Motor Mechanisms Research Articles

Rotary mechanism of the prokaryotic Vo motor driven by proton motive force

ATP synthases play a crucial role in energy production by utilizing the proton motive force (pmf) across the membrane to rotate their membrane-embedded rotor c-ring, and thus driving ATP synthesis in the hydrophilic catalytic hexamer. However, the mechanism of how pmf converts into c-ring rotation remains unclear. This study presents a 2.8 Å cryo-EM structure of the Vo domain of V/A-ATPase from Thermus thermophilus, revealing precise orientations of glutamate (Glu) residues in the c12-ring. Three Glu residues face a water channel, with one forming a salt bridge with the Arginine in the stator (a/Arg). Molecular dynamics (MD) simulations show that protonation of specific Glu residues triggers unidirectional Brownian motion of the c12-ring towards ATP synthesis. When the key Glu remains unprotonated, the salt bridge persists, blocking rotation. These findings suggest that asymmetry in the protonation of c/Glu residues biases c12-ring movement, facilitating rotation and ATP synthesis.

Self-awareness from whole-body movements.

Humans can recognize their whole-body movements even when displayed as dynamic dot patterns. The sparse depiction of whole-body movements, coupled with a lack of visual experience watching ourselves in the world, has long implicated non-visual mechanisms to self-action recognition. We aimed to identify the neural systems for this ability. Using general linear modeling and multivariate analyses on human brain imaging data from male and female participants, we first found that cortical areas linked to motor processes, including frontoparietal and primary somatomotor cortices, exhibit greater engagement and functional connectivity when recognizing self-generated versus other-generated actions. Next, we show that these regions encode self-identity based on motor familiarity, even after regressing out idiosyncratic visual cues using multiple regression representational similarity analysis. Last, we found the reverse pattern for unfamiliar individuals: encoding localized to occipito-temporal visual regions. These findings suggest that self-awareness from actions emerges from the interplay of motor and visual processes.Significance Statement: We report for the first time that self-recognition from visual observation of our whole-body actions implicates brain regions associated with motor processes. On functional neuroimaging data, we found greater activity and unique representational patterns in brain areas and networks linked to motor processes when viewing our own actions relative to viewing the actions of others. These findings introduce an important role of motor mechanisms in distinguishing the self from others.

Interface-packing analysis of F1-ATPase using integral equation theory and manifold learning

It has been shown that the translational entropy of water plays a key role in biological processes such as protein folding and ligand binding. Under the physiological condition, tightly packed protein conformations like native structures are achieved so that the translational entropy of water is maximized. In this study, we investigate the rotation mechanism of a rotary protein motor, F1-ATPase, by analyzing the packing at the interfaces between the subunits. The packing at the interface between a subunit pair is analyzed using the change in the solvent entropy upon forming subunit pair, ∆S. It is found that as the γ subunit rotates, the ∆S value of a α-β subunit pair decrease because the interface packing becomes loose. However, because the interface packing of another α-β subunit pair becomes tighter upon the rotation, ∆S of this α-β subunit pair increases, leading to a compensation of the decrease in ∆S. Such compensation would be necessary to maximize the solvent entropy of F1-ATPase. In this study, packing at the interfaces between the subunits is also analyzed using a manifold-learning technique, and it is suggested a possibility that a qualitative estimation of the ∆S values of some α-β subunit pairs can be predicted using a manifold-learning technique.

Effect of load-resisting force on photoisomerization mechanism of a single second generation light-driven molecular rotary motor.

