Influence Of Posture Research Articles

Sitting in Judgment: How Body Posture Influences Deception Detection and Gazing Behavior.

Body postures can affect how we process and attend to information. Here, a novel effect of adopting an open or closed posture on the ability to detect deception was investigated. It was hypothesized that the posture adopted by judges would affect their social acuity, resulting in differences in the detection of nonverbal behavior (i.e., microexpression recognition) and the discrimination of deceptive and truthful statements. In Study 1, adopting an open posture produced higher accuracy for detecting naturalistic lies, but no difference was observed in the recognition of brief facial expressions as compared to adopting a closed posture; trait empathy was found to have an additive effect on posture, with more empathic judges having higher deception detection scores. In Study 2, with the use of an eye-tracker, posture effects on gazing behavior when judging both low-stakes and high-stakes lies were measured. Sitting in an open posture reduced judges’ average dwell times looking at senders, and in particular, the amount and length of time they focused on their hands. The findings suggest that simply shifting posture can impact judges’ attention to visual information and veracity judgments (Mg = 0.40, 95% CI (0.03, 0.78)).

Young's Modulus of Bilateral Infraspinatus Tendon Measured in Different Postures by Shear Wave Elastography Before and After Exercise.

ObjectiveTo investigate the Young's modulus value of infraspinatus tendons using shear wave elastography (SWE) technique in normal adults, and to analyze the influence of gender, postures, exercise, and dominant side on Young's modulus of infraspinatus tendons.MethodsThis is a prospective cross‐sectional study. From January 2019 to July 2020, 14 healthy subjects were identified, including seven males and seven females aged between 24 to 34, with a mean age of 27.67 ± 3.08 years. The Young's modulus of their infraspinatus tendons was measured by two operators using SWE in neutral and maximum external rotation positions of both sides before exercise and the dominant side after exercise. The Young's modulus values in different sexes, different postures, before vs after exercise, and dominant vs non‐dominant side were statistically analyzed.ResultsAll 14 subjects completed the data collection process. The mean Young's modulus values of infraspinatus tendon for dominant sides in neutral position were 33.04 ± 3.01 kPa for males and 28.76 ± 3.09 kPa for females. And for non‐dominant sides in the neutral position, the values were 33.02 ± 2.38 kPa for males and 28.86 ± 2.47 kPa for females. In the maximum external rotation position, the values for dominant sides were 50.19 ± 4.86 kPa for males and 42.79 ± 4.44 kPa for females, and for non‐dominant sides were 50.95 ± 3.24 kPa for males and 42.42 ± 3.66 kPa for females. After exercise, the mean Young's modulus values of infraspinatus tendon for dominant sides in neutral position were 54.56 ± 3.76 kPa for males and 46.66 ± 5.99 kPa for females. And for the maximum external rotation position, the values were 59.13 ± 3.78 kPa for males and 54.49 ± 5.67 kPa for females. The Young's modulus of infraspinatus tendon in the neutral and maximum external rotation positions showed statistically significant differences in males and females, as well as before and after exercise (P < 0.05). However, the difference in Young's modulus between the dominant and non‐dominant sides was not statistically significant (P > 0.05). Intergroup reliability between both operators was excellent (ICC > 0.85).ConclusionThere are gender‐related differences and post‐exercise increase in Young's modulus, yet such a difference cannot be witnessed between the dominant and non‐dominant sides.

The influence of postural emotion cues on implicit trait judgements

Perceptions of others’ traits (e.g., trustworthiness or dominance) are influenced by the emotion displayed on their face. For instance, the same individual appears more trustworthy when they express happiness than when they express anger. This overextension of emotional expressions has been shown with facial expression but whether this phenomenon also occurs when viewing postural expressions was unknown. We sought to examine how expressive behaviour of the body would influence judgements of traits and how sensitivity to this cue develops. In the context of a storybook, adults (N = 35) and children (5 to 8 years old; N = 60) selected one of two partners to help face a challenge. The challenges required either a trustworthy or dominant partner. Participants chose between a partner with an emotional (happy/angry) face and neutral body or one with a neutral face and emotional body. As predicted, happy facial expressions were preferred over neutral ones when selecting a trustworthy partner and angry postural expressions were preferred over neutral ones when selecting a dominant partner. Children’s performance was not adult-like on most tasks. The results demonstrate that emotional postural expressions can also influence judgments of others’ traits, but that postural influence on trait judgments develops throughout childhood.

