A computer vision based candidate for functional balance test.

PubMed

Nalci, Alican; Khodamoradi, Alireza; Balkan, Ozgur; Nahab, Fatta; Garudadri, Harinath

2015-08-01

Balance in humans is a motor skill based on complex multimodal sensing, processing and control. Ability to maintain balance in activities of daily living (ADL) is compromised due to aging, diseases, injuries and environmental factors. Center for Disease Control and Prevention (CDC) estimate of the costs of falls among older adults was $34 billion in 2013 and is expected to reach $54.9 billion in 2020. In this paper, we present a brief review of balance impairments followed by subjective and objective tools currently used in clinical settings for human balance assessment. We propose a novel computer vision (CV) based approach as a candidate for functional balance test. The test will take less than a minute to administer and expected to be objective, repeatable and highly discriminative in quantifying ability to maintain posture and balance. We present an informal study with preliminary data from 10 healthy volunteers, and compare performance with a balance assessment system called BTrackS Balance Assessment Board. Our results show high degree of correlation with BTrackS. The proposed system promises to be a good candidate for objective functional balance tests and warrants further investigations to assess validity in clinical settings, including acute care, long term care and assisted living care facilities. Our long term goals include non-intrusive approaches to assess balance competence during ADL in independent living environments.

Acceleration feedback improves balancing against reflex delay

PubMed Central

Insperger, Tamás; Milton, John; Stépán, Gábor

2013-01-01

A model for human postural balance is considered in which the time-delayed feedback depends on position, velocity and acceleration (proportional–derivative–acceleration (PDA) feedback). It is shown that a PDA controller is equivalent to a predictive controller, in which the prediction is based on the most recent information of the state, but the control input is not involved into the prediction. A PDA controller is superior to the corresponding proportional–derivative controller in the sense that the PDA controller can stabilize systems with approximately 40 per cent larger feedback delays. The addition of a sensory dead zone to account for the finite thresholds for detection by sensory receptors results in highly intermittent, complex oscillations that are a typical feature of human postural sway. PMID:23173196

Balancing Human and Inter-Agent Influences for Shared Control of Bio-Inspired Collectives

DTIC Science & Technology

2014-10-01

the higher-level intelligence and ingenuity of a human operator as well as the collective intelligence and robustness of a bio-inspired collective...for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway...agents, or that receive information from, but are not directly controlled by, a human operator . Unlike, agents in the human-controlled partition, agents

Human-Inspired Eigenmovement Concept Provides Coupling-Free Sensorimotor Control in Humanoid Robot.

PubMed

Alexandrov, Alexei V; Lippi, Vittorio; Mergner, Thomas; Frolov, Alexander A; Hettich, Georg; Husek, Dusan

2017-01-01

Control of a multi-body system in both robots and humans may face the problem of destabilizing dynamic coupling effects arising between linked body segments. The state of the art solutions in robotics are full state feedback controllers. For human hip-ankle coordination, a more parsimonious and theoretically stable alternative to the robotics solution has been suggested in terms of the Eigenmovement (EM) control. Eigenmovements are kinematic synergies designed to describe the multi DoF system, and its control, with a set of independent, and hence coupling-free , scalar equations. This paper investigates whether the EM alternative shows "real-world robustness" against noisy and inaccurate sensors, mechanical non-linearities such as dead zones, and human-like feedback time delays when controlling hip-ankle movements of a balancing humanoid robot. The EM concept and the EM controller are introduced, the robot's dynamics are identified using a biomechanical approach, and robot tests are performed in a human posture control laboratory. The tests show that the EM controller provides stable control of the robot with proactive ("voluntary") movements and reactive balancing of stance during support surface tilts and translations. Although a preliminary robot-human comparison reveals similarities and differences, we conclude (i) the Eigenmovement concept is a valid candidate when different concepts of human sensorimotor control are considered, and (ii) that human-inspired robot experiments may help to decide in future the choice among the candidates and to improve the design of humanoid robots and robotic rehabilitation devices.

Human-Inspired Eigenmovement Concept Provides Coupling-Free Sensorimotor Control in Humanoid Robot

PubMed Central

Alexandrov, Alexei V.; Lippi, Vittorio; Mergner, Thomas; Frolov, Alexander A.; Hettich, Georg; Husek, Dusan

2017-01-01

Control of a multi-body system in both robots and humans may face the problem of destabilizing dynamic coupling effects arising between linked body segments. The state of the art solutions in robotics are full state feedback controllers. For human hip-ankle coordination, a more parsimonious and theoretically stable alternative to the robotics solution has been suggested in terms of the Eigenmovement (EM) control. Eigenmovements are kinematic synergies designed to describe the multi DoF system, and its control, with a set of independent, and hence coupling-free, scalar equations. This paper investigates whether the EM alternative shows “real-world robustness” against noisy and inaccurate sensors, mechanical non-linearities such as dead zones, and human-like feedback time delays when controlling hip-ankle movements of a balancing humanoid robot. The EM concept and the EM controller are introduced, the robot's dynamics are identified using a biomechanical approach, and robot tests are performed in a human posture control laboratory. The tests show that the EM controller provides stable control of the robot with proactive (“voluntary”) movements and reactive balancing of stance during support surface tilts and translations. Although a preliminary robot-human comparison reveals similarities and differences, we conclude (i) the Eigenmovement concept is a valid candidate when different concepts of human sensorimotor control are considered, and (ii) that human-inspired robot experiments may help to decide in future the choice among the candidates and to improve the design of humanoid robots and robotic rehabilitation devices. PMID:28487646

Vestibulospinal adaptation to microgravity

NASA Technical Reports Server (NTRS)

Paloski, W. H.

1998-01-01

Human balance control is known to be transiently disrupted after spaceflight; however, the mechanisms responsible for postflight postural ataxia are still under investigation. In this report, we propose a conceptual model of vestibulospinal adaptation based on theoretical adaptive control concepts and supported by the results from a comprehensive study of balance control recovery after spaceflight. The conceptual model predicts that immediately after spaceflight the balance control system of a returning astronaut does not expect to receive gravity-induced afferent inputs and that descending vestibulospinal control of balance is disrupted until the central nervous system is able to cope with the newly available vestibular otolith information. Predictions of the model are tested using data from a study of the neurosensory control of balance in astronauts immediately after landing. In that study, the mechanisms of sensorimotor balance control were assessed under normal, reduced, and/or altered (sway-referenced) visual and somatosensory input conditions. We conclude that the adaptive control model accurately describes the neurobehavioral responses to spaceflight and that similar models of altered sensory, motor, or environmental constraints are needed clinically to predict responses that patients with sensorimotor pathologies may have to various visual-vestibular or changing stimulus environments.

Changes in balance coordination and transfer to an unlearned balance task after slackline training: a self-organizing map analysis.

PubMed

Serrien, Ben; Hohenauer, Erich; Clijsen, Ron; Taube, Wolfgang; Baeyens, Jean-Pierre; Küng, Ursula

2017-11-01

How humans maintain balance and change postural control due to age, injury, immobility or training is one of the basic questions in motor control. One of the problems in understanding postural control is the large set of degrees of freedom in the human motor system. Therefore, a self-organizing map (SOM), a type of artificial neural network, was used in the present study to extract and visualize information about high-dimensional balance strategies before and after a 6-week slackline training intervention. Thirteen subjects performed a flamingo and slackline balance task before and after the training while full body kinematics were measured. Range of motion, velocity and frequency of the center of mass and joint angles from the pelvis, trunk and lower leg (45 variables) were calculated and subsequently analyzed with an SOM. Subjects increased their standing time significantly on the flamingo (average +2.93 s, Cohen's d = 1.04) and slackline (+9.55 s, d = 3.28) tasks, but the effect size was more than three times larger in the slackline. The SOM analysis, followed by a k-means clustering and marginal homogeneity test, showed that the balance coordination pattern was significantly different between pre- and post-test for the slackline task only (χ 2  = 82.247; p < 0.001). The shift in balance coordination on the slackline could be characterized by an increase in range of motion and a decrease in velocity and frequency in nearly all degrees of freedom simultaneously. The observation of low transfer of coordination strategies to the flamingo task adds further evidence for the task-specificity principle of balance training, meaning that slackline training alone will be insufficient to increase postural control in other challenging situations.

The frequency of human, manual adjustments in balancing an inverted pendulum is constrained by intrinsic physiological factors

PubMed Central

Loram, Ian D; Gawthrop, Peter J; Lakie, Martin

2006-01-01

While standing naturally and when manually or pedally balancing an equivalent inverted pendulum, the load sways slowly (characteristic unidirectional duration ∼1 s) and the controller, calf muscles or hand, makes more frequent adjustments (characteristic unidirectional duration 400 ms). Here we test the hypothesis that these durations reflect load properties rather than some intrinsic property of the human neuromuscular system. Using a specialized set-up mechanically analogous to real standing, subjects manually balanced inverted pendulums with different moments of inertia through a compliant spring representing the Achilles tendon. The spring bias was controlled by a sensitive joystick via a servo motor and accurate visual feedback was provided on an oscilloscope. As moment of inertia decreased, inverted pendulum sway size increased and it became difficult to sustain successful balance. The mean duration of unidirectional balance adjustments did not change. Moreover, the mean duration of unidirectional inverted pendulum sway reduced only slightly, remaining around 1 s. The simplest explanation is that balance was maintained by a process of manual adjustments intrinsically limited to a mean frequency of two to three unidirectional adjustments per second corresponding to intermittent control observed in manual tracking experiments. Consequently the inverted pendulum sway duration, mechanically related to the bias duration, reflects an intrinsic constraint of the neuromuscular control system. Given the similar durations of sway and muscle adjustments observed in real standing, we postulate that the characteristic duration of unidirectional standing sway reflects intrinsic intermittent control rather than the inertial properties of the body. PMID:16973712

Experimental neck muscle pain impairs standing balance in humans.

PubMed

Vuillerme, Nicolas; Pinsault, Nicolas

2009-02-01

Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pain on standing balance in young healthy adults. To achieve this goal, 16 male university students were asked to stand upright as still as possible on a force platform with their eyes closed in two conditions of No pain and Pain of the neck muscles elicited by experimental painful electrical stimulation. Postural control and postural performance were assessed by the displacements of the center of foot pressure (CoP) and of the center of mass (CoM), respectively. The results showed increased CoP and CoM displacements variance, range, mean velocity, and mean and median frequencies in the Pain relative to the No pain condition. The present findings emphasize the destabilizing effect of experimental neck muscle pain per se, and more largely stress the importance of intact neck neuromuscular function on standing balance.

An active balance board system with real-time control of stiffness and time-delay to assess mechanisms of postural stability.

PubMed

Cruise, Denise R; Chagdes, James R; Liddy, Joshua J; Rietdyk, Shirley; Haddad, Jeffrey M; Zelaznik, Howard N; Raman, Arvind

2017-07-26

Increased time-delay in the neuromuscular system caused by neurological disorders, concussions, or advancing age is an important factor contributing to balance loss (Chagdes et al., 2013, 2016a,b). We present the design and fabrication of an active balance board system that allows for a systematic study of stiffness and time-delay induced instabilities in standing posture. Although current commercial balance boards allow for variable stiffness, they do not allow for manipulation of time-delay. Having two controllable parameters can more accurately determine the cause of balance deficiencies, and allows us to induce instabilities even in healthy populations. An inverted pendulum model of human posture on such an active balance board predicts that reduced board rotational stiffness destabilizes upright posture through board tipping, and limit cycle oscillations about the upright position emerge as feedback time-delay is increased. We validate these two mechanisms of instability on the designed balance board, showing that rotational stiffness and board time-delay induced the predicted postural instabilities in healthy, young adults. Although current commercial balance boards utilize control of rotational stiffness, real-time control of both stiffness and time-delay on an active balance board is a novel and innovative manipulation to reveal balance deficiencies and potentially improve individualized balance training by targeting multiple dimensions contributing to standing balance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Balance Asymmetry in Parkinson’s Disease and Its Contribution to Freezing of Gait

PubMed Central

Boonstra, Tjitske A.; van Vugt, Jeroen P. P.; van der Kooij, Herman; Bloem, Bastiaan R.

2014-01-01

Balance control (the ability to maintain an upright posture) is asymmetrically controlled in a proportion of patients with Parkinson’s disease. Gait asymmetries have been linked to the pathophysiology of freezing of gait. We speculate that asymmetries in balance could contribute to freezing by a) hampering the unloading of the stepping leg and/or b) leading to a preferred stance leg during gait, which then results in asymmetric gait. To investigate this, we examined the relationship between balance control and weight-bearing asymmetries and freezing. We included 20 human patients with Parkinson (tested OFF medication; nine freezers) and nine healthy controls. Balance was perturbed in the sagittal plane, using continuous multi-sine perturbations, applied by a motion platform and by a force at the sacrum. Applying closed-loop system identification techniques, relating the body sway angle to the joint torques of each leg separately, determined the relative contribution of each ankle and hip joint to the total amount of joint torque. We also calculated weight-bearing asymmetries. We determined the 99-percent confidence interval of weight-bearing and balance-control asymmetry using the responses of the healthy controls. Freezers did not have larger asymmetries in weight bearing (p = 0.85) nor more asymmetrical balance control compared to non-freezers (p = 0.25). The healthy linear one-to-one relationship between weight bearing and balance control was significantly different for freezers and non-freezers (p = 0.01). Specifically, non-freezers had a significant relationship between weight bearing and balance control (p = 0.02), whereas this relation was not significant for freezers (p = 0.15). Balance control is asymmetrical in most patients (about 75 percent) with Parkinson’s disease, but this asymmetry is not related to freezing. The relationship between weight bearing and balance control seems to be less pronounced in freezers, compared to healthy controls and non-freezers. However, this relationship should be investigated further in larger groups of patients. PMID:25032994

Design of two wheel self balancing car

NASA Astrophysics Data System (ADS)

He, Chun-hong; Ren, Bin

2018-02-01

This paper proposes a design scheme of the two-wheel self-balancing dolly, the integration of the gyroscope and accelerometer MPU6050 constitutes the car position detection device.System selects 32-bit MCU stmicroelectronics company as the control core, completed the processing of sensor signals, the realization of the filtering algorithm, motion control and human-computer interaction. Produced and debugging in the whole system is completed, the car can realize the independent balance under the condition of no intervention. The introduction of a suitable amount of interference, the car can adjust quickly to recover and steady state. Through remote control car bluetooth module complete forward, backward, turn left and other basic action..

PID Controller Design for FES Applied to Ankle Muscles in Neuroprosthesis for Standing Balance

PubMed Central

Rouhani, Hossein; Same, Michael; Masani, Kei; Li, Ya Qi; Popovic, Milos R.

2017-01-01

Closed-loop controlled functional electrical stimulation (FES) applied to the lower limb muscles can be used as a neuroprosthesis for standing balance in neurologically impaired individuals. The objective of this study was to propose a methodology for designing a proportional-integral-derivative (PID) controller for FES applied to the ankle muscles toward maintaining standing balance for several minutes and in the presence of perturbations. First, a model of the physiological control strategy for standing balance was developed. Second, the parameters of a PID controller that mimicked the physiological balance control strategy were determined to stabilize the human body when modeled as an inverted pendulum. Third, this PID controller was implemented using a custom-made Inverted Pendulum Standing Apparatus that eliminated the effect of visual and vestibular sensory information on voluntary balance control. Using this setup, the individual-specific FES controllers were tested in able-bodied individuals and compared with disrupted voluntary control conditions in four experimental paradigms: (i) quiet-standing; (ii) sudden change of targeted pendulum angle (step response); (iii) balance perturbations that simulate arm movements; and (iv) sudden change of targeted angle of a pendulum with individual-specific body-weight (step response). In paradigms (i) to (iii), a standard 39.5-kg pendulum was used, and 12 subjects were involved. In paradigm (iv) 9 subjects were involved. Across the different experimental paradigms and subjects, the FES-controlled and disrupted voluntarily-controlled pendulum angle showed root mean square errors of <1.2 and 2.3 deg, respectively. The root mean square error (all paradigms), rise time, settle time, and overshoot [paradigms (ii) and (iv)] in FES-controlled balance were significantly smaller or tended to be smaller than those observed with voluntarily-controlled balance, implying improved steady-state and transient responses of FES-controlled balance. At the same time, the FES-controlled balance required similar torque levels (no significant difference) as voluntarily-controlled balance. The implemented PID parameters were to some extent consistent among subjects for standard weight conditions and did not require prolonged individual-specific tuning. The proposed methodology can be used to design FES controllers for closed-loop controlled neuroprostheses for standing balance. Further investigation of the clinical implementation of this approach for neurologically impaired individuals is needed. PMID:28676739

Toward Balance Recovery With Leg Prostheses Using Neuromuscular Model Control

PubMed Central

Geyer, Hartmut

2016-01-01

Objective Lower limb amputees are at high risk of falling as current prosthetic legs provide only limited functionality for recovering balance after unexpected disturbances. For instance, the most established control method used on powered leg prostheses tracks local joint impedance functions without taking the global function of the leg in balance recovery into account. Here we explore an alternative control policy for powered transfemoral prostheses that considers the global leg function and is based on a neuromuscular model of human locomotion. Methods We adapt this model to describe and simulate an amputee walking with a powered prosthesis using the proposed control, and evaluate the gait robustness when confronted with rough ground and swing leg disturbances. We then implement and partially evaluate the resulting controller on a leg prosthesis prototype worn by a non-amputee user. Results In simulation, the proposed prosthesis control leads to gaits that are more robust than those obtained by the impedance control method. The initial hardware experiments with the prosthesis prototype show that the proposed control reproduces normal walking patterns qualitatively and effectively responds to disturbances in early and late swing. However, the response to mid-swing disturbances neither replicates human responses nor averts falls. Conclusions The neuromuscular model control is a promising alternative to existing prosthesis controls, although further research will need to improve on the initial implementation and determine how well these results transfer to amputee gait. Significance This work provides a potential avenue for future development of control policies that help improve amputee balance recovery. PMID:26315935

Reliability of assessing postural control during seated balancing using a physical human-robot interaction.

PubMed

Ramadan, Ahmed; Cholewicki, Jacek; Radcliffe, Clark J; Popovich, John M; Reeves, N Peter; Choi, Jongeun

2017-11-07

This study evaluated the within- and between-visit reliability of a seated balance test for quantifying trunk motor control using input-output data. Thirty healthy subjects performed a seated balance test under three conditions: eyes open (EO), eyes closed (EC), and eyes closed with vibration to the lumbar muscles (VIB). Each subject performed three trials of each condition on three different visits. The seated balance test utilized a torque-controlled robotic seat, which together with a sitting subject resulted in a physical human-robot interaction (pHRI) (two degrees-of-freedom with upper and lower body rotations). Subjects balanced the pHRI by controlling trunk rotation in response to pseudorandom torque perturbations applied to the seat in the coronal plane. Performance error was expressed as the root mean square (RMSE) of deviations from the upright position in the time domain and as the mean bandpass signal energy (E mb ) in the frequency domain. Intra-class correlation coefficients (ICC) quantified the between-visit reliability of both RMSE and E mb . The empirical transfer function estimates (ETFE) from the perturbation input to each of the two rotational outputs were calculated. Coefficients of multiple correlation (CMC) quantified the within- and between-visit reliability of the averaged ETFE. ICCs of RMSE and E mb for all conditions were ≥0.84. The mean within- and between-visit CMCs were all ≥0.96 for the lower body rotation and ≥0.89 for the upper body rotation. Therefore, our seated balance test consisting of pHRI to assess coronal plane trunk motor control is reliable. Copyright © 2017 Elsevier Ltd. All rights reserved.

On the Skill of Balancing While Riding a Bicycle

PubMed Central

Cain, Stephen M.; Ashton-Miller, James A.; Perkins, Noel C.

2016-01-01

Humans have ridden bicycles for over 200 years, yet there are no continuous measures of how skill differs between novice and expert. To address this knowledge gap, we measured the dynamics of human bicycle riding in 14 subjects, half of whom were skilled and half were novice. Each subject rode an instrumented bicycle on training rollers at speeds ranging from 1 to 7 m/s. Steer angle and rate, steer torque, bicycle speed, and bicycle roll angle and rate were measured and steering power calculated. A force platform beneath the roller assembly measured the net force and moment that the bicycle, rider and rollers exerted on the floor, enabling calculations of the lateral positions of the system centers of mass and pressure. Balance performance was quantified by cross-correlating the lateral positions of the centers of mass and pressure. The results show that all riders exhibited similar balance performance at the slowest speed. However at higher speeds, the skilled riders achieved superior balance performance by employing more rider lean control (quantified by cross-correlating rider lean angle and bicycle roll angle) and less steer control (quantified by cross-correlating steer rate and bicycle roll rate) than did novice riders. Skilled riders also used smaller steering control input with less variation (measured by average positive steering power and standard deviations of steer angle and rate) and less rider lean angle variation (measured by the standard deviation of the rider lean angle) independent of speed. We conclude that the reduction in balance control input by skilled riders is not due to reduced balance demands but rather to more effective use of lean control to guide the center of mass via center of pressure movements. PMID:26910774

Physical load handling and listening comprehension effects on balance control.

PubMed

Qu, Xingda

2010-12-01

The purpose of this study was to determine the physical load handling and listening comprehension effects on balance control. A total of 16 young and 16 elderly participants were recruited in this study. The physical load handling task required holding a 5-kg load in each hand with arms at sides. The listening comprehension task involved attentive listening to a short conversation. Three short questions were asked regarding the conversation right after the testing trial to test the participants' attentiveness during the experiment. Balance control was assessed by centre of pressure-based measures, which were calculated from the force platform data when the participants were quietly standing upright on a force platform. Results from this study showed that both physical load handling and listening comprehension adversely affected balance control. Physical load handling had a more deleterious effect on balance control under the listening comprehension condition vs. no-listening comprehension condition. Based on the findings from this study, interventions for the improvement of balance could be focused on avoiding exposures to physically demanding tasks and cognitively demanding tasks simultaneously. STATEMENT OF RELEVANCE: Findings from this study can aid in better understanding how humans maintain balance, especially when physical and cognitive loads are applied. Such information is useful for developing interventions to prevent fall incidents and injuries in occupational settings and daily activities.

Human stick balancing: Tuning Lèvy flights to improve balance control

NASA Astrophysics Data System (ADS)

Cabrera, Juan Luis; Milton, John G.

2004-09-01

State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lévy flight. The Lévy index, α, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index α does not change. However, the tails of the Lévy distribution become broader. These observations suggest a Lévy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lévy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lévy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings.

Balancing with Vibration: A Prelude for “Drift and Act” Balance Control

PubMed Central

Milton, John G.; Ohira, Toru; Cabrera, Juan Luis; Fraiser, Ryan M.; Gyorffy, Janelle B.; Ruiz, Ferrin K.; Strauss, Meredith A.; Balch, Elizabeth C.; Marin, Pedro J.; Alexander, Jeffrey L.

2009-01-01

Stick balancing at the fingertip is a powerful paradigm for the study of the control of human balance. Here we show that the mean stick balancing time is increased by about two-fold when a subject stands on a vibrating platform that produces vertical vibrations at the fingertip (0.001 m, 15–50 Hz). High speed motion capture measurements in three dimensions demonstrate that vibration does not shorten the neural latency for stick balancing or change the distribution of the changes in speed made by the fingertip during stick balancing, but does decrease the amplitude of the fluctuations in the relative positions of the fingertip and the tip of the stick in the horizontal plane, A(x,y). The findings are interpreted in terms of a time-delayed “drift and act” control mechanism in which controlling movements are made only when controlled variables exceed a threshold, i.e. the stick survival time measures the time to cross a threshold. The amplitude of the oscillations produced by this mechanism can be decreased by parametric excitation. It is shown that a plot of the logarithm of the vibration-induced increase in stick balancing skill, a measure of the mean first passage time, versus the standard deviation of the A(x,y) fluctuations, a measure of the distance to the threshold, is linear as expected for the times to cross a threshold in a stochastic dynamical system. These observations suggest that the balanced state represents a complex time–dependent state which is situated in a basin of attraction that is of the same order of size. The fact that vibration amplitude can benefit balance control raises the possibility of minimizing risk of falling through appropriate changes in the design of footwear and roughness of the walking surfaces. PMID:19841741

Control of whole body balance in the frontal plane during human walking.

PubMed

MacKinnon, C D; Winter, D A

1993-06-01

A whole-body inverted pendulum model was used to investigate the control of balance and posture in the frontal plane during human walking. The model assessed the effects of net joint moments, joint accelerations and gravitational forces acting about the supporting foot and hip. Three video cameras and two force platforms were used to collect kinematic and kinetic data from repeat trials on four subjects during natural walking. An inverse solution was used to calculate net joint moments and powers. Whole body balance was ensured by the centre of mass (CM) passing medial to the supporting foot, thus creating a continual state of dynamic imbalance towards the centerline of the plane of progression. The medial acceleration of the CM was primarily generated by a gravitational moment about the supporting foot, whose magnitude was established at initial contact by the lateral placement of the new supporting foot relative to the horizontal location of the CM. Balance of the trunk and swing leg about the supporting hip was maintained by an active hip abduction moment, which recognized the contribution of the passive accelerational moment, and countered a large destabilizing gravitational moment. Posture of the upper trunk was regulated by the spinal lateral flexors. Interactions between the supporting foot and hip musculature to permit variability in strategies used to maintain balance were identified. Possible control strategies and muscle activation synergies are discussed.

Development of a Self-Balancing Human Transportation Vehicle for the Teaching of Feedback Control

ERIC Educational Resources Information Center

Lin, Shui-Chun; Tsai, Ching-Chih

2009-01-01

Control systems education often needs to design interesting hands-on exercises that keep students interested in the control theory presented in lectures. These exercises include system modeling, system analyses, controller syntheses, implementation, experimentation, and performance evaluation of a control system. This paper presents an interesting…

Independent effects of adding weight and inertia on balance during quiet standing

PubMed Central

2012-01-01

Background Human balance during quiet standing is influenced by adding mass to the body with a backpack, with symmetrically-applied loads to the trunk, or with obesity. Adding mass to the body increases both the weight and inertia of the body, which theoretically could provide counteracting effects on body dynamics and balance. Understanding the independent effects of adding weight and inertia on balance may provide additional insight into human balance that could lead to novel advancements in balance training and rehabilitation. Therefore, the purpose of this study was to investigate the independent effects of adding weight and inertia on balance during quiet standing. Methods Sixteen normal-weight young adult participants stood as still as possible on a custom-built backboard apparatus under four experimental conditions: baseline, added inertia only, added weight only, and added inertia and weight. Results Adding inertia by itself had no measurable effect on center of pressure movement or backboard movement. Adding weight by itself increased center of pressure movement (indicated greater effort by the postural control system to stand as still as possible) and backboard movement (indicating a poorer ability of the body to stand as still as possible). Adding inertia and weight at the same time increased center of pressure movement but did not increase backboard movement compared to the baseline condition. Conclusions Adding inertia and adding weight had different effects on balance. Adding inertia by itself had no effect on balance. Adding weight by itself had a negative effect on balance. When adding inertia and weight at the same time, the added inertia appeared to lessen (but did not eliminate) the negative effect of adding weight on balance. These results improve our fundamental understanding of how added mass influences human balance. PMID:22507125

Independent effects of adding weight and inertia on balance during quiet standing.

PubMed

Costello, Kerry Elizabeth; Matrangola, Sara Louise; Madigan, Michael Lawrence

2012-04-16

Human balance during quiet standing is influenced by adding mass to the body with a backpack, with symmetrically-applied loads to the trunk, or with obesity. Adding mass to the body increases both the weight and inertia of the body, which theoretically could provide counteracting effects on body dynamics and balance. Understanding the independent effects of adding weight and inertia on balance may provide additional insight into human balance that could lead to novel advancements in balance training and rehabilitation. Therefore, the purpose of this study was to investigate the independent effects of adding weight and inertia on balance during quiet standing. Sixteen normal-weight young adult participants stood as still as possible on a custom-built backboard apparatus under four experimental conditions: baseline, added inertia only, added weight only, and added inertia and weight. Adding inertia by itself had no measurable effect on center of pressure movement or backboard movement. Adding weight by itself increased center of pressure movement (indicated greater effort by the postural control system to stand as still as possible) and backboard movement (indicating a poorer ability of the body to stand as still as possible). Adding inertia and weight at the same time increased center of pressure movement but did not increase backboard movement compared to the baseline condition. Adding inertia and adding weight had different effects on balance. Adding inertia by itself had no effect on balance. Adding weight by itself had a negative effect on balance. When adding inertia and weight at the same time, the added inertia appeared to lessen (but did not eliminate) the negative effect of adding weight on balance. These results improve our fundamental understanding of how added mass influences human balance.

Human balancing of an inverted pendulum: position control by small, ballistic-like, throw and catch movements

PubMed Central

Loram, Ian D; Lakie, Martin

2002-01-01

In standing, there are small sways of the body. Our interest is to use an artificial task to illuminate the mechanisms underlying the sways and to account for changes in their size. Using the ankle musculature, subjects balanced a large inverted pendulum. The equilibrium of the pendulum is unstable and quasi-regular sway was observed like that in quiet standing. By giving full attention to minimising sway subjects could systematically reduce pendulum movement. The pendulum position, the torque generated at each ankle and the soleus and tibialis anterior EMGs were recorded. Explanations about how the human inverted pendulum is balanced usually ignore the fact that balance is maintained over a range of angles and not just at one angle. Any resting equilibrium position of the pendulum is unstable and in practice temporary; movement to a different resting equilibrium position can only be accomplished by a biphasic ‘throw and catch’ pattern of torque and not by an elastic mechanism. Results showed that balance was achieved by the constant repetition of a neurally generated ballistic-like biphasic pattern of torque which can control both position and sway size. A decomposition technique revealed that there was a substantial contribution to changes in torque from intrinsic mechanical ankle stiffness; however, by itself this was insufficient to maintain balance or to control position. Minimisation of sway size was caused by improvement in the accuracy of the anticipatory torque impulses. We hypothesise that examination of centre of mass and centre of pressure data for quiet standing will duplicate these results. PMID:11986396

Destabilization of Human Balance Control by Static and Dynamic Head Tilts

NASA Technical Reports Server (NTRS)

Paloski, William H.; Wood, Scott J.; Feiveson, Alan H.; Black, F. Owen; Hwang, Emma Y.; Reschke, Millard F.

2004-01-01

To better understand the effects of varying head movement frequencies on human balance control, 12 healthy adult humans were studied during static and dynamic (0.14,0.33,0.6 Hz) head tilts of +/-30deg in the pitch and roll planes. Postural sway was measured during upright stance with eyes closed and altered somatosensory inputs provided by a computerized dynamic posturography (CDP) system. Subjects were able to maintain upright stance with static head tilts, although postural sway was increased during neck extension. Postural stability was decreased during dynamic head tilts, and the degree of destabilization varied directly with increasing frequency of head tilt. In the absence of vision and accurate foot support surface inputs, postural stability may be compromised during dynamic head tilts due to a decreased ability of the vestibular system to discern the orientation of gravity.

Human stick balancing: tuning Lèvy flights to improve balance control.

PubMed

Cabrera, Juan Luis; Milton, John G

2004-09-01

State-dependent, or parametric, noise is an essential component of the neural control mechanism for stick balancing at the fingertip. High-speed motion analysis in three dimensions demonstrates that the controlling movements made by the fingertip during stick balancing can be described by a Lèvy flight. The Lèvy index, alpha, is approximately 0.9; a value close to optimal for a random search. With increased skill, the index alpha does not change. However, the tails of the Lèvy distribution become broader. These observations suggest a Lèvy flight that is truncated by the properties of the nervous and musculoskeletal system; the truncation decreasing as skill level increases. Measurements of the cross-correlation between the position of the tip of the stick and the fingertip demonstrate that the role of closed-loop feedback changes with increased skill. Moreover, estimation of the neural latencies for stick balancing show that for a given stick length, the latency increases with skill level. It is suggested that the neural control for stick balancing involves a mechanism in which brief intervals of consciously generated, corrective movements alternate with longer intervals of prediction-free control. With learning the truncation of the Lèvy flight becomes better optimized for balance control and hence the time between successive conscious corrections increases. These observations provide the first evidence that changes in a Lèvy flight may have functional significance for the nervous system. This work has implications for the control of balancing problems ranging from falling in the elderly to the design of two-legged robots and earthquake proof buildings. Copyright 2004 American Institute of Physics

A Stochastic Water Balance Framework for Lowland Watersheds

NASA Astrophysics Data System (ADS)

Thompson, Sally; MacVean, Lissa; Sivapalan, Murugesu

2017-11-01

The water balance dynamics in lowland watersheds are influenced not only by local hydroclimatic controls on energy and water availability, but also by imports of water from the upstream watershed. These imports result in a stochastic extent of inundation in lowland watersheds that is determined by the local flood regime, watershed topography, and the rate of loss processes such as drainage and evaporation. Thus, lowland watershed water balances depend on two stochastic processes—rainfall and local inundation dynamics. Lowlands are high productivity environments that are disproportionately associated with urbanization, high productivity agriculture, biodiversity, and flood risk. Consequently, they are being rapidly altered by human development—generally with clear economic and social motivation—but also with significant trade-offs in ecosystem services provision, directly related to changes in the components and variability of the lowland water balance. We present a stochastic framework to assess the lowland water balance and its sensitivity to two common human interventions—replacement of native vegetation with alternative land uses, and construction of local flood protection levees. By providing analytical solutions for the mean and PDF of the water balance components, the proposed framework provides a mechanism to connect human interventions to hydrologic outcomes, and, in conjunction with ecosystem service production estimates, to evaluate trade-offs associated with lowland watershed development.

A new biarticular actuator design facilitates control of leg function in BioBiped3.

PubMed

Sharbafi, Maziar Ahmad; Rode, Christian; Kurowski, Stefan; Scholz, Dorian; Möckel, Rico; Radkhah, Katayon; Zhao, Guoping; Rashty, Aida Mohammadinejad; Stryk, Oskar von; Seyfarth, Andre

2016-07-01

Bioinspired legged locomotion comprises different aspects, such as (i) benefiting from reduced complexity control approaches as observed in humans/animals, (ii) combining embodiment with the controllers and (iii) reflecting neural control mechanisms. One of the most important lessons learned from nature is the significant role of compliance in simplifying control, enhancing energy efficiency and robustness against perturbations for legged locomotion. In this research, we investigate how body morphology in combination with actuator design may facilitate motor control of leg function. Inspired by the human leg muscular system, we show that biarticular muscles have a key role in balancing the upper body, joint coordination and swing leg control. Appropriate adjustment of biarticular spring rest length and stiffness can simplify the control and also reduce energy consumption. In order to test these findings, the BioBiped3 robot was developed as a new version of BioBiped series of biologically inspired, compliant musculoskeletal robots. In this robot, three-segmented legs actuated by mono- and biarticular series elastic actuators mimic the nine major human leg muscle groups. With the new biarticular actuators in BioBiped3, novel simplified control concepts for postural balance and for joint coordination in rebounding movements (drop jumps) were demonstrated and approved.

Human-Derived Disturbance Estimation and Compensation (DEC) Method Lends Itself to a Modular Sensorimotor Control in a Humanoid Robot.

PubMed

Lippi, Vittorio; Mergner, Thomas

2017-01-01

The high complexity of the human posture and movement control system represents challenges for diagnosis, therapy, and rehabilitation of neurological patients. We envisage that engineering-inspired, model-based approaches will help to deal with the high complexity of the human posture control system. Since the methods of system identification and parameter estimation are limited to systems with only a few DoF, our laboratory proposes a heuristic approach that step-by-step increases complexity when creating a hypothetical human-derived control systems in humanoid robots. This system is then compared with the human control in the same test bed, a posture control laboratory. The human-derived control builds upon the identified disturbance estimation and compensation (DEC) mechanism, whose main principle is to support execution of commanded poses or movements by compensating for external or self-produced disturbances such as gravity effects. In previous robotic implementation, up to 3 interconnected DEC control modules were used in modular control architectures separately for the sagittal plane or the frontal body plane and successfully passed balancing and movement tests. In this study we hypothesized that conflict-free movement coordination between the robot's sagittal and frontal body planes emerges simply from the physical embodiment, not necessarily requiring a full body control. Experiments were performed in the 14 DoF robot Lucy Posturob (i) demonstrating that the mechanical coupling from the robot's body suffices to coordinate the controls in the two planes when the robot produces movements and balancing responses in the intermediate plane, (ii) providing quantitative characterization of the interaction dynamics between body planes including frequency response functions (FRFs), as they are used in human postural control analysis, and (iii) witnessing postural and control stability when all DoFs are challenged together with the emergence of inter-segmental coordination in squatting movements. These findings represent an important step toward controlling in the robot in future more complex sensorimotor functions such as walking.

