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The present study had a dual objective: (1) to present and validate a predictive model of standing posture in the sagittal plane, joint torques and support forces for a smartphone user built from biomechanical principles; (2) propose risk scales for joint torques and reaction forces based on simulations in order to use them into the musculoskeletal disorders prevention. Comparison of the modelled data with experimental measurements (400 tested postures with sample size verification) for calling and texting tasks highlights the model's ability to correctly estimate posture and reaction forces on the ground. The model was able to provide estimates of the range of variation of each parameter for a wide range of environmental conditions as a function of the user body mass index (setting between 12.5 and 50). Joint torques risk scales have been constructed, especially for shoulder and elbow, to characterise the risks incurred by the users. Practitioner summary: The proposed model enables the postures, joint torques and reaction forces to be estimated from subject's body mass index and environmental configuration without resorting to experimentation, which is relevant in industry. This approach allows the proposition of new scales based on joint torques to reinforce the recommendations for MSDs prevention. Abbreviations: BMI: body mass index; LUBA: postural loading on the upper body assessment; MSDs: musculoskeletal disorders; RULA: rapid upper limb assessment; WHO: World Health Organization [ABSTRACT FROM AUTHOR]

Due to motor deficiencies inducing low force capabilities or tremor, many persons have great difficulties to use joystick-operated wheelchairs. To alleviate such difficulties, alternative interfaces using vocal, gaze, or brain signals are now becoming available. While promising, these systems still need to be evaluated thoroughly. In this framework, the aims of this study are to analyze and evaluate the behavior of 11 able-bodied subjects during a navigation task executed with gaze or joystick-operated electric wheelchair involving a door crossing. An electric wheelchair was equipped with retroreflective markers, and their movements were recorded with an optoelectronic system. The gaze commands were detected using an eye tracking device. Apart from classical, forward, backward, stop, left and right commands, the chosen screen-based interface integrated forward-right and forward-left commands. The global success rate with the gaze-based control was 80.3%. The path optimally ratio was 0.97 and the subject adopted similar trajectories with both systems. The results for gaze control are promising and highlight the important utilization of the forward-left and forward-right commands (25% of all issued commands) that may explain the similarity between the trajectories using both interfaces. [ABSTRACT FROM AUTHOR]

79% of smartphone users carry their phone 22 hours a day. In this context, the main task worldwide, texting, is performed under a wide range of light and position conditions. The aim of this study was to test the effects of environmental illumination and screen brightness settings on upper limb and axial skeleton parameters. Twelve subjects performed three trials of texting under three experimental positions, two screen luminance settings and three environmental light conditions. 3 D axial skeleton and upper limb angles, smartphone orientation and face-to-smartphone distance were used as dependent variables. High environmental illumination and/or low screen brightness resulted in an increase in interaction time and a reduction in the face-to-smartphone distance by approximately 10%. Subjects attempted to compensate for the unfavourable effects of such light conditions by adopting postures rated 5 in the Rapid Upper Limb Assessment, indicating an increased risk of developing musculoskeletal disorders. Practitioner's summary: The purpose of the study was to quantify the joint angles of the upper body in experimental conditions that represent daily life. Postures were influenced by ambient illumination and display brightness. The most harmful postures were observed when the display brightness was minimum, and the ambient light was similar to a sunny day. Abbreviations: ST: seated with table; SWT: seated without any support; STA: standing; 0L: in the dark, no light; AL: ambient light; SL: strong light; BrightMin: minimum display brightness; BrightMax: maximum display brightness (BrightMax); ISB: International Society of Biomechanics; RULA: rapid upper limb assessment; MSDs: musculoskeletal disorders [ABSTRACT FROM AUTHOR]