The influence of human interaction on the vibration of hand-held human-machine systems – The effect of body posture, feed force, and gripping forces on the vibration of hammer drills

In hand-held human machine systems the biodynamic response of the human hand arm system influences the overall dynamic behavior. The biodynamic response of the hand arm system is affected by several influencing factors. These influencing factors include the feed force, body posture, gripping force, and anthropometric properties. In present studies the importance of the gripping force on the biodynamic response is highlighted. In the state of the art; however, the magnitude of gripping forces as well as the influence of the human factors body posture and feed force on hammer drills for a larger group of professional users is unclear. To analyze the influence that these human factors have on hammer drill vibrations, a study with 15 professional power tool test personnel has been conducted. Characteristic gripping force values have been measured (Median: 84 N–156 N at the main handle, 10 N–30 N on the auxiliary handle) for different feed forces (100 N, 150 N, 200 N) and body postures. Then the influence of body posture, feed force, and gripping force on the hammer drill vibration is determined. A significant influence of the body posture (ANOVA: p = .003, r = .367) on the RMS acceleration of the main handle was observed. Furthermore, the feed force has a significant influence on the vibration of the hammer-drill for some groups. The data also demonstrates that for increasing gripping forces, the RMS of the acceleration and frequency weighted acceleration ahv on the main and auxiliary handle decrease. The findings of this study represent a starting point for the development of adjustable hand-arm models for the reproducible vibration assessment of power tools.

Exploring the influence of impact severity and posture on vertebral joint mechanics in an in-vitro porcine model

To date, no in vitro studies have been conducted to explore lumbar soft tissue injury potential and altered mechanical properties from exposure to impact forces. After a motor vehicle collision (MVC), the cause of reported acute onset low back pain is difficult to associate with potential soft tissue strain injury sites including the facet joint and innervated facet joint capsule ligament (FJC). Thus, the purpose of this investigation was to quantify intervertebral anterior-posterior (AP) translation and facet joint capsule strain under varying postures and impact severities. Seventy-two porcine spinal units were exposed to three levels of impact severity (4 g, 8 g, 11 g), and posture (Neutral, Flexion, Extension). Impacts were applied using a custom-built impact track that replicated parameters experienced in low to moderate speed rear-end MVCs. Flexion-extension and anterior-posterior shear neutral zone testing were completed prior to impact. AP intervertebral translation and the strain tensor of the facet capsule ligament were measured during impacts. A significant main effect of collision severity was observed for peak AP intervertebral translation (4 g—2.8 ±0.53 mm; 8 g—6.4 ±2.9 mm; 11 g—8.3 ±0.45 mm) and peak FJC shear strain (2.37% strain change from 4 g to 11 g impact severity). Despite observed main effects of impact severity, no influence of posture was observed. This lack of influence of posture and small FJC strain magnitudes suggest that the FJC does not appear to undergo injurious or permanent mechanical changes in response to low-to-moderate MVC impact scenarios.

ANALISIS POSTUR KERJA MENGGUNAKAN METODE RAPID UPPER LIMB ASSESSMENT (RULA) DI UMKM KERUPUK KEMPLANG 32 KECAMATAN BUMI WARAS BANDAR LAMPUNG

This study discusses work posture analysis using the rapid upper limb assessment (RULA) method at Kerupuk Kemplang 32 Micro Small and Medium Enterprises (MSMEs), Bumi Waras District, Bandar Lampung. The purpose of this study was to determine unsafe work postures for workers, and to minimize injuries to the skeletal system and nervous system caused by repetitive movements (Cumulative Trauma Disorders), how the influence of work attitudes or postures of workers and the workplace, provide recommendations for appropriate work postures. safe based on the upper limb assessment (RULA) method. This research is a descriptive study with data analysis using the RULA method. The data collection method uses primary data in the form of worker posture data which includes upper arms, forearms, wrists, hands, neck, back and legs. The results of this study indicate that the working posture of making kemplang cracker dough is divided into two activities, namely taking sago water and making the dough, both of which have a score of 7 which indicates Action Level 4 and the roasting section of kemplang crackers has the same score, 7 indicating Action Level 4. From these data, it can be concluded that this work posture needs to be improved in the near future.

