SISTEMA DE ACIONAMENTO EMBARCADO DE MOTORES CC DO VEÍCULO ELÉTRICO DA FAESA

The present work aimed at researching, sizing and monitoring of FAESA's electric vehicle prototype propulsion system, with the aid of sensors and a low-cost microcontroller. The prototype was incomplete and required electrical resizing and mechanical adjustments. From an Arduino it was possible to perform both the motor activation and measurement of the current and speed sensors.

Human Premotor Corticospinal Projections Are Engaged in Motor Preparation at Discrete Time Intervals: A TMS-Induced Virtual Lesion Study

Objectives: The significance of pre-motor (PMC) corticospinal projections in a frontoparietal motor network remains elusive. Temporal activation patterns can provide valuable information about a region's engagement in a hierarchical network. Navigated transcranial magnetic stimulation (nTMS)-induced virtual lesions provide an excellent method to study cortical physiology by disrupting ongoing activity at high temporal resolution and anatomical precision. We use nTMS-induced virtual lesions applied during an established behavioral task demanding pre-motor activation to clarify the temporal activation pattern of pre-motor corticospinal projections.Materials and Methods: Ten healthy volunteers participated in the experiment (4 female, mean age 24 ± 2 years, 1 left-handed). NTMS was used to map Brodmann areae 4 and 6 for primary motor (M1) and PMC corticospinal projections. We then determined the stimulator output intensity required to elicit a 1 mV motor evoked potential (1 mV-MT) through M1 nTMS. TMS pulse were randomly delivered at distinct time intervals (40, 60, 80, 100, 120, and 140 ms) at 1 mV-MT intensity to M1, PMC and the DLPFC (dorsolateral pre-frontal cortex; control condition) before participants had to perform major changes of their trajectory of movement during a tracing task. Each participant performed six trials (20 runs per trial). Task performance and contribution of regions under investigation was quantified through calculating the tracing error induced by the stimulation.Results: A pre-motor stimulation hotspot could be identified in all participants (16.3 ± 1.7 mm medial, 18.6 ± 1.4 mm anterior to the M1 hotspot). NTMS over studied regions significantly affected task performance at discrete time intervals (F(10, 80) = 3.25, p = 0.001). NTMS applied over PMC 120 and 140 ms before changes in movement trajectory impaired task performance significantly more than when applied over M1 (p = 0.021 and p = 0.003) or DLPFC (p = 0.017 and p < 0.001). Stimulation intensity did not account for error size (β = −0.0074, p = 1).Conclusions: We provide novel evidence that the role of pre-motor corticospinal projections extends beyond that of simple corticospinal motor output. Their activation is crucial for task performance early in the stage of motor preparation suggesting a significant role in shaping voluntary movement. Temporal patterns of human pre-motor activation are similar to that observed in intracortical electrophysiological studies in primates.

Dynein activation in vivo is regulated by the nucleotide states of its AAA3 domain

SummaryCytoplasmic dynein is activated by dynactin and cargo adapters in vitro, and the activation also needs LIS1 (Lissencephaly 1) in vivo. How this process is regulated remains unclear. Here we found in Aspergillus nidulans that a dynein AAA4 arginine-finger mutation bypasses the requirement of LIS1 for dynein activation driven by the early endosomal adapter HookA. As the AAA4 arginine-finger is implicated in AAA3 ATP hydrolysis, we examined AAA3 mutants defective in ATP binding and hydrolysis respectively. Astonishingly, blocking AAA3 ATP hydrolysis allows dynein activation by dynactin in the absence of LIS1 or HookA. As a consequence, dynein accumulates at microtubule minus ends while early endosomes stay near the plus ends. On the other hand, blocking AAA3 ATP binding abnormally prevents LIS1 from being dissociated from dynein upon motor activation. Thus, the AAA3 ATPase cycle regulates the coordination between dynein activation and cargo binding as well as the dynamic dynein-LIS1 interaction.

Single-molecule imaging of cytoplasmic dynein reveals the mechanism of motor activation and cargo capture

Cytoplasmic dynein 1 (dynein) is the primary minus end-directed motor protein in most eukaryotic cells (1). Dynein remains in an inactive conformation until the formation of a tripartite complex comprising dynein, its regulator dynactin and a cargo adaptor (2-5). Thereupon, dynein transports cargo towards the minus ends of microtubules. How this process of motor activation occurs is unclear, since it entails the formation of a three-protein complex inside the crowded environs of a cell. Here, we employed live-cell, single-molecule imaging to visualise and track fluorescently tagged dynein. First, we observed that dynein that bound to the microtubule engaged in minus end-directed movement only ~30% of the time and resided on the microtubule for a short duration. Next, using high-resolution imaging in live and fixed cells, we discovered that dynactin remained persistently attached to microtubules, and endosomal cargo remained in proximity to the microtubules and dynactin. Finally, we employed two-colour imaging to visualise cargo movement effected by single motor binding. Taken together, we discovered a search strategy that is facilitated by dynein's frequent microtubule binding-unbinding kinetics: (1) in a futile event when dynein does not encounter cargo anchored in proximity to the microtubule, dynein unbinds and diffuses into the cytoplasm, (2) when dynein encounters cargo and dynactin upon microtubule binding, it moves cargo in a short run. In conclusion, we demonstrate that dynein activation and cargo capture are coupled in a step that relies on reduction of dimensionality to enable minus end-directed transport in vivo.