Human-Derived Disturbance Estimation and Compensation (DEC) Method Lends Itself to a Modular Sensorimotor Control in a Humanoid Robot

PubMed Central

Lippi, Vittorio; Mergner, Thomas

2017-01-01

The high complexity of the human posture and movement control system represents challenges for diagnosis, therapy, and rehabilitation of neurological patients. We envisage that engineering-inspired, model-based approaches will help to deal with the high complexity of the human posture control system. Since the methods of system identification and parameter estimation are limited to systems with only a few DoF, our laboratory proposes a heuristic approach that step-by-step increases complexity when creating a hypothetical human-derived control systems in humanoid robots. This system is then compared with the human control in the same test bed, a posture control laboratory. The human-derived control builds upon the identified disturbance estimation and compensation (DEC) mechanism, whose main principle is to support execution of commanded poses or movements by compensating for external or self-produced disturbances such as gravity effects. In previous robotic implementation, up to 3 interconnected DEC control modules were used in modular control architectures separately for the sagittal plane or the frontal body plane and successfully passed balancing and movement tests. In this study we hypothesized that conflict-free movement coordination between the robot's sagittal and frontal body planes emerges simply from the physical embodiment, not necessarily requiring a full body control. Experiments were performed in the 14 DoF robot Lucy Posturob (i) demonstrating that the mechanical coupling from the robot's body suffices to coordinate the controls in the two planes when the robot produces movements and balancing responses in the intermediate plane, (ii) providing quantitative characterization of the interaction dynamics between body planes including frequency response functions (FRFs), as they are used in human postural control analysis, and (iii) witnessing postural and control stability when all DoFs are challenged together with the emergence of inter-segmental coordination in squatting movements. These findings represent an important step toward controlling in the robot in future more complex sensorimotor functions such as walking. PMID:28951719

Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

NASA Technical Reports Server (NTRS)

Bloomberg, Jacob; Reschke, Millard; Mulavara, Ajitkumar; Wood, Scott; Serrador, Jorge; Fiedler, Matthew; Kofman, Igor; Peters, Brian T.; Cohen, Helen

2012-01-01

Crewmembers returning from long-duration space flight face significant challenges due to the microgravity-induced inappropriate adaptations in balance/ sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain s ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/portable providing imperceptible electrical stimulation to the balance organs of the human body. Stochastic resonance (SR) is a phenomenon whereby the response of a nonlinear system to a weak periodic input signal is optimized by the presence of a particular non-zero level of noise. This phenomenon of SR is based on the concept of maximizing the flow of information through a system by a non-zero level of noise. Application of imperceptible SR noise coupled with sensory input in humans has been shown to improve motor, cardiovascular, visual, hearing, and balance functions. SR increases contrast sensitivity and luminance detection; lowers the absolute threshold for tone detection in normal hearing individuals; improves homeostatic function in the human blood pressure regulatory system; improves noise-enhanced muscle spindle function; and improves detection of weak tactile stimuli using mechanical or electrical stimulation. SR noise has been shown to improve postural control when applied as mechanical noise to the soles of the feet, or when applied as electrical noise at the knee and to the back muscles.

Mapping of human genome raises serious issues for individual vs. corporate rights.

PubMed

Court, J

2001-01-01

Unrestricted corporate control of genetic technologies opens a pandora's box for the balance of power between individuals and corporations. This column provides an overview of the issues raised by commercialization of the human genome from a citizen advocate's perspective.

Using Motor Imagery to Study the Neural Substrates of Dynamic Balance

PubMed Central

Ferraye, Murielle Ursulla; Debû, Bettina; Heil, Lieke; Carpenter, Mark; Bloem, Bastiaan Roelof; Toni, Ivan

2014-01-01

This study examines the cerebral structures involved in dynamic balance using a motor imagery (MI) protocol. We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined swaying on a balance board along the sagittal plane to point a laser at target pairs of different sizes (small, large). We used a matched visual imagery (VI) control task and recorded imagery durations during scanning. MI and VI durations were differentially influenced by the sway accuracy requirement, indicating that MI of balance is sensitive to the increased motor control necessary to point at a smaller target. Compared to VI, MI of dynamic balance recruited additional cortical and subcortical portions of the motor system, including frontal cortex, basal ganglia, cerebellum and mesencephalic locomotor region, the latter showing increased effective connectivity with the supplementary motor area. The regions involved in MI of dynamic balance were spatially distinct but contiguous to those involved in MI of gait (Bakker et al., 2008; Snijders et al., 2011; Crémers et al., 2012), in a pattern consistent with existing somatotopic maps of the trunk (for balance) and legs (for gait). These findings validate a novel, quantitative approach for studying the neural control of balance in humans. This approach extends previous reports on MI of static stance (Jahn et al., 2004, 2008), and opens the way for studying gait and balance impairments in patients with neurodegenerative disorders. PMID:24663383

Using motor imagery to study the neural substrates of dynamic balance.

PubMed

Ferraye, Murielle Ursulla; Debû, Bettina; Heil, Lieke; Carpenter, Mark; Bloem, Bastiaan Roelof; Toni, Ivan

2014-01-01

This study examines the cerebral structures involved in dynamic balance using a motor imagery (MI) protocol. We recorded cerebral activity with functional magnetic resonance imaging while subjects imagined swaying on a balance board along the sagittal plane to point a laser at target pairs of different sizes (small, large). We used a matched visual imagery (VI) control task and recorded imagery durations during scanning. MI and VI durations were differentially influenced by the sway accuracy requirement, indicating that MI of balance is sensitive to the increased motor control necessary to point at a smaller target. Compared to VI, MI of dynamic balance recruited additional cortical and subcortical portions of the motor system, including frontal cortex, basal ganglia, cerebellum and mesencephalic locomotor region, the latter showing increased effective connectivity with the supplementary motor area. The regions involved in MI of dynamic balance were spatially distinct but contiguous to those involved in MI of gait (Bakker et al., 2008; Snijders et al., 2011; Crémers et al., 2012), in a pattern consistent with existing somatotopic maps of the trunk (for balance) and legs (for gait). These findings validate a novel, quantitative approach for studying the neural control of balance in humans. This approach extends previous reports on MI of static stance (Jahn et al., 2004, 2008), and opens the way for studying gait and balance impairments in patients with neurodegenerative disorders.

An optimal state estimation model of sensory integration in human postural balance

NASA Astrophysics Data System (ADS)

Kuo, Arthur D.

2005-09-01

We propose a model for human postural balance, combining state feedback control with optimal state estimation. State estimation uses an internal model of body and sensor dynamics to process sensor information and determine body orientation. Three sensory modalities are modeled: joint proprioception, vestibular organs in the inner ear, and vision. These are mated with a two degree-of-freedom model of body dynamics in the sagittal plane. Linear quadratic optimal control is used to design state feedback and estimation gains. Nine free parameters define the control objective and the signal-to-noise ratios of the sensors. The model predicts statistical properties of human sway in terms of covariance of ankle and hip motion. These predictions are compared with normal human responses to alterations in sensory conditions. With a single parameter set, the model successfully reproduces the general nature of postural motion as a function of sensory environment. Parameter variations reveal that the model is highly robust under normal sensory conditions, but not when two or more sensors are inaccurate. This behavior is similar to that of normal human subjects. We propose that age-related sensory changes may be modeled with decreased signal-to-noise ratios, and compare the model's behavior with degraded sensors against experimental measurements from older adults. We also examine removal of the model's vestibular sense, which leads to instability similar to that observed in bilateral vestibular loss subjects. The model may be useful for predicting which sensors are most critical for balance, and how much they can deteriorate before posture becomes unstable.

Stabilization of a three-dimensional limit cycle walking model through step-to-step ankle control.

PubMed

Kim, Myunghee; Collins, Steven H

2013-06-01

Unilateral, below-knee amputation is associated with an increased risk of falls, which may be partially related to a loss of active ankle control. If ankle control can contribute significantly to maintaining balance, even in the presence of active foot placement, this might provide an opportunity to improve balance using robotic ankle-foot prostheses. We investigated ankle- and hip-based walking stabilization methods in a three-dimensional model of human gait that included ankle plantarflexion, ankle inversion-eversion, hip flexion-extension, and hip ad/abduction. We generated discrete feedback control laws (linear quadratic regulators) that altered nominal actuation parameters once per step. We used ankle push-off, lateral ankle stiffness and damping, fore-aft foot placement, lateral foot placement, or all of these as control inputs. We modeled environmental disturbances as random, bounded, unexpected changes in floor height, and defined balance performance as the maximum allowable disturbance value for which the model walked 500 steps without falling. Nominal walking motions were unstable, but were stabilized by all of the step-to-step control laws we tested. Surprisingly, step-by-step modulation of ankle push-off alone led to better balance performance (3.2% leg length) than lateral foot placement (1.2% leg length) for these control laws. These results suggest that appropriate control of robotic ankle-foot prosthesis push-off could make balancing during walking easier for individuals with amputation.

Learning an Intermittent Control Strategy for Postural Balancing Using an EMG-Based Human-Computer Interface

PubMed Central

Asai, Yoshiyuki; Tateyama, Shota; Nomura, Taishin

2013-01-01

It has been considered that the brain stabilizes unstable body dynamics by regulating co-activation levels of antagonist muscles. Here we critically reexamined this established theory of impedance control in a postural balancing task using a novel EMG-based human-computer interface, in which subjects were asked to balance a virtual inverted pendulum using visual feedback information on the pendulum's position. The pendulum was actuated by a pair of antagonist joint torques determined in real-time by activations of the corresponding pair of antagonist ankle muscles of subjects standing upright. This motor-task raises a frustrated environment; a large feedback time delay in the sensorimotor loop, as a source of instability, might favor adopting the non-reactive, preprogrammed impedance control, but the ankle muscles are relatively hard to co-activate, which hinders subjects from adopting the impedance control. This study aimed at discovering how experimental subjects resolved this frustrated environment through motor learning. One third of subjects adapted to the balancing task in a way of the impedance-like control. It was remarkable, however, that the majority of subjects did not adopt the impedance control. Instead, they acquired a smart and energetically efficient strategy, in which two muscles were inactivated simultaneously at a sequence of optimal timings, leading to intermittent appearance of periods of time during which the pendulum was not actively actuated. Characterizations of muscle inactivations and the pendulum¡Çs sway showed that the strategy adopted by those subjects was a type of intermittent control that utilizes a stable manifold of saddle-type unstable upright equilibrium that appeared in the state space of the pendulum when the active actuation was turned off. PMID:23717398

HIF isoforms in the skin differentially regulate systemic arterial pressure

PubMed Central

Cowburn, Andrew S.; Takeda, Norihiko; Boutin, Adam T.; Kim, Jung-Whan; Sterling, Jane C.; Nakasaki, Manando; Southwood, Mark; Goldrath, Ananda W.; Jamora, Colin; Nizet, Victor; Chilvers, Edwin R.; Johnson, Randall S.

2013-01-01

Vascular flow through tissues is regulated via a number of homeostatic mechanisms. Localized control of tissue blood flow, or autoregulation, is a key factor in regulating tissue perfusion and oxygenation. We show here that the net balance between two hypoxia-inducible factor (HIF) transcription factor isoforms, HIF-1α and HIF-2α, is an essential mechanism regulating both local and systemic blood flow in the skin of mice. We also show that balance of HIF isoforms in keratinocyte-specific mutant mice affects thermal adaptation, exercise capacity, and systemic arterial pressure. The two primary HIF isoforms achieve these effects in opposing ways that are associated with HIF isoform regulation of nitric oxide production. We also show that a correlation exists between altered levels of HIF isoforms in the skin and the degree of idiopathic hypertension in human subjects. Thus, the balance between HIF-1α and HIF-2α expression in keratinocytes is a control element of both tissue perfusion and systemic arterial pressure, with potential implications in human hypertension. PMID:24101470

Design, implementation and stabilization of a Bipedal robot

NASA Astrophysics Data System (ADS)

Nath, Alok; Das, Goutam; Mallick, Anik; Chowdhury, Shovan

2017-12-01

In this paper, we have presented the mechanical design and fabrication of a Bipedal walking robot as well as control strategies to be implemented for walking and balance recovery. For this robot, we considered Six Degree of Freedom (D.O.P) in the lower body one at each hip, one at each knee and one at each ankle. Each degree of freedom is powered by a RC servo motor and this robot is controlled by Arduino Mega 2560 micro controller. By balancing center of mass (C.O.M) it walks in rhythmic way as like as human one.

Phosphate toxicity: new insights into an old problem

PubMed Central

RAZZAQUE, M. Shawkat

2011-01-01

Phosphorus is an essential nutrient required for critical biological reactions that maintain the normal homoeostatic control of the cell. This element is an important component of different cellular structures, including nucleic acids and cell membranes. Adequate phosphorus balance is vital for maintaining basic cellular functions, ranging from energy metabolism to cell signalling. In addition, many intracellular pathways utilize phosphate ions for important cellular reactions; therefore, homoeostatic control of phosphate is one of the most delicate biological regulations. Impaired phosphorus balance can affect the functionality of almost every human system, including musculoskeletal and cardiovascular systems, ultimately leading to an increase in morbidity and mortality of the affected patients. Human and experimental studies have found that delicate balance among circulating factors, like vitamin D, PTH (parathyroid hormone) and FGF23 (fibroblast growth factor 23), are essential for regulation of physiological phosphate balance. Dysregulation of these factors, either alone or in combination, can induce phosphorus imbalance. Recent studies have shown that suppression of the FGF23–klotho system can lead to hyperphosphataemia with extensive tissue damage caused by phosphate toxicity. The cause and consequences of phosphate toxicity will be briefly summarized in the present review. PMID:20958267

Phosphate toxicity: new insights into an old problem.

PubMed

Razzaque, M Shawkat

2011-02-01

Phosphorus is an essential nutrient required for critical biological reactions that maintain the normal homoeostatic control of the cell. This element is an important component of different cellular structures, including nucleic acids and cell membranes. Adequate phosphorus balance is vital for maintaining basic cellular functions, ranging from energy metabolism to cell signalling. In addition, many intracellular pathways utilize phosphate ions for important cellular reactions; therefore, homoeostatic control of phosphate is one of the most delicate biological regulations. Impaired phosphorus balance can affect the functionality of almost every human system, including musculoskeletal and cardiovascular systems, ultimately leading to an increase in morbidity and mortality of the affected patients. Human and experimental studies have found that delicate balance among circulating factors, like vitamin D, PTH (parathyroid hormone) and FGF23 (fibroblast growth factor 23), are essential for regulation of physiological phosphate balance. Dysregulation of these factors, either alone or in combination, can induce phosphorus imbalance. Recent studies have shown that suppression of the FGF23-klotho system can lead to hyperphosphataemia with extensive tissue damage caused by phosphate toxicity. The cause and consequences of phosphate toxicity will be briefly summarized in the present review.

Counter-balanced, multiple cable construction crane

NASA Astrophysics Data System (ADS)

Mikulas, Martin M., Jr.; Yang, Li-Farn

1991-11-01

The invention is a counter-balanced, multiple cable construction crane. The apparatus for hoisting payloads comprises a crane having a lifting means, the lifting means comprising an end effector means and three suspension means or cables. One end of each cable attaches to a different winding means located on the lifting means, and the other end of each cable attaches to a different point on the end effector, such that the three cables have a theoretical point of convergence with this point corresponding to the center of mass of the payload. Three controls command rotation of the winding means to a predetermined position. Accordingly, the crane provides precise and autonomous positioning of the payload without human guidance. The crane further comprises a counter-balancing means. Two controls position the counter-balancing means to offset the overturning moment which arises during the lifting of heavy payloads.

Counter-balanced, multiple cable construction crane

NASA Astrophysics Data System (ADS)

Mikulas, Martin M., Jr.; Yang, Li-Farn

1993-10-01

The invention is a counter-balanced, multiple cable construction crane. The apparatus for hoisting payloads comprises a crane having a lifting means, the lifting means comprising an end effector means and three suspension means or cables. One end of each cable attaches to a different winding means located on the lifting means, and the other end of each cable attaches to a different point on the end effector, such that the three cables have a theoretical point of convergence with this point corresponding to the center of mass of the payload. Three controls command rotation of the winding means to a predetermined position. Accordingly, the crane provides precise and autonomous positioning of the payload without human guidance. The crane further comprises a counter-balancing means. Two controls position the counter-balancing means to offset the overturning moment which arises during the lifting of heavy payloads.

Counter-balanced, multiple cable construction crane

NASA Technical Reports Server (NTRS)

Mikulas, Martin M., Jr. (Inventor); Yang, Li-Farn (Inventor)

1993-01-01

The invention is a counter-balanced, multiple cable construction crane. The apparatus for hoisting payloads comprises a crane having a lifting means, the lifting means comprising an end effector means and three suspension means or cables. One end of each cable attaches to a different winding means located on the lifting means, and the other end of each cable attaches to a different point on the end effector, such that the three cables have a theoretical point of convergence with this point corresponding to the center of mass of the payload. Three controls command rotation of the winding means to a predetermined position. Accordingly, the crane provides precise and autonomous positioning of the payload without human guidance. The crane further comprises a counter-balancing means. Two controls position the counter-balancing means to offset the overturning moment which arises during the lifting of heavy payloads.

Evolutionary Response to Human Infectious Diseases

ERIC Educational Resources Information Center

Armelagos, George J.; Dewey, John R.

1970-01-01

Gives an overview of human history, relating cultural changes with resulting changes in population density and in ecological balance to patterns of infectious diseases in man. Discusses mechanisms of evolution of resistance. Suggests that in populations where infectious diseases can be controlled, attention should shift to degenerative diseases…

Step-to-Step Ankle Inversion/Eversion Torque Modulation Can Reduce Effort Associated with Balance.

PubMed

Kim, Myunghee; Collins, Steven H

2017-01-01

Below-knee amputation is associated with higher energy expenditure during walking, partially due to difficulty maintaining balance. We previously found that once-per-step push-off work control can reduce balance-related effort, both in simulation and in experiments with human participants. Simulations also suggested that changing ankle inversion/eversion torque on each step, in response to changes in body state, could assist with balance. In this study, we investigated the effects of ankle inversion/eversion torque modulation on balance-related effort among amputees ( N = 5) using a multi-actuated ankle-foot prosthesis emulator. In stabilizing conditions, changes in ankle inversion/eversion torque were applied so as to counteract deviations in side-to-side center-of-mass acceleration at the moment of intact-limb toe off; higher acceleration toward the prosthetic limb resulted in a corrective ankle inversion torque during the ensuing stance phase. Destabilizing controllers had the opposite effect, and a zero gain controller made no changes to the nominal inversion/eversion torque. To separate the balance-related effects of step-to-step control from the potential effects of changes in average mechanics, average ankle inversion/eversion torque and prosthesis work were held constant across conditions. High-gain stabilizing control lowered metabolic cost by 13% compared to the zero gain controller ( p = 0.05). We then investigated individual responses to subject-specific stabilizing controllers following an enforced exploration period. Four of five participants experienced reduced metabolic rate compared to the zero gain controller (-15, -14, -11, -6, and +4%) an average reduction of 9% ( p = 0.05). Average prosthesis mechanics were unchanged across all conditions, suggesting that improvements in energy economy might have come from changes in step-to-step corrections related to balance. Step-to-step modulation of inversion/eversion torque could be used in new, active ankle-foot prostheses to reduce walking effort associated with maintaining balance.

Control of thermal balance by a liquid circulating garment based on a mathematical representation of the human thermoregulatory system. Ph.D. Thesis - California Univ., Berkeley

NASA Technical Reports Server (NTRS)

Kuznetz, L. H.

1976-01-01

Test data and a mathematical model of the human thermoregulatory system were used to investigate control of thermal balance by means of a liquid circulating garment (LCG). The test data were derived from five series of experiments in which environmental and metabolic conditions were varied parametrically as a function of several independent variables, including LCG flowrate, LCG inlet temperature, net environmental heat exchange, surrounding gas ventilation rate, ambient pressure, metabolic rate, and subjective/obligatory cooling control. The resultant data were used to relate skin temperature to LCG water temperature and flowrate, to assess a thermal comfort band, to demonstrate the relationship between metabolic rate and LCG heat dissipation, and so forth. The usefulness of the mathematical model as a tool for data interpretation and for generation of trends and relationships among the various physiological parameters was also investigated and verified.

Fluid Intelligence as a Mediator of the Relationship between Executive Control and Balanced Time Perspective.

PubMed

Zajenkowski, Marcin; Stolarski, Maciej; Witowska, Joanna; Maciantowicz, Oliwia; Łowicki, Paweł

2016-01-01

This study examined the cognitive foundations of the balanced time perspective (BTP) proposed by Zimbardo and Boyd (1999). Although BTP is defined as the mental ability to switch effectively between different temporal perspectives, its connection with cognitive functioning has not yet been established. We addressed this by exploring the relationships between time perspectives and both fluid intelligence (measured with Raven's and Cattell's tests) and executive control (Go/No-go and anti-saccade tasks). An investigation conducted among Polish adults ( N = 233) revealed that more balanced TP profile was associated with higher fluid intelligence, and higher executive control. Moreover, we found that the relationship between executive control and BTP was completely mediated by fluid intelligence with the effect size (the ratio of the indirect effect to the total effect) of 0.75, which suggests that cognitive abilities play an important role in adoption of temporal balance. The findings have relevance to time perspective theory as they provide valuable insight into the mechanisms involved in assigning human experience to certain time frames.

Disruptions in Energy Balance: Does Nature overcome Nurture?

PubMed Central

Fernández, José R.; Casazza, Krista; Divers, Jasmin; López-Alarcón, Mardya

2008-01-01

Fat accumulation, in general, is the result of a breakdown in the homeostatic regulation of energy balance. Although, the specific factors influencing the disruption of energy balance and why these factors affect individuals differently are not completely understood, numerous studies have identified multiple contributors. Environmental components influence food acquisition, eating, and lifestyle habits. However, the variability in obesity-related outcomes observed among individuals placed in similar controlled environments support the notion that genetic components also wield some control. Multiple genetic regions have been associated with measures related to energy balance; however, the replication of these genetic contributors to energy intake and energy expenditure in humans is relatively small perhaps because of the heterogeneity of human populations. Genetic tools such as genetic admixture account for individual’s genetic background in gene association studies, reducing the confounding effect of population stratification, and promise to be a relevant tool on the identification of genetic contributions to energy balance, particularly among individuals of diverse racial/ethnic backgrounds. Although it has been recognized that genes are expressed according to environmental influences, the search toward the understanding of nature and nurture in obesity will require the detailed study of the effect of genes under diverse physiologic and behavioral environments. It is evident that more research is needed to elucidate the methodological and statistical issues that underlie the interactions between genes and environments in obesity and its related comorbidities. PMID:18096193

Sex And People.

ERIC Educational Resources Information Center

Jones, Kenneth L.; And Others

This textbook for the college student emphasizes human sexuality as a part of the whole human life experience and contains a balance of biological, psychological, and sociological material. In 16 chapters the following topics are covered: (1) sex and society; (2) historical and cultural perspectives; (3) glandular control of sexual physiology; (4)…

Analysis of tasks for dynamic man/machine load balancing in advanced helicopters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jorgensen, C.C.

1987-10-01

This report considers task allocation requirements imposed by advanced helicopter designs incorporating mixes of human pilots and intelligent machines. Specifically, it develops an analogy between load balancing using distributed non-homogeneous multiprocessors and human team functions. A taxonomy is presented which can be used to identify task combinations likely to cause overload for dynamic scheduling and process allocation mechanisms. Designer criteria are given for function decomposition, separation of control from data, and communication handling for dynamic tasks. Possible effects of n-p complete scheduling problems are noted and a class of combinatorial optimization methods are examined.

[Kidney, Fluid, and Acid-Base Balance].

PubMed

Shioji, Naohiro; Hayashi, Masao; Morimatsu, Hiroshi

2016-05-01

Kidneys play an important role to maintain human homeostasis. They contribute to maintain body fluid, electrolytes, and acid-base balance. Especially in fluid control, we, physicians can intervene body fluid balance using fluid resuscitation and diuretics. In recent years, one type of fluid resuscitation, hydroxyl ethyl starch has been extensively studied in the field of intensive care. Although their effects on fluid resuscitation are reasonable, serious complications such as kidney injury requiring renal replacement therapy occur frequently. Now we have to pay more attention to this important complication. Another topic of fluid management is tolvaptan, a selective vasopressin-2 receptor antagonist Recent randomized trial suggested that tolvaptan has a similar supportive effect for fluid control and more cost effective compared to carperitide. In recent years, Stewart approach is recognized as one important tool to assess acid-base balance in critically ill patients. This approach has great value, especially to understand metabolic components in acid-base balance. Even for assessing the effects of kidneys on acid-base balance, this approach gives us interesting insight. We should appropriately use this new approach to treat acid-base abnormality in critically ill patients.

Lunar Balance and Locomotion

NASA Technical Reports Server (NTRS)

Paloski, William H.

2008-01-01

Balance control and locomotor patterns were altered in Apollo crewmembers on the lunar surface, owing, presumably, to a combination of sensory-motor adaptation during transit and lunar surface operations, decreased environmental affordances associated with the reduced gravity, and restricted joint mobility as well as altered center-of-gravity caused by the EVA pressure suits. Dr. Paloski will discuss these factors, as well as the potential human and mission impacts of falls and malcoordination during planned lunar sortie and outpost missions. Learning objectives: What are the potential impacts of postural instabilities on the lunar surface? CME question: What factors affect balance control and gait stability on the moon? Answer: Sensory-motor adaptation to the lunar environment, reduced mechanical and visual affordances, and altered biomechanics caused by the EVA suit.

Body mass, energy intake, and water consumption of rats and humans during space flight

NASA Technical Reports Server (NTRS)

Wade, C. E.; Miller, M. M.; Baer, L. A.; Moran, M. M.; Steele, M. K.; Stein, T. P.

2002-01-01

Alteration of metabolism has been suggested as a major limiting factor to long-term space flight. In humans and primates, a negative energy balance has been reported. The metabolic response of rats to space flight has been suggested to result in a negative energy balance. We hypothesized that rats flown in space would maintain energy balance as indicated by maintenance of caloric intake and body mass gain. Further, the metabolism of the rat would be similar to that of laboratory-reared animals. We studied the results from 15 space flights lasting 4 to 19 d. There was no difference in average body weight (206 +/- 13.9 versus 206 +/- 14.8 g), body weight gain (5.8 +/- 0.48 versus 5.9 +/- 0.56 g/d), caloric intake (309 +/- 21.0 versus 309 +/- 20.1 kcal/kg of body mass per day), or water intake (200 +/- 8.6 versus 199 +/- 9.3 mL/kg of body mass per day) between flight and ground control animals. Compared with standard laboratory animals of similar body mass, no differences were noted. The observations suggested that the negative balance observed in humans and non-human primates may be due to other factors in the space-flight environment.

Balance and its Clinical Assessment in Older Adults – A Review

PubMed Central

Nnodim, Joseph O.; Yung, Raymond L.

2016-01-01

Background Human beings rely on multiple systems to maintain their balance as they perform their activities of daily living. These systems may be undermined functionally by both disease and the normal aging process. Balance impairment is associated with increased fall risk. Purpose This paper examines the dynamic formulation of balance as activity and reviews the biological mechanisms for its control. A “minimal-technology” scheme for its clinical evaluation in the ambulatory care setting is proposed. Methods The PubMed, Scopus and CINAHL databases were searched for relevant articles using the following terms in combination with balance: aging, impairment, control mechanisms, clinical assessment. Only articles which describe test procedures, their psychometrics and rely exclusively on equipment found in a regular physician office were reviewed. Results Human bipedal stance and gait are inherently low in stability. Accordingly, an elaborate sensory apparatus comprising visual, vestibular and proprioceptive elements, constantly monitors the position and movement of the body in its environment and sends signals to the central nervous system. The sensory inputs are processed and motor commands are generated. In response to efferent signals, the musculoskeletal system moves the body as is necessary to maintain or regain balance. The combination of senescent decline in organ function and the higher prevalence of diseases of the balance control systems in older adults predisposes this population subset to balance impairment. Older adults with balance impairment are likely to present with “dizziness”. The history should concentrate on the first experience, with an attempt made to categorize it as a Drachman type. Since the symptomatology is often vague, several of the recommended physical tests are provocative maneuvers aimed at reproducing the patient’s complaint. Well-validated questionnaires are available for evaluating the impact of “dizziness” on various domains of patient’s lives, including their fear of falling. Aspects of a good history and physical examination not otherwise addressed to balance function, such as medications review and cognitive assessment, also yield information that contributes to a better understanding of the patient’s complaint. Ordinal scales, which are aggregates of functional performance tests, enable detailed quantitative assessments of balance activity. Conclusion The integrity of balance function is essential for activities of daily living efficacy. Its deterioration with aging and disease places older adults at increased risk of falls and dependency. Balance can be effectively evaluated in the ambulatory care setting, using a combination of scalar questionnaires, dedicated history-taking and physical tests that do not require sophisticated instrumentation. PMID:26942231

A model of neuro-musculo-skeletal system for human locomotion under position constraint condition.

PubMed

Ni, Jiangsheng; Hiramatsu, Seiji; Kato, Atsuo

2003-08-01

The human locomotion was studied on the basis of the interaction of the musculo-skeletal system, the neural system and the environment. A mathematical model of human locomotion under position constraint condition was established. Besides the neural rhythm generator, the posture controller and the sensory system, the environment feedback controller and the stability controller were taken into account in the model. The environment feedback controller was proposed for two purposes, obstacle avoidance and target position control of the swing foot. The stability controller was proposed to imitate the self-balancing ability of a human body and improve the stability of the model. In the stability controller, the ankle torque was used to control the velocity of the body gravity center. A prediction control algorithm was applied to calculate the torque magnitude of the stability controller. As an example, human stairs climbing movement was simulated and the results were given. The simulation result proved that the mathematical modeling of the task was successful.

Accuracy of force and center of pressure measures of the Wii Balance Board.

PubMed

Bartlett, Harrison L; Ting, Lena H; Bingham, Jeffrey T

2014-01-01

The Nintendo Wii Balance Board (WBB) is increasingly used as an inexpensive force plate for assessment of postural control; however, no documentation of force and COP accuracy and reliability is publicly available. Therefore, we performed a standard measurement uncertainty analysis on 3 lightly and 6 heavily used WBBs to provide future users with information about the repeatability and accuracy of the WBB force and COP measurements. Across WBBs, we found the total uncertainty of force measurements to be within ± 9.1N, and of COP location within ± 4.1mm. However, repeatability of a single measurement within a board was better (4.5 N, 1.5mm), suggesting that the WBB is best used for relative measures using the same device, rather than absolute measurement across devices. Internally stored calibration values were comparable to those determined experimentally. Further, heavy wear did not significantly degrade performance. In combination with prior evaluation of WBB performance and published standards for measuring human balance, our study provides necessary information to evaluate the use of the WBB for analysis of human balance control. We suggest the WBB may be useful for low-resolution measurements, but should not be considered as a replacement for laboratory-grade force plates. Published by Elsevier B.V.

Accuracy of force and center of pressure measures of the Wii Balance Board

PubMed Central

Bartlett, Harrison L.; Ting, Lena H.; Bingham, Jeffrey T.

2013-01-01

The Nintendo Wii Balance Board (WBB) is increasingly used as an inexpensive force plate for assessment of postural control; however, no documentation of force and COP accuracy and reliability is publicly available. Therefore, we performed a standard measurement uncertainty analysis on 3 lightly and 6 heavily used WBBs to provide future users with information about the repeatability and accuracy of the WBB force and COP measurements. Across WBBs, we found the total uncertainty of force measurements to be within ±9.1 N, and of COP location within ±4.1 mm. However, repeatability of a single measurement within a board was better (4.5 N, 1.5 mm), suggesting that the WBB is best used for relative measures using the same device, rather than absolute measurement across devices. Internally stored calibration values were comparable to those determined experimentally. Further, heavy wear did not significantly degrade performance. In combination with prior evaluation of WBB performance and published standards for measuring human balance, our study provides necessary information to evaluate the use of the WBB for analysis of human balance control. We suggest the WBB may be useful for low-resolution measurements, but should not be considered as a replacement for laboratory-grade force plates. PMID:23910725

An Integrated Gait and Balance Analysis System to Define Human Locomotor Control

DTIC Science & Technology

2016-04-29

common in the “real-world”. Furthermore, BCI controllers need some sort of direct link into neural signals and this requires invasive surgery and...L. J., Simon, A. M., Young, A. J., Lipschutz, R. D., Finucane, S. B., Smith, D. G., & Kuiken, T. A. (2013). Robotic leg control with EMG decoding in

Effects of Gravity on Cells, Tissues, and Organisms: Their Implications on Habitat and Human Support in Microgravity

NASA Technical Reports Server (NTRS)

Kizito, John

2004-01-01

This presentation will demonstrate that gravity plays a major role in advanced human life support in a closed habitat. The examples include, but are not limited to, control of purity in drinking water supplies (application of biocides), control of urine in space rodent habitats and operation of space septic tanks (waste management). Our goal is to understand and determine possible mechanisms that describe the process by which cells anchor to a substrate to form dynamic, vibrant communities of cells which influence human health in absence of gravity. The balance of all forces (mechanotransduction) acting on a cell will determine whether a cell thrives and multiplies or dies in a process called apoptosis and/or necrosis. The balance of forces are tightly coupled to the transport of nutrients and metabolic products (biochemotransduction) to and from the cell interface. We will highlight our effort to improve astronaut health by showing that microgravity life support systems have to be designed differently from those on Earth.

Physical and sporting activities improve vestibular afferent usage and balance in elderly human subjects.

PubMed

Gauchard, G C; Jeandel, C; Perrin, P P

2001-01-01

Ageing is associated with a reduction in balance, in particular through dysfunction of each level of postural control, which results in an increased risk of falling. Conversely, the practice of physical activities has been shown to modulate postural control in elderly people. This study examined the potential positive effects of two types of regular physical and sporting activities on vestibular information and their relation to posture. Gaze and postural stabilisation was evaluated by caloric and rotational vestibular tests on 18 healthy subjects over the age of 60 who regularly practised low-energy or bioenergetic physical activities and on 18 controls of a similar age who only walked on a regular basis. These subjects were also submitted to static and dynamic posturographic tests. The control group displayed less balance control, with a lower vestibular sensitivity and a relatively high dependency on vision compared to the group practising low-energy physical activities, which had better postural control with good vestibular sensitivity and less dependency on vision. The postural control and vestibular sensitivity of subjects practising bioenergetic activities was average, and required higher visual afferent contribution. Low-energy exercises, already shown to have the most positive impact on balance control by relying more on proprioception, also appear to develop or maintain a high level of vestibular sensitivity allowing elderly people practising such exercises to reduce the weight of vision. Copyright 2001 S. Karger AG, Basel

Advanced robot locomotion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neely, Jason C.; Sturgis, Beverly Rainwater; Byrne, Raymond Harry

This report contains the results of a research effort on advanced robot locomotion. The majority of this work focuses on walking robots. Walking robot applications include delivery of special payloads to unique locations that require human locomotion to exo-skeleton human assistance applications. A walking robot could step over obstacles and move through narrow openings that a wheeled or tracked vehicle could not overcome. It could pick up and manipulate objects in ways that a standard robot gripper could not. Most importantly, a walking robot would be able to rapidly perform these tasks through an intuitive user interface that mimics naturalmore » human motion. The largest obstacle arises in emulating stability and balance control naturally present in humans but needed for bipedal locomotion in a robot. A tracked robot is bulky and limited, but a wide wheel base assures passive stability. Human bipedal motion is so common that it is taken for granted, but bipedal motion requires active balance and stability control for which the analysis is non-trivial. This report contains an extensive literature study on the state-of-the-art of legged robotics, and it additionally provides the analysis, simulation, and hardware verification of two variants of a proto-type leg design.« less

Roles of the Declive, Folium, and Tuber Cerebellar Vermian Lobules in Sportspeople

PubMed Central

Park, In Sung; Lee, Nam Joon

2018-01-01

The cerebellum plays vital roles in balance control and motor learning, including in saccadic adaptation and coordination. It consists of the vermis and two hemispheres and is anatomically separated into ten lobules that are designated as I–X. Although neuroimaging and clinical studies suggest that functions are compartmentalized within the cerebellum, the function of each cerebellar lobule is not fully understood. Electrophysiological and lesion studies in animals as well as neuroimaging and lesion studies in humans have revealed that vermian lobules VI and VII (declive, folium, and tuber) are critical for controlling postural balance, saccadic eye movements, and coordination. In addition, recent structural magnetic resonance imaging studies have revealed that these lobules are larger in elite basketball and short-track speed skaters. Furthermore, in female short-track speed skaters, the volume of this region is significantly correlated with static balance. This article reviews the function of vermian lobules VI and VII, focusing on the control of balance, eye movements, and coordination including coordination between the eyes and hands and bimanual coordination. PMID:29141275

Reliance on habits at the expense of goal-directed control following dopamine precursor depletion.

PubMed

de Wit, Sanne; Standing, Holly R; Devito, Elise E; Robinson, Oliver J; Ridderinkhof, K Richard; Robbins, Trevor W; Sahakian, Barbara J

2012-01-01

Dopamine is well known to play an important role in learning and motivation. Recent animal studies have implicated dopamine in the reinforcement of stimulus-response habits, as well as in flexible, goal-directed action. However, the role of dopamine in human action control is still not well understood. We present the first investigation of the effect of reducing dopamine function in healthy volunteers on the balance between habitual and goal-directed action control. The dietary intervention of acute dietary phenylalanine and tyrosine depletion (APTD) was adopted to study the effects of reduced global dopamine function on action control. Participants were randomly assigned to either the APTD or placebo group (ns = 14) to allow for a between-subjects comparison of performance on a novel three-stage experimental paradigm. In the initial learning phase, participants learned to respond to different stimuli in order to gain rewarding outcomes. Subsequently, an outcome-devaluation test and a slips-of-action test were conducted to assess whether participants were able to flexibly adjust their behaviour to changes in the desirability of the outcomes. APTD did not prevent stimulus-response learning, nor did we find evidence for impaired response-outcome learning in the subsequent outcome-devaluation test. However, when goal-directed and habitual systems competed for control in the slips-of-action test, APTD tipped the balance towards habitual control. These findings were restricted to female volunteers. We provide direct evidence that the balance between goal-directed and habitual control in humans is dopamine dependent. The results are discussed in light of gender differences in dopamine function and psychopathologies.

Individual differences in brainstem and basal ganglia structure predict postural control and balance loss in young and older adults.