Optimization of Robot Posture and Workpiece Setup in Robotic Milling With Stiffness Threshold

Industrial robot provides a promising alternative in freeform surface milling. However, due to its low stiffness, it is difficult to guarantee the machining quality. While existing research considers mainly the influence of robot posture on stiffness, the workpiece setup&#x0027;s influence is equally important. In this article, to ensure the overall workpiece&#x0027;s robot stiffness meets the requirement of stiffness threshold in robotic milling, a method for simultaneously optimizing the robot posture and the workpiece setup is proposed. First, to evaluate the robot stiffness during machining, this article presents a new stiffness index considering the robot&#x0027;s rotational deformation. And then, an optimization model is established to optimize both the robot redundancy and the workpiece setup, considering the constraints of joint limitation, singularity-free and collision-free. Moreover, for complex freeform surfaces, to obtain the minimum number of posture changes of the robot and workpiece under the premise of meeting the limit of stiffness threshold, this article constructs a minimum set covering problem, which is solved by a clustering algorithm and a greedy algorithm. Finally, simulations and experimental studies are conducted to validate the effectiveness of the proposed robot stiffness index and the proposed optimization method, showing that the robot stiffness is improved during a milling process of the entire workpiece.

Flexed lumbar spine postures are associated with greater strength and efficiency than lordotic postures during a maximal lift in pain-free individuals

BackgroundInspite of common lifting advice to maintain a lordotic posture, there is debate regarding optimal lumbar spine posture during lifting. To date, the influence of lumbar posture on trunk muscle recruitment, strength and efficiency during high intensity lifting has not been fully explored. Research questionHow do differences in lumbar posture influence trunk extensor strength (moment), trunk muscle activity, and neuromuscular efficiency during maximal lifting? MethodsTwenty-six healthy participants adopted three lumbar postures (maximal extension (lordotic), mid-range (flat-back), and fully flexed) in a free lifting position. Motion analysis and force measurements were used to determine the back extensor, hip and knee moments. Surface electromyography (EMG) of three trunk extensors and the internal obliques were recorded. Neuromuscular efficiency (NME) was expressed as a ratio of normalised extensor moment to normalised EMG. ResultsSignificantly higher back extensor moments were exerted when moving from an extended to mid-range, and from a mid-range to fully flexed lumbar posture. This was accompanied by a decrease in activity across all three back extensor muscles (P < 0.001) resulting in a higher NME of these muscles in more flexed postures. Change in lumbar posture did not influence hip or knee moments or internal oblique activation. SignificanceA flexed-back posture is associated with increased strength and efficiency of the back muscles compared to a lordotic posture. These findings further question the manual handling advice to lift with a lordotic lumbar spine.

Influence of head flexion and rotation on obstructive sleep apnea severity during supine sleep.

Head posture influences the collapsibility of the passive upper airway during anaesthesia. However, little is known about the impact of head posture during sleep. The objective of this study was to develop and validate an instrument to measure head posture during supine sleep and to apply this instrument to investigate the influence of head posture on obstructive sleep apnea (OSA) severity. A customized instrument to quantify head flexion and rotation during supine sleep was developed and validated in a benchtop experiment. Twenty-eight participants with suspected OSA were successfully studied using diagnostic polysomnography with the addition of the customized instrument. Head posture in supine sleep was discretized into four categories by two variables: head flexed or not (flexion >15°); and head rotated or not (rotation >45°). Sleep time in each posture and the posture-specific apnea-hypopnea index (AHI) were quantified. Linear mixed-effect modelling was applied to determine the influence of flexion and rotation on supine OSA severity. Twenty-four participants had ≥15min of supine sleep in at least one head-posture category. Only one participant had ≥15min of supine sleep time with the head extended. Head flexion was associated with a 12.9 events/h increase in the AHI (95% CI: 3.7-22.1, p=.007). Head rotation was associated with an 11.0 events/h decrease in the AHI (95% CI: 0.3-21.6, p=.04). Despite substantial interparticipant variability, head flexion worsened OSA severity, and head rotation improved OSA severity. Interventions to promote rotation and restrict flexion may have therapeutic benefit in selected patients.

