources, particularly for daily routine practice and in community settings. Physiotherapist-demonstrated action-observation-execution is a practical intervention based on the principle of observation and consecutive repetitions of observed real, live movements. The main objective of this study was to investigate the immediate effect of Physiotherapist-demonstrated action-observation-execution in upper extremity motor training in stroke. Individuals with stroke were screened and 5 eligible participants were recruited. The research was a pre-post. A single session of Physiotherapist-demonstrated action-observation-execution was administered. A functional "Drinking" task was subdivided into simpler acts and trained. Pre and post intervention assessment of movement time using five hand-and-arm items of Nepali Wolf Motor Function Test were carried out. Global recovery was assessed in the form of Visual Analogue Scale. Paired t-test provided statistically significant difference in total movement time (mean difference=5.04 seconds, standard deviation=1.92, p=0.004) with larger effect size (0.95) indicating impressive improvement in movement time with the training. Substantial difference in global recovery score was noted (mean difference=17.40, standard deviation=3.65, p<0.0001, effect size=1.00) signifying the increased confidence and improved performance of upper extremity post treatment. The findings indicated that Physiotherapist-demonstrated action-observation-execution could be a feasible intervention to train motor functions in participants with stroke. Large-scale studies are recommended to establish the effectiveness of the intervention.

Temporal and Spatial Accuracy of Reaching Movements do not Improve Off-line

Consolidation has been associated with performance gains without additional practice (i.e., off-line learning). However, the movement characteristics improving off-line remain poorly understood. To investigate this question, participants were trained to produce a sequence of planar reaching movements toward four different visual targets. The training session with feedback required them to learn the relative time of the movements, the total movement time and aim accurately at each target. The retention test was performed either 10-min or 24-h after. Results revealed that a 24-h consolidation interval did not result in better temporal or spatial accuracy. This finding suggests that off-line learning may be restricted to sequence production tasks in which the different segments must be regrouped (“chunked”) together to accelerate their execution.

Research on Development Characteristics and Landslide Dam Hazard Prediction of Zhuangfang Landslide in the Upper Reaches of the Nu River

The upper reaches of the Nu River have strong tectonic activities and broken rock mass structures, often causing landslide disasters. The Zhuangfang landslide has apparent signs of surface deformation, and there is a risk of further sliding and blocking of the river. Taking the Zhuangfang landslide as an example, this paper analyzes the development characteristics and stability through geological field surveys, a drone aerial survey, field drilling, and GEO5 geotechnical engineering software. Then through the indoor tests and RAMMS numerical simulation software, the parameters of the landslide are determined, and the risk of a landslide dam is analyzed. Our results demonstrated that the Zhuangfang landslide is a large-scale landslide with a volume of about 4.5 × 106 m3. The front edge of the landslide is seriously deformed and is in an under-stable state, with risks of sliding and river blockage. The numerical simulation results showed that the total movement time of the landslide was 130 s, and the landslide entered the Nu River at 55 s. However, the landslide does not completely block the river and cannot form a landslide dam. The study proposed a parameter inversion method to determine the landslide mass parameters based on RAMMS numerical simulation software. The related results of this study can provide a reference for the sustainable development of the ecological environment in the Nu River Basin.

Effect of Suanzaoren Decoction on expression of ionotropic glutamate receptors and synaptic plasticity in hippocampus of anxiety rats