PubMed

Boisgontier, Matthieu P; Cheval, Boris; Chalavi, Sima; van Ruitenbeek, Peter; Leunissen, Inge; Levin, Oron; Nieuwboer, Alice; Swinnen, Stephan P

2017-02-01

It remains unclear which specific brain regions are the most critical for human postural control and balance, and whether they mediate the effect of age. Here, associations between postural performance and corticosubcortical brain regions were examined in young and older adults using multiple structural imaging and linear mixed models. Results showed that of the regions involved in posture, the brainstem was the strongest predictor of postural control and balance: lower brainstem volume predicted larger center of pressure deviation and higher odds of balance loss. Analyses of white and gray matter in the brainstem showed that the pedunculopontine nucleus area appeared to be critical for postural control in both young and older adults. In addition, the brainstem mediated the effect of age on postural control, underscoring the brainstem's fundamental role in aging. Conversely, lower basal ganglia volume predicted better postural performance, suggesting an association between greater neural resources in the basal ganglia and greater movement vigor, resulting in exaggerated postural adjustments. Finally, results showed that practice, shorter height and heavier weight (i.e., higher body mass index), higher total physical activity, and larger ankle active (but not passive) range of motion were predictive of more stable posture, irrespective of age. Copyright © 2016 Elsevier Inc. All rights reserved.

Position versus force control: using the 2-DOF robotic ankle trainer to assess ankle's motor control.

PubMed

Farjadian, Amir B; Nabian, Mohsen; Hartman, Amber; Corsino, Johnathan; Mavroidis, Constantinos; Holden, Maureen K

2014-01-01

An estimated of 2,000,000 acute ankle sprains occur annually in the United States. Furthermore, ankle disabilities are caused by neurological impairments such as traumatic brain injury, cerebral palsy and stroke. The virtually interfaced robotic ankle and balance trainer (vi-RABT) was introduced as a cost-effective platform-based rehabilitation robot to improve overall ankle/balance strength, mobility and control. The system is equipped with 2 degrees of freedom (2-DOF) controlled actuation along with complete means of angle and torque measurement mechanisms. Vi-RABT was used to assess ankle strength, flexibility and motor control in healthy human subjects, while playing interactive virtual reality games on the screen. The results suggest that in the task with 2-DOF, subjects have better control over ankle's position vs. force.

The influence of hydro-ethanolic extract of Portulaca oleracea L. on Th1/Th2 balance in isolated human lymphocytes.

PubMed

Askari, Vahid Reza; Rezaee, Seyed Abdolrahim; Abnous, Khalil; Iranshahi, Mehrdad; Boskabady, Mohammad Hossein

2016-12-24

The anti-inflammatory and anti-oxidants activity of Portulaca oleracea L. (P. oleracea) were mentioned in traditional texts. In previous studies, different anti-inflammatory and anti-oxidant effects of P. oleracea were demonstrated. However, the mechanism of action and immunomodulatory property of this plant are greatly unknown. In the present study, the effect of the extract of this plant on IL-4, IL10, IFN-γ and T helper (h)1/Th2 balance in non-stimulated and stimulated human lymphocytes was examined. The effect of three concentrations (160, 40 and 10µg/ml) of P. oleracea or dexamethasone were evaluated on percentage of cell proliferation and nitric oxide (NO) production as well as secretion of cytokines (IL-4, IL10 and IFN-γ) in PHA-stimulated and non-stimulated lymphocytes, and compared to control and dexamethasone as positive control (n=15 for each group). In stimulated cells, dexamethasone significantly inhibited the percentage of cell proliferation, NO production, and secretion of cytokines in comparison to control group (P<0.001 for all cases). The percentage of cell proliferation, NO production, and secretion of cytokines were significantly decreased while Th1/Th2 (IFN-γ/IL-4) and Treg/Th2 (IL-10/IL-4) balances significantly enhanced in treated groups with all three concentrations of extract compared to control group (P<0.001 for all cases). The effect of all concentrations of the extract on cell proliferation, NO production and secretion of cytokines as well as Treg/Th2 balance were significantly lower than dexamethasone (P<0.001 for all cases), but Th1/Th2 ratio obtained in the presence of only low extract concentration was lower than dexamethasone (P<0.01). Different concentrations of extract promoted Th1/Th2 and Treg/Th2 balances which may suggest the therapeutic value of the plant in inflammatory disease associated with decreased Th1/Th2 balance such as asthma or cancers. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Higher Balance Task Demands are Associated with an Increase in Individual Alpha Peak Frequency

PubMed Central

Hülsdünker, Thorben; Mierau, Andreas; Strüder, Heiko K.

2016-01-01

Balance control is fundamental for most daily motor activities, and its impairment is associated with an increased risk of falling. Growing evidence suggests the human cortex is essentially contributing to the control of standing balance. However, the exact mechanisms remain unclear and need further investigation. In a previous study, we introduced a new protocol to identify electrocortical activity associated with performance of different continuous balance tasks with the eyes opened. The aim of this study was to extend our previous results by investigating the individual alpha peak frequency (iAPF), a neurophysiological marker of thalamo-cortical information transmission, which remained unconsidered so far in balance research. Thirty-seven subjects completed nine balance tasks varying in surface stability and base of support. Electroencephalography (EEG) was recorded from 32 scalp locations throughout balancing with the eyes closed to ensure reliable identification of the iAPF. Balance performance was quantified as the sum of anterior-posterior and medio-lateral movements of the supporting platform. The iAPF, as well as power in the theta, lower alpha and upper alpha frequency bands were determined for each balance task after applying an ICA-based artifact rejection procedure. Higher demands on balance control were associated with a global increase in iAPF and a decrease in lower alpha power. These results may indicate increased thalamo-cortical information transfer and general cortical activation, respectively. In addition, a significant increase in upper alpha activity was observed in the fronto-central region whereas it decreased in the centro-parietal region. Furthermore, midline theta increased with higher task demands probably indicating activation of error detection/processing mechanisms. IAPF as well as theta and alpha power were correlated with platform movements. The results provide new insights into spectral and spatial characteristics of cortical oscillations subserving balance control. This information may be particularly useful in a clinical context as it could be used to reveal cortical contributions to balance dysfunction in specific populations such as Parkinson’s or vestibular loss. However, this should be addressed in future studies. PMID:26779005

Higher Balance Task Demands are Associated with an Increase in Individual Alpha Peak Frequency.

PubMed

Hülsdünker, Thorben; Mierau, Andreas; Strüder, Heiko K

2015-01-01

Balance control is fundamental for most daily motor activities, and its impairment is associated with an increased risk of falling. Growing evidence suggests the human cortex is essentially contributing to the control of standing balance. However, the exact mechanisms remain unclear and need further investigation. In a previous study, we introduced a new protocol to identify electrocortical activity associated with performance of different continuous balance tasks with the eyes opened. The aim of this study was to extend our previous results by investigating the individual alpha peak frequency (iAPF), a neurophysiological marker of thalamo-cortical information transmission, which remained unconsidered so far in balance research. Thirty-seven subjects completed nine balance tasks varying in surface stability and base of support. Electroencephalography (EEG) was recorded from 32 scalp locations throughout balancing with the eyes closed to ensure reliable identification of the iAPF. Balance performance was quantified as the sum of anterior-posterior and medio-lateral movements of the supporting platform. The iAPF, as well as power in the theta, lower alpha and upper alpha frequency bands were determined for each balance task after applying an ICA-based artifact rejection procedure. Higher demands on balance control were associated with a global increase in iAPF and a decrease in lower alpha power. These results may indicate increased thalamo-cortical information transfer and general cortical activation, respectively. In addition, a significant increase in upper alpha activity was observed in the fronto-central region whereas it decreased in the centro-parietal region. Furthermore, midline theta increased with higher task demands probably indicating activation of error detection/processing mechanisms. IAPF as well as theta and alpha power were correlated with platform movements. The results provide new insights into spectral and spatial characteristics of cortical oscillations subserving balance control. This information may be particularly useful in a clinical context as it could be used to reveal cortical contributions to balance dysfunction in specific populations such as Parkinson's or vestibular loss. However, this should be addressed in future studies.

Improved determination of dynamic balance using the centre of mass and centre of pressure inclination variables in a complete golf swing cycle.

PubMed

Choi, Ahnryul; Sim, Taeyong; Mun, Joung Hwan

2016-01-01

Golf requires proper dynamic balance to accurately control the club head through a harmonious coordination of each human segment and joint. In this study, we evaluated the ability for dynamic balance during a golf swing by using the centre of mass (COM)-centre of pressure (COP) inclination variables. Twelve professional, 13 amateur and 10 novice golfers participated in this study. Six infrared cameras, two force platforms and SB-Clinic software were used to measure the net COM and COP trajectories. In order to evaluate dynamic balance ability, the COM-COP inclination angle, COM-COP inclination angular velocity and normalised COM-COP inclination angular jerk were used. Professional golfer group revealed a smaller COM-COP inclination angle and angular velocity than novice golfer group in the lead/trail direction (P < 0.01). In the normalised COM-COP inclination angular jerk, the professional golfer group showed a lower value than the other two groups in all directions. Professional golfers tend to exhibit improved dynamic balance, and this can be attributed to the neuromusculoskeletal system that maintains balance with proper postural control. This study has the potential to allow for an evaluation of the dynamic balance mechanism and will provide useful basic information for swing training and prevention of golf injuries.

Specific interference between a cognitive task and sensory organization for stance balance control in healthy young adults: visuospatial effects.

PubMed

Chong, Raymond K Y; Mills, Bradley; Dailey, Leanna; Lane, Elizabeth; Smith, Sarah; Lee, Kyoung-Hyun

2010-07-01

We tested the hypothesis that a computational overload results when two activities, one motor and the other cognitive that draw on the same neural processing pathways, are performed concurrently. Healthy young adult subjects carried out two seemingly distinct tasks of maintaining standing balance control under conditions of low (eyes closed), normal (eyes open) or high (eyes open, sway-referenced surround) visuospatial processing load while concurrently performing a cognitive task of either subtracting backwards by seven or generating words of the same first letter. A decrease in the performance of the balance control task and a decrement in the speed and accuracy of responses were noted during the subtraction but not the word generation task. The interference in the subtraction task was isolated to the first trial of the high but not normal or low visuospatial conditions. Balance control improvements with repeated exposures were observed only in the low visuospatial conditions while performance in the other conditions remained compromised. These results suggest that sensory organization for balance control appear to draw on similar visuospatial computational resources needed for the subtraction but not the word generation task. In accordance with the theory of modularity in human performance, the contrast in results between the subtraction and word generation tasks suggests that the neural overload is related to competition for similar visuospatial processes rather than limited attentional resources. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Identification of the contribution of the ankle and hip joints to multi-segmental balance control

PubMed Central

2013-01-01

Background Human stance involves multiple segments, including the legs and trunk, and requires coordinated actions of both. A novel method was developed that reliably estimates the contribution of the left and right leg (i.e., the ankle and hip joints) to the balance control of individual subjects. Methods The method was evaluated using simulations of a double-inverted pendulum model and the applicability was demonstrated with an experiment with seven healthy and one Parkinsonian participant. Model simulations indicated that two perturbations are required to reliably estimate the dynamics of a double-inverted pendulum balance control system. In the experiment, two multisine perturbation signals were applied simultaneously. The balance control system dynamic behaviour of the participants was estimated by Frequency Response Functions (FRFs), which relate ankle and hip joint angles to joint torques, using a multivariate closed-loop system identification technique. Results In the model simulations, the FRFs were reliably estimated, also in the presence of realistic levels of noise. In the experiment, the participants responded consistently to the perturbations, indicated by low noise-to-signal ratios of the ankle angle (0.24), hip angle (0.28), ankle torque (0.07), and hip torque (0.33). The developed method could detect that the Parkinson patient controlled his balance asymmetrically, that is, the right ankle and hip joints produced more corrective torque. Conclusion The method allows for a reliable estimate of the multisegmental feedback mechanism that stabilizes stance, of individual participants and of separate legs. PMID:23433148

Target Water Consumption Calculation for Human Water Management based on Water Balance

NASA Astrophysics Data System (ADS)

Sang, X.; Zhai, Z.; Ye, Y.; Zhai, J.

2016-12-01

Degradation of the regional ecological environment has become increasingly serious due to the rapid increase of water usage. Critical to water consumption management is a good approach to control the growth of water usage. Through the identification and analysis of water consumption for various sectors in the hydrosocial cycle, the method for calculating the regional target water consumption also is derived based on water balance theory. Analysis shows that during 1980 - 2004 in Tianjin City, there were 22 years in which the actual water consumption of Tianjin exceeded its target water consumption, with an average excess of 66 million m3 annually. Moreover, calculations show that the maximum human target water consumption water supply is 1.91 billion m3/a. If water consumption is controlled according to the target, the sustainable development of water resource, economic and social growth, and ecological environment in this region can be expected to be achieved.

Intrinsic and Extrinsic Contributions to Seated Balance in the Sagittal and Coronal Planes: Implications for Trunk Control After Spinal Cord Injury.

PubMed

Audu, Musa L; Triolo, Ronald J

2015-08-01

The contributions of intrinsic (passive) and extrinsic (active) properties of the human trunk, in terms of the simultaneous actions about the hip and spinal joints, to the control of sagittal and coronal seated balance were examined. Able-bodied (ABD) and spinal-cord-injured (SCI) volunteers sat on a moving platform which underwent small amplitude perturbations in the anterior-posterior (AP) and medial-lateral (ML) directions while changes to trunk orientation were measured. A linear parametric model that related platform movement to trunk angle was fit to the experimental data by identifying model parameters in the time domain. The results showed that spinal cord injury leads to a systematic reduction in the extrinsic characteristics, while most of the intrinsic characteristics were rarely affected. In both SCI and ABD individuals, passive characteristics alone were not enough to maintain seated balance. Passive stiffness in the ML direction was almost 3 times that in the AP direction, making more extrinsic mechanisms necessary for balance in the latter direction. Proportional and derivative terms of the extrinsic model made the largest contribution to the overall output from the active system, implying that a simple proportional plus derivative (PD) controller structure will suffice for restoring seated balance after spinal cord injury.

Design and Validation of a Low-Cost Portable Device to Quantify Postural Stability.

PubMed

Zhu, Yong

2017-03-18

Measurement of the displacement of the center-of-pressure (COP) is an important tool used in biomechanics to assess postural stability and human balance. The goal of this research was to design and validate a low-cost portable device that can offer a quick indication of the state of postural stability and human balance related conditions. Approximate entropy (ApEn) values reflecting the amount of irregularity hiding in COP oscillations were used to calculate the index. The prototype adopted a portable design using the measurements of the load cells located at the four corners of a low-cost force platform. The test subject was asked to stand on the device in a quiet, normal, upright stance for 30 s with eyes open and subsequently for 30 s with eyes closed. Based on the COP displacement signals, the ApEn values were calculated. The results indicated that the prototype device was capable of capturing the increase in regularity of postural control in the visual-deprivation conditions. It was also able to decipher the subtle postural control differences along anterior-posterior and medial-lateral directions. The data analysis demonstrated that the prototype would enable the quantification of postural stability and thus provide a low-cost portable device to assess many conditions related to postural stability and human balance such as aging and pathologies.

Assessment of Visual Reliance in Balance Control: An Inexpensive Extension of the Static Posturography.

PubMed

Púčik, Jozef; Šaling, Marián; Lukáč, Tomáš; Ondráček, Oldřich; Kucharík, Martin

2014-01-01

Ability of humans to maintain balance in an upright stance and during movement activities is one of the most natural skills affecting everyday life. This ability progressively deteriorates with increasing age, and balance impairment, often aggravated by age-related diseases, can result in falls that adversely impact the quality of life. Falls represent serious problems of health concern associated with aging. Many investigators, involved in different science disciplines such as medicine, engineering, psychology, and sport, have been attracted by a research of the human upright stance. In a clinical practice, stabilometry based on the force plate is the most widely available procedure used to evaluate the balance. In this paper, we have proposed a low-cost extension of the conventional stabilometry by the multimedia technology that allows identifying potentially disturbing effects of visual sensory information. Due to the proposed extension, a stabilometric assessment in terms of line integral of center of pressure (COP) during moving scene stimuli shows higher discrimination power between young healthy and elderly subjects with supposed stronger visual reliance.

Assessment of Visual Reliance in Balance Control: An Inexpensive Extension of the Static Posturography

PubMed Central

Púčik, Jozef; Šaling, Marián; Lukáč, Tomáš; Ondráček, Oldřich; Kucharík, Martin

2014-01-01

Ability of humans to maintain balance in an upright stance and during movement activities is one of the most natural skills affecting everyday life. This ability progressively deteriorates with increasing age, and balance impairment, often aggravated by age-related diseases, can result in falls that adversely impact the quality of life. Falls represent serious problems of health concern associated with aging. Many investigators, involved in different science disciplines such as medicine, engineering, psychology, and sport, have been attracted by a research of the human upright stance. In a clinical practice, stabilometry based on the force plate is the most widely available procedure used to evaluate the balance. In this paper, we have proposed a low-cost extension of the conventional stabilometry by the multimedia technology that allows identifying potentially disturbing effects of visual sensory information. Due to the proposed extension, a stabilometric assessment in terms of line integral of center of pressure (COP) during moving scene stimuli shows higher discrimination power between young healthy and elderly subjects with supposed stronger visual reliance. PMID:27006930

A dynamic human water and electrolyte balance model for verification and optimization of life support systems in space flight applications

NASA Astrophysics Data System (ADS)

Hager, P.; Czupalla, M.; Walter, U.

2010-11-01

In this paper we report on the development of a dynamic MATLAB SIMULINK® model for the water and electrolyte balance inside the human body. This model is part of an environmentally sensitive dynamic human model for the optimization and verification of environmental control and life support systems (ECLSS) in space flight applications. An ECLSS provides all vital supplies for supporting human life on board a spacecraft. As human space flight today focuses on medium- to long-term missions, the strategy in ECLSS is shifting to closed loop systems. For these systems the dynamic stability and function over long duration are essential. However, the only evaluation and rating methods for ECLSS up to now are either expensive trial and error breadboarding strategies or static and semi-dynamic simulations. In order to overcome this mismatch the Exploration Group at Technische Universität München (TUM) is developing a dynamic environmental simulation, the "Virtual Habitat" (V-HAB). The central element of this simulation is the dynamic and environmentally sensitive human model. The water subsystem simulation of the human model discussed in this paper is of vital importance for the efficiency of possible ECLSS optimizations, as an over- or under-scaled water subsystem would have an adverse effect on the overall mass budget. On the other hand water has a pivotal role in the human organism. Water accounts for about 60% of the total body mass and is educt and product of numerous metabolic reactions. It is a transport medium for solutes and, due to its high evaporation enthalpy, provides the most potent medium for heat load dissipation. In a system engineering approach the human water balance was worked out by simulating the human body's subsystems and their interactions. The body fluids were assumed to reside in three compartments: blood plasma, interstitial fluid and intracellular fluid. In addition, the active and passive transport of water and solutes between those compartments was modeled dynamically. A kidney model regulates the electrolyte concentration in body fluids (osmolality) in narrow confines and a thirst mechanism models the urge to ingest water. A controlled exchange of water and electrolytes with other human subsystems, as well as with the environment, is implemented. Finally, the changes in body composition due to muscle growth are accounted for. The outcome of this is a dynamic water and electrolyte balance, which is capable of representing body reactions like thirst and headaches, as well as heat stroke and collapse, as a response to its work load and environment.

SVR versus neural-fuzzy network controllers for the sagittal balance of a biped robot.

PubMed

Ferreira, João P; Crisóstomo, Manuel M; Coimbra, A Paulo

2009-12-01

The real-time balance control of an eight-link biped robot using a zero moment point (ZMP) dynamic model is difficult due to the processing time of the corresponding equations. To overcome this limitation, two alternative intelligent computing control techniques were compared: one based on support vector regression (SVR) and another based on a first-order Takagi-Sugeno-Kang (TSK)-type neural-fuzzy (NF) network. Both methods use the ZMP error and its variation as inputs and the output is the correction of the robot's torso necessary for its sagittal balance. The SVR and the NF were trained based on simulation data and their performance was verified with a real biped robot. Two performance indexes are proposed to evaluate and compare the online performance of the two control methods. The ZMP is calculated by reading four force sensors placed under each robot's foot. The gait implemented in this biped is similar to a human gait that was acquired and adapted to the robot's size. Some experiments are presented and the results show that the implemented gait combined either with the SVR controller or with the TSK NF network controller can be used to control this biped robot. The SVR and the NF controllers exhibit similar stability, but the SVR controller runs about 50 times faster.

Behavioral and neuroimaging evidence for overreliance on habit learning in alcohol-dependent patients

PubMed Central

Sjoerds, Z; de Wit, S; van den Brink, W; Robbins, T W; Beekman, A T F; Penninx, B W J H; Veltman, D J

2013-01-01

Substance dependence is characterized by compulsive drug-taking despite negative consequences. Animal research suggests an underlying imbalance between goal-directed and habitual action control with chronic drug use. However, this imbalance, and its associated neurophysiological mechanisms, has not yet been experimentally investigated in human drug abusers. The aim of the present study therefore was to assess the balance between goal-directed and habit-based learning and its neural correlates in abstinent alcohol-dependent (AD) patients. A total of 31 AD patients and 19 age, gender and education matched healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) during completion of an instrumental learning task designed to study the balance between goal-directed and habit learning. Task performance and task-related blood oxygen level-dependent activations in the brain were compared between AD patients and healthy matched controls. Findings were additionally associated with duration and severity of alcohol dependence. The results of this study provide evidence for an overreliance on stimulus-response habit learning in AD compared with HC, which was accompanied by decreased engagement of brain areas implicated in goal-directed action (ventromedial prefrontal cortex and anterior putamen) and increased recruitment of brain areas implicated in habit learning (posterior putamen) in AD patients. In conclusion, this is the first human study to provide experimental evidence for a disturbed balance between goal-directed and habitual control by use of an instrumental learning task, and to directly implicate cortical dysfunction to overreliance on inflexible habits in AD patients. PMID:24346135

Behavioral and neuroimaging evidence for overreliance on habit learning in alcohol-dependent patients.

PubMed

Sjoerds, Z; de Wit, S; van den Brink, W; Robbins, T W; Beekman, A T F; Penninx, B W J H; Veltman, D J

2013-12-17

Substance dependence is characterized by compulsive drug-taking despite negative consequences. Animal research suggests an underlying imbalance between goal-directed and habitual action control with chronic drug use. However, this imbalance, and its associated neurophysiological mechanisms, has not yet been experimentally investigated in human drug abusers. The aim of the present study therefore was to assess the balance between goal-directed and habit-based learning and its neural correlates in abstinent alcohol-dependent (AD) patients. A total of 31 AD patients and 19 age, gender and education matched healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) during completion of an instrumental learning task designed to study the balance between goal-directed and habit learning. Task performance and task-related blood oxygen level-dependent activations in the brain were compared between AD patients and healthy matched controls. Findings were additionally associated with duration and severity of alcohol dependence. The results of this study provide evidence for an overreliance on stimulus-response habit learning in AD compared with HC, which was accompanied by decreased engagement of brain areas implicated in goal-directed action (ventromedial prefrontal cortex and anterior putamen) and increased recruitment of brain areas implicated in habit learning (posterior putamen) in AD patients. In conclusion, this is the first human study to provide experimental evidence for a disturbed balance between goal-directed and habitual control by use of an instrumental learning task, and to directly implicate cortical dysfunction to overreliance on inflexible habits in AD patients.

The Effect of Part-simulation of Weightlessness on Human Control of Bilateral Teleoperation: Neuromotor Considerations

NASA Technical Reports Server (NTRS)

Corker, K.; Bejczy, A. K.

1984-01-01

The effect of weightlessness on the human operator's performance in force reflecting position control of remote manipulators was investigated. A gravity compensation system was developed to simulate the effect of weightlessness on the operator's arm. A universal force reflecting hand controller (FRHC) and task simulation software were employed. Two experiments were performed because of anticipated disturbances in neuromotor control specification on the human operator in an orbital control environment to investigate: (1) the effect of controller stiffness on the attainment of a learned terminal position in the three dimensional controller space, and (2) the effect of controller stiffness and damping on force tracking of the contour of a simulated three dimensional cube using the part simulation of weightless conditions. The results support the extension of neuromotor control models, which postulate a stiffness balance encoding of terminal position, to three dimensional motion of a multilink system, confirm the existence of a disturbance in human manual control performance under gravity compensated conditions, and suggest techniques for compensation of weightlessness induced performance decrement through appropriate specification of hand controller response characteristics. These techniques are based on the human control model.

A link-segment model of upright human posture for analysis of head-trunk coordination

NASA Technical Reports Server (NTRS)

Nicholas, S. C.; Doxey-Gasway, D. D.; Paloski, W. H.

1998-01-01

Sensory-motor control of upright human posture may be organized in a top-down fashion such that certain head-trunk coordination strategies are employed to optimize visual and/or vestibular sensory inputs. Previous quantitative models of the biomechanics of human posture control have examined the simple case of ankle sway strategy, in which an inverted pendulum model is used, and the somewhat more complicated case of hip sway strategy, in which multisegment, articulated models are used. While these models can be used to quantify the gross dynamics of posture control, they are not sufficiently detailed to analyze head-trunk coordination strategies that may be crucial to understanding its underlying mechanisms. In this paper, we present a biomechanical model of upright human posture that extends an existing four mass, sagittal plane, link-segment model to a five mass model including an independent head link. The new model was developed to analyze segmental body movements during dynamic posturography experiments in order to study head-trunk coordination strategies and their influence on sensory inputs to balance control. It was designed specifically to analyze data collected on the EquiTest (NeuroCom International, Clackamas, OR) computerized dynamic posturography system, where the task of maintaining postural equilibrium may be challenged under conditions in which the visual surround, support surface, or both are in motion. The performance of the model was tested by comparing its estimated ground reaction forces to those measured directly by support surface force transducers. We conclude that this model will be a valuable analytical tool in the search for mechanisms of balance control.

Analysis of muscle activation in lower extremity for static balance.

PubMed

Chakravarty, Kingshuk; Chatterjee, Debatri; Das, Rajat Kumar; Tripathy, Soumya Ranjan; Sinha, Aniruddha

2017-07-01

Balance plays an important role for human bipedal locomotion. Degeneration of balance control is prominent in stroke patients, elderly adults and even for majority of obese people. Design of personalized balance training program, in order to strengthen muscles, requires the analysis of muscle activation during an activity. In this paper we have proposed an affordable and portable approach to analyze the relationship between the static balance strategy and activation of various lower extremity muscles. To do that we have considered Microsoft Kinect XBox 360 as a motion sensing device and Wii balance board for measuring external force information. For analyzing the muscle activation pattern related to static balance, participants are asked to do the single limb stance (SLS) exercise on the balance board and in front of the Kinect. Static optimization to minimize the overall muscle activation pattern is carried out using OpenSim, which is an open-source musculoskeletal simulation software. The study is done on ten normal and ten obese people, grouped according to body mass index (BMI). Results suggest that the lower extremity muscles like biceps femoris, psoas major, sartorius, iliacus play the major role for both maintaining the balance using one limb as well as maintaining the flexion of the other limb during SLS. Further investigations reveal that the higher muscle activations of the flexed leg for normal group demonstrate higher strength. Moreover, the lower muscle activation of the standing leg for normal group demonstrate more headroom for the biceps femoris-short-head and psoas major to withstand the load and hence have better static balance control.

An Engineering Model of Human Balance Control-Part I: Biomechanical Model.

PubMed

Barton, Joseph E; Roy, Anindo; Sorkin, John D; Rogers, Mark W; Macko, Richard

2016-01-01

We developed a balance measurement tool (the balanced reach test (BRT)) to assess standing balance while reaching and pointing to a target moving in three-dimensional space according to a sum-of-sines function. We also developed a three-dimensional, 13-segment biomechanical model to analyze performance in this task. Using kinematic and ground reaction force (GRF) data from the BRT, we performed an inverse dynamics analysis to compute the forces and torques applied at each of the joints during the course of a 90 s test. We also performed spectral analyses of each joint's force activations. We found that the joints act in a different but highly coordinated manner to accomplish the tracking task-with individual joints responding congruently to different portions of the target disk's frequency spectrum. The test and the model also identified clear differences between a young healthy subject (YHS), an older high fall risk (HFR) subject before participating in a balance training intervention; and in the older subject's performance after training (which improved to the point that his performance approached that of the young subject). This is the first phase of an effort to model the balance control system with sufficient physiological detail and complexity to accurately simulate the multisegmental control of balance during functional reach across the spectra of aging, medical, and neurological conditions that affect performance. Such a model would provide insight into the function and interaction of the biomechanical and neurophysiological elements making up this system; and system adaptations to changes in these elements' performance and capabilities.

Postural threat differentially affects the feedforward and feedback components of the vestibular-evoked balance response.

PubMed

Osler, Callum J; Tersteeg, M C A; Reynolds, Raymond F; Loram, Ian D

2013-10-01

Circumstances may render the consequence of falling quite severe, thus maximising the motivation to control postural sway. This commonly occurs when exposed to height and may result from the interaction of many factors, including fear, arousal, sensory information and perception. Here, we examined human vestibular-evoked balance responses during exposure to a highly threatening postural context. Nine subjects stood with eyes closed on a narrow walkway elevated 3.85 m above ground level. This evoked an altered psycho-physiological state, demonstrated by a twofold increase in skin conductance. Balance responses were then evoked by galvanic vestibular stimulation. The sway response, which comprised a whole-body lean in the direction of the edge of the walkway, was significantly and substantially attenuated after ~800 ms. This demonstrates that a strong reason to modify the balance control strategy was created and subjects were highly motivated to minimise sway. Despite this, the initial response remained unchanged. This suggests little effect on the feedforward settings of the nervous system responsible for coupling pure vestibular input to functional motor output. The much stronger, later effect can be attributed to an integration of balance-relevant sensory feedback once the body was in motion. These results demonstrate that the feedforward and feedback components of a vestibular-evoked balance response are differently affected by postural threat. Although a fear of falling has previously been linked with instability and even falling itself, our findings suggest that this relationship is not attributable to changes in the feedforward vestibular control of balance. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

ENVIRONMENTAL ACCOUNTING: BALANCING ECONOMIC GROWTH AND ENVIRONMENTAL QUALITY

EPA Science Inventory

Modern industrial economies depend on the environment to support economic production and a high standard of living. Economic production, in turn, impacts the productivity of ecosystems through waste production and resource use or diversion. Human activities control many energy an...

Stick balancing, falls and Dragon-Kings

NASA Astrophysics Data System (ADS)

Cabrera, J. L.; Milton, J. G.

2012-05-01

The extent to which the occurrence of falls, the dominant feature of human attempts to balance a stick at their fingertip, can be predicted is examined in the context of the "Dragon-King" hypothesis. For skilled stick balancers, fluctuations in the controlled variable, namely the vertical displacement angle θ, exhibit power law behaviors. When stick balancing is made less stable by either decreasing the length of the stick or by requiring the subject to balance the stick on the surface of a table tennis racket, systematic departures from the power law behaviors are observed in the range of large θ. This observation raises the possibility that the presence of departures from the power law in the large length scale region, possibly Dragon-Kings, may identify situations in which the occurrence of a fall is more imminent. However, whether or not Dragon-Kings are observed, there is a Weibull-type survival function for stick falling. The possibility that increased risk of falling can, at least to some extent, be predicted from fluctuations in the controlled variable before the event occurs has important implications for the development of preventative strategies for the management of phenomena ranging from earthquakes to epileptic seizures to falls in the elderly.

Diurnal changes in postural control in normal children: Computerized static and dynamic assessments.

PubMed

Bourelle, Sophie; Taiar, Redha; Berge, Benoit; Gautheron, Vincent; Cottalorda, Jerome

2014-01-01

Mild traumatic brain injury (mTBI) causes postural control deficits and accordingly comparison of aberrant postural control against normal postural control may help diagnose mTBI. However, in the current literature, little is known regarding the normal pattern of postural control in young children. This study was therefore conducted as an effort to fill this knowledge gap. Eight normal school-aged children participated. Posture assessment was conducted before (7-8 a.m. in the morning) and after (4-7 p.m. in the afternoon) school on regular school days using the Balance Master® evaluation system composed of 3 static tests and 2 dynamic balance tests. A significant difference in the weight-bearing squats was detected between morning hours and afternoon hours (P < 0.05). By end of afternoon, the body weight was borne mainly on the left side with the knee fully extended and at various degrees of knee flexion. A significantly better directional control of the lateral rhythmic weight shifts was observed at the end of the afternoon than at morning hours (P < 0.05). In summary, most of our findings are inconsistent with results from previous studies in adults, suggesting age-related differences in posture control in humans. On a regular school day, the capacity of postural control and laterality or medio-lateral balance in children varies between morning and afternoon hours. We suggest that posturographic assessment in children, either in normal (e.g., physical education and sports training) or in abnormal conditions (e.g., mTBI-associated balance disorders), be better performed late in the afternoon.

Learning and tuning fuzzy logic controllers through reinforcements

NASA Technical Reports Server (NTRS)

Berenji, Hamid R.; Khedkar, Pratap

1992-01-01

A new method for learning and tuning a fuzzy logic controller based on reinforcements from a dynamic system is presented. In particular, our Generalized Approximate Reasoning-based Intelligent Control (GARIC) architecture: (1) learns and tunes a fuzzy logic controller even when only weak reinforcements, such as a binary failure signal, is available; (2) introduces a new conjunction operator in computing the rule strengths of fuzzy control rules; (3) introduces a new localized mean of maximum (LMOM) method in combining the conclusions of several firing control rules; and (4) learns to produce real-valued control actions. Learning is achieved by integrating fuzzy inference into a feedforward network, which can then adaptively improve performance by using gradient descent methods. We extend the AHC algorithm of Barto, Sutton, and Anderson to include the prior control knowledge of human operators. The GARIC architecture is applied to a cart-pole balancing system and has demonstrated significant improvements in terms of the speed of learning and robustness to changes in the dynamic system's parameters over previous schemes for cart-pole balancing.

[Anti-doping control and public health: limits to the exposure of human health to risk in the name of sporting glory].

PubMed

Aith, Fernando Mussa Abujamra

2013-10-01

Given the current regulatory environment surrounding doping in the world, and in view of the recurring scandals linking leading athletes in a variety of sports with doping, this paper aims to provide some thoughts on the relationship between doping and public health, taking as base reference the risks doping poses to health and considering the regulatory options that have been adopted by the international community and the sports federations to control and supervise this unsporting and risky practice. The text seeks to reflect on the necessary balance between sport and health, as well as on the role of the state in preserving this balance.

Suppression of human anti-inflammatory plasma cytokines IL-10 and IL-1RA with elevation of proinflammatory cytokine IFN-gamma during the isolation of the Antarctic winter

NASA Technical Reports Server (NTRS)

Shearer, William T.; Lee, Bang-Ning; Cron, Stanley G.; Rosenblatt, Howard M.; Smith, E. O'Brian; Lugg, Desmond J.; Nickolls, Peter M.; Sharp, Robert M.; Rollings, Karl; Reuben, James M.

2002-01-01

Cellular immune function has been shown to be decreased and latent virus shedding to be increased in human beings isolated during the Antarctic winter, a model used for assessing some effects of space flight. However, the balance of proinflammatory (IFN-gamma) and anti-inflammatory (IL-10 and IL-1RA) cytokines has not previously been evaluated. We therefore sought to determine whether isolation during the Antarctic winter would alter the proinflammatory and anti-inflammatory cytokine balance. Cytokine levels were measured with ELISA in monthly plasma samples from January through September 1999 in 21 study subjects in the Antarctic and 7 control subjects on Macquarie Island. There was a significant time-dependent increase in plasma IFN-gamma (P =.039) as well as decreases in IL-10 (P =.042) and IL-1RA (P =.053) in the study subjects compared with the control subjects. The study subjects also had significantly increased plasma IFN-gamma levels (P < or =.045) but decreased IL-10 and IL-1RA levels (P < or =.036) at individual time points of isolation. Isolation of human beings in the Antarctic appears to shift the plasma cytokine balance toward a proinflammatory profile. These observations are consistent with T-cell activation that might be due to activation of latent viruses, and they could hold importance for determining the risks of space flight.

Affordable, automatic quantitative fall risk assessment based on clinical balance scales and Kinect data.

PubMed

Colagiorgio, P; Romano, F; Sardi, F; Moraschini, M; Sozzi, A; Bejor, M; Ricevuti, G; Buizza, A; Ramat, S

2014-01-01

The problem of a correct fall risk assessment is becoming more and more critical with the ageing of the population. In spite of the available approaches allowing a quantitative analysis of the human movement control system's performance, the clinical assessment and diagnostic approach to fall risk assessment still relies mostly on non-quantitative exams, such as clinical scales. This work documents our current effort to develop a novel method to assess balance control abilities through a system implementing an automatic evaluation of exercises drawn from balance assessment scales. Our aim is to overcome the classical limits characterizing these scales i.e. limited granularity and inter-/intra-examiner reliability, to obtain objective scores and more detailed information allowing to predict fall risk. We used Microsoft Kinect to record subjects' movements while performing challenging exercises drawn from clinical balance scales. We then computed a set of parameters quantifying the execution of the exercises and fed them to a supervised classifier to perform a classification based on the clinical score. We obtained a good accuracy (~82%) and especially a high sensitivity (~83%).

[Nutrition, acid-base metabolism, cation-anion difference and total base balance in humans].

PubMed

Mioni, R; Sala, P; Mioni, G

2008-01-01

The relationship between dietary intake and acid-base metabolism has been investigated in the past by means of the inorganic cation-anion difference (C(+)(nm)-A(-)(nm)) method based on dietary ash-acidity titration after the oxidative combustion of food samples. Besides the inorganic components of TA (A(-)(nm)-C(+)(nm)), which are under renal control, there are also metabolizable components (A(-)(nm)-C(+)(nm)) of TA, which are under the control of the intermediate metabolism. The whole body base balance, NBb(W), is obtained only by the application of C(+)(nm)-A(-)(nm) to food, feces and urine, while the metabolizable component (A(-)(nm)-C(+)(nm)) is disregarded. A novel method has been subsequently suggested to calculate the net balance of fixed acid, made up by the difference between the input of net endogenous acid production: NEAP = SO(4)(2-)+A(-)(m)-(C(+)(nm)-A(-)(nm)), and the output of net acid excretion: NAE = TA + NH(4)(+) - HCO(3)(-). This approach has been criticized because 1) it includes metabolizable acids, whose production cannot be measured independently; 2) the specific control of metabolizable acid and base has been incorrectly attributed to the kidney; 3) the inclusion of A-m in the balance input generates an acid overload; 4) the object of measurement in making up a balance has to be the same, a condition not fulfilled as NEAP is different from NAE. Lastly, by rearranging the net balance of the acid equation, the balance of nonmetabolizable acid equation is obtained. Therefore, any discrepancy between these two equations is due to the inaccuracy in the urine measurement of metabolizable cations and/or anions.

