Vibration discomfort of supine human body exposed to whole-body vibration: effect of vibration direction and magnitude.

Supine postures are increasingly adopted in medical transport, long-duration flights, and other healthcare environments. This study is aimed to identify the effect of vibration direction and magnitude on the objective and subjective responses of the human body in a supine posture. The transmissibilities to the head, chest, abdomen, and thighs of 12 male subjects were measured with single-axis random vibrations in longitudinal ( axis), lateral ( axis), and vertical ( axis) direction at 0.

Effects of mediolateral whole-body vibration during gait with additional cognitive load.

Whole-body vibration (WBV) may increase musculoskeletal disorder risk among workers standing on vibrating surfaces for prolonged periods. Limited studies were conducted to comprehend WBV impact on individuals engaged in dynamic activities. This study explored the effects of different horizontal WBV frequencies on gait parameters, lower limb kinematics, and the cognitive response of healthy subjects.

Advancements in Sensor Technologies and Control Strategies for Lower-Limb Rehabilitation Exoskeletons: A Comprehensive Review.

Lower-limb rehabilitation exoskeletons offer a transformative approach to enhancing recovery in patients with movement disorders affecting the lower extremities. This comprehensive systematic review delves into the literature on sensor technologies and the control strategies integrated into these exoskeletons, evaluating their capacity to address user needs and scrutinizing their structural designs regarding sensor distribution as well as control algorithms. The review examines various sensing modalities, including electromyography (EMG), force, displacement, and other innovative sensor types, employed in these devices to facilitate accurate and responsive motion control.

The relationship between jump and sprint performance in preschool children.

Background: Physical activity may help prevent the development of adverse health disorders in children. Thus, it is fundamental to assess key physical skills, such as jumping and running, from an early age. Several studies proposed test batteries to evaluate these motor skills in preschoolers, but no research studied their association.

Bioimpedance Vector Analysis-Derived Body Composition Influences Strength and Power in Alpine Skiers.

: Alpine ski racing is a complex sport where no single factor can exclusively account for performance. We assessed body composition, using bioelectrical impedance vector analysis (BIVA), and our purpose was to study its influence on the strength and power profile of young alpine skiers. : Anthropometric measurements and advanced BIVA parameters were recorded on eighteen alpine ski racers (6 females/12 males; 17.

Identification of Aluminothermic Reaction and Molten Aluminum Level through Vision System.

During the secondary production of aluminum, upon melting the scrap in a furnace, there is the possibility of developing an aluminothermic reaction, which produces oxides in the molten metal bath. Aluminum oxides must be identified and removed from the bath, as they modify the chemical composition and reduce the purity of the product. Furthermore, accurate measurement of molten aluminum level in a casting furnace is crucial to obtain an optimal liquid metal flow rate which influences the final product quality and process efficiency.

The Simultaneous Assessment of Time and Motion Response during Dual Tasks.

Measurement of reaction time in clinical settings is generally employed to assess cognitive abilities by having a subject perform standard simple tests. In this study, a new method of measuring response time (RT) was developed using a system composed of LEDs that emit light stimuli and are equipped with proximity sensors. The RT is measured as the time taken by the subject to turn off the LED target by moving the hand towards the sensor.

Corrigendum to "Energy analysis of gait in patients with down syndrome" [Heliyon 8 (11) (November 2022) Article e11702].

[This corrects the article DOI: 10.1016/j.heliyon.

Relation of digital arterial dysfunction to alternative frequency weightings of hand-transmitted vibration.

This study compared the relative performance of alternative frequency weightings of hand-transmitted vibration (HTV) to predict the extent of cold-induced vasoconstriction in the digital arteries of HTV workers. The cold response of digital arteries was related to measures of daily vibration exposure expressed in terms of r.m.

Algorithms for Vision-Based Quality Control of Circularly Symmetric Components.

Quality inspection in the industrial production field is experiencing a strong technological development that benefits from the combination of vision-based techniques with artificial intelligence algorithms. This paper initially addresses the problem of defect identification for circularly symmetric mechanical components, characterized by the presence of periodic elements. In the specific case of knurled washers, we compare the performances of a standard algorithm for the analysis of grey-scale image with a Deep Learning (DL) approach.

Influence of Foot Morphology on the Center of Pressure Pattern in Patients with Down Syndrome.

Background: The primary aim of this study was to assess how different conformations of the foot in individuals with Down syndrome affected the CoP during walking, and the secondary aim was to evaluate the effect of an excess of mass in young adults and children with Down syndrome and flat foot. The greater investigation of these aspects will allow for more targeted rehabilitation treatments to improve a patient's quality of life.

Methods: The tests were carried out on 217 subjects with Down syndrome, 65 children and 152 young adults, and on 30 healthy individuals, 19 children and 11 young adults.

Energy analysis of gait in patients with down syndrome.

Background: the primary aim of this study is to analyse the energy parameters of patients with Down syndrome compared to a control group and secondly to verify whether the sport activity leads to differences in energy expenditure.

Methods: 3 groups of subjects were identified: 8 healthy subjects and 147 subjects with Down syndrome, of whom 14 played sports at least once a week. An energy index was calculated, given by the ratio between potential and kinetic energy.

Effects of the whole-body vibration direction on the cognitive response of standing subjects.

This study aims to investigate the effect of whole-body vibration along different axes on the response time (RT) of standing subjects during a customised psychomotor vigilance task (PVT). Twenty-five subjects were exposed to harmonic vibration with amplitude of 0.7 m/s RMS and frequencies between 1.

The smart body concept as a demonstration of the overarching utility and benefits of 3D avatars in retail, health and wellbeing: an accuracy study of body measures from 3D reconstruction.