This study investigated the effect of Suanzaoren Decoction on the expression of N-methyl-D-aspartate receptors(NMDAR) and α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptors(AMPAR) in the hippocampus and synaptic plasticity in rats with conditioned fear-induced anxiety. The effect of Suanzaoren Decoction on rat behaviors were evaluated through open field experiment, elevated plus maze experiment, and light/dark box experiment. Enzyme-linked immunosorbent assay(ELISA) was used to measure the levels of glutamate(Glu) and γ-aminobutyric acid(GABA) in the rat hippocampus. Real-time fluorescence quantitative PCR(qRT-PCR) and Western blot were employed to assess the gene and protein expression of ionotropic glutamate receptors in the hippocampal region. Transmission electron microscopy was utilized to observe the changes in the ultrastructure of synaptic neurons in the hippocampal region. Long-term potentiation(LTP) detection technique was employed to record the changes in population spike(PS) amplitude in the hippocampal region of mice in each group. The behavioral results showed that compared with the model group, the Suanzaoren Decoction group effectively increased the number of entries into open arms, time spent in open arms, percentage of time spent in open arms out of total movement time, number of entries into open arms out of total entries into both arms(P&lt;0.01), and significantly increased the time spent in the light box and the number of shuttle crossings(P&lt;0.01). There was an increasing trend in the number of grid crossings, entries into the center grid, and time spent in the center grid, indicating a significant anxiolytic effect. ELISA results showed that compared with the model group, the Suanzaoren Decoction group exhibited significantly reduced levels of Glu, Glu/GABA ratio(P&lt;0.01), and significantly increased levels of GABA(P&lt;0.01) in the rat hippocampus. Furthermore, Suanzaoren Decoction significantly decreased the gene and protein expression of NMDAR(GluN2B and GluN2A) and AMPAR(GluA1 and GluA2) compared with the model group. Transmission electron microscopy results demonstrated improvements in synapses, neuronal cells, and organelles in the hippocampal region of the Suanzaoren Decoction group compared with the model group. LTP detection results showed a significant increase in the PS amplitude changes in the hippocampal region of Suanzaoren Decoction group from 5 to 35 min compared with the model group(P&lt;0.05, P&lt;0.01). In conclusion, Suanzaoren Decoction exhibits significant anxiolytic effects, which may be attributed to the reduction in NMDAR and AMPAR expression levels and the improvement of synaptic plasticity.

Roles of miR-196a and miR-196b in Zebrafish Motor Function.

The exertion of motor function depends on various tissues, such as bones and muscles. miR-196 has been widely studied in cancer and other fields, but its effect on bone and skeletal muscle is rarely reported. In order to explore the role of miR-196 family in bone and skeletal muscle, we used the previously successfully constructed miR-196a-1 and miR-196b gene knockout zebrafish animal models for research. The behavioral trajectories of zebrafish from 4 days post-fertilization (dpf) to 7 dpf were detected to analyze the effect of miR-196a-1 and miR-196b on motor ability. Hematoxylin-eosin (HE) staining and transmission electron microscopy (TEM) were used to detect the dorsal muscle tissue of zebrafish. The bone tissue of zebrafish was detected by microcomputed tomography (micro-CT). Real-time PCR was used to detect the expression levels of related genes, including vcp, dpm1, acta1b, mylpfb, col1a1a, bmp8a, gdf6a, and fgfr3. The behavioral test showed that the total behavioral trajectory, movement time, and movement speed of zebrafish larvae were decreased in the miR-196a-1 and miR-196b gene knockout lines. Muscle tissue analysis showed that the structure of muscle fibers in the zebrafish lacking miR-196a-1 and miR-196b was abnormal and was characterized by vacuolar degeneration of muscle fibers, intranuclear migration, melanin deposition, and inflammatory cell infiltration. Bone CT examination revealed decreased bone mineral density and trabecular bone number. The real-time PCR results showed that the expression levels of vcp, dpm1, gdf6a, fgfr3, and col1a1a were decreased in the miR-196b gene knockout group. The expression levels of dpm1, acta1b, mylpfb, gdf6a, and col1a1a were decreased, and the expression level of fgfr3 was increased in the miR-196b gene knockout group compared with the wild-type group. miR-196a-1 and miR-196b play an important role in muscle fiber structure, bone mineral density, and bone trabecular quantity by affecting the expression of vcp, dpm1, acta1b, mylpfb, gdf6a, fgfr3, and col1a1a and then affect the function of the motor system.

Sex differences in kinematics and quadriceps activity for fast isokinetic knee extension

BACKGROUND: The quantitative recruitment of motor units depends on specific demands, including movement velocity. DNA microarrays differ according to sex, and these sex-related differences affect the fiber type composition. OBJECTIVE: The aim of this study is to demonstrate inter-sex differences in the isokinetic parameters, isokinetic phases, and muscle activities and to investigate the correlation between muscle activity and isokinetic data. METHODS: A total of 41 healthy adults (20 male, 21 female) performed concentric knee extension at angular velocities of 60∘/s, 180∘/s, and 240∘/s. The outcome measures consisted of the isokinetic peak moment (PM), normalized PM (PM/BW), total work, and power, alongside the acceleration, iso-speed and deceleration, sub-phases. Muscle activity was recorded from the rectus femoris, vastus lateralis, and vastus medialis using surface EMG. RESULTS: There were significant two-factor main effect and interaction between sex and angular velocity on the power of knee extension and isokinetic phase (p&lt; 0.05). As the velocity increased, the increase in power of males was greater than that of females. In contrast, with the increase in velocity, PM, PM/BW, and total work decreased, but no significant interaction was observed between velocity and sex. At high velocity, males showed higher acceleration ability than females. CONCLUSION: The sex-dependent responses to velocity were more affected by differences in total movement time than force production. Fast isokinetic exercise should consider the acceleration ability rather than the ability to produce force.