Metallothionein: a Potential Link in the Regulation of Zinc in Nutritional Immunity.

PubMed

Rahman, Mohammad Tariqur; Karim, Muhammad Manjurul

2018-03-01

Nutritional immunity describes mechanisms for withholding essential transition metals as well as directing the toxicity of these metals against infectious agents. Zinc is one of these transition elements that are essential for both humans and microbial pathogens. At the same time, Zn can be toxic both for man and microbes if its concentration is higher than the tolerance limit. Therefore a "delicate" balance of Zn must be maintained to keep the immune cells surveilling while making the level of Zn either to starve or to intoxicate the pathogens. On the other hand, the invading pathogens will exploit the host Zn pool for its survival and replication. Apparently, different sets of protein in human and bacteria are involved to maintain their Zn need. Metallothionein (MT)-a group of low molecular weight proteins, is well known for its Zn-binding ability and is expected to play an important role in that Zn balance at the time of active infection. However, the differences in structural, functional, and molecular control of biosynthesis between human and bacterial MT might play an important role to determine the proper use of Zn and the winning side. The current review explains the possible involvement of human and bacterial MT at the time of infection to control and exploit Zn for their need.

Incorporating Ecosystem Processes Controlling Carbon Balance Into Models of Coupled Human-Natural Systems

NASA Astrophysics Data System (ADS)

Currie, W.; Brown, D. G.; Brunner, A.; Fouladbash, L.; Hadzick, Z.; Hutchins, M.; Kiger, S. E.; Makino, Y.; Nassauer, J. I.; Robinson, D. T.; Riolo, R. L.; Sun, S.

2012-12-01

A key element in the study of coupled human-natural systems is the interactions of human populations with vegetation and soils. In human-dominated landscapes, vegetation production and change results from a combination of ecological processes and human decision-making and behavior. Vegetation is often dramatically altered, whether to produce food for humans and livestock, to harvest fiber for construction and other materials, to harvest fuel wood or feedstock for biofuels, or simply for cultural preferences as in the case of residential lawns with sparse trees in the exurban landscape. This alteration of vegetation and its management has a substantial impact on the landscape carbon balance. Models can be used to simulate scenarios in human-natural systems and to examine the integration of processes that determine future trajectories of carbon balance. However, most models of human-natural systems include little integration of the human alteration of vegetation with the ecosystem processes that regulate carbon balance. Here we illustrate a few case studies of pilot-study models that strive for this integration from our research across various types of landscapes. We focus greater detail on a fully developed research model linked to a field study of vegetation and soils in the exurban residential landscape of Southeastern Michigan, USA. The field study characterized vegetation and soil carbon storage in 5 types of ecological zones. Field-observed carbon storage in the vegetation in these zones ranged widely, from 150 g C/m2 in turfgrass zones, to 6,000 g C/m2 in zones defined as turfgrass with sparse woody vegetation, to 16,000 g C/m2 in a zone defined as dense trees and shrubs. Use of these zones facilitated the scaling of carbon pools to the landscape, where the areal mixtures of zone types had a significant impact on landscape C storage. Use of these zones also facilitated the use of the ecosystem process model Biome-BGC to simulate C trajectories and also facilitated our linkage of vegetation management, such as lawn mowing, fertilizer use, and leaf litter removal, to agent-based modeling of human preferences and behaviors.

Department of Defense Civilian Human Resources Strategic Plan

DTIC Science & Technology

2005-04-01

the strategic plan. A balanced scorecard approach was used to build the strategic plan. The balanced scorecard is a strategic management tool that...in the balanced scorecard format. Details of how the balanced scorecard addresses the DoD Human Capital Initiative are outlined in the Office of...mission- ready civilian workforce 8 GOALS AND OBJECTIVES The balanced scorecard approach reflects the changes the Department is undergoing and

Human balance, the evolution of bipedalism and dysequilibrium syndrome.

PubMed

Skoyles, John R

2006-01-01

A new model of the uniqueness, nature and evolution of human bipedality is presented in the context of the etiology of the balance disorder of dysequilibrium syndrome. Human bipedality is biologically novel in several remarkable respects. Humans are (a) obligate, habitual and diverse in their bipedalism, (b) hold their body carriage spinally erect in a multisegmental "antigravity pole", (c) use their forelimbs exclusively for nonlocomotion, (d) support their body weight exclusively by vertical balance and normally never use prehensile holds. Further, human bipedalism is combined with (e) upper body actions that quickly shift the body's center of mass (e.g. tennis serves, piggy-back carrying of children), (f) use transient unstable erect positions (dance, kicking and fighting), (g) body height that makes falls injurious, (h) stiff gait walking, and (i) endurance running. Underlying these novelties, I conjecture, is a species specific human vertical balance faculty. This faculty synchronizes any action with a skeletomuscular adjustment that corrects its potential destabilizing impact upon the projection of the body's center of mass over its foot support. The balance faculty depends upon internal models of the erect vertical body's geometrical relationship (and its deviations) to its support base. Due to the situation that humans are obligate erect terrestrial animals, two frameworks - the body- and gravity-defined frameworks - are in constant alignment in the vertical z-axis. This alignment allows human balance to adapt egocentric body cognitions to detect body deviations from the gravitational vertical. This link between human balance and the processing of geometrical orientation, I propose, accounts for the close link between balance and spatial cognition found in the cerebral cortex. I argue that cortical areas processing the spatial and other cognitions needed to enable vertical balance was an important reason for brain size expansion of Homo erectus. A novel source of evidence for this conjecture is the rare autosomal recessive condition of dysequilibrium syndrome. In dysequilibrium syndrome, individuals fail to learn to walk bipedally (with this not being due to sensory, vestibular nor motor coordination defects). Dysequilibrium syndrome is associated with severe spatial deficits that I conjecture underlie its balance dysfunction. The associated brain defects and gene mutations of dysequilibrium syndrome provide new opportunities to investigate (i) the neurological processes responsible for the human specific balance faculty, and (ii) through gene dating techniques, its evolution.

Environmental control and life support system selection for the first Lunar outpost habitat

NASA Technical Reports Server (NTRS)

Adams, Alan

1993-01-01

The planning for and feasibility study of an early human return mission to the lunar surface has been undertaken. The First Lunar Outpost (FLO) Mission philosophy is to use existing or near-term technology to achieve a human landing on the lunar surface in the year 2000. To support the crew the lunar habitat for the FLO mission incorporates an environmental control/life support system (ECLSS) design which meets the mission requirements and balances fixed mass and consumable mass. This tradeoff becomes one of regenerable life support systems versus open-loop systems.

Optimization of water balance within the martian crew life support system

NASA Astrophysics Data System (ADS)

Sychev, V.; Levinskikh, M.

The present-day scenarios of the first exploration mission differ in the total length crew size period of the stay on Mars etc However no matter the scenario one of the common problems is optimization of water balance within the crew life support system Water balance optimization implies in addition to regeneration of atmospheric moisture and urine also dehydration of biowastes In this mission all wastes will be stored and for this reason safe storage is prerequisite Investigations of two-component laboratory BLSS in which the autotrophic component was composed of algae Spirulina platensis and the heterotrophic component was represented by Japanese quail Coturnix coturnix japonica dom showed that optimization of the autotrophic and heterotrophic gas exchange and water regeneration from quail biowastes could raise the system susbstance balance to 76 of the total balance during autonomic cultivation of algae and birds In these investigations dehydration of quail biowastes caused significant pollution of water and air by organics toxic for humans It was demonstrated that the sorption technologies applied on the Russian space station MIR and ISS cannot fully absorb organic contaminants released in the process of quail wastes drying Algal suspension as a hydrobiological filter was able to control the organic pollination of both air and water These results are in agreement with the data of ground-based simulation studies with participation of human subjects at IBMP According to the simulation data intensive

A new paradigm for human stick balancing: a suspended not an inverted pendulum.

PubMed

Lee, Kwee-Yum; O'Dwyer, Nicholas; Halaki, Mark; Smith, Richard

2012-09-01

We studied 14 skilled subjects balancing a stick (a television antenna, 52 cm, 34 g) on their middle fingertip. Comprehensive three-dimensional analyses revealed that the movement of the finger was 1.75 times that of the stick tip, such that the balanced stick behaved more like a normal noninverted pendulum than the inverted pendulum common to engineering models for stick balancing using motors. The average relation between the torque applied to the stick and its angle of deviation from the vertical was highly linear, consistent with simple harmonic motion. We observed clearly greater rotational movement of the stick in the anteroposterior plane than the mediolateral plane. Despite this magnitude difference, the duration of stick oscillatory cycles was very similar in both planes, again consistent with simple harmonic motion. The control parameter in balancing was the ratio of active torque applied to the stick relative to gravitational torque. It determined both the pivot point and oscillatory cycle period of the pendulum. The pivot point was located at the radius of gyration (about the centre of mass) of the stick from its centre of mass, showing that the subjects attuned to the gravitational dynamics and mass distribution of the stick. Hence, the key to controlling instability here was mastery of the physics of the unstable object. The radius of gyration may--similar to centre of mass--contribute to the kinesthesis of rotating limb segments and control of their gravitational dynamics.

Natural Immunity to HIV: a delicate balance between strength and control.

PubMed

Poudrier, Johanne; Thibodeau, Valérie; Roger, Michel

2012-01-01

Understanding how the mucosal immune system in the human female reproductive tract might prevent or facilitate HIV infection has important implications for the design of effective interventions. We and others have established cohorts of highly-exposed, HIV-seronegative individuals, such as HIV-uninfected commercial sex workers, who have remained HIV-negative after more than 5 years of active prostitution. Observations obtained in studies of such individuals, who represent a model of natural immunity to HIV, indicate that HIV resistance may be associated with the host's capacity to preserve systemic integrity by constraining immune activity and controlling inflammatory conditions at the mucosal point of entry. This likely necessitates the orchestration of balanced, first-line and adaptive immune responses.

Development of the ECLSS Sizing Analysis Tool and ARS Mass Balance Model Using Microsoft Excel

NASA Technical Reports Server (NTRS)

McGlothlin, E. P.; Yeh, H. Y.; Lin, C. H.

1999-01-01

The development of a Microsoft Excel-compatible Environmental Control and Life Support System (ECLSS) sizing analysis "tool" for conceptual design of Mars human exploration missions makes it possible for a user to choose a certain technology in the corresponding subsystem. This tool estimates the mass, volume, and power requirements of every technology in a subsystem and the system as a whole. Furthermore, to verify that a design sized by the ECLSS Sizing Tool meets the mission requirements and integrates properly, mass balance models that solve for component throughputs of such ECLSS systems as the Water Recovery System (WRS) and Air Revitalization System (ARS) must be developed. The ARS Mass Balance Model will be discussed in this paper.

Dietary blueberry improves cognition among older adults in a randomized, double-blind, placebo-controlled trial

USDA-ARS?s Scientific Manuscript database

As populations shift to include a larger proportion of older adults, the necessity of research targeting older populations is becoming increasingly apparent. Changes in motor coordination during ‘normal’ aging, in animals and humans, include decrements in balance and locomotion. Parallel to alterati...

Chemotherapy Necessitates Increased Immune Control of HHVs: A Cause of Persistent Inflammation Enabling Protracted Fatigue in Breast Cancer Survivors

DTIC Science & Technology

2013-10-01

survivors. 15. SUBJECT TERMS breast cancer, chemotherapy, immunology, human herpes viruses, survivor fatigue 16. SECURITY CLASSIFICATION OF...hypothesizes that chemotherapy can permanently alter the balance between the immune system and chronic herpes virus infections and the resultant

Daily supplementation with mushroom (Agaricus bisporus) improves balance and working memory in aged rats

USDA-ARS?s Scientific Manuscript database

Animals and humans show decrements in motor control, cognition, and brain function during normal aging, partly due to the long-term effects of oxidative stress and inflammation. Recent studies have identified a number of fruits and vegetables, whose phytochemical make-up contains potent antioxidant ...

eEF2K/eEF2 Pathway Controls the Excitation/Inhibition Balance and Susceptibility to Epileptic Seizures

PubMed Central

Heise, Christopher; Taha, Elham; Murru, Luca; Ponzoni, Luisa; Cattaneo, Angela; Guarnieri, Fabrizia C.; Montani, Caterina; Mossa, Adele; Vezzoli, Elena; Ippolito, Giulio; Zapata, Jonathan; Barrera, Iliana; Ryazanov, Alexey G.; Cook, James; Poe, Michael; Stephen, Michael Rajesh; Kopanitsa, Maksym; Benfante, Roberta; Rusconi, Francesco; Braida, Daniela; Francolini, Maura; Proud, Christopher G.; Valtorta, Flavia; Passafaro, Maria; Sala, Mariaelvina; Bachi, Angela; Verpelli, Chiara; Rosenblum, Kobi; Sala, Carlo

2017-01-01

Abstract Alterations in the balance of inhibitory and excitatory synaptic transmission have been implicated in the pathogenesis of neurological disorders such as epilepsy. Eukaryotic elongation factor 2 kinase (eEF2K) is a highly regulated, ubiquitous kinase involved in the control of protein translation. Here, we show that eEF2K activity negatively regulates GABAergic synaptic transmission. Indeed, loss of eEF2K increases GABAergic synaptic transmission by upregulating the presynaptic protein Synapsin 2b and α5-containing GABAA receptors and thus interferes with the excitation/inhibition balance. This cellular phenotype is accompanied by an increased resistance to epilepsy and an impairment of only a specific hippocampal-dependent fear conditioning. From a clinical perspective, our results identify eEF2K as a potential novel target for antiepileptic drugs, since pharmacological and genetic inhibition of eEF2K can revert the epileptic phenotype in a mouse model of human epilepsy. PMID:27005990

Learning and tuning fuzzy logic controllers through reinforcements

NASA Technical Reports Server (NTRS)

Berenji, Hamid R.; Khedkar, Pratap

1992-01-01

This paper presents a new method for learning and tuning a fuzzy logic controller based on reinforcements from a dynamic system. In particular, our generalized approximate reasoning-based intelligent control (GARIC) architecture (1) learns and tunes a fuzzy logic controller even when only weak reinforcement, such as a binary failure signal, is available; (2) introduces a new conjunction operator in computing the rule strengths of fuzzy control rules; (3) introduces a new localized mean of maximum (LMOM) method in combining the conclusions of several firing control rules; and (4) learns to produce real-valued control actions. Learning is achieved by integrating fuzzy inference into a feedforward neural network, which can then adaptively improve performance by using gradient descent methods. We extend the AHC algorithm of Barto et al. (1983) to include the prior control knowledge of human operators. The GARIC architecture is applied to a cart-pole balancing system and demonstrates significant improvements in terms of the speed of learning and robustness to changes in the dynamic system's parameters over previous schemes for cart-pole balancing.

Synergies and strategies underlying normal and vestibulary deficient control of balance: implication for neuroprosthetic control.

PubMed

Allum, J H; Honegger, F

1993-01-01

Future developments of neuroprosthetic control will probably permit locomotion and posture to be maintained without the aid of crutches and will therefore require some form of balance control. Three fundamental questions will arise. First, the question of the location of imbalance-sensing transducers must be assessed. Secondly, the synergy, which is the relative amplitude and timing of muscle activity, and/or the strategy of joint torques required to re-establish a stable posture for different types of balance disturbances must be addressed. Thirdly, the control laws that map either trunk muscle activity or imbalance-sensing transducer outputs into multi-joint postural control of standing by paraplegic individuals must be generated. The most appropriate means of gathering the relevant information applicable to neuroprosthetic control systems is through the detailed analysis of normal and non-normal human models. In order to gain such detailed insights into normal balance control and its dependence on head angular and linear accelerations, the synergy and strategy of balance corrections in normal subjects or patients with vestibular deficits were investigated for two types of support surface perturbation, a dorsiflexion rotation (ROT) and a rearward translation (TRANS). These experimentally induced perturbations to upright stance were adjusted to cause equal amplitudes of ankle dorsiflexion, thus providing additional information about the role of lower leg proprioception on balance control. Synergies defined on the basis of peak cross-correlations of each recorded muscle's EMG to that of the largest muscle response were significantly different for TRANS and ROT. Translation synergies consisted of a sequential coactivation at several levels (soleus and abdominals some 30 msec before hamstrings, and trapezius some 15 msec before paraspinals), whereas the sequential activation of paraspinals and tibialis anterior dominated the balance synergy to ROT. Likewise, response strategies, defined using cross-correlations of joint torques, differed. That for TRANS was organised as a multi-link strategy with neck torques leading those of all other joints by 40 msec or more; hip joint lead ankle torques by 30 msec. That for ROT was organised around hip and ankle torques without a major correlation to neck torques. Vestibulary deficient subjects developed weaker synergies with respect to subjects with normal balance systems under eyes-open conditions and there was no clear synergy with eyes closed. Consequently, hip torques were delayed some 180 msec with respect to ankle torques, and correlations to neck torques were completely out of phase under eyes-closed conditions. Fundamental changes in TRANS synergies and strategies also occurred in vestibulary deficient subjects for eyes-open and eyes-closed conditions.(ABSTRACT TRUNCATED AT 400 WORDS)

Signatures of Long-Term Balancing Selection in Human Genomes

PubMed Central

de Filippo, Cesare; Teixeira, João C; Schmidt, Joshua M; Kleinert, Philip; Meyer, Diogo; Andrés, Aida M

2018-01-01

Abstract Balancing selection maintains advantageous diversity in populations through various mechanisms. Although extensively explored from a theoretical perspective, an empirical understanding of its prevalence and targets lags behind our knowledge of positive selection. Here, we describe the Non-central Deviation (NCD), a simple yet powerful statistic to detect long-term balancing selection (LTBS) that quantifies how close frequencies are to expectations under LTBS, and provides the basis for a neutrality test. NCD can be applied to a single locus or genomic data, and can be implemented considering only polymorphisms (NCD1) or also considering fixed differences with respect to an outgroup (NCD2) species. Incorporating fixed differences improves power, and NCD2 has higher power to detect LTBS in humans under different frequencies of the balanced allele(s) than other available methods. Applied to genome-wide data from African and European human populations, in both cases using chimpanzee as an outgroup, NCD2 shows that, albeit not prevalent, LTBS affects a sizable portion of the genome: ∼0.6% of analyzed genomic windows and 0.8% of analyzed positions. Significant windows (P < 0.0001) contain 1.6% of SNPs in the genome, which disproportionally fall within exons and change protein sequence, but are not enriched in putatively regulatory sites. These windows overlap ∼8% of the protein-coding genes, and these have larger number of transcripts than expected by chance even after controlling for gene length. Our catalog includes known targets of LTBS but a majority of them (90%) are novel. As expected, immune-related genes are among those with the strongest signatures, although most candidates are involved in other biological functions, suggesting that LTBS potentially influences diverse human phenotypes. PMID:29608730

Mental body transformation deficits in patients with chronic balance disorders.

PubMed

Allum, J H J; Langewitz, W; Sleptsova, M; Welge-Luessen, A; Honegger, F; Schatz, T H; Biner, C L; Maguire, C; Schmid, D A

2017-01-01

Movements may be generated consistent with imagining one's own body transformed or "disembodied" to a new position. Based on this concept we hypothesized that patients with objective balance deficits (obj-BD) would have altered neural transformation processes executing own body transformation (OBT) with functional consequences on balance control. Also we examined whether feeling unstable due to dizziness only (DO), without an obj-BD, also lead to an impaired OBT. 32 patients with chronic dizziness were tested: 16 patients with obj-BD as determined by balance control during a sequence of stance and gait tasks, 16 patients with dizziness only (DO). Patients and 9 healthy controls (HCs) were asked to replicate roll trunk movements of an instructor in a life size video: first, with spontaneously copied (SPO) or "embodied" egocentric movements (lean when the instructor leans); second, with "disembodied" or "transformed" movements (OBT) with exact replication - lean left when the instructor leans left. Onset latency of trunk roll, rise time to peak roll angle (interval), roll velocity, and amplitude were measured. SPO movements were always mirror-imaged. OBT task latencies were significantly longer and intervals shorter than for SPO tasks (p < 0.03) for all groups. Obj-BD but not DO patients had more errors for the OBT task and, compared to HCs, had longer onset latencies (p < 0.05) and smaller velocities (p < 0.003) and amplitudes (p < 0.001) in both the SPO and OBT tasks. Measures of DO patients were not significantly different from those of HCs. Mental transformation (OBT) and SPO copying abilities are impaired in subjects with obj-BD and dizziness, but not with dizziness only. We conclude that processing the neuropsychological representation of the human body (body schema) slows when balance control is deficient.

Automatic control of human thermal comfort with a liquid-cooled garment

NASA Technical Reports Server (NTRS)

Kuznetz, L. H.

1977-01-01

Water cooling in a liquid-cooled garment is used to maintain the thermal comfort of crewmembers during extravehicular activity. The feasibility of a simple control that will operate automatically to maintain the thermal comfort is established. Data on three test subjects are included to support the conclusion that heat balance can be maintained well within allowable medical limits. The controller concept was also successfully demonstrated for ground-based applications and shows potential for any tasks involving the use of liquid-cooled garments.

An Engineering Model of Human Balance Control—Part I: Biomechanical Model

PubMed Central

Barton, Joseph E.; Roy, Anindo; Sorkin, John D.; Rogers, Mark W.; Macko, Richard

2016-01-01

We developed a balance measurement tool (the balanced reach test (BRT)) to assess standing balance while reaching and pointing to a target moving in three-dimensional space according to a sum-of-sines function. We also developed a three-dimensional, 13-segment biomechanical model to analyze performance in this task. Using kinematic and ground reaction force (GRF) data from the BRT, we performed an inverse dynamics analysis to compute the forces and torques applied at each of the joints during the course of a 90 s test. We also performed spectral analyses of each joint's force activations. We found that the joints act in a different but highly coordinated manner to accomplish the tracking task—with individual joints responding congruently to different portions of the target disk's frequency spectrum. The test and the model also identified clear differences between a young healthy subject (YHS), an older high fall risk (HFR) subject before participating in a balance training intervention; and in the older subject's performance after training (which improved to the point that his performance approached that of the young subject). This is the first phase of an effort to model the balance control system with sufficient physiological detail and complexity to accurately simulate the multisegmental control of balance during functional reach across the spectra of aging, medical, and neurological conditions that affect performance. Such a model would provide insight into the function and interaction of the biomechanical and neurophysiological elements making up this system; and system adaptations to changes in these elements' performance and capabilities. PMID:26328608

Water as an essential nutrient: the physiological basis of hydration.

PubMed

Jéquier, E; Constant, F

2010-02-01

How much water we really need depends on water functions and the mechanisms of daily water balance regulation. The aim of this review is to describe the physiology of water balance and consequently to highlight the new recommendations with regard to water requirements. Water has numerous roles in the human body. It acts as a building material; as a solvent, reaction medium and reactant; as a carrier for nutrients and waste products; in thermoregulation; and as a lubricant and shock absorber. The regulation of water balance is very precise, as a loss of 1% of body water is usually compensated within 24 h. Both water intake and water losses are controlled to reach water balance. Minute changes in plasma osmolarity are the main factors that trigger these homeostatic mechanisms. Healthy adults regulate water balance with precision, but young infants and elderly people are at greater risk of dehydration. Dehydration can affect consciousness and can induce speech incoherence, extremity weakness, hypotonia of ocular globes, orthostatic hypotension and tachycardia. Human water requirements are not based on a minimal intake because it might lead to a water deficit due to numerous factors that modify water needs (climate, physical activity, diet and so on). Water needs are based on experimentally derived intake levels that are expected to meet the nutritional adequacy of a healthy population. The regulation of water balance is essential for the maintenance of health and life. On an average, a sedentary adult should drink 1.5 l of water per day, as water is the only liquid nutrient that is really essential for body hydration.

Neuronal control of energy homeostasis

PubMed Central

Gao, Qian; Horvath, Tamas L.

2013-01-01

Neuronal control of body energy homeostasis is the key mechanism by which animals and humans regulate their long-term energy balance. Various hypothalamic neuronal circuits (which include the hypothalamic melanocortin, midbrain dopamine reward and caudal brainstem autonomic feeding systems) control energy intake and expenditure to maintain body weight within a narrow range for long periods of a life span. Numerous peripheral metabolic hormones and nutrients target these structures providing feedback signals that modify the default “settings” of neuronal activity to accomplish this balance. A number of molecular genetic tools for manipulating individual components of brain energy homeostatic machineries, in combination with anatomical, electrophysiological, pharmacological and behavioral techniques, have been developed, which provide a means for elucidating the complex molecular and cellular mechanisms of feeding behavior and metabolism. This review will highlight some of these advancements and focus on the neuronal circuitries of energy homeostasis. PMID:18061579

Wavelet-frequency analysis for the detection of discontinuities in switched system models of human balance.

PubMed

Nema, Salam; Kowalczyk, Piotr; Loram, Ian

2017-01-01

This paper is concerned with detecting the presence of switching behavior in experimentally obtained posturographic data sets by means of a novel algorithm that is based on a combination of wavelet analysis and Hilbert transform. As a test-bed for the algorithm, we first use a switched model of human balance control during quiet standing with known switching behavior in four distinct configurations. We obtain a time-frequency representation of a signal generated by our model system. We are then able to detect manifestations of discontinuities (switchings) in the signal as spiking behavior. The frequency of switchings, measured by means of our algorithm and detected in our models systems, agrees with the frequency of spiking behavior found in the experimentally obtained posturographic data. Copyright © 2016. Published by Elsevier B.V.

A method to quantify the "cone of economy".

PubMed

Haddas, Ram; Lieberman, Isador H

2018-05-01

A non-randomized, prospective, concurrent control cohort study. The purpose of this study is to develop and evaluate a method to quantify the dimensions of the cone of economy (COE) and the energy expenditure associated with maintaining a balanced posture within the COE, scoliosis patients and compare them to matched non-scoliotic controls in a group of adult degenerative. Balance is defined as the ability of the human body to maintain its center of mass (COM) within the base of support with minimal postural sway. The cone of economy refers to the stable region of upright standing posture. The underlying assumption is that deviating outside one's individual cone challenges the balance mechanisms. Adult degenerative scoliosis (ADS) patients exhibit a variety of postural changes within their COE, involving the spine, pelvis and lower extremities, in their effort to compensate for the altered posture. Ten ADS patients and ten non-scoliotic volunteers performed a series of functional balance tests. The dimensions of the COE and the energy expenditure related to maintaining balance within the COE were measured using a human motion video capture system and dynamic surface electromyography. ADS patients presented more COM sway in the sagittal (ADS: 1.59 cm vs. H: 0.61 cm; p = 0.049) and coronal (ADS: 2.84 cm vs. H: 1.72 cm; p = 0.046) directions in comparison to the non-scoliotic control. ADS patients presented with more COM (ADS: 33.30 cm vs. H: 19.13 cm; p = 0.039) and head (ADS: 31.06 cm vs. H: 19.13 cm; p = 0.013) displacements in comparison to the non-scoliotic controls. Scoliosis patients expended more muscle activity to maintain static standing, as manifest by increased muscle activity in their erector spinae (ADS: 37.16 mV vs. H: 20.31 mV; p = 0.050), and gluteus maximus (ADS: 33.12 mV vs. H: 12.09 mV; p = 0.001) muscles. We were able to develop and evaluate a method that quantifies the COE boundaries, COM displacement, and amount of sway within the COE along with the energy expenditure for a specific patient. This method of COE measurement will enable spine care practitioners to objectively evaluate their patients in an effort to determine the most appropriate treatment options, and in objectively documenting the effectiveness of their intervention.

Can Man Control His Biological Evolution? A Symposium on Genetic Engineering. Genetic Engineering

ERIC Educational Resources Information Center

Ramsey, Paul

1972-01-01

Presented are issues related to genetic engineering. Increased knowledge of techniques to manipulate genes are apt to create confusion about moral values in relation to unborn babies and other living organisms on earth. Human beings may use this knowledge to disturb the balance maintained by nature. (PS)

Humans: still vital after all these years of automation.

PubMed

Parasuraman, Raja; Wickens, Christopher D

2008-06-01

The authors discuss empirical studies of human-automation interaction and their implications for automation design. Automation is prevalent in safety-critical systems and increasingly in everyday life. Many studies of human performance in automated systems have been conducted over the past 30 years. Developments in three areas are examined: levels and stages of automation, reliance on and compliance with automation, and adaptive automation. Automation applied to information analysis or decision-making functions leads to differential system performance benefits and costs that must be considered in choosing appropriate levels and stages of automation. Human user dependence on automated alerts and advisories reflects two components of operator trust, reliance and compliance, which are in turn determined by the threshold designers use to balance automation misses and false alarms. Finally, adaptive automation can provide additional benefits in balancing workload and maintaining the user's situation awareness, although more research is required to identify when adaptation should be user controlled or system driven. The past three decades of empirical research on humans and automation has provided a strong science base that can be used to guide the design of automated systems. This research can be applied to most current and future automated systems.

Basins of attraction in human balance

NASA Astrophysics Data System (ADS)

Smith, Victoria A.; Lockhart, Thurmon E.; Spano, Mark L.

2017-12-01

Falls are a recognized risk factor for unintentional injuries among older adults, accounting for a large proportion of fractures, emergency department visits, and urgent hospitalizations. Human balance and gait research traditionally uses linear or qualitative tests to assess and describe human motion; however, human motion is neither a simple nor a linear process. The objective of this research is to identify and to learn more about what factors affect balance using nonlinear dynamical techniques, such as basin boundaries. Human balance data was collected using dual force plates for leans using only ankle movements as well as for unrestricted leans. Algorithms to describe the basin boundary were created and compared based on how well each method encloses the experimental data points as well as captures the differences between the two leaning conditions.

Noise-Enhanced Human Balance Control

NASA Astrophysics Data System (ADS)

Priplata, Attila; Niemi, James; Salen, Martin; Harry, Jason; Lipsitz, Lewis A.; Collins, J. J.

2002-11-01

Noise can enhance the detection and transmission of weak signals in certain nonlinear systems, via a mechanism known as stochastic resonance. Here we show that input noise can be used to improve motor control in humans. Specifically, we show that the postural sway of both young and elderly individuals during quiet standing can be significantly reduced by applying subsensory mechanical noise to the feet. We further demonstrate with input noise a trend towards the reduction of postural sway in elderly subjects to the level of young subjects. These results suggest that noise-based devices, such as randomly vibrating shoe inserts, may enable people to overcome functional difficulties due to age-related sensory loss.

Loss of balance during balance beam walking elicits a multifocal theta band electrocortical response

PubMed Central

Gwin, Joseph T.; Makeig, Scott; Ferris, Daniel P.

2013-01-01

Determining the neural correlates of loss of balance during walking could lead to improved clinical assessment and treatment for individuals predisposed to falls. We used high-density electroencephalography (EEG) combined with independent component analysis (ICA) to study loss of balance during human walking. We examined 26 healthy young subjects performing heel-to-toe walking on a treadmill-mounted balance beam as well as walking on the treadmill belt (both at 0.22 m/s). ICA identified clusters of electrocortical EEG sources located in or near anterior cingulate, anterior parietal, superior dorsolateral-prefrontal, and medial sensorimotor cortex that exhibited significantly larger mean spectral power in the theta band (4–7 Hz) during walking on the balance beam compared with treadmill walking. Left and right sensorimotor cortex clusters produced significantly less power in the beta band (12–30 Hz) during walking on the balance beam compared with treadmill walking. For each source cluster, we also computed a normalized mean time/frequency spectrogram time locked to the gait cycle during loss of balance (i.e., when subjects stepped off the balance beam). All clusters except the medial sensorimotor cluster exhibited a transient increase in theta band power during loss of balance. Cluster spectrograms demonstrated that the first electrocortical indication of impending loss of balance occurred in the left sensorimotor cortex at the transition from single support to double support prior to stepping off the beam. These findings provide new insight into the neural correlates of walking balance control and could aid future studies on elderly individuals and others with balance impairments. PMID:23926037

Loss of balance during balance beam walking elicits a multifocal theta band electrocortical response.

PubMed

Sipp, Amy R; Gwin, Joseph T; Makeig, Scott; Ferris, Daniel P

2013-11-01

Determining the neural correlates of loss of balance during walking could lead to improved clinical assessment and treatment for individuals predisposed to falls. We used high-density electroencephalography (EEG) combined with independent component analysis (ICA) to study loss of balance during human walking. We examined 26 healthy young subjects performing heel-to-toe walking on a treadmill-mounted balance beam as well as walking on the treadmill belt (both at 0.22 m/s). ICA identified clusters of electrocortical EEG sources located in or near anterior cingulate, anterior parietal, superior dorsolateral-prefrontal, and medial sensorimotor cortex that exhibited significantly larger mean spectral power in the theta band (4-7 Hz) during walking on the balance beam compared with treadmill walking. Left and right sensorimotor cortex clusters produced significantly less power in the beta band (12-30 Hz) during walking on the balance beam compared with treadmill walking. For each source cluster, we also computed a normalized mean time/frequency spectrogram time locked to the gait cycle during loss of balance (i.e., when subjects stepped off the balance beam). All clusters except the medial sensorimotor cluster exhibited a transient increase in theta band power during loss of balance. Cluster spectrograms demonstrated that the first electrocortical indication of impending loss of balance occurred in the left sensorimotor cortex at the transition from single support to double support prior to stepping off the beam. These findings provide new insight into the neural correlates of walking balance control and could aid future studies on elderly individuals and others with balance impairments.

Effects of ageing on adaptation during vibratory stimulation of the calf and neck muscles.

PubMed

Patel, M; Fransson, P A; Magnusson, M

2009-01-01

The ability to adapt and habituate based on prior experiences is important for human movement control, fall prevention and for the ability to enhance performance during various human activities. However, little is known about the ability for the elderly to adapt to balance perturbations in the lateral direction. To determine whether adaptation, i.e., the ability to adjust postural control to handle balance perturbations better over time, differed in the elderly subjects compared with young subjects in the anteroposterior and lateral directions, and whether the site of the balance perturbation or the presence or absence of vision affected the response. Postural stability was measured as anteroposterior and lateral torque variance in a young group (n = 18 (9 female and 9 male), average age = 29.1 years) and an elderly group (n = 16 (5 female and 11 male), average age = 71.5 years) with eyes open and closed during balance perturbations from calf and neck vibrations. After a 30-s period of quiet stance, these vibrations were repeated over a period of 200 s, so the adaptive responses could be analyzed by splitting the data into 50-s periods. The adaptive responses in the anteroposterior and lateral directions were different. Adaptation in the anteroposterior direction occurred to an almost equal extent in the elderly and young, whereas adaptation in the lateral direction was markedly larger in the elderly in all tests except for neck vibration with eyes closed. Age, vision and vibration site were all influential factors for recorded body movements, but no significant combined effects were found. Balance perturbation instigates an adaptive response in the elderly in both the anteroposterior and lateral directions. However, during perturbation, age and vision are both very influential factors for the stability, thus associating the previously documented age-related decline in visual functioning with a higher risk of falls in this age range. (c) 2008 S. Karger AG, Basel.

Validation of measures from the smartphone sway balance application: a pilot study.

PubMed

Patterson, Jeremy A; Amick, Ryan Z; Thummar, Tarunkumar; Rogers, Michael E

2014-04-01

A number of different balance assessment techniques are currently available and widely used. These include both subjective and objective assessments. The ability to provide quantitative measures of balance and posture is the benefit of objective tools, however these instruments are not generally utilized outside of research laboratory settings due to cost, complexity of operation, size, duration of assessment, and general practicality. The purpose of this pilot study was to assess the value and validity of using software developed to access the iPod and iPhone accelerometers output and translate that to the measurement of human balance. Thirty healthy college-aged individuals (13 male, 17 female; age = 26.1 ± 8.5 years) volunteered. Participants performed a static Athlete's Single Leg Test protocol for 10 sec, on a Biodex Balance System SD while concurrently utilizing a mobile device with balance software. Anterior/posterior stability was recorded using both devices, described as the displacement in degrees from level, and was termed the "balance score." There were no significant differences between the two reported balance scores (p = 0.818. Mean balance score on the balance platform was 1.41 ± 0.90, as compared to 1.38 ± 0.72 using the mobile device. There is a need for a valid, convenient, and cost-effective tool to objectively measure balance. Results of this study are promising, as balance score derived from the Smartphone accelerometers were consistent with balance scores obtained from a previously validated balance system. However, further investigation is necessary as this version of the mobile software only assessed balance in the anterior/posterior direction. Additionally, further testing is necessary on a healthy populations and as well as those with impairment of the motor control system. Level 2b (Observational study of validity)(1.)

What can music tell us about social interaction?

PubMed

D'Ausilio, Alessandro; Novembre, Giacomo; Fadiga, Luciano; Keller, Peter E

2015-03-01

Humans are innately social creatures, but cognitive neuroscience, that has traditionally focused on individual brains, is only now beginning to investigate social cognition through realistic interpersonal interaction. Music provides an ideal domain for doing so because it offers a promising solution for balancing the trade-off between ecological validity and experimental control when testing cognitive and brain functions. Musical ensembles constitute a microcosm that provides a platform for parametrically modeling the complexity of human social interaction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Delegation to automaticity: the driving force for cognitive evolution?