A pivotal aspect of molecular motors is their capability to generate load capacity from a single entity. However, few studies have directly characterized the load-resisting force of a single light-driven molecular motor. This research provides a simulation analysis of the load-resisting force for a highly efficient, second-generation molecular motor developed by Feringa et al. We investigate the M-to-P photoinduced nonadiabatic molecular dynamics of 9-(2,3-dihydro-2-methyl-1H-benz[e]inden-1-ylidene)-9H-fluorene utilizing Tully's surface hopping method at the semi-empirical OM2/MRCI level under varying load-resisting forces. The findings indicate that the quantum yield remains relatively stable under forces up to 0.003a.u., with the photoisomerization mechanism functioning typically. Beyond this threshold, the quantum yield declines, and an alternative photoisomerization mechanism emerges, characterized by an inversion of the central double bond's twisting direction. The photoisomerization process stalls when the force attains a critical value of 0.012a.u. Moreover, the average lifetime of the excited state oscillates around that of the unperturbed system. The quantum yield and mean lifetime of the S1 excited state in the absence of external force are recorded at 0.54 and 877.9fs, respectively. In addition, we analyze a time-dependent fluorescence radiation spectrum, confirming the presence of a dark state and significant vibrations, as previously observed experimentally by Conyard et al.

EEG sensorimotor rhythms dynamics in children with cerebral palsy during the course of neurorehabilitation, depending in the success of their imagination of movements

An analysis of changes in sensorimotor rhythms of the electroencephalogram (EEG) and features of the restoration of motor functions during a course of neurorehabilitation using a non-invasive brain-computer-hand exoskeleton interface was carried out in 50 children aged 7–15 years of both sexes suffering from cerebral palsy (CP). EEG was recorded in 32 leads under conditions of rest and kinesthetic imagination of hand extension movements. Depending on the success of the classifier program in determining imaginary states based on the EEG pattern, the children were divided into two groups – with high and low success when imagining movements. In children of the studied groups, when undergoing a course of neurorehabilitation, differences were revealed in the nature of changes in EEG amplitude in the sensorimotor mu (8–13 Hz) and beta (15–25 Hz) rhythms frequency ranges. When imagining movements of the right hand, intergroup differences for the mu rhythm reached the level of statistical significance in the medial electrodes of the fronto-central and parietal areas of the neocortex, for the beta rhythm – in the medial lead of the parietal region. Children in the group with high success showed a decrease or slight increase in the amplitude of the mu- and beta rhythm in these brain areas at the last session of the course compared to the first. We hypothesize that children in this group are not only better able to kinesthetically imagine movements throughout the course of neurorehabilitation, but also, based on feedback signals, learn to effectively adjust their strategies for movement imagination. Children in the group with low success showed an increase in the amplitude of sensorimotor rhythms in these brain areas, indicating the development of inhibition in the frontoparietal motor network. Patients, whose conditions were determined more accurately by the classifier, achieved higher rates of motor rehabilitation. The results of the study are important for clarifying the brain mechanisms of motor functions restoration in patients with cerebral palsy under the influence of a course of neurorehabilitation.

Evolutionary Cognitive Enhancement: Stimulating Whole-Body Problem-Solving Capacities

AbstractThis article argues that understanding the primary functions of cognitive processes in our evolutionary past can help to develop effective cognitive enhancement methods. The adaptive problems our ancestors faced forged interconnected cognitive and motor mechanisms supporting various movement-based problem-solving processes. However, the physical and social challenges these cognitive-motor capacities originally evolved to address are no longer prevalent in modern societies. Consequently, many adaptive problem-solving mechanisms linked to a wide range of body movements are often underused and insufficiently developed in modern contexts, contributing to age-related cognitive decline. From this view, and considering current cognitive enhancement techniques such as cognitive training, neurostimulation, physical exercise, and combined cognitive and physical training, the present article introduces an evolutionary-inspired cognitive enhancement framework. This framework advocates for developing strategies and training methods that stimulate our evolved cognitive-motor adaptations. In particular, therapeutic interventions should incorporate adaptive problems and whole-body movement solutions into modern technologies and computer-based tasks.