Influence of handrail height and knee joint support on sit-to-stand movement.

Handrail height and knee joint support both significantly influence sit-to-stand (STS) movement. However, research on the associations between handrail height, knee joint support, and their cumulative effect on STS kinematics and changes in plantar pressure distribution during STS under different handrail heights and knee joint support is still unclear. The main objective of this study was to examine the influence of handrail height and knee joint support on the kinematics and the distribution of plantar pressure in healthy adults during STS. Twenty-six healthy adult subjects aged 23 to 58 years participated in this experiment. The subjects carried out STS movement experiments under 7 conditions: 6 experimental conditions of 3 different heights of handrail, with and without knee joint support, and 1 control condition of standing up naturally. The motions of the markers were recorded using cameras operating at 60 Hz, and total movement time, the percentage of movement time of each phase, trunk tilt angle, joint angle, plantar pressure, and the time from hindfoot to forefoot peak pressure were analyzed and compared. Handrail height significantly influences the percentage of movement time at phase I (P = .015) and the maximum trunk tilt angle (P < .05), knee joint support significantly influences the maximum trunk tilt angle and ankle angle (P = .033), and handrail height and knee joint support have an interaction on the time from hindfoot to forefoot peak pressure (P < .001). Subjects' STS performance was improved with the use of assistant devices but showed particular improvement under the condition of with knee joint support when the handrail height was middle handrail.

Physical Behaviors and Their Association With Adiposity in Men and Women From a Low-Resourced African Setting.

We first explored the associations between physical behaviors and total and regional adiposity. Second, we examined how reallocating time in different physical behaviors was associated with total body fat mass in men and women from a low-income South African setting. This cross-sectional study included a sample of 692 participants (384 men and 308 women) aged 41-72 years. Physical behaviors were measured using integrated hip and thigh accelerometry to estimate total movement volume and time spent in sleeping, sitting/lying, standing, light physical activity, and moderate to vigorous physical activity (MVPA). Total body fat mass and regional adiposity were measured using dual-energy X-ray absorptiometry. The associations between total movement volume and measures of regional obesity were mediated by total body adiposity. In men, reallocating 30 minutes of sitting/lying to 30 minutes of MVPA was associated with 1.0% lower fat mass. In women, reallocation of 30 minutes of sitting/lying to MVPA and 30 minutes of standing to MVPA were associated with a 0.3% and 1.4% lower fat mass, respectively. Although the association between physical behaviors and fat mass differed between men and women, the overall public health message is similar; reallocating sedentary time to MVPA is associated with a reduction in fat mass in both men and women.

Physical behaviors and their association with type 2 diabetes mellitus risk markers in urban South African middle-aged adults: an isotemporal substitutionapproach

IntroductionTo examine the associations between physical behaviors and type 2 diabetes mellitus (T2DM) risk markers in middle-aged South African men and women.Research design and methodsThis cross-sectional study included middle-aged men...

Non-motorised Rehabilitation Device for Performance Assessment in Upper Limb Stroke Rehabilitation: A Pilot Study

Stroke patients with upper limb disability restricted to carry out their activities of daily living. The patient needs a motivation to recover from a stroke and the patient also needs to go through a rehabilitation process at the same time. The conventional rehabilitation process scoring systems are always subjective, lack reliability and relies heavily on the ability of the trained physiotherapist that providing only rough estimates on motor function. On the other hand, robot-based assessments are objective, repeatable, and could potentially reduce the assessment time. Therefore, a simple non-motorized device was developed as a tool to objectively assess hand function of stroke patients. This study was carried out to investigate the suitability of using thedeveloped device with stroke patient populations and to evaluate the performance of clinical scores prediction of the stroke patients. A total of five patients with upper limb disability following stroke consented to take part in this study. Twelve predictive variables were investigated, relating to the total movement time, velocity, strategy, accuracy, and smoothness from three robotic assessment modules which are Draw I, Draw Diamond and Draw Circle. The hardware for measuring elbow angle hasbeen developed to measurethe shoulder movement performedby patient during the assessment process. In addition to that, the shoulder movement calculation method has been proposed and validated.The findings indicatethat the performance of prediction for all assessment modules hasbeen increased after implementing the shoulder movement calculation. It is recommended this calculation method to be used in conjunction with kinematic variables to carry out the data acquisition process in the future for improvement of effectiveness and accuracy of the robotic assessment.