PubMed

Shine, J M; Shine, R

2014-01-01

The ability to delegate control over repetitive tasks from higher to lower neural centers may be a fundamental innovation in human cognition. Plausibly, the massive neurocomputational challenges associated with the mastery of balance during the evolution of bipedality in proto-humans provided a strong selective advantage to individuals with brains capable of efficiently transferring tasks in this way. Thus, the shift from quadrupedal to bipedal locomotion may have driven the rapid evolution of distinctive features of human neuronal functioning. We review recent studies of functional neuroanatomy that bear upon this hypothesis, and identify ways to test our ideas.

Statically vs dynamically balanced gait: Analysis of a robotic exoskeleton compared with a human.

PubMed

Barbareschi, Giulia; Richards, Rosie; Thornton, Matt; Carlson, Tom; Holloway, Catherine

2015-01-01

In recent years exoskeletons able to replicate human gait have begun to attract growing popularity for both assistive and rehabilitative purposes. Although wearable robots often need the use of external support in order to maintain stability, the REX exoskeleton by REX Bionics is able to self-balance through the whole cycle. However this statically balanced gait presents important differences with the dynamically balanced gait of human subjects. This paper will examine kinematic and kinetic differences between the gait analysis performed on a subject wearing the REX exoskeleton and human gait analysis data as presented in literature. We will also provide an insight on the impact that these differences can have for both rehabilitative and assistive applications.

Artificial Balance: Restoration of the Vestibulo-Ocular Reflex in Humans with a Prototype Vestibular Neuroprosthesis

PubMed Central

Perez Fornos, Angelica; Guinand, Nils; van de Berg, Raymond; Stokroos, Robert; Micera, Silvestro; Kingma, Herman; Pelizzone, Marco; Guyot, Jean-Philippe

2014-01-01

The vestibular system plays a crucial role in the multisensory control of balance. When vestibular function is lost, essential tasks such as postural control, gaze stabilization, and spatial orientation are limited and the quality of life of patients is significantly impaired. Currently, there is no effective treatment for bilateral vestibular deficits. Research efforts both in animals and humans during the last decade set a solid background to the concept of using electrical stimulation to restore vestibular function. Still, the potential clinical benefit of a vestibular neuroprosthesis has to be demonstrated to pave the way for a translation into clinical trials. An important parameter for the assessment of vestibular function is the vestibulo-ocular reflex (VOR), the primary mechanism responsible for maintaining the perception of a stable visual environment while moving. Here we show that the VOR can be artificially restored in humans using motion-controlled, amplitude modulated electrical stimulation of the ampullary branches of the vestibular nerve. Three patients received a vestibular neuroprosthesis prototype, consisting of a modified cochlear implant providing vestibular electrodes. Significantly higher VOR responses were observed when the prototype was turned ON. Furthermore, VOR responses increased significantly as the intensity of the stimulation increased, reaching on average 79% of those measured in healthy volunteers in the same experimental conditions. These results constitute a fundamental milestone and allow us to envision for the first time clinically useful rehabilitation of patients with bilateral vestibular loss. PMID:24808890

People for sale: the need for a multidisciplinary approach towards human trafficking.

PubMed

Van Impe, K

2000-01-01

The article addresses the question of how to develop appropriate measures to tackle trafficking in women, based on the findings of a study of trafficking between the Philippines and Belgium. It argues that there is no easy or unidimensional solution to human trafficking, since it is influenced by a complex set of factors, often working in combination with one another. It concludes that control measures alone cannot stop the flow of trafficking in women and that a legal approach which relies solely on one type of legislation would be too narrow. An effective strategy must combine and balance punitive measures with protection of human rights, stricter border control and the removal of the root causes of irregular movements. Measures must be agreed and coordinated between origin, transit and receiving countries.

The Balance Control of Children with and without Hearing Impairment in Singapore--A Case Study

ERIC Educational Resources Information Center

Jernice, Tan Sing Yee; Nonis, Karen P.; Yi, Chow Jia

2011-01-01

The purpose of this study is to compare the balance control of participants with and without HI and also to investigate the effect of a Balance Programme (BP) on their balance control (HI; n = 2, M age = 7 years old). The BP consisted of six practice sessions of 45 minutes each. The Balance Tasks used to assess balance control were static Balance…

Clinical correlates of between-limb synchronization of standing balance control and falls during inpatient stroke rehabilitation.

PubMed

Mansfield, Avril; Mochizuki, George; Inness, Elizabeth L; McIlroy, William E

2012-01-01

Stroke-related sensorimotor impairment potentially contributes to impaired balance. Balance measures that reveal underlying limb-specific control problems, such as a measure of the synchronization of both lower limbs to maintain standing balance, may be uniquely informative about poststroke balance control. This study aimed to determine the relationships between clinical measures of sensorimotor control, functional balance, and fall risk and between-limb synchronization of balance control. The authors conducted a retrospective chart review of 100 individuals with stroke admitted to inpatient rehabilitation. Force plate-based measures were obtained while standing on 2 force plates, including postural sway (root mean square of anteroposterior and mediolateral center of pressure [COP]), stance load asymmetry (percentage of body weight borne on the less-loaded limb), and between-limb synchronization (cross-correlation of the COP recordings under each foot). Clinical measures obtained were motor impairment (Chedoke-McMaster Stroke Assessment), plantar cutaneous sensation, functional balance (Berg Balance Scale), and falls experienced in rehabilitation. Synchronization was significantly related to motor impairment and prospective falls, even when controlling for other force plate-based measures of standing balance control (ie, postural sway and stance load symmetry). Between-limb COP synchronization for standing balance appears to be a uniquely important index of balance control, independent of postural sway and load symmetry during stance.

Biomechanics of normal and pathological gait: implications for understanding human locomotor control.

PubMed

Winter, D A

1989-12-01

The biomechanical (kinetic) analysis of human gait reveals the integrated and detailed motor patterns that are essential in pinpointing the abnormal patterns in pathological gait. In a similar manner, these motor patterns (moments, powers, and EMGs) can be used to identify synergies and to validate theories of CNS control. Based on kinetic and EMG patterns for a wide range of normal subjects and cadences, evidence is presented that both supports and negates the central pattern generator theory of locomotion. Adaptive motor patterns that are evident in peripheral gait pathologies reinforce a strong peripheral rather than a central control. Finally, a three-component subtask theory of human gait is presented and is supported by reference to the motor patterns seen in a normal gait. The identified subtasks are (a) support (against collapse during stance); (b) dynamic balance of the upper body, also during stance; and (c) feedforward control of the foot trajectory to achieve safe ground clearance and a gentle heel contact.

Switching Adaptability in Human-Inspired Sidesteps: A Minimal Model.

PubMed

Fujii, Keisuke; Yoshihara, Yuki; Tanabe, Hiroko; Yamamoto, Yuji

2017-01-01

Humans can adapt to abruptly changing situations by coordinating redundant components, even in bipedality. Conventional adaptability has been reproduced by various computational approaches, such as optimal control, neural oscillator, and reinforcement learning; however, the adaptability in bipedal locomotion necessary for biological and social activities, such as unpredicted direction change in chase-and-escape, is unknown due to the dynamically unstable multi-link closed-loop system. Here we propose a switching adaptation model for performing bipedal locomotion by improving autonomous distributed control, where autonomous actuators interact without central control and switch the roles for propulsion, balancing, and leg swing. Our switching mobility model achieved direction change at any time using only three actuators, although it showed higher motor costs than comparable models without direction change. Our method of evaluating such adaptation at any time should be utilized as a prerequisite for understanding universal motor control. The proposed algorithm may simply explain and predict the adaptation mechanism in human bipedality to coordinate the actuator functions within and between limbs.

Review of first trial responses in balance control: influence of vestibular loss and Parkinson's disease.

PubMed

Allum, J H J; Tang, K-S; Carpenter, M G; Oude Nijhuis, L B; Bloem, B R

2011-04-01

The reaction to an unexpected balance disturbance is unpracticed, often startling and frequently associated with falls. This everyday situation can be reproduced in an experimental setting by exposing standing humans to sudden, unexpected and controlled movements of a support surface. In this review, we focus on the responses to the very first balance perturbation, the so-called first trial reactions (FTRs). Detailed analysis of FTRs may have important implications, both for clinical practice (providing new insights into the pathophysiological mechanisms underlying accidental falls in real life) and for understanding human physiology (what triggers and mediates these FTRs, and what is the relation to startle responses?). Several aspects of the FTRs have become clear. FTRs are characterized by an exaggerated postural reaction, with large EMG responses and co-contracting muscles in multiple body segments. This balance reaction is associated with marked postural instability (greater body sway to the perturbation). When the same perturbation is repeated, the size of the postural response habituates and the instability disappears. Other issues about FTRs remain largely unresolved, and these are addressed here. First, the functional role of FTRs is discussed. It appears that FTRs produce primarily increased trunk flexion during the multi-segmental response to postural perturbations, thus producing instability. Second, we consider which sensory signals trigger and modulate FTRs, placing specific emphasis on the role of vestibular signals. Surprisingly, vestibular signals appear to have no triggering role, but vestibular loss leads to excessive upper body FTRs due to loss of the normal modulatory influence. Third, we address the question whether startle-like responses are contributing to FTRs triggered by proprioceptive signals. We explain why this issue is still unresolved, mainly because of methodological difficulties involved in separating FTRs from 'pure' startle responses. Fourth, we review new work about the influence of perturbation direction on FTRs. Recent work from our group shows that the largest FTRs are obtained for toe-up support surface rotations which perturb the COM in the posterior direction. This direction corresponds to the directional preponderance for falls seen both in the balance laboratory and in daily life. Finally, we briefly touch upon clinical diagnostic issues, addressing whether FTRs (as opposed to habituated responses) could provide a more ecologically valid perspective of postural instability in patients compared to healthy subjects. We conclude that FTRs are an important source of information about human balance performance, both in health and disease. Future studies should no longer discard FTRs, but routinely include these in their analyses. Particular emphasis should be placed on the link between FTRs and everyday balance performance (including falls), and on the possible role played by startle reactions in triggering or modulating FTRs. Copyright © 2011 Elsevier B.V. All rights reserved.

The Fate of Trace Contaminants in a Crewed Spacecraft Cabin Environment

NASA Technical Reports Server (NTRS)

Perry, Jay L.; Kayatin, Matthew J.

2016-01-01

Trace chemical contaminants produced via equipment offgassing, human metabolic sources, and vehicle operations are removed from the cabin atmosphere by active contamination control equipment and incidental removal by other air quality control equipment. The fate of representative trace contaminants commonly observed in spacecraft cabin atmospheres is explored. Removal mechanisms are described and predictive mass balance techniques are reviewed. Results from the predictive techniques are compared to cabin air quality analysis results. Considerations are discussed for an integrated trace contaminant control architecture suitable for long duration crewed space exploration missions.

eEF2K/eEF2 Pathway Controls the Excitation/Inhibition Balance and Susceptibility to Epileptic Seizures.

PubMed

Heise, Christopher; Taha, Elham; Murru, Luca; Ponzoni, Luisa; Cattaneo, Angela; Guarnieri, Fabrizia C; Montani, Caterina; Mossa, Adele; Vezzoli, Elena; Ippolito, Giulio; Zapata, Jonathan; Barrera, Iliana; Ryazanov, Alexey G; Cook, James; Poe, Michael; Stephen, Michael Rajesh; Kopanitsa, Maksym; Benfante, Roberta; Rusconi, Francesco; Braida, Daniela; Francolini, Maura; Proud, Christopher G; Valtorta, Flavia; Passafaro, Maria; Sala, Mariaelvina; Bachi, Angela; Verpelli, Chiara; Rosenblum, Kobi; Sala, Carlo

2017-03-01

Alterations in the balance of inhibitory and excitatory synaptic transmission have been implicated in the pathogenesis of neurological disorders such as epilepsy. Eukaryotic elongation factor 2 kinase (eEF2K) is a highly regulated, ubiquitous kinase involved in the control of protein translation. Here, we show that eEF2K activity negatively regulates GABAergic synaptic transmission. Indeed, loss of eEF2K increases GABAergic synaptic transmission by upregulating the presynaptic protein Synapsin 2b and α5-containing GABAA receptors and thus interferes with the excitation/inhibition balance. This cellular phenotype is accompanied by an increased resistance to epilepsy and an impairment of only a specific hippocampal-dependent fear conditioning. From a clinical perspective, our results identify eEF2K as a potential novel target for antiepileptic drugs, since pharmacological and genetic inhibition of eEF2K can revert the epileptic phenotype in a mouse model of human epilepsy. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Opposing tissue-specific roles of angiotensin in the pathogenesis of obesity, and implications for obesity-related hypertension

PubMed Central

Littlejohn, Nicole K.

2015-01-01

Metabolic disease, specifically obesity, has now become the greatest challenge to improving cardiovascular health. The renin-angiotensin system (RAS) exists as both a circulating hormone system and as a local paracrine signaling mechanism within various tissues including the brain, kidney, and adipose, and this system is strongly implicated in cardiovascular health and disease. Growing evidence also implicates the RAS in the control of energy balance, supporting the concept that the RAS may be mechanistically involved in the pathogenesis of obesity and obesity hypertension. Here, we review the involvement of the RAS in the entire spectrum of whole organism energy balance mechanisms, including behaviors (food ingestion and spontaneous physical activity) and biological processes (digestive efficiency and both aerobic and nonaerobic resting metabolic rates). We hypothesize that opposing, tissue-specific effects of the RAS to modulate these various components of energy balance can explain the apparently paradoxical results reported by energy-balance studies that involve stimulating, versus disrupting, the RAS. We propose a model in which such opposing and tissue-specific effects of the RAS can explain the failure of simple, global RAS blockade to result in weight loss in humans, and hypothesize that obesity-mediated uncoupling of endogenous metabolic rate control mechanisms can explain the phenomenon of obesity-related hypertension. PMID:26491099

Tryptophan Depletion Promotes Habitual over Goal-Directed Control of Appetitive Responding in Humans.

PubMed

Worbe, Yulia; Savulich, George; de Wit, Sanne; Fernandez-Egea, Emilio; Robbins, Trevor W

2015-02-05

Optimal behavioral performance results from a balance between goal-directed and habitual systems of behavioral control, which are modulated by ascending monoaminergic projections. While the role of the dopaminergic system in behavioral control has been recently addressed, the extent to which changes in global serotonin neurotransmission could influence these 2 systems is still poorly understood. We employed the dietary acute tryptophan depletion procedure to reduce serotonin neurotransmission in 18 healthy volunteers and 18 matched controls. We used a 3-stage instrumental learning paradigm that includes an initial instrumental learning stage, a subsequent outcome-devaluation test, and a slip-of-action stage, which directly tests the balance between hypothetical goal-directed and habitual systems. We also employed a separate response inhibition control test to assess the behavioral specificity of the results. Acute tryptophan depletion produced a shift of behavioral performance towards habitual responding as indexed by performance on the slip-of-action test. Moreover, greater habitual responding in the acute tryptophan depletion group was predicted by a steeper decline in plasma tryptophan levels. In contrast, acute tryptophan depletion left intact the ability to use discriminative stimuli to guide instrumental choice as indexed by the instrumental learning stage and did not impair inhibitory response control. The major implication of this study is that serotonin modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. Our findings thus imply that diminished serotonin neurotransmission shifts behavioral control towards habitual responding. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Medical Devices Assess, Treat Balance Disorders

NASA Technical Reports Server (NTRS)

2009-01-01

You may have heard the phrase as difficult as walking and chewing gum as a joking way of referring to something that is not difficult at all. Just walking, however, is not all that simple physiologically speaking. Even standing upright is an undertaking requiring the complex cooperation of multiple motor and sensory systems including vision, the inner ear, somatosensation (sensation from the skin), and proprioception (the sense of the body s parts in relation to each other). The compromised performance of any of these elements can lead to a balance disorder, which in some form affects nearly half of Americans at least once in their lifetimes, from the elderly, to those with neurological or vestibular (inner ear) dysfunction, to athletes with musculoskeletal injuries, to astronauts returning from space. Readjusting to Earth s gravity has a significant impact on an astronaut s ability to balance, a result of the brain switching to a different "model" for interpreting sensory input in normal gravity versus weightlessness. While acclimating, astronauts can experience headaches, motion sickness, and problems with perception. To help ease the transition and study the effects of weightlessness on the body, NASA has conducted many investigations into post-flight balance control, realizing this research can help treat patients with balance disorders on Earth as well. In the 1960s, the NASA-sponsored Man Vehicle Laboratory at the Massachusetts Institute of Technology (MIT) studied the effects of prolonged space flight on astronauts. The lab s work intrigued MIT doctoral candidate Lewis Nashner, who began conducting NASA-funded research on human movement and balance under the supervision of Dr. Larry Young in the MIT Department of Aeronautics and Astronautics. In 1982, Nashner s work resulted in a noninvasive clinical technique for assessing the cooperative systems that allow the body to balance, commonly referred to as computerized dynamic posturography (CDP). CDP employs a series of dynamic protocols to isolate and assess balance function deficiencies. The technology was based on Nashner s novel, engineering-inspired concept of balance as an adaptable collaboration between multiple sensory and motor systems. CDP proved useful not only for examining astronauts, but for anyone suffering from balance problems. Today, CDP is the standard medical tool for objectively evaluating balance control.

Leptin and its potential interest in assisted reproduction cycles.

PubMed

Catteau, A; Caillon, H; Barrière, P; Denis, M G; Masson, D; Fréour, T

2016-04-01

Leptin, an adipose hormone, has been shown to control energy homeostasis and food intake, and exert many actions on female reproductive function. Consequently, this adipokine is a pivotal factor in studies conducted on animal models and humans to decipher the mechanisms behind the infertility often observed in obese women. A systematic PubMed search was conducted on all articles, published up to January 2015 and related to leptin and its actions on energy balance and reproduction, using the following key words: leptin, reproduction, infertility, IVF and controlled ovarian stimulation. The available literature was reviewed in order to provide an overview of the current knowledge on the physiological roles of leptin, its involvement in female reproductive function and its potential interest as a prognostic marker in IVF cycles. Animal and human studies show that leptin communicates nutritional status to the central nervous system and emerging evidence has demonstrated that leptin is involved in the control of reproductive functions by acting both directly on the ovaries and indirectly on the central nervous system. With respect to the clinical use of leptin as a biomarker in IVF cycles, a systematic review of the literature suggested its potential interest as a predictor of IVF outcome, as high serum and/or follicular fluid leptin concentrations have correlated negatively with cycle outcome. However, these preliminary results remain to be confirmed. Leptin regulates energy balance and female reproductive function, mainly through its action on hypothalamic-pituitary-ovarian function, whose molecular and cellular aspects are progressively being deciphered. Preliminary studies evaluating leptin as a biomarker in human IVF seem promising but need further confirmation. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

New generation of human machine interfaces for controlling UAV through depth-based gesture recognition

NASA Astrophysics Data System (ADS)

Mantecón, Tomás.; del Blanco, Carlos Roberto; Jaureguizar, Fernando; García, Narciso

2014-06-01

New forms of natural interactions between human operators and UAVs (Unmanned Aerial Vehicle) are demanded by the military industry to achieve a better balance of the UAV control and the burden of the human operator. In this work, a human machine interface (HMI) based on a novel gesture recognition system using depth imagery is proposed for the control of UAVs. Hand gesture recognition based on depth imagery is a promising approach for HMIs because it is more intuitive, natural, and non-intrusive than other alternatives using complex controllers. The proposed system is based on a Support Vector Machine (SVM) classifier that uses spatio-temporal depth descriptors as input features. The designed descriptor is based on a variation of the Local Binary Pattern (LBP) technique to efficiently work with depth video sequences. Other major consideration is the especial hand sign language used for the UAV control. A tradeoff between the use of natural hand signs and the minimization of the inter-sign interference has been established. Promising results have been achieved in a depth based database of hand gestures especially developed for the validation of the proposed system.

Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

NASA Technical Reports Server (NTRS)

Bloomberg, Jacob; Reschke, Millard; Mulavara, Ajitkumar; Wood, Scott; Serrador, Jorge; Fiedler, Matthew; Kofman, Igor; Peters, Brian T.; Cohen, Helen

2012-01-01

Crewmembers returning from long-duration space flight face significant challenges due to the microgravity-induced inappropriate adaptations in balance/sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain's ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/portable and provides imperceptible electrical stimulation to the balance organs of the human body. Stochastic resonance (SR) is a phenomenon whereby the response of a nonlinear system to a weak periodic input signal is optimized by the presence of a particular non-zero level of noise. This phenomenon of SR is based on the concept of maximizing the flow of information through a system by a non-zero level of noise. Application of imperceptible SR noise coupled with sensory input in humans has been shown to improve motor, cardiovascular, visual, hearing, and balance functions. SR increases contrast sensitivity and luminance detection; lowers the absolute threshold for tone detection in normal hearing individuals; improves homeostatic function in the human blood pressure regulatory system; improves noise-enhanced muscle spindle function; and improves detection of weak tactile stimuli using mechanical or electrical stimulation. SR noise has been shown to improve postural control when applied as mechanical noise to the soles of the feet, or when applied as electrical noise at the knee and to the back muscles. SR using imperceptible stochastic electrical stimulation of the vestibular system (stochastic vestibular stimulation, SVS) applied to normal subjects has shown to improve the degree of association between the weak input periodic signals introduced via venous blood pressure receptors and the heart-rate responses. Also, application of SVS over 24 hours improves the long-term heart-rate dynamics and motor responsiveness as indicated by daytime trunk activity measurements in patients with multi-system atrophy, Parkinson s disease, or both, including patients who were unresponsive to standard therapy for Parkinson s disease. Recent studies conducted at the NASA JSC Neurosciences Laboratories showed that imperceptible SVS, when applied to normal young healthy subjects, leads to significantly improved balance performance during postural disturbances on unstable compliant surfaces. These studies have shown the benefit of SR noise characteristic optimization with imperceptible SVS in the frequency range of 0-30 Hz, and amplitudes of stimulation have ranged from 100 to 400 microamperes.

Lower limb power rehabilitation (LLPR) using interactive video game for improvement of balance function in older people.

PubMed

Chen, Po-Yin; Wei, Shun-Hwa; Hsieh, Wan-Ling; Cheen, Jang-Rong; Chen, Liang-Kung; Kao, Chung-Lan

2012-01-01

Declined balance functions have adverse effects on elderly population. Lower limbs muscle power training is currently an emerging concept in rehabilitation on individuals with decreased balance and mobility. In this prospective, controlled study, we used a human-computer interactive video-game-based rehabilitation device (LLPR) for training of lower limb muscle power in the elderly. Forty (aged >65 years) individuals were recruited from the community. Twenty participants in the exercise group received 30-min training, twice a week, using the LLPR system. The LLPR system allows participants to perform fast speed sit-to-stand (STS) movements. Twenty age-matched participants in the control group performed slow speed STS movements, as well as strengthening and balance exercises, with the same frequency and duration. The results were compared after 12 sessions (6 weeks) of training. The mechanical and time parameters during STS movement were measured using the LLPR system. Modified falls efficacy scale (MFES), Tinetti Performance-Oriented Mobility Assessment (POMA), function reach test, five times sit to stand (FTSS) and Timed Up and Go (TUG) were administered to participants as clinical assessments. Results showed that in the exercise group, all the mechanical and time parameters showed significant improvement. In control group, only the maximal vertical ground reaction force (MVGRF) improved significantly. For clinical assessments (balance, mobility, and self-confidence), exercise group showed significantly better scores. The STS movements in video-game-based training mimic real life situations which may help to transfer the training effects into daily activities. The effectiveness of lower limb muscle training is worthy of further investigation. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Human Norovirus and Its Surrogates Induce Plant Immune Response in Arabidopsis thaliana and Lactuca sativa.

PubMed

Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E

2017-08-01

Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.

Criticality of Adaptive Control Dynamics

NASA Astrophysics Data System (ADS)

Patzelt, Felix; Pawelzik, Klaus

2011-12-01

We show, that stabilization of a dynamical system can annihilate observable information about its structure. This mechanism induces critical points as attractors in locally adaptive control. It also reveals, that previously reported criticality in simple controllers is caused by adaptation and not by other controller details. We apply these results to a real-system example: human balancing behavior. A model of predictive adaptive closed-loop control subject to some realistic constraints is introduced and shown to reproduce experimental observations in unprecedented detail. Our results suggests, that observed error distributions in between the Lévy and Gaussian regimes may reflect a nearly optimal compromise between the elimination of random local trends and rare large errors.

Monogenic IL-1 Mediated Autoinflammatory and Immunodeficiency Syndromes: Finding the Right Balance in Response to Danger Signals

PubMed Central

Henderson, Cailin; Goldbach-Mansky, Raphaela

2010-01-01

INTRODUCTION Interleukin -1 was the first cytokine identified and is a powerful inducer of fever and inflammation. The biologically active receptor for IL-1, shares signaling pathways with some pathogen recognition receptors, the toll like receptors (TLRs) which early on suggested an important role in innate immune function. DISCUSSION The discovery that some intracellular “danger receptors”, the NOD like receptors (NLRs) can assemble to form multimolecular platforms, the inflammasomes, that not only sense intracellular danger but also activate IL-1β, has provided the molecular basis for the integration of IL-1 as an early response mediator in danger recognition. The critical role of balancing IL-1 production and signaling in human disease has recently been demonstrated in rare human monogenic diseases with mutations that affect the meticulous control of IL-1 production, release and signaling by leading to decreased or increased TLR/IL-1 signaling. In diseases of decreased TLR/IL-1 signaling (IRAK-4 and MyD88 deficiencies) patients are at risk for infections with gram positive organisms; and in diseases of increased signaling, patients develop systemic autoinflammatory diseases (Cryopyrin associated periodic syndromes (CAPS), and deficiency of the IL-1 receptor antagonist (DIRA)). CONCLUSION Monogenic defects in a number of rare diseases that affect the balance of TLR/IL-1 signaling have provided us with opportunities to study the systemic effects of IL-1 in human diseases. The molecular defects in CAPS and DIRA provided a therapeutic rationale for targeting IL-1 and the impressive clinical results from IL-1 blocking therapies have undoubtedly confirmed the pivotal role of IL-1 in human disease and spurred the exploration of modifying IL-1 signaling in a number of genetically complex common human diseases. PMID:20353899

Balanced steady state free precession for arterial spin labeling MRI: Initial experience for blood flow mapping in human brain, retina, and kidney.

PubMed

Park, Sung-Hong; Wang, Danny J J; Duong, Timothy Q

2013-09-01

We implemented pseudo-continuous ASL (pCASL) with 2D and 3D balanced steady state free precession (bSSFP) readout for mapping blood flow in the human brain, retina, and kidney, free of distortion and signal dropout, which are typically observed in the most commonly used echo-planar imaging acquisition. High resolution functional brain imaging in the human visual cortex was feasible with 3D bSSFP pCASL. Blood flow of the human retina could be imaged with pCASL and bSSFP in conjunction with a phase cycling approach to suppress the banding artifacts associated with bSSFP. Furthermore, bSSFP based pCASL enabled us to map renal blood flow within a single breath hold. Control and test-retest experiments suggested that the measured blood flow values in retina and kidney were reliable. Because there is no specific imaging tool for mapping human retina blood flow and the standard contrast agent technique for mapping renal blood flow can cause problems for patients with kidney dysfunction, bSSFP based pCASL may provide a useful tool for the diagnosis of retinal and renal diseases and can complement existing imaging techniques. Copyright © 2013 Elsevier Inc. All rights reserved.

Posture and cognition in the elderly: interaction and contribution to the rehabilitation strategies.

PubMed

Borel, L; Alescio-Lautier, B

2014-01-01

In this paper we review the effects of aging on sensory systems and their impact on posture, balance and gait. We also address cognitive aging and attempt to specify which altered cognitive functions negatively impact balance and walking. The role of cognition in postural control is tested with dual-task experiments. This situation results in deleterious effects due to an attentional overload. Given the human cognitive system has limited capacities, we propose that simultaneously performing two tasks depends on the capacity of each individual to perform these tasks on a continuum between automatic execution to highly controlled performance. A level of maximum control exceeds the subject's attentional capacity, which makes it impossible to perform both tasks simultaneously. The subject therefore prioritizes one of the tasks. We use representative dual-task studies from the literature to illustrate the relationship between the different cognitive components and their impact on the control of posture and gait in elderly subjects with altered cognitive capacities and with elderly subjects who are fallers or who have altered sensory-motor capacities. Recently this postural-cognitive relationship was addressed with a new approach. We report how cognitive training can improve dual-task management and we attempt to define the cognitive mechanisms that may be responsible for better postural balance. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Collaborative real-time scheduling of multiple PTZ cameras for multiple object tracking in video surveillance

NASA Astrophysics Data System (ADS)

Liu, Yu-Che; Huang, Chung-Lin

2013-03-01

This paper proposes a multi-PTZ-camera control mechanism to acquire close-up imagery of human objects in a surveillance system. The control algorithm is based on the output of multi-camera, multi-target tracking. Three main concerns of the algorithm are (1) the imagery of human object's face for biometric purposes, (2) the optimal video quality of the human objects, and (3) minimum hand-off time. Here, we define an objective function based on the expected capture conditions such as the camera-subject distance, pan tile angles of capture, face visibility and others. Such objective function serves to effectively balance the number of captures per subject and quality of captures. In the experiments, we demonstrate the performance of the system which operates in real-time under real world conditions on three PTZ cameras.

An Approach to Improving Science Knowledge about Energy Balance and Nutrition among Elementary- and Middle-School Students

ERIC Educational Resources Information Center

Moreno, Nancy P.; Denk, James P.; Roberts, J. Kyle; Tharp, Barbara Z.; Bost, Michelle; Thomson, William A.

2004-01-01

Unhealthy diets, lack of fitness, and obesity are serious problems in the United States. The Centers for Disease Control, Surgeon General, and Department of Health and Human Services are calling for action to address these problems. Scientists and educators at Baylor College of Medicine and the National Space Biomedical Research Institute teamed…

Oxytocin and potential benefits for obesity treatment.

PubMed

Olszewski, Pawel K; Klockars, Anica; Levine, Allen S

2017-10-01

Laboratory animal experiments have consistently shown that oxytocin causes early termination of food intake, thereby promoting a decrease in body weight in a long term. Recent studies have also assessed some of oxytocin's effects on appetite and energy balance in humans. The present study examines the findings of the key basic research and of the few clinical studies published thus far in the context of potential benefits and challenges stemming from the use of oxytocin in obese patients. Basic research indicates the involvement of oxytocin in satiety, processing, in reducing a drive to eat for pleasure and because of psychosocial factors. Although the results of clinical studies are very scarce, they suggest that oxytocin administered intranasally in humans decreases energy-induced and reward-induced eating, supports cognitive control of food choices, and improves glucose homeostasis, and its effectiveness may be BMI dependent. Despite the wealth of basic research showing broad anorexigenic effects of oxytocin, clinical studies on oxytocin's therapeutic potential in obesity, are still in their infancy. Future implementation of oxytocin-based pharmacological strategies in controlling energy balance will likely depend on our ability to integrate diverse behavioral and metabolic effects of oxytocin in obesity treatment regimens.

Does dynamic stability govern propulsive force generation in human walking?

PubMed Central

Browne, Michael G.

2017-01-01

Before succumbing to slower speeds, older adults may walk with a diminished push-off to prioritize stability over mobility. However, direct evidence for trade-offs between push-off intensity and balance control in human walking, independent of changes in speed, has remained elusive. As a critical first step, we conducted two experiments to investigate: (i) the independent effects of walking speed and propulsive force (FP) generation on dynamic stability in young adults, and (ii) the extent to which young adults prioritize dynamic stability in selecting their preferred combination of walking speed and FP generation. Subjects walked on a force-measuring treadmill across a range of speeds as well as at constant speeds while modulating their FP according to a visual biofeedback paradigm based on real-time force measurements. In contrast to improvements when walking slower, walking with a diminished push-off worsened dynamic stability by up to 32%. Rather, we find that young adults adopt an FP at their preferred walking speed that maximizes dynamic stability. One implication of these findings is that the onset of a diminished push-off in old age may independently contribute to poorer balance control and precipitate slower walking speeds. PMID:29291129

Does dynamic stability govern propulsive force generation in human walking?

PubMed

Browne, Michael G; Franz, Jason R

2017-11-01

Before succumbing to slower speeds, older adults may walk with a diminished push-off to prioritize stability over mobility. However, direct evidence for trade-offs between push-off intensity and balance control in human walking, independent of changes in speed, has remained elusive. As a critical first step, we conducted two experiments to investigate: (i) the independent effects of walking speed and propulsive force ( F P ) generation on dynamic stability in young adults, and (ii) the extent to which young adults prioritize dynamic stability in selecting their preferred combination of walking speed and F P generation. Subjects walked on a force-measuring treadmill across a range of speeds as well as at constant speeds while modulating their F P according to a visual biofeedback paradigm based on real-time force measurements. In contrast to improvements when walking slower, walking with a diminished push-off worsened dynamic stability by up to 32%. Rather, we find that young adults adopt an F P at their preferred walking speed that maximizes dynamic stability. One implication of these findings is that the onset of a diminished push-off in old age may independently contribute to poorer balance control and precipitate slower walking speeds.

Viability of human periodontal ligament fibroblasts in milk, Hank's balanced salt solution and coconut water as storage media.

PubMed

Souza, B D M; Lückemeyer, D D; Reyes-Carmona, J F; Felippe, W T; Simões, C M O; Felippe, M C S

2011-02-01

To evaluate the effectiveness of various storage media at 5 °C for maintaining the viability of human periodontal ligament fibroblasts (PDLF). Plates with PDLF were soaked in recently prepared Hank's balanced salt solution (HBSS), skimmed milk, whole milk, Save-A-Tooth(®) system's HBSS (Save), natural coconut water, industrialized coconut water or tap water (negative control) at 5 °C for 3, 6, 24, 48, 72, 96 and 120 h. Minimum essential medium (MEM) at 37 °C served as the positive control. PDL cell viability was determined by MTT assay. Data were statistically analysed by Kruskal-Wallis test complemented by the Scheffé test (α=5%). The greatest number of viable cells was observed for MEM. Skimmed and whole milk, followed by natural coconut water and HBSS, were the most effective media in maintaining cell viability (P<0.05). From 24 to 120 h, Save, industrialized coconut water and tap water were the worst storage media. Skimmed and whole milk had the greatest capacity to maintain PDLF viability when compared with natural coconut water, HBSS, Save, industrialized coconut water and tap water. © 2010 International Endodontic Journal.

Cost-Benefit Arbitration Between Multiple Reinforcement-Learning Systems.

PubMed

Kool, Wouter; Gershman, Samuel J; Cushman, Fiery A

2017-09-01

Human behavior is sometimes determined by habit and other times by goal-directed planning. Modern reinforcement-learning theories formalize this distinction as a competition between a computationally cheap but inaccurate model-free system that gives rise to habits and a computationally expensive but accurate model-based system that implements planning. It is unclear, however, how people choose to allocate control between these systems. Here, we propose that arbitration occurs by comparing each system's task-specific costs and benefits. To investigate this proposal, we conducted two experiments showing that people increase model-based control when it achieves greater accuracy than model-free control, and especially when the rewards of accurate performance are amplified. In contrast, they are insensitive to reward amplification when model-based and model-free control yield equivalent accuracy. This suggests that humans adaptively balance habitual and planned action through on-line cost-benefit analysis.

Peripheral metabolic actions of leptin.

PubMed

Muoio, Deborah M; Lynis Dohm, G

2002-12-01

The adipocyte-derived hormone, leptin, regulates food intake and systemic fuel metabolism; ob /ob mice, which lack functional leptin, exhibit an obesity syndrome that is similar to morbid obesity in humans. Leptin receptors are expressed most abundantly in the brain but are also present in several peripheral tissues. The role of leptin in controlling energy homeostasis has thus far focused on brain receptors and neuroendocrine pathways that regulate feeding behaviour and sympathetic nervous system activity. This chapter focuses on mounting evidence that leptin's effects on energy balance are also mediated by direct peripheral actions on key metabolic organs such as skeletal muscle, liver, pancreas and adipose tissue. Strong evidence indicates that peripheral leptin receptors regulate cellular lipid balance, favouring beta-oxidation over triacylglycerol storage. There are data to indicate that peripheral leptin also modulates glucose metabolism and insulin action; however, its precise role in controlling gluco-regulatory pathways remains uncertain and requires further investigation.

Fall proof: improving mobility and balance Elizabeth Best-Martini Fall proof: improving mobility and balance and Kim A Botenhagen-Di Genova Human Kinetics £24.50 0 73603 687 3 0736036873 Debra Rose Human Kinetics £38 0 73604 088 9 0736040889.

PubMed

2003-09-01

A structured balance and mobility-training programme specifically designed to reduce physical frailty and the rising incidence of falls among older people. This practical manual blends theory into practical applications and covers an introduction to the body systems, balance assessments and a discussion of contemporary motor learning principles. Tel: Customer Services 0113 255 5665. Email: hk@hkeurope.com.

Acute effect of ephedrine on 24-h energy balance

NASA Technical Reports Server (NTRS)

Shannon, J. R.; Gottesdiener, K.; Jordan, J.; Chen, K.; Flattery, S.; Larson, P. J.; Candelore, M. R.; Gertz, B.; Robertson, D.; Sun, M.