Trajectory Planning of Spray Gun With Variable Posture for Irregular Plane Based on Boundary Constraint

In order to solve the problem of low spraying efficiency and excessive paint waste caused by overspray when the robot automatically sprays irregular plane, a method of spray trajectory planning with boundary-constrained considering spray gun changing posture is proposed. The static spraying model of the spray gun with variable posture, and the dynamic spraying model of the spray gun along the arc path are established separately, an optimization method for the symmetry of coating distribution based on the variable spray angle when the gun spraying along the arc path is proposed. Orthogonal experiment method based on numerical simulation is used to clarify the influence of boundary curve shape and spray gun posture on boundary constraint distance, the prediction of the value range of the boundary constraint distance at the boundary of different curvature radius is realized. Within the range of the value of the boundary constraint, combined with the equal division method of the plane intercept line and the distance search method, a boundary constraint spray path generation algorithm is established by setting a uniform boundary constraint distance value. Finally, a multivariable spraying parameter optimization algorithm based on PSO is established, the spraying velocity, spraying height and spraying angle in the dynamic spraying process are solved, and the coating uniformity is optimized. The effectiveness and feasibility of the proposed spray trajectory planning method is verified by robot spraying experiment for any irregular plane.

The comparison of the shoulder muscle activation in patients with rotator cuff tear under an abduction brace among the three postures

Background: Immobilization using an abduction brace is essential for the relaxation of the rotator cuff and scapular muscles and the prevention of a retear in patients with rotator cuff tear after arthroscopic rotator cuff repair (ARCR). However, thus far, the comparison of the scapular muscle activities has not been compared among different postures under an abduction brace in patients after ARCR. Objectives: The purpose of our study was to compare the scapular muscle activities among the supine position, sitting position, and walking under an abduction brace before and after ARCR Study Design: Observational, repeated measures study. Methods: Twelve patients with full-thickness rotator cuff tears were studied. The mean patient age was 64.7 years. The scapular muscle activations of the ipsilateral limbs were measured using surface electromyography in three postures: supine position, sitting position, and walking. The integrated electromyography relative values of the upper trapezius, anterior deltoid, middle deltoid, and biceps brachii were compared preoperatively and at two weeks after ARCR. Results: The trapezius, biceps brachii, and middle deltoid in the walking showed significantly higher integrated electromyography relative values than those in the supine position, preoperatively and at two weeks after surgery. The anterior deltoid in the sitting position had significantly higher integrated electromyography relative values than those in the supine position. Conclusions: Postures affected the scapular muscle activities in ARCR patients under an abduction brace. Understanding the influence of posture on the scapular muscle activity after ARCR will help rehabilitation accurately and appropriately.

Towards Pedestrian Target Detection with Optimized Mask R-CNN

Aiming at the problem of low pedestrian target detection accuracy, we propose a detection algorithm based on optimized Mask R-CNN which uses the latest research results of deep learning to improve the accuracy and speed of detection results. Due to the influence of illumination, posture, background, and other factors on the human target in the natural scene image, the complexity of target information is high. SKNet is used to replace the part of the convolution module in the depth residual network model in order to extract features better so that the model can adaptively select the best convolution kernel during training. In addition, according to the statistical law, the length-width ratio of the anchor box is modified to make it more accord with the natural characteristics of the pedestrian target. Finally, a pedestrian target dataset is established by selecting suitable pedestrian images in the COCO dataset and expanded by adding noise and median filtering. The optimized algorithm is compared with the original algorithm and several other mainstream target detection algorithms on the dataset; the experimental results show that the detection accuracy and detection speed of the optimized algorithm are improved, and its detection accuracy is better than other mainstream target detection algorithms.

Influence of Forward Head Posture on Cervicocephalic Kinesthesia and Electromyographic Activity of Neck Musculature in Asymptomatic Individuals