The aim of this study was to test the capacity of the force feasible set formalism to predict maximal force exertion during isometric handbraking. Maximal force exertion and upper-limb posture were measured with a force sensor embedded in a handbrake and an optoelectronic system, respectively. Eleven subjects participated in the experiment which consisted of exerting the maximal force in isometric conditions considering five hand brake positions relative to the seat H-point. Then, maximal force was predicted by the force feasible set obtained from an upper-limb musculoskeletal model. The root-mean-square (RMS) of the angle between measured and predicted forces was 8.4° while the RMS error (RMSE) for amplitude prediction was 95.4 N. However, predicted, and measured force amplitudes were highly correlated (r = 0.88, p < 0.05, slope = 0.97, intercept = 73.3N) attesting the capacity of the model to predict force exertion according to the subject's posture. The implications in the framework of ergonomics are then discussed. Practitioner summary: Maximal force exertion is of paramount importance in digital human modelling. We used the force feasible set formalism to predict maximal force exertion during handbraking from posture and anthropometric data. The predicted and measured force orientation showed a RMS of 8.4° while amplitude presented a RMSE of 95.4 N with a strong correlation (r = 0.88, p < 0.05, slope 0.97, intercept 77.3 N). [ABSTRACT FROM AUTHOR]

Aim: The study goals were to engineer and harvest scaffold-free undifferentiated/differentiated multilayer human adipose-derived stem cell (hADSC) cell sheets, in absence of treatment. Materials & methods: The hADSC are seeded in 35 mm culture dishes. At confluence or when multilayer cell sheets are formed, hADSC are treated with predefined differentiation culture media (adipocyte, chondrocyte and osteoblast). Results: Undifferentiated hADSC and differentiated adipocyte, osteoblast and chondrocyte hADSC multilayer cell sheets (hADSCmCS) have been harvested. Hematoxylin & eosin showed the formation of multilayer cell sheets. Undifferentiated hADSC multilayer cell sheets preserve their stem cell markers. Differentiated adipocyte, osteoblast and chondrocyte hADSCmCS expressed specific markers. Conclusion: This simple protocol opens possibilities to engineer scaffold-free hADSCm cell sheet to transplant them on damaged organs. The different possibilities to use adipose-derived stem cells multilayer cell sheets. [ABSTRACT FROM AUTHOR]

Developing tools to predict the force capabilities of the human limbs through the Force Feasible Set (FFS) may be of great interest for robotic assisted rehabilitation and digital human modelling for ergonomics. Indeed, it could help to refine rehabilitation programs for active participation during exercise therapy and to prevent musculoskeletal disorders. In this framework, the purpose of this study is to use artificial neural networks (ANN) to predict the FFS of the upper-limb based on joint centre Cartesian positions and anthropometric data. Seventeen right upper-limb musculoskeletal models based on individual anthropometric data are created. For each musculoskeletal model, the FFS is computed for 8428 different postures. For any combination of force direction and joint positions, ANNs can predict the FFS with high values of coefficient of determination (R2 > 0.89) between the true and predicted data. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to define the impact of regular practice of Nordic walking on the gait of the elderly. Thereby, we aimed to determine whether the gait characteristics of active elderly persons practicing Nordic walking are more similar to healthy adults than that of the sedentary elderly. Comparison was made based on parameters computed from three inertial sensors during walking at a freely chosen velocity. Results showed differences in gait pattern in terms of the amplitude computed from acceleration and angular velocity at the lumbar region (root mean square), the distribution (Skewness) quantified from the vertical and Euclidean norm of the lumbar acceleration, the complexity (Sample Entropy) of the mediolateral component of lumbar angular velocity and the Euclidean norm of the shank acceleration and angular velocity, the regularity of the lower limbs, the spatiotemporal parameters and the variability (standard deviation) of stance and stride durations. These findings reveal that the pattern of active elderly differs significantly from sedentary elderly of the same age while similarity was observed between the active elderly and healthy adults. These results advance that regular physical activity such as Nordic walking may counteract the deterioration of gait quality that occurs with aging. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the role of rotation axes during a tennis serve. A motion capture system was used to evaluate the contribution of the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis) during the four discrete tennis serve phases (loading, cocking, acceleration and follow through). Ten ranked athletes (International Tennis Number 1–3) repeatedly performed a flat service aiming at a target on the other side of the net. The four serve phases are distinct and thus, each movement phase seems to be organised around specific rotation axes. The results showed that the limbs’ rotational axis does not necessarily coincide with the minimum inertia axis across the cocking phase of the tennis serve. Even though individual serving strategies were exposed, all participants showed an effect due to the cocking phase and changed the rotation axis during the task. Taken together, the results showed that despite inter-individual differences, nine out of 10 participants changed the rotation axis towards the minimum inertia and/or the mass axis in an endeavour to maximise external rotation of the shoulder to optimally prepare for the acceleration phase. [ABSTRACT FROM PUBLISHER]