IoT based Smart Aquaculture Monitoring System for Fish Tank Management

Aquaculture, the farming of aquatic organisms, plays a critical role in meeting the increasing global demand for seafood. Effective monitoring and management of aquaculture systems are essential for ensuring optimal conditions and maximizing productivity. This research presents a comprehensive aquaculture-based fish tank monitoring system designed to enhance operational efficiency and fish welfare. At the heart of the system is the Arduino Uno microcontroller, serving as the central processing unit to coordinate various functions. Key components include pH sensor for continuous monitoring of acidity levels, turbidity sensor for detecting suspended particles, and water level sensor for maintaining optical water levels within the tank. In the event of abnormal pH levels or high turbidity, the system triggers automated alerts, sending notifications to the designated owner through SMS and transmitting data to an IoT website for remote monitoring. To ensure consistent environmental conditions, two pump motors are utilized: one for automatic water replenishment in case of water level fluctuations and another for removing water in case of particle accumulation. Furthermore, the system integrates a servo motor mechanism for precise dispensing of fish feed at predetermined intervals, promoting healthy growth and nutrition. Control over pump motors and feeding schedules is facilitated through a user-friendly website interface, providing operators with seamless management capabilities.

Motor, cognitive, and socio-cognitive mechanisms explaining social skills in autism and typical development.

Challenges in social functioning are considered a core criterion for diagnosing autism. Although motor skills, executive functioning (EF), and theory of mind (ToM) abilities independently affect social challenges and are interconnected, these abilities' shared contribution to the explanation of social functioning in autism remains under-investigated. To address this disparity, we examined the motor, EF, and ToM abilities of 148 autistic and non-autistic youth (ages 6-16 years), evaluating these variables' impact on social ability and their interconnections. Our mediation model exploring the contribution of motor, EF, and ToM skills explained 85% of the variance in social functioning (Social Responsiveness Scale-SRS-2). Analysis yielded a direct path from study group to SRS-2-social (typically developing-TD > autistic) and two main parallel indirect joint paths: (a) Group ➔ motor ➔ EF ➔ SRS-2-social; and (b) Group ➔ motor ➔ ToM ➔ SRS-2-social. In two secondary indirect paths, autistic children showed lower motor skills, which in turn explained their higher EF and/or ToM impairment, which in turn explained their higher social skills impairment. Put differently, our results suggest that better EF and TOM proficiency may compensate for poorer motor skills. Findings also indicated that the collective impact of motor, EF, and ToM skills on social functioning, along with the mediating role played by EF and ToM on the social-motor linkage, may contribute to understanding individual differences in the social functioning of autistic children. These conclusions call for the inclusion of motor, EF, and ToM activities into daily practices to facilitate social functioning.

Auditory Noise Facilitates Lower Visual Reaction Times in Humans.

Noise is commonly seen as a disturbance but can influence any system it interacts with. This influence may not always be desirable, but sometimes it can improve the system's performance. For example, stochastic resonance is a phenomenon where adding the right amount of noise to a weak signal makes it easier to detect. This is known as sub-threshold detection. This sub-threshold detection's natural fingerprint is the fact that the threshold values follow an inverse U-shaped curve as the noise intensity increases. The minimum threshold value is the point of maximum sensitivity and represents the optimal point that divides the dynamics in two. Below that point, we can find the beneficial noise branch, where the noise can facilitate better detection. Above that point, the common detrimental noise concept can be found: adding noise hinders signal detection. The nervous system controls the movements and bodily functions in the human body. By reducing the sensory thresholds, we can improve the balance of these functions. Additionally, researchers have wondered if noise could be applied to different senses or motor mechanisms to enhance our abilities. In this work, noise is used to improve human reaction times. We tested the hypothesis that visual reaction times decrease significantly when the subject's perception is in the beneficial noise branch and closer to the optimal point than outside of this condition. Auditory noise was introduced in 101 human subjects using an interface capable of searching for the right amount of noise to place the subject in the beneficial noise branch close to the optimal point. When comparing the results, the reaction times decreased when the subjects were at the optimal point compared to when the subjects were outside of such conditions. These results reveal the possibility of using this approach to enhance human performance in tasks requiring faster reaction times, such as sports.

Nanometer-resolution tracking of single cargo reveals dynein motor mechanisms.