ObjectiveThe purpose of this study was to compare cervicocephalic kinesthesia and electromyographic (EMG) activity of neck muscles—upper trapezius (UT) and sternocleidomastoid (SCM)—between individuals with and without forward head posture (FHP) and to examine the correlation between cervicocephalic kinesthesia and craniovertebral angle (CVA). MethodsTwenty-two asymptomatic individuals with FHP and 22 without FHP were recruited for the present study. Craniovertebral angle was measured, and those with CVA ≤53° were assigned to the FHP group, whereas those with CVA >53° were assigned to the control group. Thereafter, cervicocephalic kinesthesia and EMG activity of the neck muscles were assessed. Cervicocephalic kinesthesia was measured using a head repositioning accuracy test for all cervical spine motions. EMG activity of the UT and SCM muscles was recorded at rest and during activity. ResultsPosition-sense error values were found to be significantly greater for all directions—ie, flexion, extension, side flexion, and rotation—in participants with FHP than those without (P < .05). EMG activity of the UT and SCM muscles was found to be significantly raised both at rest and during activity in individuals with FHP relative to the non-FHP group (P < .05). Position-sense error values showed a significant inverse correlation with CVA (P < .05). ConclusionFindings of the present study suggest that cervicocephalic kinesthesia and activation patterns of the neck muscles may be significantly altered in individuals with FHP. Also, cervicocephalic kinesthesia is significantly associated with the severity of FHP.

Influence of Tool Posture and Position on Stability in Milling with Parallel Kinematic Machine Tool

This paper investigated the machining stability influenced by tool posture and position in ball-end milling with parallel kinematic machine tool (PKM). Initially, the geometric structure was identified, and the machinery stiffness was measured by impulse respond method at several positions with four tool postures. Then, the milling tests were conducted on flat work surface using a ball-end mills. Cutting force and acceleration signals of milling tests were measured by three-axis dynamometer and accelerometer. Furthermore, these signals were analyzed by using Fast-Fourier transform and Hilbert–Huang transform (HHT). The results showed that the length of arm change with tool posture, where the machinery stiffness decreased with the total length of arms for any tool position. The experimental results also demonstrated the machining stability varied with tool posture; the trend of stability corresponds with the machinery stiffness. The vibration analysis by HHT presented the increasing of power level in the time–frequency plot when the length of arm increase during milling process. Therefore, the geometric influence must be considered to support process planning on the PKM.

Does Posture Influence the Stroop Effect?

Rosenbaum, Mama, and Algom (2017) reported that participants who completed the Stroop task (i.e., name the hue of a color word when the hue and word meaning are congruent or incongruent) showed a smaller Stroop effect (i.e., the difference in response times between congruent and incongruent trials) when they performed the task standing than when sitting. We report five attempted replications (analyzed sample sizes: N = 108, N = 108, N = 98, N = 78, and N = 51, respectively) of Rosenbaum et al.’s findings, which were conducted in two institutions. All experiments yielded the standard Stroop effect, but we failed to detect any consistent effect of posture (sitting vs. standing) on the magnitude of the Stroop effect. Taken together, the results suggest that posture does not influence the magnitude of the Stroop effect to the extent that was previously suggested.

Influence of different postures under vertical impact load on thoracolumbar burst fracture.

Clinical studies have extensively shown that burst fractures can cause severe and long-term neurological deficits. However, the mechanism of burst fracture is not clear, and the influence of different spinal postures on burst fracture is still unidentified. The study aimed at investigating the influence of different postures under vertical impact load on thoracolumbar burst fracture. A detailed nonlinear finite element model of T12-L2 segment was developed to investigate these problems. In this work, a rigid ball was used to vertically impact the finite element spinal segment, which emulated the process of burst fracture as in experimental condition. During the process, amounting to 9 different postures (normal, flexion, extension, right/left lateral bending of 8°, right/left axial rotation of 4° and 8°) were studied. Totally five failure modes were observed. Six different parameters, including vertebral height, vertebral bulge, interpedicular widening, vertebral kyphotic angle, posterior vertebral body angle, and joint facet contact force, were observed to evaluate the corresponding severity of burst fracture. Burst fracture in extension was the severest, and the loss of vertebral height in flexion was the most. The different postures in these simulations changed the morphology of intervertebral disc and facet joints force, resulting in different types of fracture.