1999-01-01

Ephedrine is used to help achieve weight control. Data on its true efficacy and mechanisms in altering energy balance in human subjects are limited. We aimed to determine the acute effect of ephedrine on 24-h energy expenditure, mechanical work and urinary catecholamines in a double-blind, randomized, placebo-controlled, two-period crossover study. Ten healthy volunteers were given ephedrine (50 mg) or placebo thrice daily during each of two 24-h periods (ephedrine and placebo) in a whole-room indirect calorimeter, which accurately measures minute-by-minute energy expenditure and mechanical work. Measurements were taken of 24-h energy expenditure, mechanical work, urinary catecholamines and binding of (+/-)ephedrine in vitro to human beta1-, beta2- and beta3-adrenoreceptors. Twenty-four-hour energy expenditure was 3.6% greater (8965+/-1301 versus 8648+/-1347 kJ, P<0.05) with ephedrine than with placebo, but mechanical work was not different between the ephedrine and placebo periods. Noradrenaline excretion was lower with ephedrine (0.032+/-0.011 microg/mg creatinine) compared with placebo (0.044+/-0.012 microg/mg creatinine) (P<0.05). (+/-)Ephedrine is a relatively weak partial agonist of human beta1- and beta2-adrenoreceptors, and had no detectable activity at human beta3-adrenoreceptors. Ephedrine (50 mg thrice daily) modestly increases energy expenditure in normal human subjects. A lack of binding of ephedrine to beta3-adrenoreceptors and the observed decrease in urinary noradrenaline during ephedrine treatment suggest that the thermogenic effect of ephedrine results from direct beta1-/beta2-adrenoreceptor agonism. An indirect beta3-adrenergic effect through the release of noradrenaline seems unlikely as urinary noradrenaline decreased significantly with ephedrine.

Human performance under two different command and control paradigms.

PubMed

Walker, Guy H; Stanton, Neville A; Salmon, Paul M; Jenkins, Daniel P

2014-05-01

The paradoxical behaviour of a new command and control concept called Network Enabled Capability (NEC) provides the motivation for this paper. In it, a traditional hierarchical command and control organisation was pitted against a network centric alternative on a common task, played thirty times, by two teams. Multiple regression was used to undertake a simple form of time series analysis. It revealed that whilst the NEC condition ended up being slightly slower than its hierarchical counterpart, it was able to balance and optimise all three of the performance variables measured (task time, enemies neutralised and attrition). From this it is argued that a useful conceptual response is not to consider NEC as an end product comprised of networked computers and standard operating procedures, nor to regard the human system interaction as inherently stable, but rather to view it as a set of initial conditions from which the most adaptable component of all can be harnessed: the human. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Functional balance between neuraminidase and haemagglutinin in influenza viruses.

PubMed

Gaymard, A; Le Briand, N; Frobert, E; Lina, B; Escuret, V

2016-12-01

Seasonal influenza A and B viruses are important human pathogens responsible for significant morbidity and mortality worldwide. In addition, influenza A zoonotic viruses are a constant pandemic threat. These viruses present two major surface glycoproteins: the haemagglutinin (HA) and the neuraminidase (NA). These two glycoproteins both recognize the sialic acid and have complementary activities, the HA binds the sialic acid through its receptor-binding site, the NA is a receptor-destroying enzyme that cleaves α2-3 and α2-6-linked sialic acids. Therefore, the functional HA/NA balance is a critical factor for a good viral fitness and plays a major role in overcoming the host barrier and the efficiency of sustained human-to-human transmission. Although the two glycoproteins are in constant evolution, the HA/NA balance seems to remain stable in human viruses because an optimal balance is required to maintain good viral fitness. Understanding the evolution of influenza viruses requires an in-depth exploration of the HA/NA balance. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Designing for flexible interaction between humans and automation: delegation interfaces for supervisory control.

PubMed

Miller, Christopher A; Parasuraman, Raja

2007-02-01

To develop a method enabling human-like, flexible supervisory control via delegation to automation. Real-time supervisory relationships with automation are rarely as flexible as human task delegation to other humans. Flexibility in human-adaptable automation can provide important benefits, including improved situation awareness, more accurate automation usage, more balanced mental workload, increased user acceptance, and improved overall performance. We review problems with static and adaptive (as opposed to "adaptable") automation; contrast these approaches with human-human task delegation, which can mitigate many of the problems; and revise the concept of a "level of automation" as a pattern of task-based roles and authorizations. We argue that delegation requires a shared hierarchical task model between supervisor and subordinates, used to delegate tasks at various levels, and offer instruction on performing them. A prototype implementation called Playbook is described. On the basis of these analyses, we propose methods for supporting human-machine delegation interactions that parallel human-human delegation in important respects. We develop an architecture for machine-based delegation systems based on the metaphor of a sports team's "playbook." Finally, we describe a prototype implementation of this architecture, with an accompanying user interface and usage scenario, for mission planning for uninhabited air vehicles. Delegation offers a viable method for flexible, multilevel human-automation interaction to enhance system performance while maintaining user workload at a manageable level. Most applications of adaptive automation (aviation, air traffic control, robotics, process control, etc.) are potential avenues for the adaptable, delegation approach we advocate. We present an extended example for uninhabited air vehicle mission planning.

Passive dynamics is a good basis for robot design and control, not!

NASA Astrophysics Data System (ADS)

Ruina, Andy

Many airplanes can, or nearly can, glide stably without control. So, it seems natural that the first successful powered flight followed from mastery of gliding. Many bicycles can, or nearly can, balance themselves when in motion. Bicycle design seems to have evolved to gain this feature. Also, we can make toys and 'robots' that, like a stable glider or coasting bicycle, stably walk without motors or control in a remarkably human-like way. Again, it seems to make sense to use `passive-dynamics' as a core for developing the control of walking robots and to gain understanding of the control of walking people. That's what I used to think. But, so far, this has not led to robust walking robots. What about human evolution? We didn't evolve dynamic bodies and then learn to control them. Rather, people had elaborate control systems way back when we were fish and even worms. However: if control is paramount, why is it that uncontrolled passive-dynamic walkers walk so much like humans? It seems that energy optimal, yet robust, control, perhaps a proxy for evolutionary development, arrives at solutions that have some features in common with passive-dynamics. Rather than thinking of good powered walking as passive walking with a small amount of control added, I now think of good powered walking, human or robotic, as highly controlled, while optimized for, in part, minimal actuator use. Thus, much of the motor effort, always at the ready, is usually titrated out.

A New Powered Lower Limb Prosthesis Control Framework Based on Adaptive Dynamic Programming.

PubMed

Wen, Yue; Si, Jennie; Gao, Xiang; Huang, Stephanie; Huang, He Helen

2017-09-01

This brief presents a novel application of adaptive dynamic programming (ADP) for optimal adaptive control of powered lower limb prostheses, a type of wearable robots to assist the motor function of the limb amputees. Current control of these robotic devices typically relies on finite state impedance control (FS-IC), which lacks adaptability to the user's physical condition. As a result, joint impedance settings are often customized manually and heuristically in clinics, which greatly hinder the wide use of these advanced medical devices. This simulation study aimed at demonstrating the feasibility of ADP for automatic tuning of the twelve knee joint impedance parameters during a complete gait cycle to achieve balanced walking. Given that the accurate models of human walking dynamics are difficult to obtain, the model-free ADP control algorithms were considered. First, direct heuristic dynamic programming (dHDP) was applied to the control problem, and its performance was evaluated on OpenSim, an often-used dynamic walking simulator. For the comparison purposes, we selected another established ADP algorithm, the neural fitted Q with continuous action (NFQCA). In both cases, the ADP controllers learned to control the right knee joint and achieved balanced walking, but dHDP outperformed NFQCA in this application during a 200 gait cycle-based testing.

Variation in the levels of pregnancy-specific beta-1-glycoprotein in maternal serum from chromosomally abnormal pregnancies.

PubMed

Graham, G W; Crossley, J A; Aitken, D A; Connor, J M

1992-06-01

Human pregnancy-specific beta-1-glycoprotein (SP1) was assayed retrospectively in stored maternal serum (MS) samples from 82 chromosomally abnormal pregnancies and 377 matched controls. The median MSSP1 concentration in 48 Down's syndrome pregnancies was significantly elevated at 1.17 multiples of the control median (MOM), and significantly reduced (0.5 MOM) in a group of eight cases of unbalanced translocations. There was no significant difference in median SP1 concentrations in cases of trisomy 18, trisomy 13, balanced translocations, or sex chromosome abnormalities. A comparison with human chorionic gonadotrophin results in the same series of samples indicates that SP1 is a less sensitive predictor of Down's syndrome pregnancies.

[Studies of time-course changes in human body balance after ingestion of long-acting hypnotics].

PubMed

Nakamura, Masahiro; Ishii, Masanori; Niwa, Yoji; Yamazaki, Momoko; Ito, Hiroshi

2004-02-01

Falling accidents are a serious nocosomial problem, with balance disorders after the ingestion of hypnotics said to be a cause. Based on the results of animal studies, it was postulated that this problem involves the muscle relaxation that is a pharmacological effect of benzodiazepines (BZP). No reports have, to our knowledge, been made of time-course changes in human body balance after ingestion of hypnotics. Accordingly, we used quazepam (Doral), a long-acting hypnotic considered to show comparatively weak muscle relaxation, to study static balance after drug ingestion in human volunteers. Briefly, informed consent was obtained from 8 healthy adults, then a gait analytic system (Gangas) was used to test static balance after drug ingestion (Mann and Romberg tests). We also measured circulating drug concentration over time. Our results showed that balance disorders occurred after quazepam ingestion with an unstable posture particularly striking. Given the function of quazepam receptors, it is difficult to surmise that balance disorders after drug ingestion were due to the drug's muscle relaxation. We surmised that inhibition from the central nervous system in connection with nerves awakening was involved. We found a strong correlation between the manifestation of balance disorders after drug ingestion and circulating drug concentration.

Asymmetries in reactive and anticipatory balance control are of similar magnitude in Parkinson's disease patients.

PubMed

Boonstra, Tjitske A; van Kordelaar, Joost; Engelhart, Denise; van Vugt, Jeroen P P; van der Kooij, Herman

2016-01-01

Many Parkinson's disease (PD) patients show asymmetries in balance control during quiet stance and in response to perturbations (i.e., reactive balance control) in the sagittal plane. In addition, PD patients show a reduced ability to anticipate to self-induced disturbances, but it is not clear whether these anticipatory responses can be asymmetric too. Furthermore, it is not known how reactive balance control and anticipatory balance control are related in PD patients. Therefore, we investigated whether reactive and anticipatory balance control are asymmetric to the same extent in PD patients. 14 PD patients and 10 controls participated. Reactive balance control (RBC) was investigated by applying external platform and force perturbations and relating the response of the left and right ankle torque to the body sway angle at the excited frequencies. Anticipatory postural adjustments (APAs) were investigated by determining the increase in the left and right ankle torque just before the subjects released a force exerted with the hands against a force sensor. The symmetry ratio between the contribution of the left and right ankle was used to express the asymmetry in reactive and anticipatory balance control; the correlation between the two ratio's was investigated with Spearman's rank correlation coefficients. PD patients were more asymmetric in anticipatory (p=0.026) and reactive balance control (p=0.004) compared to controls and the symmetry ratios were significantly related (ρ=0.74; p=0.003) in PD patients. These findings suggest that asymmetric reactive balance control during bipedal stance may share a common pathophysiology with asymmetries in the anticipation of voluntary perturbations during, for instance, gait initiation. Copyright © 2015 Elsevier B.V. All rights reserved.

The Role of Ankle Proprioception for Balance Control in relation to Sports Performance and Injury.

PubMed

Han, Jia; Anson, Judith; Waddington, Gordon; Adams, Roger; Liu, Yu

2015-01-01

Balance control improvement is one of the most important goals in sports and exercise. Better balance is strongly positively associated with enhanced athletic performance and negatively associated with lower limb sports injuries. Proprioception plays an essential role in balance control, and ankle proprioception is arguably the most important. This paper reviews ankle proprioception and explores synergies with balance control, specifically in a sporting context. Central processing of ankle proprioceptive information, along with other sensory information, enables integration for balance control. When assessing ankle proprioception, the most generalizable findings arise from methods that are ecologically valid, allow proprioceptive signals to be integrated with general vision in the central nervous system, and reflect the signal-in-noise nature of central processing. Ankle proprioceptive intervention concepts driven by such a central processing theory are further proposed and discussed for the improvement of balance control in sport.

The Role of Ankle Proprioception for Balance Control in relation to Sports Performance and Injury

PubMed Central

Han, Jia; Waddington, Gordon; Adams, Roger; Liu, Yu

2015-01-01

Balance control improvement is one of the most important goals in sports and exercise. Better balance is strongly positively associated with enhanced athletic performance and negatively associated with lower limb sports injuries. Proprioception plays an essential role in balance control, and ankle proprioception is arguably the most important. This paper reviews ankle proprioception and explores synergies with balance control, specifically in a sporting context. Central processing of ankle proprioceptive information, along with other sensory information, enables integration for balance control. When assessing ankle proprioception, the most generalizable findings arise from methods that are ecologically valid, allow proprioceptive signals to be integrated with general vision in the central nervous system, and reflect the signal-in-noise nature of central processing. Ankle proprioceptive intervention concepts driven by such a central processing theory are further proposed and discussed for the improvement of balance control in sport. PMID:26583139

Maintenance of CO2 level in a BLSS by controlling solid waste treatment unit

NASA Astrophysics Data System (ADS)

Dong, Yingying; Li, Leyuan; Liu, Hong; Fu, Yuming; Xie, Beizhen; Hu, Dawei; Liu, Dianlei; Dong, Chen; Liu, Guanghui

A bioregenerative life support system (BLSS) is an artificial closed ecosystem for providing basic human life support for long-duration, far-distance space explorations such as lunar bases. In such a system, the circulation of gases is one of the main factor for realizing a higher closure degree. O2 produced by higher plants goes to humans, as well as microorganisms for the treatment of inedible plant biomass and human wastes; CO2 produced by the crew and microorganisms is provided for plant growth. During this process, an excessively high CO2 level will depress plant growth and may be harmful to human health; and if the CO2 level is too low, plant growth will also be affected. Thus, keeping the balance between CO2 and O2 levels is a crucial problem. In this study, a high-efficiency, controllable solid waste treatment unit is constructed, which adopts microbial fermentation of the mixture of inedible biomass and human wastes. CO2 production during the fermentation process is controlled by adjusting fermentation temperature, aeration rate, moisture, etc., so as to meet the CO2 requirement of plants

Human balancing of an inverted pendulum with a compliant linkage: neural control by anticipatory intermittent bias

PubMed Central

Lakie, Martin; Caplan, Nicholas; Loram, Ian D

2003-01-01

These experiments were prompted by the recent discovery that the intrinsic stiffness of the ankle is inadequate to stabilise passively the body in standing. Our hope was that showing how a large inverted pendulum was manually balanced with low intrinsic stiffness would elucidate the active control of human standing. The results show that the pendulum can be satisfactorily stabilised when intrinsic stiffness is low. Analysis of sway size shows that intrinsic stiffness actually plays little part in stabilisation. The sway duration is also substantially independent of intrinsic stiffness. This suggests that the characteristic sway of the pendulum, rather than being dictated by stiffness and inertia, may result from the control pattern of hand movements. The key points revealed by these experiments are that with low intrinsic stiffness the hand provides pendulum stability by intermittently altering the bias of the spring and, on average, the hand moves in opposition to the load. The results lead to a new and testable hypothesis; namely that in standing, the calf muscle shortens as the body sways forward and lengthens as it sways backwards. These findings are difficult to reconcile with stretch reflex control of the pendulum and are of particular relevance to standing. They may also be relevant to postural maintenance in general whenever the CNS controls muscles which operate through compliant linkages. The results also suggest that in standing, rather than providing passive stability, the intrinsic stiffness acts as an energy efficient buffer which provides decoupling between muscle and body. PMID:12832494

Study I: effects of 0.06% and 0.10% blood alcohol concentration on human postural control.

PubMed

Modig, F; Patel, M; Magnusson, M; Fransson, P A

2012-03-01

Alcohol intoxication causes many accidental falls presented at emergency departments, with the injury severity often related to level of blood alcohol concentration (BAC). One way to evaluate the decline in postural control and the fall risk is to assess standing stability when challenged. The study objective was to comprehensively investigate alcohol-related impairments on postural control and adaptive motor learning at specific BAC levels. Effects of alcohol intoxication at 0.06% and 0.10% BAC were examined with posturography when unperturbed or perturbed by calf vibration. Twenty-five participants (mean age 25.1 years) were investigated standing with either eyes open or closed. Our results revealed several significant findings: (1) stability declined much faster from alcohol intoxication between 0.06% and 0.10% BAC (60-140%) compared with between 0.0% and 0.06% BAC (30%); (2) sustained exposure to repeated balance perturbations augmented the alcohol-related destabilization; (3) there were stronger effects of alcohol intoxication on stability in lateral direction than in anteroposterior direction; and (4) there was a gradual degradation of postural control particularly in lateral direction when the balance perturbations were repeated at 0.06% and 0.10% BAC, indicating adaptation deficits when intoxicated. To summarize, alcohol has profound deteriorating effects on human postural control, which are dose dependent, time dependent and direction specific. The maximal effects of alcohol intoxication on physiological performance might not be evident initially, but may be revealed first when under sustained sensory-motor challenges. Copyright © 2011 Elsevier B.V. All rights reserved.

Natural calcium isotonic composition of urine as a marker of bone mineral balance

USGS Publications Warehouse

Skulan, J.; Bullen, T.; Anbar, A.D.; Puzas, J.E.; Shackelford, L.; LeBlanc, A.; Smith, S.M.

2007-01-01

Background: We investigated whether changes in the natural isotopic composition of calcium in human urine track changes in net bone mineral balance, as predicted by a model of calcium isotopic behavior in vertebrates. If so, isotopic analysis of natural urine or blood calcium could be used to monitor short-term changes in bone mineral balance that cannot be detected with other techniques. Methods: Calcium isotopic compositions are expressed as ??44Ca, or the difference in parts per thousand between the 44Ca/40Ca of a sample and the 44Ca/ 40Ca of a standard reference material. ??44Ca was measured in urine samples from 10 persons who participated in a study of the effectiveness of countermeasures to bone loss in spaceflight, in which 17 weeks of bed rest was used to induce bone loss. Study participants were assigned to 1 of 3 treatment groups: controls received no treatment, one treatment group received alendronate, and another group performed resistive exercise. Measurements were made on urine samples collected before, at 2 or 3 points during, and after bed rest. Results: Urine ??44Ca values during bed rest were lower in controls than in individuals treated with alendronate (P <0.05, ANOVA) or exercise (P <0.05), and lower than the control group baseline (P <0.05, Mest). Results were consistent with the model and with biochemical and bone mineral density data. Conclusion: Results confirm the predicted relationship between bone mineral balance and calcium isotopes, suggesting that calcium isotopic analysis of urine might be refined into a clinical and research tool. ?? 2007 American Association for Clinical Chemistry.

Natural calcium isotopic composition of urine as a marker of bone mineral balance.

PubMed

Skulan, Joseph; Bullen, Thomas; Anbar, Ariel D; Puzas, J Edward; Shackelford, Linda; LeBlanc, Adrian; Smith, Scott M

2007-06-01

We investigated whether changes in the natural isotopic composition of calcium in human urine track changes in net bone mineral balance, as predicted by a model of calcium isotopic behavior in vertebrates. If so, isotopic analysis of natural urine or blood calcium could be used to monitor short-term changes in bone mineral balance that cannot be detected with other techniques. Calcium isotopic compositions are expressed as delta(44)Ca, or the difference in parts per thousand between the (44)Ca/(40)Ca of a sample and the (44)Ca/(40)Ca of a standard reference material. delta(44)Ca was measured in urine samples from 10 persons who participated in a study of the effectiveness of countermeasures to bone loss in spaceflight, in which 17 weeks of bed rest was used to induce bone loss. Study participants were assigned to 1 of 3 treatment groups: controls received no treatment, one treatment group received alendronate, and another group performed resistive exercise. Measurements were made on urine samples collected before, at 2 or 3 points during, and after bed rest. Urine delta(44)Ca values during bed rest were lower in controls than in individuals treated with alendronate (P <0.05, ANOVA) or exercise (P <0.05), and lower than the control group baseline (P <0.05, t-test). Results were consistent with the model and with biochemical and bone mineral density data. Results confirm the predicted relationship between bone mineral balance and calcium isotopes, suggesting that calcium isotopic analysis of urine might be refined into a clinical and research tool.

Can sensory attention focused exercise facilitate the utilization of proprioception for improved balance control in PD?

PubMed

Lefaivre, Shannon C; Almeida, Quincy J

2015-02-01

Impaired sensory processing in Parkinson's disease (PD) has been argued to contribute to balance deficits. Exercises aimed at improving sensory feedback and body awareness have the potential to ameliorate balance deficits in PD. Recently, PD SAFEx™, a sensory and attention focused rehabilitation program, has been shown to improve motor deficits in PD, although balance control has never been evaluated. The objective of this study was to measure the effects of PD SAFEx™ on balance control in PD. Twenty-one participants with mild to moderate idiopathic PD completed 12 weeks of PD SAFEx™ training (three times/week) in a group setting. Prior to training, participants completed a pre-assessment evaluating balance in accordance with an objective, computerized test of balance (modified clinical test of sensory integration and balance (m-CTSIB) and postural stability testing (PST)) protocols. The m-CTSIB was our primary outcome measure, which allowed assessment of balance in both eyes open and closed conditions, thus enabling evaluation of specific sensory contributions to balance improvement. At post-test, a significant interaction between time of assessment and vision condition (p=.014) demonstrated that all participants significantly improved balance control, specifically when eyes were closed. Balance control did not change from pre to post with eyes open. These results provide evidence that PD SAFEx™ is effective at improving the ability to utilize proprioceptive information, resulting in improved balance control in the absence of vision. Enhancing the ability to utilize proprioception for individuals with PD is an important intermediary to improving balance deficits. Copyright © 2015. Published by Elsevier B.V.

Balance, Sensorimotor, and Cognitive Performance in Long-Year Expert Senior Ballroom Dancers

PubMed Central

Kattenstroth, Jan-Christoph; Kalisch, Tobias; Kolankowska, Izabela; Dinse, Hubert R.

2011-01-01

Physical fitness is considered a major factor contributing to the maintenance of independent living and everyday competence. In line with this notion, it has been shown that several years of amateur dancing experience can exert beneficial effects not only on balance and posture but also on tactile, motor, and cognitive functions in older people. This raises the question of whether an even more extensive schedule of dancing, including competitive tournaments, would further enhance these positive effects. We therefore assessed posture, balance, and reaction times, as well as motor, tactile, and cognitive performance in older expert ballroom dancers with several years of competitive experience. We found substantially better performance in the expert group than in the controls in terms of expertise-related domains like posture, balance, and reaction times. However, there was no generalization of positive effects to those domains that were found to be improved in amateur dancers, such as tactile and cognitive performance, suggesting that there might be an optimal range of intervention intensity to maintain health and independence throughout the human lifespan. PMID:21961064

Using the systems framework for postural control to analyze the components of balance evaluated in standardized balance measures: a scoping review.

PubMed

Sibley, Kathryn M; Beauchamp, Marla K; Van Ooteghem, Karen; Straus, Sharon E; Jaglal, Susan B

2015-01-01

To identify components of postural control included in standardized balance measures for adult populations. Electronic searches of MEDLINE, EMBASE, and CINAHL databases using keyword combinations of postural balance/equilibrium, psychometrics/reproducibility of results/predictive value of tests/validation studies, instrument construction/instrument validation, geriatric assessment/disability evaluation, gray literature, and hand searches. Inclusion criteria were measures with a stated objective to assess balance, adult populations (18y and older), at least 1 psychometric evaluation, 1 standing task, a standardized protocol and evaluation criteria, and published in English. Two reviewers independently identified studies for inclusion. Sixty-six measures were included. A research assistant extracted descriptive characteristics and 2 reviewers independently coded components of balance in each measure using the Systems Framework for Postural Control, a widely recognized model of balance. Components of balance evaluated in these measures were underlying motor systems (100% of measures), anticipatory postural control (71%), dynamic stability (67%), static stability (64%), sensory integration (48%), functional stability limits (27%), reactive postural control (23%), cognitive influences (17%), and verticality (8%). Thirty-four measures evaluated 3 or fewer components of balance, and 1 measure-the Balance Evaluation Systems Test-evaluated all components of balance. Several standardized balance measures provide only partial information on postural control and omit important components of balance related to avoiding falls. As such, the choice of measure(s) may limit the overall interpretation of an individual's balance ability. Continued work is necessary to increase the implementation of comprehensive balance assessment in research and practice. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A Simplified Model of Human Alcohol Metabolism That Integrates Biotechnology and Human Health into a Mass Balance Team Project

ERIC Educational Resources Information Center

Yang, Allen H. J.; Dimiduk, Kathryn; Daniel, Susan

2011-01-01

We present a simplified human alcohol metabolism model for a mass balance team project. Students explore aspects of engineering in biotechnology: designing/modeling biological systems, testing the design/model, evaluating new conditions, and exploring cutting-edge "lab-on-a-chip" research. This project highlights chemical engineering's impact on…

Self-reported balance status is not a reliable indicator of balance performance in adolescents at one-month post-concussion.

PubMed

Rochefort, Coralie; Walters-Stewart, Coren; Aglipay, Mary; Barrowman, Nick; Zemek, Roger; Sveistrup, Heidi

2017-11-01

To determine if self-reported balance symptoms can be used as a proxy for measures of the center of pressure (COP) to identify balance deficits in a group of concussed adolescents. Case-control. Thirteen adolescents 1-month post-concussion who reported ongoing balance problems (Balance+), 20 adolescent 1-month post-concussion who reported no balance problems (Balance-), and 30 non-injured adolescents (control) completed a series of balance tests. Participants completed two 2-min trials standing on a Nintendo Wii Balance Board™ during which the COP under their feet was recorded: i) double-leg stance, eyes open; ii) double-leg stance, eyes closed. Participants also completed a dual-task condition combining a double-leg stance and a Stroop Colour-word test. Participants in both the Balance+ and Balance- group swayed over a larger ellipse area compared to the control group while completing the Eyes Closed (Balance+, p=0.002; Balance-, p=0.002) and Dual-Task (Balance+, p=0.001; Balance-, p=0.004) conditions and performed the Dual-Task condition with faster medio-lateral velocity (Balance+, p=0.003; Balance-, p=0.009). The participants in the Balance- group also swayed over a larger ellipse area compared to the control group while completing the Eyes Open condition (p=0.005). No significant differences were identified between the Balance+ and Balance- groups. At 1-month post-concussion, adolescents demonstrated balance deficits compared to non-injured adolescents regardless of whether they reported balance problems. These results suggest that self-reported balance status might not be an accurate reflection of balance performance following a concussion in adolescents. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

The Role of Serotonin (5-HT) in Behavioral Control: Findings from Animal Research and Clinical Implications

PubMed Central

Sanchez, CL; Biskup, CS; Herpertz, S; Gaber, TJ; Kuhn, CM; Hood, SH

2015-01-01

The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. PMID:25991656

Comparison between Decision Tree and Genetic Programming to distinguish healthy from stroke postural sway patterns.

PubMed

Marrega, Luiz H G; Silva, Simone M; Manffra, Elisangela F; Nievola, Julio C

2015-01-01

Maintaining balance is a motor task of crucial importance for humans to perform their daily activities safely and independently. Studies in the field of Artificial Intelligence have considered different classification methods in order to distinguish healthy subjects from patients with certain motor disorders based on their postural strategies during the balance control. The main purpose of this paper is to compare the performance between Decision Tree (DT) and Genetic Programming (GP) - both classification methods of easy interpretation by health professionals - to distinguish postural sway patterns produced by healthy and stroke individuals based on 16 widely used posturographic variables. For this purpose, we used a posturographic dataset of time-series of center-of-pressure displacements derived from 19 stroke patients and 19 healthy matched subjects in three quiet standing tasks of balance control. Then, DT and GP models were trained and tested under two different experiments where accuracy, sensitivity and specificity were adopted as performance metrics. The DT method has performed statistically significant (P < 0.05) better in both cases, showing for example an accuracy of 72.8% against 69.2% from GP in the second experiment of this paper.

Footwear effects on walking balance at elevation.

PubMed

Simeonov, Peter; Hsiao, Hongwei; Powers, John; Ammons, Douglas; Amendola, Alfred; Kau, Tsui-Ying; Cantis, Douglas

2008-12-01

The study evaluated the effects of shoe style on workers' instability during walking at elevation. Twenty-four construction workers performed walking tasks on roof planks in a surround-screen virtual reality system, which simulated a residential roof environment. Three common athletic and three work shoe styles were tested on wide, narrow and tilted planks on a simulated roof and on an unrestricted surface at simulated ground. Dependent variables included lateral angular velocities of the trunk and the rear foot, as well as the workers' rated perceptions of instability. The results demonstrated that shoe style significantly affected workers walking instability at elevated work environments. The results highlighted two major shoe-design pathways for improving walking balance at elevation: enhancing rear foot motion control; and improving ankle proprioception. This study also outlined some of the challenges in optimal shoe selection and specific shoe-design needs for improved walking stability during roof work. The study adds to the knowledge in the area of balance control, by emphasising the role of footwear as a critical human-support surface interface during work on narrow surfaces at height. The results can be used for footwear selection and improvements to reduce risk of falls from elevation.

Postural control and balance self-efficacy in women with fibromyalgia: are there differences?

PubMed

Muto, L H A; Sauer, J F; Yuan, S L K; Sousa, A; Mango, P C; Marques, A P

2015-04-01

Fibromyalgia (FM) is a rheumatic disease characterized by chronic widespread pain and symptoms such as fatigue, sleep disturbances, cognitive difficulties, and depression. Postural instability is a debilitating disorder increasingly recognized as part of FM. To assess and compare postural control and balance self-efficacy in women with and without FM and verify the association of these variables with pain, symptom severity, and strength. Case-control study Physiotherapeutic Clinical Research and Electromyography Laboratory Department of Physical Therapy, Speech Therapy, and Occupational Therapy, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil. Case-control study of 117 women ranging from age 35 to 60 years. Of these, 67 had FM. Posture control was assessed with the modified clinical test of sensory interaction on balance with patients in forceplates, balance self-efficacy with the Activities-specific Balance Confidence Scale, pain severity with the Visual Analog Scale, tender point pain threshold with digital algometry, symptom severity with the fibromyalgia impact questionnaire, and lower limb strength with a dynamometer. Individuals with FM had impaired postural control showing increased speed of oscillation of the center of gravity (P=0.004) and decreased balance self-efficacy (P<0.001). They had moderate to excellent correlations of balance self-efficacy with pain (r=0.7, P<0.01), muscle strength (r=0.52, P<0.01), and symptom severity (r=0.78, P<0.10) compared with the control group. Correlation of postural control with the same variables was weak. Patients with FM have impaired postural control and low balance self-efficacy that are associated with pain, muscle strength, and symptom severity. Postural control and balance self-efficacy needs to be assessed in patients with FM and the treatment goals should be the improvement of postural control and balance self-efficacy.

Relationship between antigravity control and postural control in young children.

PubMed

Sellers, J S

1988-04-01

The purposes of this study were 1) to determine the relationship between antigravity control (supine flexion and prone extension) and postural control (static and dynamic balance), 2) to determine the quality of antigravity and postural control, and 3) to determine whether sex and ethnic group differences correlate with differences in antigravity control and postural control in young children. I tested 107 black, Hispanic, and Caucasian children in a Head Start program, with a mean age of 61 months. The study results showed significant relationships between antigravity control and postural control. Subjects' supine flexion performance was significantly related to the quantity and quality of their static and dynamic balance performance, whereas prone extension performance was related only to the quality of dynamic balance performance. Quality scale measurements (r = .90) indicated that the children in this study had not yet developed full antigravity or postural control. The study results revealed differences between sexes in the quality of static balance and prone extension performance and ethnic differences in static balance, dynamic balance, and prone extension performance.

Proteolysis inhibition by hibernating bear serum leads to increased protein content in human muscle cells.

PubMed

Chanon, Stéphanie; Chazarin, Blandine; Toubhans, Benoit; Durand, Christine; Chery, Isabelle; Robert, Maud; Vieille-Marchiset, Aurélie; Swenson, Jon E; Zedrosser, Andreas; Evans, Alina L; Brunberg, Sven; Arnemo, Jon M; Gauquelin-Koch, Guillemette; Storey, Kenneth B; Simon, Chantal; Blanc, Stéphane; Bertile, Fabrice; Lefai, Etienne

2018-04-03

Muscle atrophy is one of the main characteristics of human ageing and physical inactivity, with resulting adverse health outcomes. To date, there are still no efficient therapeutic strategies for its prevention and/or treatment. However, during hibernation, bears exhibit a unique ability for preserving muscle in conditions where muscle atrophy would be expected in humans. Therefore, our objective was to determine whether there are components of bear serum which can control protein balance in human muscles. In this study, we exposed cultured human differentiated muscle cells to bear serum collected during winter and summer periods, and measured the impact on cell protein content and turnover. In addition, we explored the signalling pathways that control rates of protein synthesis and degradation. We show that the protein turnover of human myotubes is reduced when incubated with winter bear serum, with a dramatic inhibition of proteolysis involving both proteasomal and lysosomal systems, and resulting in an increase in muscle cell protein content. By modulating intracellular signalling pathways and inducing a protein sparing phenotype in human muscle cells, winter bear serum therefore holds potential for developing new tools to fight human muscle atrophy and related metabolic disorders.

Manually controlled human balancing using visual, vestibular and proprioceptive senses involves a common, low frequency neural process

PubMed Central

Lakie, Martin; Loram, Ian D

2006-01-01

Ten subjects balanced their own body or a mechanically equivalent unstable inverted pendulum by hand, through a compliant spring linkage. Their balancing process was always characterized by repeated small reciprocating hand movements. These bias adjustments were an observable sign of intermittent alterations in neural output. On average, the adjustments occurred at intervals of ∼400 ms. To generate appropriate stabilizing bias adjustments, sensory information about body or load movement is needed. Subjects used visual, vestibular or proprioceptive sensation alone and in combination to perform the tasks. We first ask, is the time between adjustments (bias duration) sensory specific? Vision is associated with slow responses. Other senses involved with balance are known to be faster. Our second question is; does bias duration depend on sensory abundance? An appropriate bias adjustment cannot occur until unplanned motion is unambiguously perceived (a sensory threshold). The addition of more sensory data should therefore expedite action, decreasing the mean bias adjustment duration. Statistical analysis showed that (1) the mean bias adjustment duration was remarkably independent of the sensory modality and (2) the addition of one or two sensory modalities made a small, but significant, decrease in the mean bias adjustment duration. Thus, a threshold effect can alter only a very minor part of the bias duration. The bias adjustment duration in manual balancing must reflect something more than visual sensation and perceptual thresholds; our suggestion is that it is a common central motor planning process. We predict that similar processes may be identified in the control of standing. PMID:16959857

Bath Breakfast Project (BBP) - Examining the role of extended daily fasting in human energy balance and associated health outcomes: Study protocol for a randomised controlled trial [ISRCTN31521726

PubMed Central

2011-01-01

Background Current guidance regarding the role of daily breakfast in human health is largely grounded in cross-sectional observations. However, the causal nature of these relationships has not been fully explored and what limited information is emerging from controlled laboratory-based experiments appears inconsistent with much existing data. Further progress in our understanding therefore requires a direct examination of how daily breakfast impacts human health under free-living conditions. Methods/Design The Bath Breakfast Project (BBP) is a randomised controlled trial comparing the effects of daily breakfast consumption relative to extended fasting on energy balance and human health. Approximately 70 men and women will undergo extensive laboratory-based assessments of their acute metabolic responses under fasted and post-prandial conditions, to include: resting metabolic rate, substrate oxidation, dietary-induced thermogenesis and systemic concentrations of key metabolites/hormones. Physiological and psychological indices of appetite will also be monitored both over the first few hours of the day (i.e. whether fed or fasted) and also following a standardised test lunch used to assess voluntary energy intake under controlled conditions. Baseline measurements of participants' anthropometric characteristics (e.g. DEXA) will be recorded prior to intervention, along with an oral glucose tolerance test and acquisition of adipose tissue samples to determine expression of key genes and estimates of tissue-specific insulin action. Participants will then be randomly assigned either to a group prescribed an energy intake of ≥3000 kJ before 1100 each day or a group to extend their overnight fast by abstaining from ingestion of energy-providing nutrients until 1200 each day, with all laboratory-based measurements followed-up 6 weeks later. Free-living assessments of energy intake (via direct weighed food diaries) and energy expenditure (via combined heart-rate/accelerometry) will be made during the first and last week of intervention, with continuous glucose monitors worn both to document chronic glycaemic responses to the intervention and to verify compliance. Trial registration Current Controlled Trials ISRCTN31521726. PMID:21740575

Modelling of human-machine interaction in equipment design of manufacturing cells

NASA Astrophysics Data System (ADS)

Cochran, David S.; Arinez, Jorge F.; Collins, Micah T.; Bi, Zhuming

2017-08-01

This paper proposes a systematic approach to model human-machine interactions (HMIs) in supervisory control of machining operations; it characterises the coexistence of machines and humans for an enterprise to balance the goals of automation/productivity and flexibility/agility. In the proposed HMI model, an operator is associated with a set of behavioural roles as a supervisor for multiple, semi-automated manufacturing processes. The model is innovative in the sense that (1) it represents an HMI based on its functions for process control but provides the flexibility for ongoing improvements in the execution of manufacturing processes; (2) it provides a computational tool to define functional requirements for an operator in HMIs. The proposed model can be used to design production systems at different levels of an enterprise architecture, particularly at the machine level in a production system where operators interact with semi-automation to accomplish the goal of 'autonomation' - automation that augments the capabilities of human beings.

The Effects of Pilates Training on Balance Control and Self-Reported Health Status in Community-Dwelling Older Adults: A Randomized Controlled Trial.

PubMed

Gabizon, Hadas; Press, Yan; Volkov, Ilia; Melzer, Itshak

2016-07-01

To evaluate the effect of a group-based Pilates training program on balance control and health status in healthy older adults. A single-blind, randomized, controlled trial. General community. A total of 88 community-dwelling older adults (age 71.15 ± 4.30 years), without evidence of functional balance impairment, were recruited and allocated at random to a Pilates intervention group (n = 44) or a control group (n = 44). The Pilates intervention group received 36 training sessions over three months (3 sessions a week), while the control group did not receive any intervention. Standing upright postural stability, performance-based measures of balance, and self-reported health status was assessed in both groups at baseline and at the end of the intervention period. Compared with the control group, the Pilates intervention did not improve postural stability, baseline functional measures of balance, or health status. The results suggest that because Pilates training is not task specific, it does not improve balance control or balance function in independent older adults.