Cytoplasmic dynein is essential for intracellular transport. Despite extensive in vitro characterizations, how the dynein motors transport vesicles by processive steps in live cells remains unclear. To dissect the molecular mechanisms of dynein, we develop optical probes that enable long-term single-particle tracking in live cells with high spatiotemporal resolution. We find that the number of active dynein motors transporting cargo switches stochastically between one and five dynein motors during long-range transport in neuronal axons. Our very bright optical probes allow the observation of individual molecular steps. Strikingly, these measurements reveal that the dwell times between steps are controlled by two temperature-dependent rate constants in which two ATP molecules are hydrolyzed sequentially during each dynein step. Thus, our observations uncover a previously unknown chemomechanical cycle of dynein-mediated cargo transport in living cells.

Sleep benefits perceptual but not movement-based learning of locomotor sequences

Practicing complex locomotor skills, such as those involving a step sequence engages distinct perceptual and motor mechanisms that support the recall of learning under new conditions (i.e., skill transfer). While sleep has been shown to enhance learning of sequences of fine movements (i.e., sleep-dependent consolidation), here we examined whether this benefit extends to learning of a locomotor pattern. Specifically, we tested the perceptual and motor learning of a locomotor sequence following sleep compared to wake. We hypothesized that post-practice sleep would increase locomotor sequence learning in the perceptual, but not in the motor domain. In this study, healthy young adult participants (n = 48; 18–33 years) practiced a step length sequence on a treadmill cued by visual stimuli displayed on a screen during training. Participants were then tested in a perceptual condition (backward walking with the same visual stimuli), or a motor condition (forward walking but with an inverted screen). Skill was assessed immediately, and again after a 12-h delay following overnight sleep or daytime wake (n = 12 for each interval/condition). Off-line learning improved following sleep compared to wake, but only for the perceptual condition. Our results suggest that perceptual and motor sequence learning are processed separately after locomotor training, and further points to a benefit of sleep that is rooted in the perceptual as opposed to the motor aspects of motor learning.

The Motoric and Cognitive Mechanisms of Evolving Dialectical Differences [Conference Presentation Abstract

The Motoric and Cognitive Mechanisms of Evolving Dialectical Differences [Conference Presentation Abstract

Smart Mobility and Sensor Based-BRT Crusade, the Challenge for Auto Mechanics and Technicians in Africa

African countries with no globally recognized auto manufacturing factories are flooded with the most modern automobiles as soon as they are commercialized in the absence of commensurate skilled local auto mechanics across the continent. In the wake of the Bus Rapid Transit (BRT) scheme in Abuja Nigeria, the first set of luxurious buses purchased ended up as junks within a short period of operation largely due to lack of technician competency. The continuous patronage of a few multinational workshop garages like Toyota, Honda, Kia Motors, etc is hindering the transport agencies from breaking even. This paper is therefore aimed at evaluating the state of bus auto-mechanics and technicians in Nigeria for sustainable hybrid buses for effective BRT in the country. Google search engine was used to source secondary data from dedicated transport and energy-related sites like National Research Council (NRC) Agora Verkehrswende and GIZ, Smart city study, USDoT, and Africa Transport Solution, for the current paradigm shift in automobile energy management. Participatory surveys were carried out in two major motor mechanic villages that house over two hundred (200) workshops. The study reveals that there is a yawning gap between the societal ideal auto-mechanic expectations and the operational woe realities. This work becomes very relevant in view of global urbanization and the crusade for Hybrid Bus Rapid Transit (HBRT) in urban mobility as a panacea to COP28 carbon emission reduction. It is recommended that policymakers in urban transportation at all levels should ensure the certification and re-training of the motor mechanics to be able to maintain those imported modern buses while investing in ITS-based road infrastructure for sustainable BRT in their country