Nowadays touch technology is growing and developers try to make it ever more intuitive and easier to use. This present work focused on the upper limb joint coordination during the achievement of puzzles on touch screen. A 5-inch and 10-inch devices were used to perform 9 and 16 pieces puzzles dragged with digits. The conclusions showed an increase in joint solicitation with the number of piece and the touch screen size. Moreover, three interactions strategies proved to be an evidence: the ‘wrist strategy’ preferentially implying wrist flexion/extension, the ‘elbow strategy’ preferentially implying the elbow flexion/extension and the ‘neutral strategy’ mobilising equally the two joints. From an ergonomic point of view, the data about how the upper limb segments are mobilised while interacting with the screen could be relevant to increase the adaptability of the devices to the user, including users with motor impairments. Practitioner Summary:Information about the biomechanical organisation of movement during interaction with touch devices appears relevant in order to develop applications adapted to the motor capacities of users. From the analysis of joint angles when performing several times a puzzle with healthy subjects, three motor strategies were highlighted. [ABSTRACT FROM PUBLISHER]

The goal of this study is to investigate the influence of mental fatigue on the event related potential P300 features (maximum pick, minimum amplitude, latency and period) during virtual wheelchair navigation. For this purpose, an experimental environment was set up based on customizable environmental parameters (luminosity, number of obstacles and obstacles velocities). A correlation study between P300 and fatigue ratings was conducted. Finally, the best correlated features supplied three classification algorithms which are MLP (Multi Layer Perceptron), Linear Discriminate Analysis and Support Vector Machine. The results showed that the maximum feature over visual and temporal regions as well as period feature over frontal, fronto-central and visual regions were correlated with mental fatigue levels. In the other hand, minimum amplitude and latency features didn’t show any correlation. Among classification techniques, MLP showed the best performance although the differences between classification techniques are minimal. Those findings can help us in order to design suitable mental fatigue based wheelchair control. [ABSTRACT FROM PUBLISHER]

Keywords: Redundancy; range-of-motion; uncertainty; variability EN Redundancy range-of-motion uncertainty variability S194 S196 3 01/29/21 20191002 NES 191002 1. Introduction Robots will soon routinely collaborate with humans through cobots that assist the human operator's movements. Methods Interval analysis (Moore et al. [7]) provides the reliable mathematical framework which allows to model bounded uncertainties and to analyse imprecise kinematic models. [Extracted from the article]

Keywords: Hand movement; beta elliptic model; kinematic characteristics; beta impulses; curvilinear velocity EN Hand movement beta elliptic model kinematic characteristics beta impulses curvilinear velocity S188 S190 3 01/29/21 20191002 NES 191002 1. The examination of the experimental results confirmed the validity, throughout this age range, of the main kinematics models leading the hand movement curvilinear velocity as its overlapped Beta impulses shape. Hand movement, beta elliptic model, kinematic characteristics, beta impulses, curvilinear velocity. [Extracted from the article]