The effect of general and spinal anesthesia on balance control in elderly patients.

PubMed

Suárez, Alejo; Macadar, Omar

2008-01-01

Falls are a major problem in the elderly population, but few communications address the influence of anesthesia on balance control. This study reports how a general balanced anesthesia (GBA) and a spinal anesthesia (SA) affect balance control in the elderly. We divided into three groups, according to electronystagmography findings and type of anesthesia, 21 men older than 65 years (mean age, 72 years) who were scheduled for prostate adenectomy. One group, designated GBN, consisted of normal subjects who underwent surgery under GBA. In another group, designated GBP, were pathological subjects who had clinically compensated central vestibular disorders (CVDs) and underwent surgery under GBA. The third group, designated SP, contained CVD patients who underwent surgery under SA. We assessed balance control via static posturography preoperatively and 48 hours postoperatively. We observed no change in balance control parameters (center of pressure distribution area [COPa] or COP sway velocity [SV]) for those patients in the GBN group or for those in the SP group. We did observe a significant difference for the patients in the GBP group, with higher postoperative values of COPa and SV (Wilcoxon signed rank test). Our results showed that in subjects with clinically compensated underlying CVD prior to a GBA, balance control worsens after the procedure, whereas no change in balance control occurs after an SA. Balance control in subjects with normal vestibuloocular function did not change even after a GBA.

Effects of m-xylene on human equilibrium measured with a quantitative method.

PubMed

Savolainen, K; Linnavuo, M

1979-04-01

Swaying during normal upright posture in 17 young males and the effects of m-xylene exposure on the body sway of six of the 17 has been studied by a quantitative Romberg test, conducted with an equipment consisting of a strain gauge transducer platform and of an electronic unit. The exposures were conducted in a dynamic exposure chamber. The sway of the 17 subjects was larger when their eyes were closed than when they were open (P less than 0.001) indicating the importance of vision in the control of body balance. Exposure to a time-weighted average (TWA) concentration of 100 p.p.m. (4.1 mumol/l) of xylene with 200 p.p.m. (8.2 mumol/l) peaks had no observable effect on the body balance of the six subjects. Exposure to a TWA concentration of 200 p.p.m. of xylene with 400 p.p.m. (16.4 mumol/l) peaks--the corresponding mean concentration of xylene in venous blood being 29.1 +/- 3.2 mumol/l--clearly impaired the body balance of the six subjects. The impairment was most pronounced with the eyes closed (P = 0.016). The results suggest that human equilibrium is rather sensitive to effects of exposure to xylene.

Symmetry in running.

PubMed

Raibert, M H

1986-03-14

Symmetry plays a key role in simplifying the control of legged robots and in giving them the ability to run and balance. The symmetries studied describe motion of the body and legs in terms of even and odd functions of time. A legged system running with these symmetries travels with a fixed forward speed and a stable upright posture. The symmetries used for controlling legged robots may help in elucidating the legged behavior of animals. Measurements of running in the cat and human show that the feet and body sometimes move as predicted by the even and odd symmetry functions.

Advances in natural stable isotope ratio analysis of human hair to determine nutritional and metabolic status.

PubMed

Petzke, Klaus J; Fuller, Benjamin T; Metges, Cornelia C

2010-09-01

We review the literature on the use of stable isotope ratios at natural abundance to reveal information about dietary habits and specific nutrient intakes in human hair protein (keratin) and amino acids. In particular, we examine whether hair isotopic compositions can be used as unbiased biomarkers to provide information about nutritional status, metabolism, and diseases. Although the majority of research on the stable isotope ratio analysis of hair has focused on bulk protein, methods have been recently employed to examine amino acid-specific isotope ratios using gas chromatography or liquid chromatography coupled to an isotope ratio mass spectrometer. The isotopic measurement of amino acids has the potential to answer research questions on amino acid nutrition, metabolism, and disease processes and can contribute to a better understanding of the variations in bulk protein isotope ratio values. First results suggest that stable isotope ratios are promising as unbiased nutritional biomarkers in epidemiological research. However, variations in stable isotope ratios of human hair are also influenced by nutrition-dependent nitrogen balance, and more controlled clinical research is needed to examine these effects in human hair. Stable isotope ratio analysis at natural abundance in human hair protein offers a noninvasive method to reveal information about long-term nutritional exposure to specific nutrients, nutritional habits, and in the diagnostics of diseases leading to nutritional stress and impaired nitrogen balance.

[Neuronal control of posture and locomotion in decerebrated and spinalized animals].

PubMed

Musienko, P E; Gorskiĭ, O V; Kilimnik, V A; Kozlovskaia, I B; Courtine, G; Edgerton, V R; Gerasimenko, Iu P

2013-03-01

We have found that the brainstem-spinal cord circuitry of decerebrated cats actively maintain the equilibrium during standing, walking and imposed mechanical perturbations similar to that observed in intact animals. The corrective hindlimb motor responses during standing included redistribution of the extensor activity ipsilateral and contralateral to perturbation. The postural corrections in walking cats were due to considerable modification of EMG pattern in the limbs as well as changing of the swing-stance phases of the step cycle and ground reaction forces depending of perturbation side. Thus the basic mechanisms for balance control of decerebrated animals in these two forms of motor behavior are different. Balance-related adjustments relied entirely on the integration of somatosensory information arising from the moving hindquarters because of the suppression of vestibular, visual, and head-neck-trunk sensory input. We propose that the somatosensory input from the hindquarters in concert with the lumbosacral spinal circuitry can control the dynamics of the hindquarters sufficient to sustain balance. We found that, after isolation from the brainstem or forebrain, lumbosacral circuits receiving tonic epidural electrical stimulation can effectively control equilibrium during standing and stepping. Detailed analyses of the relationships among muscle activity, trunk kinematics, and limb kinetics indicate that spinal motor systems utilize a combination of feedback and feedforward strategies to maintain dynamic equilibrium during walking. The unexpected ability of spinal circuitries to exert efficient postural control in the presence of epidural electrical stimulation in decerebrated and spinal cats have significant implications for the potential of humans with a severe spinal cord injury to regain a significant level of functional standing and walking capacities.

Dynamic Balance of Excitation and Inhibition in Human and Monkey Neocortex

NASA Astrophysics Data System (ADS)

Dehghani, Nima; Peyrache, Adrien; Telenczuk, Bartosz; Le van Quyen, Michel; Halgren, Eric; Cash, Sydney S.; Hatsopoulos, Nicholas G.; Destexhe, Alain

2016-03-01

Balance of excitation and inhibition is a fundamental feature of in vivo network activity and is important for its computations. However, its presence in the neocortex of higher mammals is not well established. We investigated the dynamics of excitation and inhibition using dense multielectrode recordings in humans and monkeys. We found that in all states of the wake-sleep cycle, excitatory and inhibitory ensembles are well balanced, and co-fluctuate with slight instantaneous deviations from perfect balance, mostly in slow-wave sleep. Remarkably, these correlated fluctuations are seen for many different temporal scales. The similarity of these computational features with a network model of self-generated balanced states suggests that such balanced activity is essentially generated by recurrent activity in the local network and is not due to external inputs. Finally, we find that this balance breaks down during seizures, where the temporal correlation of excitatory and inhibitory populations is disrupted. These results show that balanced activity is a feature of normal brain activity, and break down of the balance could be an important factor to define pathological states.

Robotic investigation on effect of stretch reflex and crossed inhibitory response on bipedal hopping

PubMed Central

Rosendo, Andre; Ikemoto, Shuhei; Shimizu, Masahiro; Hosoda, Koh

2018-01-01

To maintain balance during dynamic locomotion, the effects of proprioceptive sensory feedback control (e.g. reflexive control) should not be ignored because of its simple sensation and fast reaction time. Scientists have identified the pathways of reflexes; however, it is difficult to investigate their effects during locomotion because locomotion is controlled by a complex neural system and current technology does not allow us to change the control pathways in living humans. To understand these effects, we construct a musculoskeletal bipedal robot, which has similar body structure and dynamics to those of a human. By conducting experiments on this robot, we investigate the effects of reflexes (stretch reflex and crossed inhibitory response) on posture during hopping, a simple and representative bouncing gait with complex dynamics. Through over 300 hopping trials, we confirm that both the stretch reflex and crossed response can contribute to reducing the lateral inclination during hopping. These reflexive pathways do not use any prior knowledge of the dynamic information of the body such as its inclination. Beyond improving the understanding of the human neural system, this study provides roboticists with biomimetic ideas for robot locomotion control. PMID:29593088

Muscle Contributions to Frontal Plane Angular Momentum during Walking

PubMed Central

Neptune, Richard R.; McGowan, Craig P.

2016-01-01

The regulation of whole-body angular momentum is important for maintaining dynamic balance during human walking, which is particularly challenging in the frontal plane. Whole-body angular momentum is actively regulated by individual muscle forces. Thus, understanding which muscles contribute to frontal plane angular momentum will further our understanding of mediolateral balance control and has the potential to help diagnose and treat balance disorders. The purpose of this study was to identify how individual muscles and gravity contribute to whole-body angular momentum in the frontal plane using a muscle-actuated forward dynamics simulation analysis. A three-dimensional simulation was developed that emulated the average walking mechanics of a group of young healthy adults (n=10). The results showed that a finite set of muscles are the primary contributors to frontal plane balance and that these contributions vary throughout the gait cycle. In early stance, the vasti, adductor magnus and gravity acted to rotate the body towards the contralateral leg while the gluteus medius acted to rotate the body towards the ipsilateral leg. In late stance, the gluteus medius continued to rotate the body towards the ipsilateral leg while the soleus and gastrocnemius acted to rotate the body towards the contralateral leg. These results highlight those muscles that are critical to maintaining dynamic balance in the frontal plane during walking and may provide targets for locomotor therapies aimed at treating balance disorders. PMID:27522538

The Multivariate Largest Lyapunov Exponent as an Age-Related Metric of Quiet Standing Balance

PubMed Central

Liu, Kun; Wang, Hongrui; Xiao, Jinzhuang

2015-01-01

The largest Lyapunov exponent has been researched as a metric of the balance ability during human quiet standing. However, the sensitivity and accuracy of this measurement method are not good enough for clinical use. The present research proposes a metric of the human body's standing balance ability based on the multivariate largest Lyapunov exponent which can quantify the human standing balance. The dynamic multivariate time series of ankle, knee, and hip were measured by multiple electrical goniometers. Thirty-six normal people of different ages participated in the test. With acquired data, the multivariate largest Lyapunov exponent was calculated. Finally, the results of the proposed approach were analysed and compared with the traditional method, for which the largest Lyapunov exponent and power spectral density from the centre of pressure were also calculated. The following conclusions can be obtained. The multivariate largest Lyapunov exponent has a higher degree of differentiation in differentiating balance in eyes-closed conditions. The MLLE value reflects the overall coordination between multisegment movements. Individuals of different ages can be distinguished by their MLLE values. The standing stability of human is reduced with the increment of age. PMID:26064182

Contributions to lateral balance control in ambulatory older adults.

PubMed

Sparto, Patrick J; Newman, A B; Simonsick, E M; Caserotti, P; Strotmeyer, E S; Kritchevsky, S B; Yaffe, K; Rosano, C

2018-06-01

In older adults, impaired control of standing balance in the lateral direction is associated with the increased risk of falling. Assessing the factors that contribute to impaired standing balance control may identify areas to address to reduce falls risk. To investigate the contributions of physiological factors to standing lateral balance control. Two hundred twenty-two participants from the Pittsburgh site of the Health, Aging and Body Composition Study had lateral balance control assessed using a clinical sensory integration balance test (standing on level and foam surface with eyes open and closed) and a lateral center of pressure tracking test using visual feedback. The center of pressure was recorded from a force platform. Multiple linear regression models examined contributors of lateral control of balance performance, including concurrently measured tests of lower extremity sensation, knee extensor strength, executive function, and clinical balance tests. Models were adjusted for age, body mass index, and sex. Larger lateral sway during the sensory integration test performed on foam was associated with longer repeated chair stands time. During the lateral center of pressure tracking task, the error in tracking increased at higher frequencies; greater error was associated with worse executive function. The relationship between sway performance and physical and cognitive function differed between women and men. Contributors to control of lateral balance were task-dependent. Lateral standing performance on an unstable surface may be more dependent upon general lower extremity strength, whereas visual tracking performance may be more dependent upon cognitive factors. Lateral balance control in ambulatory older adults is associated with deficits in strength and executive function.

Virtual reality applications in improving postural control and minimizing falls.

PubMed

Virk, Sumandeep; McConville, Kristiina M Valter

2006-01-01

Maintaining balance under all conditions is an absolute requirement for humans. Orientation in space and balance maintenance requires inputs from the vestibular, the visual, the proprioceptive and the somatosensory systems. All the cues coming from these systems are integrated by the central nervous system (CNS) to employ different strategies for orientation and balance. How the CNS integrates all the inputs and makes cognitive decisions about balance strategies has been an area of interest for biomedical engineers for a long time. More interesting is the fact that in the absence of one or more cues, or when the input from one of the sensors is skewed, the CNS "adapts" to the new environment and gives less weight to the conflicting inputs [1]. The focus of this paper is a review of different strategies and models put forward by researchers to explain the integration of these sensory cues. Also, the paper compares the different approaches used by young and old adults in maintaining balance. Since with age the musculoskeletal, visual and vestibular system deteriorates, the older subjects have to compensate for these impaired sensory cues for postural stability. The paper also discusses the applications of virtual reality in rehabilitation programs not only for balance in the elderly but also in occupational falls. Virtual reality has profound applications in the field of balance rehabilitation and training because of its relatively low cost. Studies will be conducted to evaluate the effectiveness of virtual reality training in modifying the head and eye movement strategies, and determine the role of these responses in the maintenance of balance.

Balance treatment ameliorates anxiety and increases self-esteem in children with comorbid anxiety and balance disorder.

PubMed

Bart, Orit; Bar-Haim, Yair; Weizman, Einat; Levin, Moran; Sadeh, Avi; Mintz, Matti

2009-01-01

Comorbidity between balance and anxiety disorders in adult population is a well-studied clinical entity. Children might be particularly prone to develop balance-anxiety comorbidity, but surprisingly they are practically neglected in this field of research. The consequence is that children are treated for what seems to be the primary disorder without noticing possible effects on the other disorder. In Study 1, children with balance dysfunction were compared to normally balanced controls on anxiety and self-esteem. In study 2, children with balance dysfunction were assigned to either balance training or a waiting-list control. Training consisted of 12 weekly sessions of balance treatment. Anxiety and self-esteem were tested before and after treatment/waiting. Study 1 confirmed significantly higher anxiety and lower self-esteem in the balance dysfunction group compared to the control group. Study 2 showed that treatment improved balance performance, reduced anxiety, and increased self-esteem relative to the control waiting list group. Taken together, the present findings are in accord with the observations of comorbidity between balance and anxiety disorders in adults and confirm their validity in children younger than 7 years of age. This profile of comorbidity between balance dysfunction and anxiety also include lower self-esteem.

Integrity management of offshore structures and its implication on computation of structural action effects and resistance

NASA Astrophysics Data System (ADS)

Moan, T.

2017-12-01

An overview of integrity management of offshore structures, with emphasis on the oil and gas energy sector, is given. Based on relevant accident experiences and means to control the associated risks, accidents are categorized from a technical-physical as well as human and organizational point of view. Structural risk relates to extreme actions as well as structural degradation. Risk mitigation measures, including adequate design criteria, inspection, repair and maintenance as well as quality assurance and control of engineering processes, are briefly outlined. The current status of risk and reliability methodology to aid decisions in the integrity management is briefly reviewed. Finally, the need to balance the uncertainties in data, methods and computational efforts and the cautious use and quality assurance and control in applying high fidelity methods to avoid human errors, is emphasized, and with a plea to develop both high fidelity as well as efficient, simplified methods for design.

The relationship between balance confidence and control in individuals with Parkinson's disease

PubMed Central

Lee, Hyo Keun; Altman, Lori J.P.; McFarland, Nikolaus; Hass, Chris J.

2016-01-01

Introduction A broad range of subjective and objective assessments have been used to assess balance confidence and balance control in persons with Parkinson's disease (PD). However, little is known about the relationship between self-perceived balance confidence and actual balance control in PD. The purpose of this investigation was to determine the relationship between self-perceived balance confidence and objectively measured static/dynamic balance control abilities. Methods Forty-four individuals with PD participated in the study. Patients were stratified into 2 groups based on the modified Hoehn and Yahr (H&Y) disability score: early stage, H&Y≤2.0 and moderate stage, H&Y ≥2.5. All participants completed the activities-specific balance confidence (ABC) scale and performed standing balance and gait initiation tasks to assess static and dynamic balance control. The center of pressure (COP) sway (CE95%Sway) during static balance and the peak distance between the projections of the COP and the center of mass (COM) in the transverse plane (COPCOM) during gait initiation were calculated. Pearson correlation analyses were conducted relating the ABC score and CE95%Sway and COPCOM. Results For early stage PD, there was a moderate correlation between ABC score and CE95 %Sway (r=-0.56, R2=0.32, p=0.002), while no significant correlation was found between ABC score and COPCOM (r=-0.24, R2=0.06, p=0.227). For moderate stage PD, there was a moderate correlation between ABC score and COPCOM (r=0.49, R2=0.24, p=0.044), while no correlation was found between ABC score and CE95%Sway (r=-0.19, R2=0.04, p=0.478). Conclusion Individuals with different disease severities showed different relationships between balance confidence and actual static/dynamic balance control. PMID:26949065

Effectiveness of balance training programme in reducing the frequency of falling in established osteoporotic women: a randomized controlled trial.

PubMed

Mikó, Ibolya; Szerb, Imre; Szerb, Anna; Poor, Gyula

2017-02-01

To investigate the effect of a 12-month sensomotor balance exercise programme on postural control and the frequency of falling in women with established osteoporosis. Randomized controlled trial where the intervention group was assigned the 12-month Balance Training Programme and the control group did not undertake any intervention beyond regular osteoporosis treatment. A total of 100 osteoporotic women - at least with one osteoporotic fracture - aged 65 years old and above. Balance was assessed in static and dynamic posture both with performance-based measures of balance, such as the Berg Balance Scale and the Timed Up and Go Test, and with a stabilometric computerized platform. Patients in the intervention group completed the 12-month sensomotor Balance Training Programme in an outpatient setting, guided by physical therapists, three times a week, for 30 minutes. The Berg Balance Scale and the Timed Up and Go Test showed a statistically significant improvement of balance in the intervention group ( p = 0.001 and p = 0.005, respectively). Balance tests using the stabilometer also showed a statistically significant improvement in static and dynamic postural balance for osteoporotic women after the completion of the Balance Training Programme. As a consequence, the one-year exercise programme significantly decreased the number of falls in the exercise group compared with the control group. The Balance Training Programme significantly improved the balance parameters and reduced the number of falls in postmenopausal women who have already had at least one fracture in the past.

Improving Balance in Subacute Stroke Patients: A Randomized Controlled Study

ERIC Educational Resources Information Center

Goljar, Nika; Burger, Helena; Rudolf, Marko; Stanonik, Irena

2010-01-01

The aim of the study was to compare the efficacy of balance training in a balance trainer, a newly developed mechanical device for training balance, with conventional balance training in subacute stroke patients. This was a randomized controlled study. Fifty participants met the inclusion criteria and 39 finished the study. The participants were…

Reducing fall risk by improving balance control: development, evaluation and knowledge-translation of new approaches.

PubMed

Maki, Brian E; Sibley, Katherine M; Jaglal, Susan B; Bayley, Mark; Brooks, Dina; Fernie, Geoff R; Flint, Alastair J; Gage, William; Liu, Barbara A; McIlroy, William E; Mihailidis, Alex; Perry, Stephen D; Popovic, Milos R; Pratt, Jay; Zettel, John L

2011-12-01

Falling is a leading cause of serious injury, loss of independence, and nursing-home admission in older adults. Impaired balance control is a major contributing factor. Results from our balance-control studies have been applied in the development of new and improved interventions and assessment tools. Initiatives to facilitate knowledge-translation of this work include setting up a new network of balance clinics, a research-user network and a research-user advisory board. Our findings support the efficacy of the developed balance-training methods, balance-enhancing footwear, neuro-prosthesis, walker design, handrail-cueing system, and handrail-design recommendations in improving specific aspects of balance control. IMPACT ON KNOWLEDGE USERS: A new balance-assessment tool has been implemented in the first new balance clinic, a new balance-enhancing insole is available through pharmacies and other commercial outlets, and handrail design recommendations have been incorporated into 10 Canadian and American building codes. Work in progress is expected to have further impact. Copyright © 2011 National Safety Council and Elsevier Ltd. All rights reserved.

Chemotherapy Necessitates Increased Immune Control of HHVs: A Cause of Persistent Inflammation Enabling Protracted Fatigue in Breast Cancer Survivors

DTIC Science & Technology

2014-10-01

14. ABSTRACT This work hypothesizes that chemotherapy can permanently alter the balance between the immune system and chronic herpes virus...infections. We predicted that herpes virus-driven inflammatory cytokines exacerbate cancer treatment related fatigue (CTRF). Here we report the significant...TERMS breast cancer, chemotherapy, immunology, human herpes viruses, survivor fatigue 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT

Metabolic alkalosis, bedside and bench.

PubMed

Laski, Melvin E; Sabatini, Sandra

2006-11-01

Although significant contributions to the understanding of metabolic alkalosis have been made recently, much of our knowledge rests on data from clearance studies performed in humans and animals many years ago. This article reviews the contributions of these studies, as well as more recent work relating to the control of renal acid-base transport by mineralocorticoid hormones, angiotensin, endothelin, nitric oxide, and potassium balance. Finally, clinical aspects of metabolic alkalosis are considered.

Impact of yogurt on appetite control, energy balance, and body composition.

PubMed

Tremblay, Angelo; Doyon, Caroline; Sanchez, Marina

2015-08-01

Recent data support the idea that regular yogurt consumption promotes body weight stability. The simplest explanation is that regular consumption of healthful foods such as yogurt results in decreased intake of less healthful foods containing high amounts of fat and/or sugar. There is also evidence to suggest that the high calcium and protein contents of yogurt and other dairy foods influence appetite and energy intake. The existence of a calcium-specific appetite control mechanism has been proposed. Milk proteins differ in terms of absorption rate and post-absorptive responses, which can influence their satiating properties. Studies in humans have shown that consumption of milk and yogurt increases the circulating concentration of the anorectic peptides glucagon-like peptide (GLP)-1 and peptide YY (PYY). The food matrix can also affect appetite and satiety. Yogurt is a fermented milk that contains bacteria that enrich the microbiota of the host. It appears that lean vs obese humans differ in the composition of their gut microbiota. The available relevant literature suggests that yogurt is a food that facilitates the regulation of energy balance. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Effect of balance training on postural balance control and risk of fall in children with diplegic cerebral palsy.

PubMed

El-Shamy, Shamekh Mohamed; Abd El Kafy, Ehab Mohamed

2014-01-01

The purpose of this study was to evaluate the effects of balance training on postural control and fall risk in children with diplegic cerebral palsy. Thirty spastic diplegic cerebral palsied children (10-12 years) were included in this study. Children were randomly assigned into two equal-sized groups: control and study groups. Participants in both groups received a traditional physical therapy exercise program. The study group additionally received balance training on the Biodex balance system. Treatment was provided 30 min/d, 3 d/week for 3 successive months. To evaluate the limit of stability and fall risk, participated children received baseline and post-treatment assessments using the Biodex balance system. Overall directional control, total time to complete the test, overall stability index of the fall risk test and total score of the pediatric balance scale were measured. Children in both groups showed significant improvements in the mean values of all measured variables post-treatment (p < 0.05). The results also showed significantly better improvement in the measured parameters for the study group, as compared to the control group (p < 0.05). Balance training on Biodex system is a useful tool that can be used in improving postural balance control in children with diplegic cerebral palsy.

Ventral striatal dopamine reflects behavioral and neural signatures of model-based control during sequential decision making.

PubMed

Deserno, Lorenz; Huys, Quentin J M; Boehme, Rebecca; Buchert, Ralph; Heinze, Hans-Jochen; Grace, Anthony A; Dolan, Raymond J; Heinz, Andreas; Schlagenhauf, Florian

2015-02-03

Dual system theories suggest that behavioral control is parsed between a deliberative "model-based" and a more reflexive "model-free" system. A balance of control exerted by these systems is thought to be related to dopamine neurotransmission. However, in the absence of direct measures of human dopamine, it remains unknown whether this reflects a quantitative relation with dopamine either in the striatum or other brain areas. Using a sequential decision task performed during functional magnetic resonance imaging, combined with striatal measures of dopamine using [(18)F]DOPA positron emission tomography, we show that higher presynaptic ventral striatal dopamine levels were associated with a behavioral bias toward more model-based control. Higher presynaptic dopamine in ventral striatum was associated with greater coding of model-based signatures in lateral prefrontal cortex and diminished coding of model-free prediction errors in ventral striatum. Thus, interindividual variability in ventral striatal presynaptic dopamine reflects a balance in the behavioral expression and the neural signatures of model-free and model-based control. Our data provide a novel perspective on how alterations in presynaptic dopamine levels might be accompanied by a disruption of behavioral control as observed in aging or neuropsychiatric diseases such as schizophrenia and addiction.

Cellular Strategies of Protein Quality Control

PubMed Central

Chen, Bryan; Retzlaff, Marco; Roos, Thomas; Frydman, Judith

2011-01-01

Eukaryotic cells must contend with a continuous stream of misfolded proteins that compromise the cellular protein homeostasis balance and jeopardize cell viability. An elaborate network of molecular chaperones and protein degradation factors continually monitor and maintain the integrity of the proteome. Cellular protein quality control relies on three distinct yet interconnected strategies whereby misfolded proteins can either be refolded, degraded, or delivered to distinct quality control compartments that sequester potentially harmful misfolded species. Molecular chaperones play a critical role in determining the fate of misfolded proteins in the cell. Here, we discuss the spatial and temporal organization of cellular quality control strategies and their implications for human diseases linked to protein misfolding and aggregation. PMID:21746797

Dynamic regulation of erythropoiesis: A computer model of general applicability

NASA Technical Reports Server (NTRS)

Leonard, J. I.

1979-01-01

A mathematical model for the control of erythropoiesis was developed based on the balance between oxygen supply and demand at a renal oxygen detector which controls erythropoietin release and red cell production. Feedback regulation of tissue oxygen tension is accomplished by adjustments of hemoglobin levels resulting from the output of a renal-bone marrow controller. Special consideration was given to the determinants of tissue oxygenation including evaluation of the influence of blood flow, capillary diffusivity, oxygen uptake and oxygen-hemoglobin affinity. A theoretical analysis of the overall control system is presented. Computer simulations of altitude hypoxia, red cell infusion hyperoxia, and homolytic anemia demonstrate validity of the model for general human application in health and disease.

Auditory white noise reduces age-related fluctuations in balance.

PubMed

Ross, J M; Will, O J; McGann, Z; Balasubramaniam, R

2016-09-06

Fall prevention technologies have the potential to improve the lives of older adults. Because of the multisensory nature of human balance control, sensory therapies, including some involving tactile and auditory noise, are being explored that might reduce increased balance variability due to typical age-related sensory declines. Auditory white noise has previously been shown to reduce postural sway variability in healthy young adults. In the present experiment, we examined this treatment in young adults and typically aging older adults. We measured postural sway of healthy young adults and adults over the age of 65 years during silence and auditory white noise, with and without vision. Our results show reduced postural sway variability in young and older adults with auditory noise, even in the absence of vision. We show that vision and noise can reduce sway variability for both feedback-based and exploratory balance processes. In addition, we show changes with auditory noise in nonlinear patterns of sway in older adults that reflect what is more typical of young adults, and these changes did not interfere with the typical random walk behavior of sway. Our results suggest that auditory noise might be valuable for therapeutic and rehabilitative purposes in older adults with typical age-related balance variability. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Evaluation of human dynamic balance in Grassmann manifold

NASA Astrophysics Data System (ADS)

Michalczuk, Agnieszka; Wereszczyński, Kamil; Mucha, Romualda; Świtoński, Adam; Josiński, Henryk; Wojciechowski, Konrad

2017-07-01

The authors present an application of Grassmann manifold to the evaluation of human dynamic balance based on the time series representing movements of hip, knee and ankle joints in the sagittal, frontal and transverse planes. Time series were extracted from gait sequences which were recorded in the Human Motion Laboratory (HML) of the Polish-Japanese Academy of Information Technology in Bytom, Poland using the Vicon system.

Influence of job demands and job control on work-life balance among Taiwanese nurses.

PubMed

Ng, Lee-Peng; Chen, I-Chi; Ng, Hui-Fuang; Lin, Bo-Yen; Kuar, Lok-Sin

2017-09-01

This study investigated the extent to which the job demands and job control of nurses were related to their work-life balance. The inability to achieve work-life balance is one of the major reasons for the declining retention rate among nurses. Job demands and job control are two major work domain factors that can have a significant influence on the work-life balance of nurses. The study measured the job demands, job control and work-life balance of 2040 nurses in eight private hospitals in Taiwan in 2013. Job demands and job control significantly predicted all the dimensions of work-life balance. Job demands increased the level of work-life imbalance among nurses. While job control showed positive effects on work/personal life enhancement, it was found to increase both work interference with personal life and personal life interference with work. Reducing the level of job demands (particularly for psychological demands) between family and career development and maintaining a proper level of job control are essential to the work-life balance of nurses. Flexible work practices and team-based management could be considered by nursing management to lessen job demand pressure and to facilitate job engagement and participation among nurses, thus promoting a better balance between work and personal life. © 2017 John Wiley & Sons Ltd.

Application of infrared thermal imaging in the study of preventing cardiovascular and cerebrovascular diseases with Chinese medicine health food

NASA Astrophysics Data System (ADS)

Li, Ziru; Zhang, Xusheng

2009-08-01

To explore the assessing technique which could objectively reflect the characteristics of Chinese medicine in the prevention of cardiovascular and cerebrovascular diseases, four balance features of infrared thermal images (ITI) corresponding to the up and down, left and right, proximal and distal balance of blood circulation of human body were studied. First, the ITI features of the middle-aged and elderly people with lipid abnormality history were compared with those of the healthy youth. It was found that the balance state of the youth was significantly better than that of the middle-aged and elderly, P<=0.01 for all the balance features. For the youth, the balance state of females was better than that of the males. But this sexual difference disappeared for the middle-aged and elderly group. Second, a double-blind randomized trial was carried out to study the influences of Shengyi capsule, a Chinese medicine health food with the function of helping to decrease serum lipid, on the balance features. The subjects were middle-aged and elderly people with lipid abnormality history. Shengyi capsule was taken by the trial group while Xuezhikang capsule (with lovastatin as the main effective component) by the control group for 108 days. The balance features of ITI showed that Shengyi was significantly better than Xuezhikang in improving the whole body balance of blood circulation (including the up and down, left and right, proximal and distal balance). The relative efficacy rate was 81.0% for the trial group and 33.3% for the control group, there was significant difference between the two groups (P=0.002). Shengyi could effectively decrease the low density lipoprotein cholesterol (LDL-C) but the effect of Xuezhikang in decreasing total cholesterol (TC) and LDL-C was better than Shengyi. Though the lipid-lowering effect of Shengyi was not as good as Xuezhikang, ITI reflected the obvious advantage of Shengyi in improving the whole body balance of blood circulation which indicated that helping to decrease serum lipid is only part of the health function of Shengyi. The physiology and pathology basis of the influences of Shengyi on the four balance features and its relationship with the clinical outcome deserves further study. So the prospect of infrared thermal imaging is indicated as the suitable evaluation technique which could objectively reflect the whole balance regulation advantage of Chinese medicinal compounds.

Physical Activity Associated with Prayer Regimes Improves Standing Dynamic Balance of Healthy People

PubMed Central

AlAbdulwahab, Sami Saleh; Kachanathu, Shaji John; Oluseye, Kamaldeen

2014-01-01

[Purpose] Preparing for prayers, practicing religious meditation and performing prayers are believed to stimulate the visual, vestibular and somatosensory systems, which provide the sensory information that influences human balance. The purpose of this study was to determine the effect of the Islamic prayer regime on balance. [Subjects and Methods] Sixty healthy male subjects with a mean age of 31 ± 5 years and a mean body mass index of 27 ± 2 kg/cm2 voluntarily participated in this study. The subjects were divided into two equal groups: one group of subjects who regularly practiced Islamic prayer, and another group of non-practicing subjects. The dynamic balance of individuals in both groups was measured using a Balance Master. [Results] Adult healthy subjects practicing Islamic prayer regimes exhibited statistically significantly better dynamic balance than the non-practicing healthy subjects. [Conclusions] The results of this study support the hypothesis that religious meditation and prayers benefit human physiological function, especially balance. PMID:24409021

Effects of Balance Control Training on Functional Outcomes in Subacute Hemiparetic Stroke Patients.

PubMed

Huh, Jin Seok; Lee, Yang-Soo; Kim, Chul-Hyun; Min, Yu-Sun; Kang, Min-Gu; Jung, Tae-Du

2015-12-01

To investigate the efficacy of balance control training using a newly developed balance control trainer (BalPro) on the balance and gait of patients with subacute hemiparetic stroke. Forty-three subacute stroke patients were assigned to either a balance control training (BCT) group or a control group. The BCT group (n=23) was trained with BalPro for 30 minutes a day, 5 days a week for 2 weeks, and received one daily session of conventional physical therapy. The control group (n=20) received two sessions of conventional physical therapy every day for 2 weeks. The primary outcome was assessment with the Berg Balance Scale (BBS). Secondary outcomes were Functional Ambulation Category (FAC), the 6-minute walking test (6mWT), Timed Up and Go (TUG), the Korean version of Modified Barthel Index (K-MBI), and the manual muscle test (MMT) of the knee extensor. All outcome measures were evaluated before and after 2 weeks of training in both groups. There were statistically significant improvements in all parameters except MMT and FAC after 2 weeks of treatment in both groups. After training, the BCT group showed greater improvements in the BBS and the 6mWT than did the control group. Balance control training using BalPro could be a useful treatment for improving balance and gait in subacute hemiparetic stroke patients.

Measures of static postural control moderate the association of strength and power with functional dynamic balance.

PubMed

Forte, Roberta; Boreham, Colin A G; De Vito, Giuseppe; Ditroilo, Massimiliano; Pesce, Caterina

2014-12-01

Age-related reductions in strength and power are considered to negatively impact balance control, but the existence of a direct association is still an issue of debate. This is possibly due to the fact that balance assessment is complex, reflects different underlying physiologic mechanisms and involves quantitative measurements of postural sway or timing of performance during balance tasks. The present study evaluated the moderator effect of static postural control on the association of power and strength with dynamic balance tasks. Fifty-seven healthy 65-75 year old individuals performed tests of dynamic functional balance (walking speed under different conditions) and of strength, power and static postural control. Dynamic balance performance (walking speed) was associated with lower limb strength and power, as well as postural control under conditions requiring postural adjustments (narrow surface walking r(2) = 0.31, p < 0.001). An interaction effect between strength and static postural control was found with narrow surface walking and talking while walking (change of β 0.980, p < 0.001 in strength for 1 SD improvements in static postural control for narrow walking, and [Formula: see text] -0.730, p < 0.01 in talking while walking). These results indicate that good static postural control facilitates the utilisation of lower limb strength to better perform complex, dynamic functional balance tasks. Practical implications for assessment and training are discussed.

Effects of Balance Control Training on Functional Outcomes in Subacute Hemiparetic Stroke Patients

PubMed Central

Huh, Jin Seok; Lee, Yang-Soo; Kim, Chul-Hyun; Min, Yu-Sun; Kang, Min-Gu

2015-01-01

Objective To investigate the efficacy of balance control training using a newly developed balance control trainer (BalPro) on the balance and gait of patients with subacute hemiparetic stroke. Methods Forty-three subacute stroke patients were assigned to either a balance control training (BCT) group or a control group. The BCT group (n=23) was trained with BalPro for 30 minutes a day, 5 days a week for 2 weeks, and received one daily session of conventional physical therapy. The control group (n=20) received two sessions of conventional physical therapy every day for 2 weeks. The primary outcome was assessment with the Berg Balance Scale (BBS). Secondary outcomes were Functional Ambulation Category (FAC), the 6-minute walking test (6mWT), Timed Up and Go (TUG), the Korean version of Modified Barthel Index (K-MBI), and the manual muscle test (MMT) of the knee extensor. All outcome measures were evaluated before and after 2 weeks of training in both groups. Results There were statistically significant improvements in all parameters except MMT and FAC after 2 weeks of treatment in both groups. After training, the BCT group showed greater improvements in the BBS and the 6mWT than did the control group. Conclusion Balance control training using BalPro could be a useful treatment for improving balance and gait in subacute hemiparetic stroke patients. PMID:26798615

Specific balance training included in an endurance-resistance exercise program improves postural balance in elderly patients undergoing haemodialysis.

PubMed

Frih, Bechir; Mkacher, Wajdi; Jaafar, Hamdi; Frih, Ameur; Ben Salah, Zohra; El May, Mezry; Hammami, Mohamed

2018-04-01

The purpose of this study was to evaluate the effects of 6 months of specific balance training included in endurance-resistance program on postural balance in haemodialysis (HD) patients. Forty-nine male patients undergoing HD were randomly assigned to an intervention group (balance training included in an endurance-resistance training, n = 26) or a control group (resistance-endurance training only, n = 23). Postural control was assessed using six clinical tests; Timed Up and Go test, Tinetti Mobility Test, Berg Balance Scale, Unipodal Stance test, Mini-Balance Evaluation Systems Test and Activities Balance Confidence scale. All balance measures increased significantly after the period of rehabilitation training in the intervention group. Only the Timed Up and Go, Berg Balance Scale, Mini-Balance Evaluation Systems Test and Activities Balance Confidence scores were improved in the control group. The ranges of change in these tests were greater in the balance training group. In HD patients, specific balance training included in a usual endurance-resistance training program improves static and dynamic balance better than endurance-resistance training only. Implications for rehabilitation Rehabilitation using exercise in haemodialysis patients improved global mobility and functional abilities. Specific balance training included in usual endurance resistance training program could lead to improved static and dynamic balance.