An IoT based Low-cost Artificial Mechanical Ventilator for Patients

This paper presents the construction of a low-cost, open-source mechanical ventilator. The motto behind making this type of ventilator comes from the global shortage of ventilators to treat patients suffering with Covid-19. This paper presents a digital method to monitor the lung status of patients. This is achieved by determining pressure measurements from the inspiratory arm and alerts clinicians if the patient is in a healthy or unhealthy condition. The common symptoms of Covid-19 that can be easily identified are body temperature, blood oxygen level and heart rate that we must check to identify the virus. Hence this system can help in case a patient is unable to meet the doctor or requires frequent monitoring. These are going to develop a system which can monitor, and all the monitored data is stored in the cloud. When people suffer from breathing problems, this can be used for emergencies. The ventilator will be able to monitor the patient's blood oxygen levels and exhaled lung pressure while avoiding high pressure. Designed using Arduino, the ventilator meets all these requirements, creating an affordable ventilator to help during a pandemic. A motor mechanism is used to push the air bag. When the oxygen level counts are low, this mechanism is utilized. LCD screens are used to display oxygen levels. Whenever a patient faces a dangerous position, a buzzer sounds to notify a nearby caretaker. The entire system is driven by an Arduino microcontroller and a buzzer is fitted to detect any low levels of oxygen count. Index Terms: Oxygen, Covid-19, Ventilator, Lung pressure, Air bag.

Sustainable effectiveness of kinetic chain stretching on active hip flexion movement and muscle activation for hamstring tightness: A preliminary investigation.

Conventional hamstring (HAM) stretching therapeutic effects are not substantiable in neuromusculoskeletal conditions with HAM tightness or shortness. We developed a kinetic chain stabilization exercise to provide a more sustainable effectiveness in adults with HAM tightness. However, its therapeutic effects and underlying motor mechanisms remain unknown. To compare the effects of traditional active HAM stretching (AHS) and kinetic chain stretching (KCS) on electromyographic (EMG) amplitude and hip flexion range of motion (ROM) in participants with HAM tightness. In this randomized controlled trial, 18 participants (mean age: 25.01 ± 2.47 years) with HAM tightness were assigned to the AHS or KCS group. Hip joint movement, EMG amplitude, and onset times were recorded in the bilateral erector spinae, HAM, transverse abdominis/internal oblique (IO), external oblique (EO), and rectus abdominis during a straight leg raise test. Compared to AHS, KCS led to greater increase in the hip flexion ROM and EMG activation amplitudes in the left and right EO and left IO. Post-test hip flexion ROM data in both the groups were higher than the pre-test data. KCS produced more sustainable effectiveness in hip flexion movement and EMG motor control patterns in participants with HAM tightness than AHS.

The Effect of 3D Computer Animated-Content Coaching Style on Student Academic Feat in Motor Vehicle Mechanics Work in Technical Colleges

The impacting of knowledge/skills in the technical college in the recent time in the modern world is by coaching students with 3D computer animated-content in the Western world. The usage of the 3D computer animated-content, makes coaching to be real to students, they see and feel the objects which they use to learn. Eighty-one (81) students was deployed for the probe, sampling of students was not done because of the population that was deployed for the probe, all the students that offers motor vehicle mechanics work in the selected technical colleges were deployed for the probe. The apparatus that was deployed for the probe was motor vehicles mechanics work feat test, was validated using fifteen students from practical college in Anambra State. Three lecturers were deployed for the validation, after the validation a reliability test was conducted and it was detected that the reliability of the apparatus was 0.73, meaning that the apparatus was reliable. Two probe question were raised to guide the probe and two hypotheses were formulated at 0.05 level of implication, to check for level of implication using (ANCOVA) to check the level of implication. Findings were made, and conclusion was also made by the investigator at the end of the probe.

Stability control of single-wheel failure in four-wheel independent drive electric vehicles

The integration of the motor and transmission mechanism into the wheels of a four-wheel independent drive electric vehicle with hub motors increases the frequency of failures, especially torque output failures, which seriously affect vehicle stability and jeopardize driving safety. This paper focuses on the perspective of single-wheel torque output failure and studies the vehicle stability control strategy. Firstly, based on the constructed simulation dynamics model, a slip controller is designed to obtain the direct lateral moment. Then, based on the control allocation principle, upper-level lateral moment allocation rules are designed, and torque allocation rules under single-wheel torque output failure are formulated. Finally, simulation experiments are conducted under different operating conditions. The simulation results show that this control strategy can effectively control vehicle stability under single-wheel failure conditions and ensure safe driving.