We examined the role of rotation axes during an overarm throwing task. Participants performed such task and were asked to throw a ball at maximal velocity at a target. The purpose of this study was to examine whether the minimum inertia axis would be exploited during the throwing phases, a time when internal–external rotations of the shoulder are particularly important. A motion capture system was used to evaluate the performance and to compute the potential axes of rotation (minimum inertia axis, shoulder–centre of mass axis and the shoulder–elbow axis). More specifically, we investigated whether a velocity-dependent change in rotational axes can be observed in the different throwing phases and whether the control obeys the principle of minimum inertia resistance. Our results showed that the limbs’ rotational axis mainly coincides with the minimum inertia axis during the cocking phase and with the shoulder–elbow axis during the acceleration phase. Besides these rotation axes changes, the use of interaction torque is also sequence-dependent. The sequence-dependent rotation axes changes associated with the use of interaction torque during the acceleration phase could be a key factor in the production of hand velocity at ball release. [ABSTRACT FROM PUBLISHER]

The aim of this study was to apply models derived from the robotics field to evaluate the human upper-limb force generation capacity. Four models were compared: the force ellipsoid (FE) and force polytope (FP) based on unit joint torques and the scaled FE (SFE) and scaled FP (SFP) based on maximum isometric joint torques. The four models were assessed from four upper-limb postures with varying elbow flexion (40°, 60°, 80° and 100°) measured by an optoelectronic system and their corresponding isometric joint torques. Ten subjects were recruited. Three specific ellipsoids and polytopes parameters were compared: isotropy, principal force orientation and volume. Isotropy showed that the ellipsoids and polytopes were elongated. The angle between the two ellipsoids main axis and the two polytopes remained low but increased with the elbow flexion. The FE and FP volumes increased and those of SFE and SFP decreased with the elbow flexion. The interest and limits of such models are discussed in the framework of ergonomics and rehabilitation. [ABSTRACT FROM PUBLISHER]

The use of a portable X-ray fluorescence spectrometer (PXRF) equipped with a miniaturised X-ray tube producing a small 8 mm diameter X-ray beam required the validation of two new sampling protocols for the immediate screening of occupational lead exposure. First, lead in dust and fumes, collected by Institute of Occupational Medicine (IOM) inhalable samplers on 25 mm diameter membrane filters, is quantified using PXRF. To account for irregular dust deposition, the filters are rotated manually by quarter turns. Multiple PXRF readings are collected from the central region and from two locations in the outer region. The inner region is distinguishable from the outer region, but the two outer region locations are indistinguishable. High correlations (R2 > 0.99) are found between the PXRF results and historical results obtained using a reference method based on a laboratory wavelength-dispersive sequential XRF instrument (WDXRF) for lead loadings between 1–161 μg. The PXRF results from the outer regions of the filters show a bias of −13% with respect to the WDXRF. Once this bias is allowed for, 95% of all PXRF results lie within −28% and +38% of the WDXRF results. Neither instrument accounts for potential dust accumulation on the walls of the IOM sampler. Therefore, methods based on their use can only be considered semi-quantitative. Second, a protocol combining direct PXRF measurements on workplace surfaces with surface wipes is designed for immediate on-site quantification of removable surface lead residues. The quantification of such residues by this method is compared with subsequent off-site wet chemistry analysis of the surface wipes. The two methods show a good correlation (R2 ∼ 0.88). The ratio of the amount of removable residues determined by PXRF and wipe sampling is close to one with range 0.26–3.94. It is demonstrated that PXRF can be used as an effective tool for the immediate screening of occupational lead exposure. Although this article focused on lead, PXRF can identify simultaneously a number of other metals. [ABSTRACT FROM AUTHOR]

The aim of this paper was to model the hand trajectory during grasping by an extension in 3D of the 2D written language beta-elliptic model. The interest of this model is that it takes into account both geometric and velocity information. The method relies on the decomposition of the task space trajectories in elementary bricks. The latter is characterized by a velocity profile modelled with beta functions and a geometry modelled with elliptic shapes. A data base of grasping movements has been constructed and the errors of reconstruction were assessed (distance and curvature) considering two variations of the beta-elliptic model (‘quarter ellipse’ and ‘two tangents points’ method). The results showed that the method based on two tangent points outperforms the quarter ellipse method with average and maximum relative errors of 2.73% and 8.62%, respectively, and a maximum curvature error of 9.26% for the former. This modelling approach can find interesting application to characterize the improvement due to a rehabilitation or teaching process by a quantitative measurement of hand trajectory parameters. [ABSTRACT FROM AUTHOR]