Artificial Intelligence in Agricultural Picking Robot Displacement Trajectory Tracking Control Algorithm

With the development and leap of artificial intelligence technology, more and more robots have penetrated into all walks of life. Today’s agriculture is changing in the direction of modernization and automation. On the one hand, because of rising labor costs, it cannot afford to consume a large amount of labor for agricultural operations. On the other hand, the population is growing rapidly, and traditional agricultural production, picking, and other links have been unable to keep pace with the development of the times. Therefore, it is very necessary to use artificial intelligence technology to transform traditional agriculture. The purpose of this paper is to use artificial intelligence technology to plan, track, and optimize the displacement trajectory of the agricultural picking robot, so as to improve the working efficiency of the picking robot. In this paper, the neural network, the D-H modeling method of the manipulator, and the forward and reverse motion of the manipulator are explained and analyzed, and based on the relevant algorithms of neural network, the manipulator is modeled, and then the, forward and reverse motion of the manipulator is analyzed in detail, and the digital model of the picking robot is constructed. Then, the angle and motion speed of each joint of the robot are analyzed to reduce the motion trajectory error caused by friction and other factors. Then, the simulation experiment of the displacement trajectory tracking control is carried out, and the linear trajectory motion and the arc trajectory motion are deeply analyzed, and the axis error is greatly reduced after 6 iterations. Finally, the displacement trajectory is optimized. The optimized total movement time is shortened by 6.84 seconds, which enables the picking robot to not only ensure work efficiency but also accurately complete the planned displacement trajectory. After continuous experiments on the algorithm model and the picking robot, the actual trajectory of the picking robot at 0.7 seconds can be expected. The trajectories are completely coincident, indicating that the neural network plays a very important role in the trajectory research of picking robots.

Characterizing the Thermal Demands and Mobility Performance During International Wheelchair Rugby Competition.

ObjectiveTo determine the thermoregulatory responses and mobility performance of wheelchair rugby (WCR) players during international competition.MethodsEleven male National Team WCR players volunteered for the study. Testing occurred during a four game series against international competition (temp 24.7 ± 0.7°C, relative humidity 50.1 ± 3.6%), with movement time (MT) and gastrointestinal temperature (Tgi) recorded continuously.ResultsThe mean maximal Tgi was 38.6 ± 0.6°C (37.9–39.7) and did not significantly differ among Low-Class, Mid-Class, and High-Class athletes (p > 0.05). Moreover, there was a strong and significant relationship between minutes (min) played per quarter of the game and change in Tgi (r = 0.36, p = 0.01). Athletes moved a total of 27:43 ± 9:40 min:seconds (s), spent a total of 15:02 ± 8.23 min:s in Zone 1 (53.5%), 8:19 ± 3:20 min:s in Zone 2 (31.7%), and 5:59 ± 1:51 min:s in Zone 3 (21.3%). There were no differences among classification in total movement time (p = 0.169) or for speed in Zone 1, Zone 2, or Zone 3 (p > 0.05). The relationship between peak forward speed and total movement time was strong (p = 0.021, r = 0.68).ConclusionThis study demonstrated that the time spent in absolute movement zones is not classification dependent, the change in core temperature is related to movement time per quarter. Furthermore, peak speeds obtained on-court were linked to overall movement time which suggests athletes should warm-up before going on court.

Physical Activity Behaviors of a Middle-Age South African Cohort as Determined by Integrated Hip and Thigh Accelerometry.