Advanced neuroimaging techniques to explore the effects of motor and cognitive rehabilitation in multiple sclerosis.

Progress in magnetic resonance imaging (MRI) technology and analyses is improving our comprehension of multiple sclerosis (MS) pathophysiology. These advancements, which enable the evaluation of atrophy, microstructural tissue abnormalities, and functional plasticity, are broadening our insights into the effectiveness and working mechanisms of motor and cognitive rehabilitative treatments. This narrative review with selected studies discusses findings derived from the application of advanced MRI techniques to evaluate structural and functional neuroplasticity modifications underlying the effects of motor and cognitive rehabilitative treatments in people with MS (PwMS). Current applications as outcome measure in longitudinal trials and observational studies, their interpretation and possible pitfalls and limitations in their use are covered. Finally, we examine how the use of these techniques could evolve in the future to improve monitoring of motor and cognitive rehabilitative treatments. Despite substantial variability in study design and participant characteristics in rehabilitative studies for PwMS, improvements in motor and cognitive functions accompanied by structural and functional brain modifications induced by rehabilitation can be observed. However, significant enhancements to refine rehabilitation strategies are needed. Future studies in this field should strive to implement standardized methodologies regarding MRI acquisition and processing, possibly integrating multimodal measures. This will help identifying relevant markers of treatment response in PwMS, thus improving the use of rehabilitative interventions at individual level. The combination of motor and cognitive strategies, longer periods of treatment, as well as adequate follow-up assessments will contribute to enhance the quality of evidence in support of their routine use.

Biomechanics of alpine skiing and the forces that affect it

The result in alpine skiing depends on the interaction of the athlete’s body and equipment with the snow. Therefore, to get the best results, you need to use the equipment in such a way as to get the necessary reaction from the snow, because turns and braking occur due to the impact of snow on the skis. At the same time, the athlete must constantly remain in balance to avoid falls. Therefore, the aim of the study was to investigate the biomechanical apparatus of an alpine skier and the main forces that act on him during the passage of the track. To achieve this goal, the method of theoretical analysis and generalization of scientific and methodological literature was used. This paper provides a comprehensive analysis of the motor aspects and mechanics that affect athletes in alpine skiing. The article discusses the biomechanics of alpine skiing, its features and the main forces that act on an athlete while overcoming a ski slope. The article also discusses some specific terminology of skiing, which is closely related to the biomechanics of motor actions and the impact of physical forces on the athlete. Another crucial aspect of success in skiing is feeling. This article discusses the problem of using the information of sensations in skiers, obtained through musculo-articular channels and tactile senses of the athlete, the sense of time to assess the quality of downhill control. The study is important for training and preparation of athletes, where the analysis of biomechanics of movements allows to optimize the skiing technique and minimize the risk of injury. Understanding of these aspects helps to improve training strategies and develop more effective methods for improving skiing skills. The results of the research can contribute to the improvement of technique in amateur skiing, the improvement of technical training of athletes and the development of more effective training methods for achieving success in alpine skiing.

The language network as a natural kind within the broader landscape of the human brain.

Language behaviour is complex, but neuroscientific evidence disentangles it into distinct components supported by dedicated brain areas or networks. In this Review, we describe the 'core' language network, which includes left-hemisphere frontal and temporal areas, and show that it is strongly interconnected, independent ofinput and output modalities, causally important for language and language-selective. We discuss evidence that this language network plausibly stores language knowledge and supports core linguistic computations related to accessing words and constructions from memory and combining them to interpret (decode) or generate (encode) linguistic messages. We emphasize that the language network works closely with, but is distinct from, both lower-level - perceptual and motor - mechanisms and higher-level systems of knowledge and reasoning. The perceptual and motor mechanisms process linguistic signals, but, in contrast to the language network, are sensitive onlyto these signals' surface properties, not their meanings; the systems of knowledge and reasoning (such as the system that supports social reasoning) are sometimes engaged during language use but are not language-selective. This Review lays a foundation both for in-depth investigations of these different components of the language processing pipeline and for probing inter-component interactions.