The purpose of this project was to develop and validate a hand wiping protocol to be used by occupational hygienists, scientists, or other competent persons, measuring skin exposure to lead in workplaces. Inadvertent lead ingestion is likely to occur once the hands of employees have become contaminated. Ideally, a hand wiping protocol should maximize the recovery of lead-based residues present on employees’ hands in a cost-effective and reproducible manner. This article describes an effective and practical hand wiping procedure. Here, two standardized protocols (A and B) are designed. Protocol A is a self-wiping protocol requiring employees to wipe their own hands using four separate and successive wipes. Protocol B involves a scientist wiping the hands of employees using four wipes, followed by employees self-wiping their hands using two wipes (total of six wipes). Both protocols are defined by four wipe passes over each hand using Ghost wipes. Because this study took place in the workplace rather than in a simulated laboratory environment, only the relative (i.e., not absolute) removal efficiencies of the hand wiping protocols have been assessed. The two protocols were first evaluated at a double glazing panel manufacturing site where between 248 μg and 4544 μg of lead was found on employees’ hands. A statistical analysis (t-test) on the mean relative lead levels recovered in the first parts of the protocols indicated that Protocol A was more efficient than Protocol B (73% for Protocol A vs. 65% for Protocol B). The relative recovery of the combined first two passes against the combined first three passes also confirmed the greater efficiency of Protocol A (83.3% for Protocol A vs. 76.5% for Protocol B). However, lead levels recovered on the fourth pass remain significant at more than 10% of the total recovered loadings. Nonetheless, Protocol A was preferred and further evaluated at a lead battery manufacturing site where between 149 μg and 18,784 μg of lead was found on employees’ hands. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to first investigate synchronous (SYN) versus asynchronous (ASY) mode of propulsion and, second, investigate the wheel camber effects on sprinting performance as well as temporal parameters. Method: Seven wheelchair basketball players performed four maximal eight-second sprints on a wheelchair ergometer. They repeated the test according to two modes of propulsion (SYN and ASY) and two wheel cambers (9° and 15°). Results: The mean maximal velocity and push power output was greater in the synchronous mode compared to the asynchronous mode for both camber angles. However, the fluctuation in the velocity profile is inferior for ASY versus SYN mode for both camber angles. Greater push time/cycle time (Pt/Ct) and arm frequency (AF) for synchronous mode versus asynchronous mode and inversely, lesser Ct and rest time (Rt) values for the synchronous mode, for which greater velocity were observed. Conclusions: SYN mode leads to better performance than ASY mode in terms of maximal propulsion velocity. However, ASY propulsion allows greater continuity of the hand-rim force application, reducing fluctuations in the velocity profile. The camber angle had no effect on ASY and SYN mean maximal velocity and push power output. [ABSTRACT FROM AUTHOR]

Objective.Endoscopic sphincterotomy plus large-balloon dilatation (ESLBD) has an efficacy equal to or higher than that of endoscopic sphincterotomy alone for biliary lithiasis extractions. Our purpose was to evaluate the feasibility, efficacy and morbidity of large-balloon dilatation of the sphincter of Oddi after sphincterotomy or infundibulotomy for large or multiple common bile duct stones. Material and methods. Retrospective analysis. Results.A total of 64 ESLBD procedures were performed in 62 patients: 57 after sphincterotomy and 7 after infundibulotomy. The feasibility was 100%, and full clearance of the common bile duct was achieved in a single session without using mechanical lithotripsy in 95.3% of cases. Short-term complications were observed in 9 patients (14%). There were no perforations. The most frequent complication was delayed bleeding (7.8%). There was no significant difference of overall complications after sphincterotomy or after infundibulotomy (12.3% vs. 28.6%, p = 0.25). The incidence of acute pancreatitis was significantly higher after infundibulotomy than after sphincterotomy (28.6% vs. 0%, p = 0.01). Conclusions. ESLBD after endoscopic sphincterotomy or infundibulotomy is a simple, reproducible and effective technique, associated with a low morbidity rate and helps in avoiding mechanical lithotripsy in 95.3% of cases for the endoscopic extraction of large or multiple common bile duct stones. [ABSTRACT FROM AUTHOR]

