Walking representation and simulation based on multi-source image fusion and multi-agent reinforcement learning for gait rehabilitation.

In the formulation of strategies for walking rehabilitation, achieving precise identification of the current state and making rational predictions about the future state are crucial but often unrealized. To tackle this challenge, our study introduces a unified framework that integrates a novel 3D walking motion capture method using multi-source image fusion and a walking rehabilitation simulation approach based on multi-agent reinforcement learning. We found that, (i) the proposal achieved an accurate 3D walking motion capture and outperforms other advanced methods. Experimental evidence indicates that, compared to similar visual skeleton tracking methods, the proposed approach yields results with higher Pearson correlation (r=0.93), intra-class correlation coefficient (ICC(2,1)=0.91), and narrower confidence intervals ([0.90,0.95] for r, [0.88,0.94] for ICC(2,1)) when compared to standard results. The outcomes of the proposed approach also exhibit commendable correlation and concurrence with those obtained through the IMU-based skeleton tracking method in the assessment of gait parameters ([0.85,0.89] for r, [0.75,0.81] for ICC(2,1)); (ii) multi-agent reinforcement learning has the potential to be used to solve the simulation task of gait rehabilitation. In mimicry experiment, our proposed simulation method for gait rehabilitation not only enables the intelligent agent to converge from the initial state to the target state, but also observes evolutionary patterns similar to those observed in clinical practice through motor state resolution. This study offers valuable contributions to walking rehabilitation, enabling precise assessment and simulation-based interventions, with potential implications for clinical practice and patient outcomes.

Meta-Analysis of Duplex Surveillance Following Lower Limb Endovascular Intervention.

INTRODUCTION: The aim of this systematic review was to identify the evidence in the literature for limb salvage with the introduction of duplex surveillance. METHODS: A systematic review and meta-analysis was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines (PRISMA) methodology for all studies which compared a group undergoing clinical surveillance with a group undergoing combined clinical and duplex surveillance after endovascular therapy for peripheral arterial disease. MEDLINE, EMBASE, the Cochrane Database for Systematic Reviews, and ClinicalTrials.gov were searched for relevant studies by 2 reviewers. Studies were quality assessed using the ROBINS-I tool. An individual patient data survival analysis and meta-analysis for 1- and 2-year amputation outcomes using a random-effects model were performed. RESULTS: Two low-quality nonrandomized studies met the inclusion criteria. There was a statistically and clinically significant reduction in major amputation in patients undergoing combined clinical and duplex surveillance (log-rank p<0.001). The number needed to treat to prevent 1 amputation at 2 years was 5 patients. At 1 year, the odds ratio (OR) for amputation was 0.22, 95% confidence interval (CI)=0.10-0.48, with no statistical heterogeneity. At 2 years, the numbers of patients were low and the effect on amputation was less certain OR=0.25, 95% CI=0.04-1.58. CONCLUSIONS: Preliminary, low-quality data suggests that there may be a clinically significant reduction in major amputation with the introduction of duplex surveillance. It is recommended that a randomized controlled trial is performed to confirm these findings and identify the anatomical subgroups that benefit the most from surveillance. CLINICAL IMPACT: "Two low-quality studies reveal a significant clinical impact: combined clinical and duplex surveillance markedly reduces major amputations (log-rank p<0.001). At 1-year, the odds ratio for amputation is 0.22 (95% CI=0.10-0.48), emphasizing limb salvage benefits. Despite less certainty at 2-years, a notable absolute risk reduction of 19% is seen, with a number needed to treat of 5. This underscores the urgent need for a randomized controlled trial to validate findings and identify key subgroups. The meta-analysis strongly advocates implementing duplex surveillance for a year post-endovascular interventions, especially in patients fit for reintervention, with important considerations for cost-effectiveness and focused clinical trials."

The effects of lower limb ischaemic preconditioning: a systematic review.

Ischaemic preconditioning (IPC) involves the use of repeated occlusions and reperfusions of the peripheral muscle blood supply at a limb. This systematic literature review examines the typical responses in response to the method of application during an IPC applied at the lower limb. This review focuses on the physiological responses for VO2max, haemoglobin, metabolic and genetic responses to various IPC interventions. The literature search was performed using four databases and assessed using the PRISMA search strategy and COSMIN to assess the quality of the articles. Seventeen articles were included in the review, with a total of 237 participants. While there is variation in the method of application, the average occlusion pressure was 222 ± 34 mmHg, ranging from 170 to 300 mmHg typically for 3 or 4 occlusion cycles. The distribution of this pressure is influenced by cuff width, although 8 studies failed to report cuff width. The majority of studies applies IPC at the proximal thigh with 16/17 studies applying an occlusion below this location. The results highlighted the disparities and conflicting findings in response to various IPC methods. While there is some agreement in certain aspects of the IPC manoeuvre such as the location of the occlusion during lower limb IPC, there is a lack of consensus in the optimal protocol to elicit the desired responses. This offers the opportunity for future research to refine the protocols, associated responses, and mechanisms responsible for these changes during the application of IPC.

Dual-channel cascade pose estimation network trained on infrared thermal image and groundtruth annotation for real-time gait measurement.