ABSTRACTPurposeDescriptive studies of objectively measured physical activity behaviors in African populations are rare. We developed a method of combining hip and thigh accelerometery signals to quantify and describe physical behaviors in middle-age South African men and women.MethodsWe integrated signals from two triaxial accelerometers worn simultaneously during free-living, in a subsample of the Middle-age Soweto Cohort (n = 794; mean (SD) age, 53.7 (6.3) yr). Acceleration time series from the accelerometers were combined and movement-related acceleration was derived using Euclidean Norm Minus One (in milligrams), to determine total movement volume (mean Euclidean Norm Minus One) and nonmovement time (<28 mg), light-intensity physical activity (LPA; 28–85 mg), and moderate- to vigorous-intensity physical activity (MVPA; >85 mg); thigh pitch angle and a sleep diary were used to divide nonmovement time (in minutes per day) into sleep, awake sitting/lying, and standing. Sociodemographic factors were self-reported, and weight and height were measured.ResultsMean (SD) wear time was 128 (48) h. Movement volume was 15.0 (6.5) mg for men and 12.2 (3.4) mg for women. Men spent more time in MVPA and sitting/lying, whereas women spent more time standing. Age was inversely associated with movement volume, MVPA, and LPA. When compared with their normal-weight counterparts, men who were overweight or obese spent less time in MVPA, whereas women who were overweight or obese spent less time in LPA and more time sitting/lying. Socioeconomic status was inversely associated with total movement volume, MVPA, and time spent sleeping, and positively associated with time spent sitting/lying, in both men and women.ConclusionsIntegrating signals from hip and thigh accelerometers enables characterization of physical behaviors that can be applied in an African population.

Improvement of Airport Surface Operation at Tokyo International Airport Using Optimization Approach

Congestion and delays occur on airport surfaces as a result of a rapid increase in the demand for air transport. The aim of this study is to determine the differences between optimized and observed operations to improve airport surface operation at Tokyo International Airport by using mixed-integer linear programming to minimize the total ground movement distance and time based on real-time flight information. Receding horizon schemes are considered to adapt to dynamic environments. The model obtains results that reduce the taxi distance by 18.54% and taxi time by 29.77% compared with the observed data. A comparison of taxiway usage patterns between the optimization results and observed data provides insight into the optimization process, for example, changes in runway cross strategies and taxiway direction rules. Factors such as the objective function weights and airline–terminal relationship were found to significantly affect the optimization result. This study suggests improvements that can be made at airports to achieve a more efficient surface operation.

Kinematic Analysis of Daily Activity of Touching Lateral Shoulder for Normal Subjects

Analysis of motion is needed in order to gain a better understanding of upper-limb movements. Biomechanical studies involving measurements of movement analysis are very important so that upper-limb activities can be explained. The purpose of this study was to describe the temporal analysis for different age groups and investigate the relationship between kinematical analysis movements of upper-limb joints in the “touching contra lateral shoulder” activity with different age groups. The activity included hand lifting, resting and returning the hand to the initial position with twenty healthy subjects between 24 and 56 years old (n = 60). The Vicon motion analysis system, which consists of three infrared and high-speed cameras, was used to analyze several kinematical parameters such as movement times, peak velocities and joint angles of the shoulder, elbow and wrist. Descriptive kinematic variables were obtained, and phase definitions were determined. There were significant differences among all age groups for total movement times and angles of the shoulder, elbow and wrist joints. The quality of movement dropped after subjects reached an age of 50. Thus, the analysis that segmented this age group may provide relevant information that will help improve the understanding of the motor system with advancing age.

Effect of different handrail types and seat heights on kinematics and plantar pressure during STS in healthy young adults.

Handrail type and seat height both significantly influence sit-to-stand (STS) movement. However, research on the associations between handrail type, seat height, and their cumulative effect on STS kinematics and changes in plantar pressure distribution during STS under different handrail types and seat heights is insufficient.The main objective of this study was to investigate the effect of different handrail types and seat heights on the kinematics and plantar pressure in healthy adults during STS.The study was conducted on 26 healthy young adults. Six conditions were tested: low seat (LS) and vertical handrail; LS and horizontal handrail (HH); LS and bilateral handrail; high seat (HS) and vertical handrail; HSHH; HS and bilateral handrail. The movement time, trunk tilt angle, and time from hindfoot to forefoot peak pressure were analyzed and compared.A significant difference was found in handrail type (P < .001) and seat height (P < .02) for the total movement time of STS. A significant difference was also found for the maximum trunk tilt angles (P < .001) in handrail types. There was an interaction between handrail type and seat height for the time from hindfoot to forefoot peak pressure of STS (P = .003).Using HSHH could take less time to accomplish STS movement; it also reduced the maximum trunk tilt angle and thus reduce the risk of falling; the time from hindfoot to forefoot peak pressure when using HSHH was short and subjects could accomplish STS movement easier.

The influence of auditory rhythms on the speed of inferred motion.