In this work, it is proposed to evaluate the upper-limb movements through a global index of performance borrowed from the field of robotics: the manipulability. For a given posture, this index quantifies the set of velocities that can be achieved at the wrist in all the Cartesian directions. The manipulability can be represented by an ellipsoid from which the volume and shape related parameters can be derived. During a reach to grasp movement, the ellipsoid obtained from experiment presented a flattened shape along the forearm longitudinal axis and an increased volume as the arm was extended. From this study, it is concluded that: (1) the ellipsoid volume reflects well the ability to generate speed at the wrist which is effectively maximal for an extended posture; (2) if maximal velocity is an important parameter it might be advisable to primarily move the hand perpendicularly to the forearm longitudinal axis. Practitioner Summary: The interest of manipulability indices is that they evaluate globally a posture of the upper-limb in relation to a given task. This original parameter could help to design environments or devices in order that the adopted postures maximise one particular aspect of the performance, i.e. the velocity of the hand. [ABSTRACT FROM PUBLISHER]

Measurement of upper-limb movements is important in various domains. In this article, an upper-limb three-dimensional movement recording technique is proposed based on only two electromagnetic sensors. Two joints are considered with a total of seven degrees of freedom (DoF; three translations and four rotations). The chosen sequence of joint rotations is compliant with ISB recommendations: the shoulder is modelled with a ball and socket joint with three DoF and the elbow with a one DoF revolute joint. This article is focused on the procedure used to calibrate and sense the upper-limb movements from the raw data coming from the flock of birds sensors. The principle of the method is to define the centre of the wrist, elbow and shoulder joints in the frame of the adequate sensor. This operation is done by performing calibration gestures. Results are proposed and commented. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess technical changes during constrained swimming in time-to-exhaustion tests. Ten swimmers of national standard performed a maximal 400-m front crawl and two sets of exhaustion tests at 95%, 100%, and 110% of mean 400-m speed. In the first set (free), swimmers had to maintain their speeds until exhaustion and mean stroke rate was recorded for each test. In the second set (controlled), the same speed and individual corresponding stroke rate were imposed. The durations of the exhaustion tests, relative durations of the stroke phases, and arm coordination were analysed. For each speed in the “controlled” set, the exhaustion tests were shorter. Moreover, variables were consistent, suggesting a stabilization of stroke technique. Under the free condition, stroke rate increased to compensate for the decrease in stroke length. At the same time, swimmers reduced the relative duration of their non-propulsive phases in favour of the propulsive phases. Thus, swimmers changed their arm coordination, which came close to an opposition mode. These two constraints enable swimmers both to maintain their stroking characteristics and develop compensatory mechanisms to maintain speed. Moreover, stroke rate can be seen as a useful tool for controlling arm technique during paced exercise. [ABSTRACT FROM AUTHOR]

Examines whether the European Community has the initiative to create its own peace policy in the Middle East. Information on the Arab-Israeli conflicts; Citing the visit of French President Jacques Chirac to the Middle East in October, 1996; United States (U.S.), and Israeli antagonism to Europe's involvement; Role of the Cold War, June 1967 war, 1973 October War, and the 1990 Gulf War in determining relations between the U.S., Western Europe, and the Middle East.

Keywords: Gait quality; elderly; inertial sensors EN Gait quality elderly inertial sensors S492 S493 2 01/29/21 20191002 NES 191002 1. The definition of these gait events is a crucial step for the assessment of the spatiotemporal gait parameters (velocity, stride length, stance, swing and double support duration duration). Concerning the variability aspect, two computed parameters (variability of stance duration and stride duration) discriminate the two groups. [Extracted from the article]

The article examines the comparison of a torque-based force polytopes with the exerted forces at hand. It mentions the determination in the Jacobian matrix J and its transpose from the arm posture knowledge by the joint angle vector q. It states that force space mapping of torques set is bounded by minimum and maximum values. It also emphasizes the reconsideration of the results in the studies of transverse plane wherein more information are required to generalise.