Physical fitness percentiles of Polish children aged 4–7 years

The purpose of this study was to report sex- and age-specific physical fitness level in Polish children aged 4 to 7. 11.709 children participated in the study, including 5.684 girls and 6.025 boys aged 4 to 7 who attended kindergarten institutions throughout Poland. Physical fitness was assessed using four tests developed by Sekita including shuttle run 4 × 5 m with moving the block, standing long jump, throwing 1 kg medicine ball with two hands above the head and 20 m run. Percentile charts were developed separately for males and females using the LMS method. Boys showed higher physical fitness values than girls. In addition, an increase in the level of physical fitness was observed along with the age of the subjects. The developed reference values by age and sex in the field of physical fitness can be used for diagnostic purposes and assessing the level of physical fitness of preschool children. In addition, they can be helpful for healthcare professionals, parents and teachers to develop children’s motor activation programs and monitor their physical fitness.

Alterations of Spinal Epidural Stimulation-Enabled Stepping by Descending Intentional Motor Commands and Proprioceptive Inputs in Humans With Spinal Cord Injury

Background: Regaining control of movement following a spinal cord injury (SCI) requires utilization and/or functional reorganization of residual descending, and likely ascending, supraspinal sensorimotor pathways, which may be facilitated via task-specific training through body weight supported treadmill (BWST) training. Recently, epidural electrical stimulation (ES) combined with task-specific training demonstrated independence of standing and stepping functions in individuals with clinically complete SCI. The restoration of these functions may be dependent upon variables such as manipulation of proprioceptive input, ES parameter adjustments, and participant intent during step training. However, the impact of each variable on the degree of independence achieved during BWST stepping remains unknown.Objective: To describe the effects of descending intentional commands and proprioceptive inputs, specifically body weight support (BWS), on lower extremity motor activity and vertical ground reaction forces (vGRF) during ES-enabled BWST stepping in humans with chronic sensorimotor complete SCI. Furthermore, we describe perceived changes in the level of assistance provided by clinicians when intent and BWS are modified.Methods: Two individuals with chronic, mid thoracic, clinically complete SCI, enrolled in an IRB and FDA (IDE G150167) approved clinical trial. A 16-contact electrode array was implanted in the epidural space between the T11-L1 vertebral regions. Lower extremity motor output and vertical ground reaction forces were obtained during clinician-assisted ES-enabled treadmill stepping with BWS. Consecutive steps were achieved during various experimentally-controlled conditions, including intentional participation and varied BWS (60% and 20%) while ES parameters remain unchanged.Results: During ES-enabled BWST stepping, the knee extensors exhibited an increase in motor activation during trials in which stepping was passive compared to active or during trials in which 60% BWS was provided compared to 20% BWS. As a result of this increased motor activation, perceived clinician assistance increased during the transition from stance to swing. Intentional participation and 20% BWS resulted in timely and purposeful activation of the lower extremities muscles, which improved independence and decreased clinician assistance.Conclusion: Maximizing participant intention and optimizing proprioceptive inputs through BWS during ES-enabled BWST stepping may facilitate greater independence during BWST stepping for individuals with clinically complete SCI.Clinical Trial Registration:ClinicalTrials.gov identifier: NCT02592668.

Does the Activation of Motor Information Affect Semantic Processing?

Several behavioral studies show that semantic content influences reach-to-grasp movement responses. However, not much is known about the influence of motor activation on semantic processing. The present study aimed at filling this gap by examining the influence of pre-activated motor information on a subsequent lexical decision task. Participants were instructed to observe a prime object (e.g., the image of a frying pan) and then judge whether the following target was a known word in the lexicon or not. They were required to make a keypress response to target words describing properties either relevant (e.g., handle) or irrelevant (e.g., ceramic) for action or unrelated to the prime object (e.g., eyelash). Response key could be located on the same side as the depicted action-relevant property of the prime object (i.e., spatially compatible key) or on the opposite side (i.e., spatially incompatible key). Results showed a facilitation in terms of lower percentage errors when the target word was action-relevant (e.g., handle) and there was spatial compatibility between the orientation of the action-relevant component of the prime object and the response. This preliminary finding suggests that the activation of motor information may affect semantic processing. We discuss implications of these results for current theories of action knowledge representation.

Optimization of Physiological Processes in Conditions Staged Activation of Motor Activity in Cardiac Patients

The development of coronary atherosclerosis leads to the formation of coronary heart disease, which threatens early death or disability. Such patients need a shunt operation to restore blood flow in the vessels of the heart. After this operation, patients need complex rehabilitation, which has strict stages. To expand the physical activity of patients after coronary bypass grafting, a system of motor activity consisting of 7 steps is used, modified for use in Russian clinical conditions for the rehabilitation of patients after shunting of blood vessels supplying the myocardium. This technique involves the use of seven stages of motor activation of patients, through the use of complexes of medical-physical culture with a gradual strengthening of gymnastic exercises, through the use of training using exercise bikes and dosed walking in open areas, built on the principle of "from simple to more complex." The first two stages of motor activation are applicable to patients immediately after coronary artery bypass grafting at the stationary stage; 3-5 stages of motor activation are physiologically justified for in-patient rehabilitation; the 6-7 steps of motor activation are applicable to patients on outpatient rehabilitation.