Real-time spatiotemporal parameter measurement for gait analysis is challenging. Previous techniques for 3D motion analysis, such as inertial measurement units, marker based motion analysis or the use of depth cameras, require expensive equipment, highly skilled staff and limits feasibility for sustainable applications. In this paper a dual-channel cascaded network to perform contactless real-time 3D human pose estimation using a single infrared thermal video as an input is proposed. An algorithm to calculate gait spatiotemporal parameters is presented by tracking estimated joint locations. Additionally, a training dataset composed of infrared thermal images and groundtruth annotations has been developed. The annotation represents a set of 3D joint locations from infrared optical trackers, which is considered to be the gold standard in clinical applications. On the proposed dataset, our pose estimation framework achieved a 3D human pose mean error of below 21 mm and outperforms state-of-the-art methods. The results reveal that the proposed system achieves competitive skeleton tracking performance on par with the other motion capture devices and exhibited good agreement with a marker-based three-dimensional motion analysis system (3DMA) over a range of spatiotemporal parameters. Moreover, the process is shown to distinguish differences in over-ground gait parameters of older adults with and without Hemiplegia's disease. We believe that the proposed approaches can measure selected spatiotemporal gait parameters and could be effectively used in clinical or home settings.

The influence of whole body vibration on the central and peripheral cardiovascular system.

The purpose of this study was to investigate the physiological changes of the cardiovascular system in response to whole body vibration during quiet standing and identify whether there is a greater influence on the central or peripheral cardiovascular system. Twenty healthy participants (12 male and 8 female) were assessed over two separate testing sessions for changes in peripheral skin temperature, peripheral venous function, blood flow velocity in the dorsalis pedis artery, blood pressure and heart rate during quiet standing with 40 Hz 1·9 mm synchronous vibration. Vibration exposure totalled 5 min in 1 min increments with 5 min recovery during each testing session. There were no significant changes in heart rate, blood pressure or peripheral skin temperature. Significant results were obtained for blood flow velocity with increases from 0·5 + 0·2 cm·s(-1) at baseline to 1 + 0·2 cm·s(-1) during vibration, returning to baseline levels during the recovery period. Due to the absence of changes in heart rate, blood pressure or lower leg and foot temperature, the change in blood flow velocity can be attributed to changes in peripheral vascular function. The results suggest a high level of sensitivity of the peripheral vascular system to vibration exposure; therefore, further studies should be completed to ascertain the physiological mechanisms underlying the effects of vibration on the peripheral vascular system.

Post-activation potentiation: underlying physiology and implications for motor performance.

The response of muscle to volitional or electrically induced stimuli is affected by its contractile history. Fatigue is the most obvious effect of contractile history reflected by the inability of a muscle to generate an expected level of force. However, fatigue can coexist with post-activation potentiation (PAP), which serves to improve muscular performance, especially in endurance exercise and activities involving speed and power. The measured response of muscular performance following some form of contractile activity is the net balance between processes that cause fatigue and the simultaneous processes that result in potentiation. Optimal performance occurs when fatigue has subsided but the potentiated effect still exists. PAP has been demonstrated using electrically induced twitch contractions and attributed to phosphorylation of myosin regulatory light chains, which makes actin and myosin more sensitive to Ca(2+). The potentiated state has also been attributed to an increase in alpha-motoneuron excitability as reflected by changes in the H-reflex. However, the significance of PAP to functional performance has not been well established. A number of recent studies have applied the principles of PAP to short-term motor performance as well as using it as a rationale for producing long-term neuromuscular changes through complex training. Complex training is a training strategy that involves the execution of a heavy resistance exercise (HRE) prior to performing an explosive movement with similar biomechanical characteristics, referred to as a complex pair. The complex pair is then repeated for a number of sets and postulated that over time will produce long-term changes in the ability of a muscle to generate power. The results of these studies are equivocal at this time and, in fact, no training studies have actually been undertaken. The discrepancies among the results of the various studies is due in part to differences in methodology and design, with particular reference to the mode and intensity of the HRE, the length of the rest interval within and between the complex pairs, the type of explosive activity, the training history of the participants, and the nature of the dependent variables. In addition, few of the applied studies have actually included measures of twitch response or H-reflex to determine if the muscles of interest are potentiated. There is clearly more research required in order to clarify the functional significance of PAP and, in particular, the efficacy of complex training in producing long-term neuromuscular adaptations.

Sorghum genome sequencing by methylation filtration.

Sorghum bicolor is a close relative of maize and is a staple crop in Africa and much of the developing world because of its superior tolerance of arid growth conditions. We have generated sequence from the hypomethylated portion of the sorghum genome by applying methylation filtration (MF) technology. The evidence suggests that 96% of the genes have been sequence tagged, with an average coverage of 65% across their length. Remarkably, this level of gene discovery was accomplished after generating a raw coverage of less than 300 megabases of the 735-megabase genome. MF preferentially captures exons and introns, promoters, microRNAs, and simple sequence repeats, and minimizes interspersed repeats, thus providing a robust view of the functional parts of the genome. The sorghum MF sequence set is beneficial to research on sorghum and is also a powerful resource for comparative genomics among the grasses and across the entire plant kingdom. Thousands of hypothetical gene predictions in rice and Arabidopsis are supported by the sorghum dataset, and genomic similarities highlight evolutionarily conserved regions that will lead to a better understanding of rice and Arabidopsis.