Recent developments in 3D graphic technologies enable the affordable and precise reconstruction of body scanned models that can be applied in a variety of verticals, such as fashion, fitness and wellness, and healthcare. The accuracy of body measurements is a crucial element for the successful application of avatars in the following use cases: Avatars that go beyond visual representation and offer intrinsic and precise anthropometric data defined as a smart body are discussed in this paper. In particular, this paper presents the Gate technology, an innovative, autonomous, sustainable body scanner, coupled with an automatic production pipeline and the concept of avatars as smart bodies.

Comparing Fatigue Reducing Stimulation Strategies During Cycling Induced by Functional Electrical Stimulation: a Case Study with one Spinal Cord Injured Subject.

This case study was designed starting from our experience at CYBATHLON 2020. The specific aim of this work was to compare the effectiveness of different fatigue reducing stimulation strategies during cycling induced by Functional Electrical Stimulation (FES). The compared stimulation strategies were: traditional constant frequency trains (CFTs) at 30 and 40Hz, doublet frequency trains (DFTs) and spatially distributed sequential stimulation (SDSS) on the quadriceps muscles.

Machine Learning-Based Estimation of Ground Reaction Forces and Knee Joint Kinetics from Inertial Sensors While Performing a Vertical Drop Jump.

Nowadays, the use of wearable inertial-based systems together with machine learning methods opens new pathways to assess athletes' performance. In this paper, we developed a neural network-based approach for the estimation of the Ground Reaction Forces (GRFs) and the three-dimensional knee joint moments during the first landing phase of the Vertical Drop Jump. Data were simultaneously recorded from three commercial inertial units and an optoelectronic system during the execution of 112 jumps performed by 11 healthy participants.

Fatigue Induced by Repeated Changes of Direction in Élite Female Football (Soccer) Players: Impact on Lower Limb Biomechanics and Implications for ACL Injury Prevention.

Background: The etiology of Anterior Cruciate Ligament (ACL) injury in women football results from the interaction of several extrinsic and intrinsic risk factors. Extrinsic factors change dynamically, also due to fatigue. However, existing biomechanical findings concerning the impact of fatigue on the risk of ACL injuries remains inconsistent.

Spatiotemporal gait parameter changes due to exposure to vertical whole-body vibration.

Background: Vertical whole-body vibration (vWBV) during work, recreation, and transportation can have detrimental effects on physical and mental health. Studies have shown that lateral vibration at low frequencies (<3 Hz) can result in changes to spatiotemporal gait parameters. There are few studies which explore spatiotemporal gait changes due to vertical vibration at higher frequencies (> 3 Hz).

Four degree-of-freedom lumped parameter model of the foot-ankle system exposed to vertical vibration from 10 to 60 Hz with varying centre of pressure conditions.

Modelling the foot-ankle system (FAS) while exposed to foot-transmitted vibration (FTV) is essential for designing inhibition methods to prevent the effects of vibration-induced white-foot. K-means analysis was conducted on a data set containing vibration transmissibility from the floor to 24 anatomical locations on the right foot of 21 participants. The K-means analysis found three locations to be sufficient for summarising the FTV response.

Machine-Learning Based Determination of Gait Events from Foot-Mounted Inertial Units.

A promising but still scarcely explored strategy for the estimation of gait parameters based on inertial sensors involves the adoption of machine learning techniques. However, existing approaches are reliable only for specific conditions, inertial measurements unit (IMU) placement on the body, protocols, or when combined with additional devices. In this paper, we tested an alternative gait-events estimation approach which is fully data-driven and does not rely on a priori models or assumptions.

Vibration transmissibility and apparent mass changes from vertical whole-body vibration exposure during stationary and propelled walking.

Whole-Body Vibration (WBV) is an occupational hazard affecting employees working with transportation, construction or heavy machinery. To minimize vibration-induced pathologies, ISO identified WBV exposure limits based on vibration transmissibility and apparent mass studies. The ISO guidelines do not account for variations in posture or movement.

3D Tracking of Human Motion Using Visual Skeletonization and Stereoscopic Vision.

The design of markerless systems to reconstruct human motion in a timely, unobtrusive and externally valid manner is still an open challenge. Artificial intelligence algorithms based on automatic landmarks identification on video images opened to a new approach, potentially e-viable with low-cost hardware. OpenPose is a library that t using a two-branch convolutional neural network allows for the recognition of skeletons in the scene.

Maturity offset affects standing postural control in youth male soccer players.

Quantifying the response of postural control in developmental athletes makes it possible to understand critical coordination and learning phases and to improve technical-physical interventions. However, the influence of maturation on postural control amongst young soccer players has neither been tested using quantitative methods, nor over a wide age range. In this study, we examined stabilometric parameters of 238 young male soccer players from 9 to 17 years old relative to maturity offset.

Use of Machine Learning and Wearable Sensors to Predict Energetics and Kinematics of Cutting Maneuvers.

Changes of directions and cutting maneuvers, including 180-degree turns, are common locomotor actions in team sports, implying high mechanical load. While the mechanics and neurophysiology of turns have been extensively studied in laboratory conditions, modern inertial measurement units allow us to monitor athletes directly on the field. In this study, we applied four supervised machine learning techniques (linear regression, support vector regression/machine, boosted decision trees and artificial neural networks) to predict turn direction, speed (before/after turn) and the related positive/negative mechanical work.

Standing centre of pressure alters the vibration transmissibility response of the foot.

Vibration-white foot as an occupational disease has underscored the need to better understand the vibration response of the foot. While vibration transmissibility data exist for a natural standing position, it is anticipated that weight distribution will affect the response. The purpose of this study was to determine the effects of changes in centre of pressure (COP) on the foot's biomechanical response.