The present research explored the influence of isochronous auditory rhythms on the timing of movement-related prediction in two experiments. In both experiments, participants observed a moving disc that was visible for a predetermined period before disappearing behind a small, medium, or large occluded area for the remainder of its movement. In Experiment 1, the disc was visible for 1 s. During this period, participants were exposed to either a fast or slow auditory rhythm, or they heard nothing. They were instructed to press a key to indicate when they believed the moving disc had reached a specified location on the other side of the occluded area. The procedure measured the (signed) error in participants' estimate of the time it would take for a moving object to contact a stationary one. The principal results of Experiment 1 were main effects of the rate of the auditory rhythm and of the size of the occlusion on participants' judgments. In Experiment 2, the period of visibility was varied with size of the occlusion area to keep the total movement time constant for all three levels of occlusion. The results replicated the main effect of rhythm found in Experiment 1 and showed a small, significant interaction, but indicated no main effect of occlusion size. Overall, the results indicate that exposure to fast isochronous auditory rhythms during an interval of inferred motion can influence the imagined rate of such motion and suggest a possible role of an internal rhythmicity in the maintenance of temporally accurate dynamic mental representations.

Task Oriented Training Activities Post Stroke Will Produce Measurable Alterations in Brain Plasticity Concurrent with Skill Improvement

ABSTRACT Background Task-oriented training with upper extremity (UE) skilled movements has been established as a method to regain function post stroke. Although improved UE function has been shown after this type of therapy, there is minimal evidence that brain plasticity is associated with this training. The accelerated skill acquisition program (ASAP) is an example of an approach for promoting UE function using targeting movements. Objective To investigate the effects of a single 2-hour session of ASAP in individuals with stroke on measures of brain plasticity as represented by corticospinal excitability (CE) and determine associations with reach-to-grasp (RTG) performance. Methods Eighteen post-acute stroke patients were randomized to two groups. Experimental group (n = 9) underwent ASAP for 2 hours, while the control group (n = 9) received dose equivalent usual and customary care. Both groups were evaluated for CE and RTG performance prior to the session and then four times after training: immediately, 1 day, 6 days, and 12 days. Results Significant alterations in CE were found in the peak-to-peak of Motor Evoked Potential amplitude of elbow and wrist extensor muscles in the lesioned hemisphere. The experimental group also demonstrated improved execution (shortened total movement time, TMT), feed-forward mechanism (deceleration time, DT) and planning (lengthened relative time to maximum hand aperture, RTApmax) compared to the control group Conclusion Alterations in brain plasticity occur concurrently with improvements in RTG performance in post-acute stroke patients with mild impairment after a single 2-hour session of task-oriented training and persist for at least 12 days.

Cumulative impacts of habitat fragmentation and the environmental factors affecting upstream migration in the threatened sea lamprey, Petromyzon marinus

Abstract River ecosystems are often fragmented by artificial structures, such as weirs. For anadromous species, these structures can impede access to upstream spawning sites and ultimately lead to severe population declines. This study focused on the freshwater spawning migration of the sea lamprey, Petromyzon marinus, an anadromous species threatened by habitat fragmentation across its native range. To quantify the cumulative impacts of multiple weirs on upstream‐migrating adults, and to explore the environmental factors affecting migratory movements, passive acoustic telemetry was applied to 56 individuals during their spawning migration in the heavily fragmented River Severn basin, UK. While 89% of tagged sea lamprey passed the first weir upstream of the release site on the main river, only 4% passed the fifth weir. For 85% of migrants, the upstream extent of migration was immediately downstream of a weir. Individuals that passed weirs upstream of the release site (n = 50) took 21.6 ± 2.8 days to reach their most upstream location, experiencing cumulative passage times at weirs of 15.7 ± 2.8 days; these delays constituted a median of 84% of total upstream movement times. Multistate models showed that the weir passage rates of sea lamprey in tidal and non‐tidal areas increased significantly when downstream river level and discharge were elevated. Upstream‐to‐downstream changes in direction were frequent downstream of weirs, but rare in unobstructed river sections. The results provided evidence for a cumulative effect of multiple weirs on sea lamprey movements, substantially delaying upstream migrants and limiting their spawning to atypical habitat. The results also demonstrated the crucial roles of high tides and elevated discharge events in enabling weir passage. Although the Severn Estuary features conservation designations for sea lamprey, this study reveals that barriers are inhibiting their upstream migration, a problem that should be addressed to assist sea lamprey conservation.