The article examines the proposal of a model of the intra-individual joint level variability of upper-limb posture based on uncontrolled manifold (UCM) hypothesis. It states that the joint angles elemental variables (EV) and the fingertip position task variable (TV) relationship is depicted by the chain forward kinematics. It also mentions the concern in monitoring the model by global parameters such as the synergy index and the effect of a pathology or age on the kinematics movement.

The article examines the efficiency of various methods of body segment inertial parameter (BSIP) estimation in the presentation of the force plate (FP) data as a gold standard to reconstruct force and moment components. It states the original dynamic identification model (OM) approach that compares with the measured ground reaction forces. It also mentions the advantage of validation approach in the BSIP estimation in the comparison between the other results and data bases.

The article presents a study which compares biomechanical index and robotic index in evaluating isometric force generation capabilities. The study uses three-segment kinematic chain model, Jacobian matrix, and singular value decomposition (SVD) to determine the difference between the two indices in assessing the force capabilities of the upper limb. Results show that biomechanical index has higher volume and more variability in matching the upper limb capabilities than robotic ellipsoids.

The article presents a study which quantifies the standing posture stability of a person due to the dominance of limbs during multi-joint movements. The study uses a multi-scale entropy (MSE) algorithm, 10-item version of Edinburgh Handedness Inventory and measures analysis of variance (MANOVA). Results reveal that the increase in velocity supplemented the three dimension (3D) displacements variability of shoulder-to-elbow axis and the postural sway has not been affected.

The article presents a study which investigates the comparison of two motion capture system in a standardised measurement conditions and to evaluate the accuracy of Optitrack system. The study used a 10 camera 250e Optitrack motion capture system to record rigid body movement across several conditions with a rate of 250Hz. The paired t-test shows significant differences between the relative measurements of the systems.

The article presents a study which aims to identify and create an indices from the dynamics and kinematics of the arm motion of a throwing task player concerning the time of release (ToR). Then study was conducted to seven subjects who were a novice dart players who were instructed to perform 25 dart throws in position under the rules of World Dart Federation. The study shows that the release of dart occurs just before the hand of the players reached its peak velocity.

The article discusses a study which aims to quantify the manipulability of the upper limb during manual wheelchair propulsion to examine changes in the combination of the degrees of freedom (DOF) in a given level of expertise. The study involved 10 paraplegic subjects and computed the manipulability indices by evaluating the capacity to generate end-effector Cartesian velocities. The study suggests that the manipulability index can be used in examining the effect of the wheelchair setting.

The article presents a study which proposes for evaluating indices in assessing the overall coordination of the upper-limb degrees of freedom (DOFs) during grasping task in an obstacle. An upper limb can be patterned by segments that are interconnected by joints of different structures and DOFs. The study uses manipulability that evaluates the capacity for generating end-effector Cartesian velocities, and it reveals that manipulability may be a relevant index in the analysis of human motion.

The article presents a case study of the wrist kinematics and hand shape of mouse lemur Microcebus murinus during grasping in locomotion and feeding. The mouse lemur from the breeding of Brunoy in Paris, France was filmed during an arboreal locomotion recorded at 200 frames per second (f/s) and during feeding at 25 f/s. It is concluded that the wrist kinematics of the mouse lemur manifested an independent grasping mechanism but a close posture of the hand during the two functions.

The article presents a new learning architecture applied to humanoid stability control based on pluridisciplinary bibliographical study. The study shows that the proposed intelligent control is designed to reproduce the central nervous system (CNS) hierarchical architecture and the different areas functioning mode. Moreover, multi-level multi-layered modules have able to deal the change of gait through weighted signals.