KINEMATICS AND INJURY MECHANISM OF CYCLIST LOWER LIMB IN VEHICLE-TO-BICYCLE COLLISIONS

Accident data show that lower limb is one of the most frequently injured body parts for cyclists in vehicle collisions. However, studies of cyclist lower limb injuries and protection are still sparse. Therefore, the purpose of this study is to investigate the kinematics and injury mechanism of cyclist lower limb in vehicle-to-bicycle collisions considering different impact boundary conditions. To achieve this, the finite element (FE) modeling approach and an FE human body lower limb model with detailed muscles were employed, and impact boundary conditions with different vehicle front-end shapes and cycling postures were considered. Predictions of lower limb kinematics, knee ligament elongation and bending moment of upper and lower leg were used for analysis. The simulation results show that cycling posture has a significant influence on cyclist lower limb kinematics and injury risk, lateral bending toward the direction of vehicle or vehicle moving combining with lateral shearing is the main mechanism for cyclist knee ligament injuries, and injuries to long bones of cyclist leg in vehicle impacts could form lateral bending at both directions. The findings suggest that the influence of cycling posture and distinct difference in injury mechanism between cyclist and pedestrian should be considered in the assessment of vehicle safety design for cyclist lower limb protection.

Discharge of Air Gaps During Ground Potential Live-Line Work on Transmission Lines

Ground potential live-line work (GPLW) is a typical type of live-line work on transmission lines. In order to ensure the safety of live-line workers and reduce the consumption of test resources, the discharge of air gaps during GPLW on transmission lines was studied. Firstly, a breakdown voltage prediction method of GPLW air gaps was proposed, which can predict the breakdown voltage of GPLW air gaps. Subsequently, a discharge model of GPLW air gaps was proposed as well, so that the discharge characteristics of GPLW air gaps under different gap distances can be obtained more convenient. The prediction method and the discharge model were verified by switching impulse discharge tests of GPLW air gaps on UHV transmission lines, and the calculated results were close to the test results. Finally, the influence of live-line worker postures on discharge characteristics was studied. The results showed that workers should avoid causing protrusions of body parts in the course of work, which is more conducive to safety.

Reliability of short-term measurements of heart rate variability: Findings from a longitudinal study

Research on heart rate variability (HRV) received increasing attention. This study analysed the reliability of the most common HRV parameters for baseline measurements. 103 healthy students (83 women, M = 21.72 ± 3.31 years) participated in five short-term HRV sessions, each including supine, sitting, and standing positions, respectively, spanning a time interval of eleven months. Relative reliability was evaluated by intraclass correlation coefficients, and absolute reliability by standard errors of measurement, smallest real differences, and 95 % limits of random variation. No systematic mean differences between measurements emerged. Intraclass correlation coefficients were quite low (supine: .49–.64, sitting: .40–.57, standing: .35–.56). Absolute reliability indicators revealed pronounced variations between test and retest. Influences of posture and time between measurements on reliability were small and unsystematic. We conclude that such high levels of within-subjects variability in HRV measurements (a) hamper the detection of changes over time, and (b) should be considered carefully in future analyses.

The influence of posture and scapulothoracic orientation on the choice of humeral component retrotorsion in reverse total shoulder arthroplasty

The literature suggests implantation of the humeral component in reverse total shoulder arthroplasty (RTSA) in 0°-40° of retrotorsion without further specification. We hypothesized that optimal humeral component retrotorsion to avoid notching and gain balanced rotational capacity would dependon scapular position and posture. We investigated 200 shoulders in 100 patients with available whole-body computed tomography scans and created 3-dimensional models. Implantation of a humeral component in 20° of retrotorsion was simulated, and a correction angle (CA) to yield perfect opposition to the glenosphere was calculated. Patient-specific variables such as age, sex, posture, and scapular orientation parameters were correlated with this CA. Scapular orientation showed large interindividual differences. A highly significant correlation was seen between the CA and scapular internal rotation (R = 0.71, P < .001) and protraction (R = 0.39, P < .001). When the CA was adjusted for glenoid retroversion, the correlation coefficient of scapular internal rotation increased even further (R = 0.91, P < .001). Scapular internal rotation itself showed a correlation with thoracic kyphosis (R = 0.27, P < .001), protraction (R = 0.57, P < .001), tilt (R = 0.29, P < .001), and scapular translation (R = -0.23, P < .001). Scapular orientation and posture should be integrated into the determination process of humeral component retrotorsion in RTSA. In theory, implantation of the humeral component with increased retrotorsion leads to improved neutral opposition of the RTSA components in patients with extensive internal rotation of the scapula. On the basis of varying scapular internal rotation, we propose the distinction of 3 different posture types (A-C) for enhanced appraisal of scapulothoracic orientation.