The article reports on results of a study of joint moment determination for ergonomic simulation of reaching movement. A description of the experimental set-up and measurement method is presented. The study concluded that the distance between desired trajectories and simulated trajectories increase for distal points.

The article presents the study that investigates the relations between L3/L4 interverterbal states, jerk, and center of pressure uring unipedal and bipedal standing situations.

The article explores the effect on placing different gyroscopes on the shank for gait events detection during different treadmill walking speed. Topics mentioned include the selection of the vertical component of ground reaction force for estimation of gait events, the lack of significant difference between the root mean square error of terminal foot contact and initial foot contact from different location of the device, and the accuracy of the gyroscopes for detection of gait events.

An abstract of the article "Biomechanical analysis of interaction strategies using touchscreen: preliminary study," by P. Gorce and colleagues is presented.

An abstract of the article "Validity of a low-cost wearable device for body sway parameter evaluation," by A. Rouis, N. Rezzoug, and P. Gorce is presented.

An abstract of the article "Validation of a low-cost wearable accelerometer for temporal gait parameter quantification" by K. Ben Mansour and colleagues is presented.

The article presents a study on the upper limb kinematics of a wheelchair user during throwing activities. It discusses how the study was conducted which involved a 30-year-old wheelchair user whose upper limb kinematics were compared while throwing a bowling ball on an ordinary wheelchair and a wheelchair that is specifically equipped. The results reportedly revealed that the ordinary wheelchair had an impact between its handrim and the hand while the special wheelchair had no impact.

The article examines the change of rotational axes of a multi-articulated limb from an articular axis of rotation in overarm throwing. It mentions the consistency of throwing styles of the subjects. It states the closeness of shoulder configurations with other athletic configurations such as baseball pitching or handball overarm throwing. It also emphasizes that due to high-velocity profiles, change of rotation axis was confirmed.

The article examines the acceloremetric signal in human motion by using a low-pass filter. It mentions that the use of such filter entails the need to maintain the signal assumed to occupy the lower extremity of the frequency spectrum with rejection noise. It notes the placement of several inertial sensors at different anatomical locations on the body. It also emphasizes the use of the residual analysis method that permits the best compromise between noise reduction and signal distortion.

The article discusses the proposed brain gaze system or brain and eyes wheelchair interface (BEWHEELI) project through brain-computer interfaces (BCI) for disabled or elderly persons with physical and mental abilities using electroencephalography (EEG) technology. It examines the comparison between the BEWHEELI and the efficiency of standard gazed-based system. It also emphasizes the system performance along with its navigation security.

The article presents a study which investigates the effect of unadapted body segment masses on the computation of articular efforts for paraplegic people's lateral transfer movement. The study measures the lateral transfer movement of a 60-year-old paraplegic individual, which involves kinematic chain, anthropometric model, and mechanical efforts on the hands. The study shows that segment masses influence computed articular effort in a little way only in reference to the whole body mass.

The article presents a study which proposes an index that prevents an upper-limb musculoskeletal disorder during wheelchair propulsion. It notes that the upper-limb is the most affected area of musculoskeletal disorders and the handrim wheelchair propulsion is an important vector of such injuries. The main risk factors of upper-limb injuries include movement amplitude, obesity and proximity of joint limits. Results of the study provide information on how to set a wheelchair to reduce disorders.

The article presents a study of the validity of the prosimian Microcebus murinus model in studying the grasping disorders in Parkinson's disease. In the study, the grasping biomechanics invariants were pointed out and the existence of these invariants in humans and the model is demonstrated. The findings supply a quantitative tool for assessing the ability to spawn the motor disorder of Parkinson's disease in animals and to test the effect of new therapeutic molecules on grasping disorders.

The article presents a study that focuses on the comparison in grasping abilities between adult and young chimpanzees and humans. It examines species and age differences in the use of different grasping strategies. The study reveals the greater variability of contacts and grasping of small objects by young subjects for both species. It also indicates the lower amount of force applied by chimpanzee thumb in a precision grip compared to human.