Human responses to augmented virtual scaffolding models.

PubMed

Hsiao, Hongwei; Simeonov, Peter; Dotson, Brian; Ammons, Douglas; Kau, Tsui-Ying; Chiou, Sharon

2005-08-15

This study investigated the effect of adding real planks, in virtual scaffolding models of elevation, on human performance in a surround-screen virtual reality (SSVR) system. Twenty-four construction workers and 24 inexperienced controls performed walking tasks on real and virtual planks at three virtual heights (0, 6 m, 12 m) and two scaffolding-platform-width conditions (30, 60 cm). Gait patterns, walking instability measurements and cardiovascular reactivity were assessed. The results showed differences in human responses to real vs. virtual planks in walking patterns, instability score and heart-rate inter-beat intervals; it appeared that adding real planks in the SSVR virtual scaffolding model enhanced the quality of SSVR as a human - environment interface research tool. In addition, there were significant differences in performance between construction workers and the control group. The inexperienced participants were more unstable as compared to construction workers. Both groups increased their stride length with repetitions of the task, indicating a possibly confidence- or habit-related learning effect. The practical implications of this study are in the adoption of augmented virtual models of elevated construction environments for injury prevention research, and the development of programme for balance-control training to reduce the risk of falls at elevation before workers enter a construction job.

Assessment of postural balance function.

PubMed

Kostiukow, Anna; Rostkowska, Elzbieta; Samborski, Włodzimierz

2009-01-01

Postural balance is defined as the ability to stand unassisted without falling. Examination of the patient's postural balance function is a difficult diagnostic task. Most of the balance tests used in medicine provide incomplete information on this coordination ability of the human body. The aim of this study was to review methods of assessment of the patient's postural balance function, including various tests used in medical diagnostics centers.

The balance effect of acupuncture therapy among stroke patients.

PubMed

Huang, Shih-Wei; Wang, Wei-Te; Yang, Tsung-Hsien; Liou, Tsan-Hon; Chen, Guan-Yu; Lin, Li-Fong

2014-08-01

To analyze how acupuncture therapy affects balance in patients experiencing their first stroke and to identify the stroke group with greatest improvement in balance after acupuncture intervention. Retrospective case-control study. Ward of a medical university hospital. A total of 629 stroke patients were enrolled initially; 345 patients met the study criteria and 132 were analyzed (66 each in the study and control groups). The study group received physiotherapy combined with acupuncture and the control group received only physiotherapy. The Postural Assessment Scale for Stroke patients (PASS) was used to evaluate balance. This balance scale system can be subdivided into static balance (PASS-MP, maintain posture) and dynamic balance (PASS-CP, change posture). This study revealed no statistically significant improvement of balance in the study group (t test). When patients with high Brunnstrom stage (Br stage) and low Br stage were analyzed separately, once again no statistical difference was detected between the study and control groups of those with high Br stage. However, among low-Br stage patients, the study group showed significant improvement in static balance (mean PASS-MP score±standard deviation: 4.7±3.7) compared with the control group (PASS-MP score: 2.8±2.7) (p<0.05). In first-ever stroke patients with a low Br stage, acupuncture therapy can improve static balance during rehabilitation. However, the effect on balance was limited among high-Br stage patients. This study provides information valuable to patients with hemiplegic stroke because it suggests that acupuncture can be used to improve balance. A prospective double-blind, randomized, controlled study design is recommended for future studies in patients with hemiplegic stroke.

Inverted-U shaped dopamine actions on human working memory and cognitive control

PubMed Central

Cools, R; D’Esposito, M

2011-01-01

Brain dopamine has long been implicated in cognitive control processes, including working memory. However, the precise role of dopamine in cognition is not well understood, partly because there is large variability in the response to dopaminergic drugs both across different behaviors and across different individuals. We review evidence from a series of studies with experimental animals, healthy humans and patients with Parkinson’s disease, which highlight two important factors that contribute to this large variability. First, the existence of an optimum dopamine level for cognitive function implicates the need to take into account baseline levels of dopamine when isolating dopamine’s effects. Second, cognitive control is a multi-factorial phenomenon, requiring a dynamic balance between cognitive stability and cognitive flexibility. These distinct components might implicate the prefrontal cortex and the striatum respectively. Manipulating dopamine will thus have paradoxical consequences for distinct cognitive control processes depending on distinct basal or optimal levels of dopamine in different brain regions. PMID:21531388

Reduced-order modeling for hyperthermia: an extended balanced-realization-based approach.

PubMed

Mattingly, M; Bailey, E A; Dutton, A W; Roemer, R B; Devasia, S

1998-09-01

Accurate thermal models are needed in hyperthermia cancer treatments for such tasks as actuator and sensor placement design, parameter estimation, and feedback temperature control. The complexity of the human body produces full-order models which are too large for effective execution of these tasks, making use of reduced-order models necessary. However, standard balanced-realization (SBR)-based model reduction techniques require a priori knowledge of the particular placement of actuators and sensors for model reduction. Since placement design is intractable (computationally) on the full-order models, SBR techniques must use ad hoc placements. To alleviate this problem, an extended balanced-realization (EBR)-based model-order reduction approach is presented. The new technique allows model order reduction to be performed over all possible placement designs and does not require ad hoc placement designs. It is shown that models obtained using the EBR method are more robust to intratreatment changes in the placement of the applied power field than those models obtained using the SBR method.

Effect of acute fatigue of the hip abductors on control of balance in young and older women.

PubMed

Bellew, James W; Panwitz, Beth L; Peterson, Laura; Brock, Mary C; Olson, Katie E; Staples, William H

2009-07-01

To examine the effects of acute fatigue of the hip abductors on the control of balance in young and older women. Pretest-posttest. University research laboratory. Healthy young women (n=20; age, 23.0+/-1.5y; height, 166.52+/-4.5 cm; mass, 65.33+/-10.5 kg) and community-dwelling older women (n=20; age, 71.65+/-7.2y; height, 162.31+/-3.8 cm; mass, 71.16+/-11.6 kg) without a fall history. Measurements of control of single-limb balance before and after fatiguing the hip abductors of the dominant leg. Performance on 3 clinical assessments of control of balance: the modified Functional Reach Test in the forward, left, and right directions; the Lower-Extremity Reach Test in forward and lateral directions; and the Single-Limb Stance Time Test (SLSTT). Although the younger subjects showed a significantly greater control of balance than the older women in most tests, control of balance after acute fatigue failed to show a significant decline in either age group. The only exception to this was the SLSTT in the younger women in whom a significant 26% decline was noted (P<.05). Acute fatigue of the hip abductors did not result in a decreased control of balance in healthy young or older women without fall history. Despite considerable changes in movement strategies used to complete the postfatigue tests of balance, quantitative measures of balance did not decrease.

Cortical processes associated with continuous balance control as revealed by EEG spectral power.

PubMed

Hülsdünker, T; Mierau, A; Neeb, C; Kleinöder, H; Strüder, H K

2015-04-10

Balance is a crucial component in numerous every day activities such as locomotion. Previous research has reported distinct changes in cortical theta activity during transient balance instability. However, there remains little understanding of the neural mechanisms underlying continuous balance control. This study aimed to investigate cortical theta activity during varying difficulties of continuous balance tasks, as well as examining the relationship between theta activity and balance performance. 37 subjects completed nine balance tasks with different levels of surface stability and base of support. Throughout the balancing task, electroencephalogram (EEG) was recorded from 32 scalp locations. ICA-based artifact rejection was applied and spectral power was analyzed in the theta frequency band. Theta power increased in the frontal, central, and parietal regions of the cortex when balance tasks became more challenging. In addition, fronto-central and centro-parietal theta power correlated with balance performance. This study demonstrates the involvement of the cerebral cortex in maintaining upright posture during continuous balance tasks. Specifically, the results emphasize the important role of frontal and parietal theta oscillations in balance control. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

EMERGY-based environmental systems assessment of a multi-purpose temperate mixed-forest watershed of the southern Appalachian Mountains, USA.

PubMed

Tilley, David Rogers; Swank, Wayne T

2003-11-01

Emergy (with an 'm') synthesis was used to assess the balance between nature and humanity and the equity among forest outcomes of a US Forest Service ecosystem management demonstration project on the Wine Spring Creek watershed, a high-elevation (1600 m), temperate forest located in the southern Appalachian mountains of North Carolina, USA. EM embraces a holistic perspective, accounting for the multiple temporal and spatial scales of forest processes and public interactions, to balance the ecological, economic, and social demands placed on land resources. Emergy synthesis is a modeling tool that allows the structure and function of forest ecosystems to be quantified in common units (solar emergy-joules, sej) for easy and meaningful comparison, determining 'system-value' for forcing factors, components, and processes based on the amount of resources required to develop and sustain them, whether they are money, material, energy, or information. The Environmental Loading Ratio (ELR), the units of solar emergy imported into the watershed via human control per unit of indigenous, natural solar emergy, was determined to be 0.42, indicating that the load on the natural environment was not ecologically damaging and that excess ecological capacity existed for increasing non-ecological activities (e.g. timbering, recreation) to achieve an ELR of 1.0 (perfect ecological-economic balance). Three forest outcomes selected to represent the three categories of desired sustainability (ecological, economic, and social) were evaluated in terms of their solar emergy flow to measure outcome equity. Direct economic contribution was an order of magnitude less (224 x 10(12)solar emergy-joules (sej) ha(-1)) than the ecological and social contributions, which were provided at annual rates of 3083 and 2102 x 10(12)sejha(-1), respectively. Emergy synthesis was demonstrated to holistically integrate and quantify the interconnections of a coupled nature-human system allowing the goals of ecological balance and outcome equity to be measured quantitatively.

Comparative Effects of Different Balance-Training-Progression Styles on Postural Control and Ankle Force Production: A Randomized Controlled Trial.

PubMed

Cuğ, Mutlu; Duncan, Ashley; Wikstrom, Erik

2016-02-01

Despite the effectiveness of balance training, the exact parameters needed to maximize the benefits of such programs remain unknown. One such factor is how individuals should progress to higher levels of task difficulty within a balance-training program. Yet no investigators have directly compared different balance-training-progression styles. To compare an error-based progression (ie, advance when proficient at a task) with a repetition-based progression (ie, advance after a set amount of repetitions) style during a balance-training program in healthy individuals. Randomized controlled trial. Research laboratory. A total of 28 (16 women, 12 men) physically healthy young adults (age = 21.57 ± 3.95 years, height = 171.60 ± 11.03 cm, weight = 72.96 ± 16.18 kg, body mass index = 24.53 ± 3.7). All participants completed 12 supervised balance-training sessions over 4 weeks. Each session consisted of a combination of dynamic unstable-surface tasks that incorporated a BOSU ball and lasted about 30 minutes. Static balance from an instrumented force plate, dynamic balance as measured via the Star Excursion Balance Test, and ankle force production in all 4 cardinal planes of motion as measured with a handheld dynamometer before and after the intervention. Selected static postural-control outcomes, dynamic postural control, and ankle force production in all planes of motion improved (P < .05). However, no differences between the progression styles were observed (P > .05) for any of the outcome measures. A 4-week balance-training program consisting of dynamic unstable-surface exercises on a BOSU ball improved dynamic postural control and ankle force production in healthy young adults. These results suggest that an error-based balance-training program is comparable with but not superior to a repetition-based balance-training program in improving postural control and ankle force production in healthy young adults.

Bath Breakfast Project (BBP)--examining the role of extended daily fasting in human energy balance and associated health outcomes: study protocol for a randomised controlled trial [ISRCTN31521726].

PubMed

Betts, James A; Thompson, Dylan; Richardson, Judith D; Chowdhury, Enhad A; Jeans, Matthew; Holman, Geoffrey D; Tsintzas, Kostas

2011-07-08

Current guidance regarding the role of daily breakfast in human health is largely grounded in cross-sectional observations. However, the causal nature of these relationships has not been fully explored and what limited information is emerging from controlled laboratory-based experiments appears inconsistent with much existing data. Further progress in our understanding therefore requires a direct examination of how daily breakfast impacts human health under free-living conditions. The Bath Breakfast Project (BBP) is a randomised controlled trial comparing the effects of daily breakfast consumption relative to extended fasting on energy balance and human health. Approximately 70 men and women will undergo extensive laboratory-based assessments of their acute metabolic responses under fasted and post-prandial conditions, to include: resting metabolic rate, substrate oxidation, dietary-induced thermogenesis and systemic concentrations of key metabolites/hormones. Physiological and psychological indices of appetite will also be monitored both over the first few hours of the day (i.e. whether fed or fasted) and also following a standardised test lunch used to assess voluntary energy intake under controlled conditions. Baseline measurements of participants' anthropometric characteristics (e.g. DEXA) will be recorded prior to intervention, along with an oral glucose tolerance test and acquisition of adipose tissue samples to determine expression of key genes and estimates of tissue-specific insulin action. Participants will then be randomly assigned either to a group prescribed an energy intake of ≥3000 kJ before 1100 each day or a group to extend their overnight fast by abstaining from ingestion of energy-providing nutrients until 1200 each day, with all laboratory-based measurements followed-up 6 weeks later. Free-living assessments of energy intake (via direct weighed food diaries) and energy expenditure (via combined heart-rate/accelerometry) will be made during the first and last week of intervention, with continuous glucose monitors worn both to document chronic glycaemic responses to the intervention and to verify compliance.

Comparison of soymilk, powdered milk, Hank's balanced salt solution and tap water on periodontal ligament cell survival.

PubMed

Moazami, Fariborz; Mirhadi, Hosein; Geramizadeh, Bita; Sahebi, Safoura

2012-04-01

The purpose of this study was to evaluate the ability of soymilk, powdered milk, and Hank's balanced salt solution (HBSS) to maintain human periodontal ligament (PDL) cell viability in vitro. PDL cells were obtained from extracted healthy third molars and cultured in Dulbecco's modified Eagles medium (DMEM). The cultures were exposed for 1, 2, 4, and 8 h to experimental solutions (tap water served as negative control and DMEM as positive control) at 37°C. The viable cells were then counted using the trypan blue exclusion technique. Data were analyzed by using one-way anova, post hoc Scheffe and two-way anova test. Statistical analysis showed that HBSS, powdered baby formula, and soymilk maintain cell viability equally well in different periods of times. Tap water cannot keep cells viable as well as other solutions. Soymilk and powdered baby formula can be recommended as suitable storage media for avulsed teeth for up to 8 h. © 2011 John Wiley & Sons A/S.

Antimicrobial Active Clothes Display No Adverse Effects on the Ecological Balance of the Healthy Human Skin Microflora

PubMed Central

Hoefer, Dirk; Hammer, Timo R.

2011-01-01

The progressive public use of antimicrobial clothes has raised issues concerning skin health. A placebo-controlled side-to-side study was run with antimicrobial clothes versus fabrics of similar structure but minus the antimicrobial activity, to evaluate possible adverse effects on the healthy skin microflora. Sixty volunteers were enrolled. Each participant received a set of form-fitting T-shirts constructed in 2 halves: an antibacterial half, displaying activities of 3–5 log-step reductions due to silver-finishes or silver-loaded fibres and a nonantibacterial control side. The microflora of the scapular skin was analyzed weekly for opportunistic and pathogenic microorganisms over six weeks. The antibacterial halves did not disturb the microflora in number or composition, whereas a silver-containing deodorant displayed a short-term disturbance. Furthermore, parameters of skin morphology and function (TEWL, pH, moisture) did not show any significant shifts. In summary, antimicrobial clothes did not show adverse effects on the ecological balance of the healthy skin microflora. PMID:22363849

Searching for ancient balanced polymorphisms shared between Neanderthals and Modern Humans

PubMed Central

Viscardi, Lucas Henriques; Paixão-Côrtes, Vanessa Rodrigues; Comas, David; Salzano, Francisco Mauro; Rovaris, Diego; Bau, Claiton Dotto; Amorim, Carlos Eduardo G.; Bortolini, Maria Cátira

2018-01-01

Abstract Hominin evolution is characterized by adaptive solutions often rooted in behavioral and cognitive changes. If balancing selection had an important and long-lasting impact on the evolution of these traits, it can be hypothesized that genes associated with them should carry an excess of shared polymorphisms (trans- SNPs) across recent Homo species. In this study, we investigate the role of balancing selection in human evolution using available exomes from modern (Homo sapiens) and archaic humans (H. neanderthalensis and Denisovan) for an excess of trans-SNP in two gene sets: one associated with the immune system (IMMS) and another one with behavioral system (BEHS). We identified a significant excess of trans-SNPs in IMMS (N=547), of which six of these located within genes previously associated with schizophrenia. No excess of trans-SNPs was found in BEHS, but five genes in this system harbor potential signals for balancing selection and are associated with psychiatric or neurodevelopmental disorders. Our approach evidenced recent Homo trans-SNPs that have been previously implicated in psychiatric diseases such as schizophrenia, suggesting that a genetic repertoire common to the immune and behavioral systems could have been maintained by balancing selection starting before the split between archaic and modern humans. PMID:29658973

Human Health and the Environment: In Harmony or in Conflict?

PubMed Central

Resnik, David B

2009-01-01

Health policy frameworks usually construe environmental protection and human health as harmonious values. Policies that protect the environment, such as pollution control and pesticide regulation, also benefit human health. In recent years, however, it has become apparent that promoting human health sometimes undermines environmental protection. Some actions, policies, or technologies that reduce human morbidity, mortality, and disease can have detrimental effects on the environment. Since human health and environmental protection are sometimes at odds, political leaders, citizens, and government officials need a way to mediate and resolve conflicts between these values. Unfortunately, few approaches to applied bioethics have the conceptual tools to do accomplish this task. Theories of health care ethics have little to say about the environment, and theories of environmental ethics don't say much about human health. In this essay, I defend an approach to ethical decision-making that gives policy-makers some tools for balancing promotion of human health and protection of the environment. PMID:19130245

Genetic Evidence of Human Adaptation to a Cooked Diet

PubMed Central

Carmody, Rachel N.; Dannemann, Michael; Briggs, Adrian W.; Nickel, Birgit; Groopman, Emily E.; Wrangham, Richard W.; Kelso, Janet

2016-01-01

Humans have been argued to be biologically adapted to a cooked diet, but this hypothesis has not been tested at the molecular level. Here, we combine controlled feeding experiments in mice with comparative primate genomics to show that consumption of a cooked diet influences gene expression and that affected genes bear signals of positive selection in the human lineage. Liver gene expression profiles in mice fed standardized diets of meat or tuber were affected by food type and cooking, but not by caloric intake or consumer energy balance. Genes affected by cooking were highly correlated with genes known to be differentially expressed in liver between humans and other primates, and more genes in this overlap set show signals of positive selection in humans than would be expected by chance. Sequence changes in the genes under selection appear before the split between modern humans and two archaic human groups, Neandertals and Denisovans, supporting the idea that human adaptation to a cooked diet had begun by at least 275,000 years ago. PMID:26979798

30 CFR 817.45 - Hydrologic balance: Sediment control measures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Hydrologic balance: Sediment control measures. 817.45 Section 817.45 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT...-UNDERGROUND MINING ACTIVITIES § 817.45 Hydrologic balance: Sediment control measures. (a) Appropriate sediment...

30 CFR 816.45 - Hydrologic balance: Sediment control measures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Hydrologic balance: Sediment control measures. 816.45 Section 816.45 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT...-SURFACE MINING ACTIVITIES § 816.45 Hydrologic balance: Sediment control measures. (a) Appropriate sediment...

30 CFR 816.45 - Hydrologic balance: Sediment control measures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Sediment control measures. 816.45 Section 816.45 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT...-SURFACE MINING ACTIVITIES § 816.45 Hydrologic balance: Sediment control measures. (a) Appropriate sediment...

30 CFR 817.45 - Hydrologic balance: Sediment control measures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Hydrologic balance: Sediment control measures. 817.45 Section 817.45 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT...-UNDERGROUND MINING ACTIVITIES § 817.45 Hydrologic balance: Sediment control measures. (a) Appropriate sediment...

The effects of whole body vibration combined biofeedback postural control training on the balance ability and gait ability in stroke patients.

PubMed

Uhm, Yo-Han; Yang, Dae-Jung

2017-11-01

[Purpose] The purpose of this study was to examine the effect of biofeedback postural control training using whole body vibration in acute stroke patients on balance and gait ability. [Subjects and Methods] Thirty stroke patients participated in this study and were divided into a group of 10, a group for biofeedback postural control training combined with a whole body vibration, one for biofeedback postural control training combined with an aero-step, and one for biofeedback postural control training. Biorescue was used to measure the limits of stability, balance ability, and Lukotronic was used to measure step length, gait ability. [Results] In the comparison of balance ability and gait ability between the groups for before and after intervention, Group I showed a significant difference in balance ability and gait ability compared to Groups II and III. [Conclusion] This study showed that biofeedback postural control training using whole body vibration is effective for improving balance ability and gait ability in stroke patients.

Brief Report: Interleukin-17A-Dependent Asymmetric Stem Cell Divisions Are Increased in Human Psoriasis: A Mechanism Underlying Benign Hyperproliferation.

PubMed

Charruyer, Alexandra; Fong, Stephen; Vitcov, Giselle G; Sklar, Samuel; Tabernik, Leah; Taneja, Monica; Caputo, Melinda; Soeung, Catherine; Yue, Lili; Uchida, Yoshi; Arron, Sarah T; Horton, Karen M; Foster, Robert D; Sano, Shigetoshi; North, Jeffrey P; Ghadially, Ruby

2017-08-01

The balance between asymmetric and symmetric stem cell (SC) divisions is key to tissue homeostasis, and dysregulation of this balance has been shown in cancers. We hypothesized that the balance between asymmetric cell divisions (ACDs) and symmetric cell divisions (SCDs) would be dysregulated in the benign hyperproliferation of psoriasis. We found that, while SCDs were increased in squamous cell carcinoma (SCC) (human and murine), ACDs were increased in the benign hyperproliferation of psoriasis (human and murine). Furthermore, while sonic hedgehog (linked to human cancer) and pifithrinα (p53 inhibitor) promoted SCDs, interleukin (IL)-1α and amphiregulin (associated with benign epidermal hyperproliferation) promoted ACDs. While there was dysregulation of the ACD:SCD ratio, no change in SC frequency was detected in epidermis from psoriasis patients, or in human keratinocytes treated with IL-1α or amphiregulin. We investigated the mechanism whereby immune alterations of psoriasis result in ACDs. IL17 inhibitors are effective new therapies for psoriasis. We found that IL17A increased ACDs in human keratinocytes. Additionally, studies in the imiquimod-induced psoriasis-like mouse model revealed that ACDs in psoriasis are IL17A-dependent. In summary, our studies suggest an association between benign hyperproliferation and increased ACDs. This work begins to elucidate the mechanisms by which immune alteration can induce keratinocyte hyperproliferation. Altogether, this work affirms that a finely tuned balance of ACDs and SCDs is important and that manipulating this balance may constitute an effective treatment strategy for hyperproliferative diseases. Stem Cells 2017;35:2001-2007. © 2017 AlphaMed Press.

Do kinematic metrics of walking balance adapt to perturbed optical flow?

PubMed

Thompson, Jessica D; Franz, Jason R

2017-08-01

Visual (i.e., optical flow) perturbations can be used to study balance control and balance deficits. However, it remains unclear whether walking balance control adapts to such perturbations over time. Our purpose was to investigate the propensity for visuomotor adaptation in walking balance control using prolonged exposure to optical flow perturbations. Ten subjects (age: 25.4±3.8years) walked on a treadmill while watching a speed-matched virtual hallway with and without continuous mediolateral optical flow perturbations of three different amplitudes. Each of three perturbation trials consisted of 8min of prolonged exposure followed by 1min of unperturbed walking. Using 3D motion capture, we analyzed changes in foot placement kinematics and mediolateral sacrum motion. At their onset, perturbations elicited wider and shorter steps, alluding to a more cautious, general anticipatory balance control strategy. As perturbations continued, foot placement tended toward values seen during unperturbed walking while step width variability and mediolateral sacrum motion concurrently increased. Our findings suggest that subjects progressively shifted from a general anticipatory balance control strategy to a reactive, task-specific strategy using step-to-step adjustments. Prolonged exposure to optical flow perturbations may have clinical utility to reinforce reactive, task-specific balance control through training. Copyright © 2017 Elsevier B.V. All rights reserved.

Impaired postural balance correlates with complex walking performance in mildly disabled persons with multiple sclerosis.

PubMed

Brincks, John; Andersen, Elisabeth Due; Sørensen, Henrik; Dalgas, Ulrik

2017-01-01

It is relevant to understand the possible influence of impaired postural balance on walking performance in multiple sclerosis (MS) gait rehabilitation. We expected associations between impaired postural balance and complex walking performance in mildly disabled persons with MS, but not in healthy controls. Thirteen persons with MS (Expanded Disability Status Scale = 2.5) and 13 healthy controls' walking performance were measured at fast walking speed, Timed Up & Go and Timed 25 Feet Walking. Postural balance was measured by stabilometry, 95% confidence ellipse sway area and sway velocity. Except from sway velocity (p = 0.07), significant differences were found between persons with MS and healthy controls in postural balance and walking. Significant correlations were observed between sway area and Timed Up & Go (r = 0.67) and fastest safe walking speed (r = -0.63) in persons with MS but not in healthy controls (r = 0.52 and r = 0.24, respectively). No other significant correlations were observed between postural balance and walking performance in neither persons with MS nor healthy controls. Findings add to the understanding of postural balance and walking in persons with MS, as impaired postural balance was related to complex walking performance. Exercises addressing impaired postural balance are encouraged in early MS gait rehabilitation.

Fibromyalgia is Associated with Impaired Balance and Falls

PubMed Central

Jones, Kim D.; Horak, Fay B.; Winters, Kerri Stone; Morea, Jessica M.; Bennett, Robert M.

2010-01-01

Background/Objective The purpose of this study was to determine whether FM patients differ from matched healthy controls in clinical tests of balance ability and fall frequency. Methods 34 FM patients and 32 age matched controls were administered the Balance Evaluation-Systems Test (BESTest), rated their balance confidence with the Activities-Specific Balance Confidence Scale (ABC) and reported the number of falls in the last 6 months. The Fibromyalgia Impact Questionnaire (FIQ) was used to assess FM severity. Results FM patients had significantly impaired balance in all components of the BESTest compared to controls. They also scored more poorly on balance confidence. Overall fibromyalgia severity (FIQ) correlated significantly with the BESTest, and the ABC scale. The BESTest and ABC correlated significantly with 6 commonly reported FM symptoms (excluding pain). FM patients reported a total of 37 falls over the last six-months compared to 6 falls in healthy controls. Conclusion Fibromyalgia is associated with balance problems and increased fall frequency. Patients were aware of their balance problems. These results suggest that FM may affect peripheral and/or central mechanisms of postural control. Further objective study is needed to identify the relative contributions of neural and musculoskeletal impairments to postural stability in FM, thus providing clinicians with exercise prescriptions that maximize postural stability. PMID:19125137

Trunk repositioning errors are increased in balance-impaired older adults.

PubMed

Goldberg, Allon; Hernandez, Manuel Enrique; Alexander, Neil B

2005-10-01

Controlling the flexing trunk is critical in recovering from a loss of balance and avoiding a fall. To investigate the relationship between trunk control and balance in older adults, we measured trunk repositioning accuracy in young and balance-impaired and unimpaired older adults. Young adults (N = 8, mean age 24.3 years) and two groups of community-dwelling older adults defined by unipedal stance time (UST)-a balance-unimpaired group (UST > 30 seconds, N = 7, mean age 73.9 years) and a balance-impaired group (UST < 5 seconds, N = 8, mean age 79.6 years)-were tested in standing trunk control ability by reproducing a approximately 30 degrees trunk flexion angle under three visual-surface conditions: eyes opened and closed on the floor, and eyes opened on foam. Errors in reproducing the angle were defined as trunk repositioning errors (TREs). Clinical measures related to balance, trunk extensor strength, and self-reported disability were obtained. TREs were significantly greater in the balance-impaired group than in the other groups, even when controlling for trunk extensor strength and body mass. In older adults, there were significant correlations between TREs and three clinical measures of balance and fall risk, UST and maximum step length (-0.65 to -0.75), and Timed Up & Go score (0.55), and between TREs and age (0.63-0.76). In each group TREs were similar under the three visual-surface conditions. Test-retest reliability for TREs was good to excellent (intraclass correlation coefficients > or =0.74). Older balance-impaired adults have larger TREs, and thus poorer trunk control, than do balance-unimpaired older individuals. TREs are reliable and valid measures of underlying balance impairment in older adults, and may eventually prove to be useful in predicting the ability to recover from losses of balance and to avoid falls.

Immediate effects of cryotherapy on static and dynamic balance.

PubMed

Douglas, Matthew; Bivens, Serena; Pesterfield, Jennifer; Clemson, Nathan; Castle, Whitney; Sole, Gisela; Wassinger, Craig A

2013-02-01

Cryotherapy is commonly used in physical therapy with many known benefits; however several investigations have reported decreased functional performance following therapeutic application thereof. The purpose of this study was to determine the effect of cryotherapy applied to the ankle on static and dynamic standing balance. It was hypothesized that balance would be decreased after cryotherapy application. Twenty individuals (aged 18 to 40 years) participated in this research project. Each participant was tested under two conditions: an experimental condition where subjects received ice water immersion of the foot and ankle for 15 minutes immediately before balance testing and a control condition completed at room temperature. A Biodex® Balance System was used to quantify balance using anterior/posterior (AP), medial/lateral (ML), and overall balance indices. Paired t-tests were used to compare the balance indices for the two conditions with alpha set at 0.05 a priori. Effect size was also calculated to account for the multiple comparisons made. The static balance indices did not display statistically significant differences between the post-cryotherapy and the control conditions with low effect sizes. Dynamic ML indices significantly increased following the cryotherapy application compared to the control exhibiting a moderate effect size indicating decreased balance following cryotherapy application. No differences were noted between experimental and control conditions for the dynamic AP or overall balance indices while a small effect size was noted for both. The results suggest that cryotherapy to the ankle has a negative effect on the ML component of dynamic balance following ice water immersion. Immediate return to play following cryotherapy application is cautioned given the decreased dynamic ML balance and potential for increased injury risk. 3b Case-control study.

Heat balance model for a human body in the form of wet bulb globe temperature indices.

PubMed

Sakoi, Tomonori; Mochida, Tohru; Kurazumi, Yoshihito; Kuwabara, Kohei; Horiba, Yosuke; Sawada, Shin-Ichi

2018-01-01

The purpose of this study is to expand the empirically derived wet bulb globe temperature (WBGT) index to a rational thermal index based on the heat balance for a human body. We derive the heat balance model in the same form as the WBGT for a human engaged in moderate intensity work with a metabolic heat production of 174W/m 2 while wearing typical vapor-permeable clothing under shady and sunny conditions. Two important relationships are revealed based on this derivation: (1) the natural wet bulb and black globe temperature coefficients in the WBGT coincide with the heat balance equation for a human body with a fixed skin wettedness of approximately 0.45 at a fixed skin temperature; and (2) the WBGT can be interpreted as the environmental potential to increase skin temperature rather than the heat storage rate of a human body. We propose an adjustment factor calculation method that supports the application of WBGT for humans dressed in various clothing types and working under various air velocity conditions. Concurrently, we note difficulties in adjusting the WBGT by using a single factor for humans wearing vapor-impermeable protective clothing. The WBGT for shady conditions does not need adjustment depending on the positive radiant field (i.e., when a radiant heat source exists), whereas that for the sunny condition requires adjustments because it underestimates heat stress, which may result in insufficient human protection measures. Copyright © 2017 Elsevier Ltd. All rights reserved.

The relationship between balance confidence and control in individuals with Parkinson's disease.

PubMed

Lee, Hyo Keun; Altmann, Lori J P; McFarland, Nikolaus; Hass, Chris J

2016-05-01

A broad range of subjective and objective assessments have been used to assess balance confidence and balance control in persons with Parkinson's disease (PD). However, little is known about the relationship between self-perceived balance confidence and actual balance control in PD. The purpose of this investigation was to determine the relationship between self-perceived balance confidence and objectively measured static/dynamic balance control abilities. Forty-four individuals with PD participated in the study. Patients were stratified into 2 groups based on the modified Hoehn and Yahr (H&Y) disability score: early stage, H&Y ≤ 2.0 and moderate stage, H&Y ≥ 2.5. All participants completed the activities-specific balance confidence (ABC) scale and performed standing balance and gait initiation tasks to assess static and dynamic balance control. The center of pressure (COP) sway (CE95%Sway) during static balance and the peak distance between the projections of the COP and the center of mass (COM) in the transverse plane (COPCOM) during gait initiation were calculated. Pearson correlation analyses were conducted relating the ABC score and CE95%Sway and COPCOM. For early stage PD, there was a moderate correlation between ABC score and CE95%Sway (r = -0.56, R(2) = 0.32, p = 0.002), while no significant correlation was found between ABC score and COPCOM (r = -0.24, R(2) = 0.06, p = 0.227). For moderate stage PD, there was a moderate correlation between ABC score and COPCOM (r = 0.49, R(2) = 0.24, p = 0.044), while no correlation was found between ABC score and CE95%Sway (r = -0.19, R(2) = 0.04, p = 0.478). Individuals with different disease severities showed different relationships between balance confidence and actual static/dynamic balance control. Copyright © 2016 Elsevier Ltd. All rights reserved.

Results from the Joint US/Russian Sensory-Motor Investigations

NASA Technical Reports Server (NTRS)

1997-01-01

In this session, Session FA3, the discussion focuses on the following topics: The Effect of Long Duration Space Flight on the Acquisition of Predictable Targets in Three Dimensional Space; Effects of Microgravity on Spinal Reflex Mechanisms; Three Dimensional Head Movement Control During Locomotion After Long-Duration Space Flight; Human Body Shock Wave Transmission Properties After Long Duration Space Flight; Adaptation of Neuromuscular Activation Patterns During Locomotion After Long Duration Space Flight; Balance Control Deficits Following Long-Duration Space Flight; Influence of Weightlessness on Postural Muscular Activity Coordination; and The Use of Inflight Foot Pressure as a Countermeasure to Neuromuscular Degradation.

The Southern Ocean biogeochemical divide.

PubMed

Marinov, I; Gnanadesikan, A; Toggweiler, J R; Sarmiento, J L

2006-06-22

Modelling studies have demonstrated that the nutrient and carbon cycles in the Southern Ocean play a central role in setting the air-sea balance of CO(2) and global biological production. Box model studies first pointed out that an increase in nutrient utilization in the high latitudes results in a strong decrease in the atmospheric carbon dioxide partial pressure (pCO2). This early research led to two important ideas: high latitude regions are more important in determining atmospheric pCO2 than low latitudes, despite their much smaller area, and nutrient utilization and atmospheric pCO2 are tightly linked. Subsequent general circulation model simulations show that the Southern Ocean is the most important high latitude region in controlling pre-industrial atmospheric CO(2) because it serves as a lid to a larger volume of the deep ocean. Other studies point out the crucial role of the Southern Ocean in the uptake and storage of anthropogenic carbon dioxide and in controlling global biological production. Here we probe the system to determine whether certain regions of the Southern Ocean are more critical than others for air-sea CO(2) balance and the biological export production, by increasing surface nutrient drawdown in an ocean general circulation model. We demonstrate that atmospheric CO(2) and global biological export production are controlled by different regions of the Southern Ocean. The air-sea balance of carbon dioxide is controlled mainly by the biological pump and circulation in the Antarctic deep-water formation region, whereas global export production is controlled mainly by the biological pump and circulation in the Subantarctic intermediate and mode water formation region. The existence of this biogeochemical divide separating the Antarctic from the Subantarctic suggests that it may be possible for climate change or human intervention to modify one of these without greatly altering the other.

Sanitation in wilderness: Balancing minimum tool policies and wilderness values

Treesearch

Paul R. Lachapelle

2000-01-01

Officials with the four wilderness managing agencies are faced with balancing wilderness preservation values and the minimum tool policies of their respective agencies. One example is the management of sanitation, particularly human waste and the often intrusive infrastructure that accompanies its treatment and disposal. Because the treatment and disposal of human...

Regulation of lipid deposition in farm animals: Parallels between agriculture and human physiology

PubMed Central

Brandebourg, Terry D

2016-01-01

For many years, clinically oriented scientists and animal scientists have focused on lipid metabolism and fat deposition in various fat depots. While dealing with a common biology across species, the goals of biomedical and food animals lipid metabolism research differ in emphasis. In humans, mechanisms and regulation of fat synthesis, accumulation of fat in regional fat depots, lipid metabolism and dysmetabolism in adipose, liver and cardiac tissues have been investigated. Further, energy balance and weight control have also been extensively explored in humans. Finally, obesity and associated maladies including high cholesterol and atherosclerosis, cardiovascular disease, insulin resistance, hypertension, metabolic syndrome and health outcomes have been widely studied. In food animals, the emphasis has been on regulation of fatty acid synthesis and lipid deposition in fat depots and deposition of intramuscular fat. For humans, understanding the regulation of energy balance and body weight and of prevention or treatment of obesity and associated maladies have been important clinical outcomes. In production of food animals lowering fat content in muscle foods while enhancing intramuscular fat (marbling) have been major targets. In this review, we summarize how our laboratories have addressed the goal of providing lean but yet tasty and juicy muscle food products to consumers. In addition, we here describe efforts in the development of a new porcine model to study regulation of fat metabolism and obesity. Commonalities and differences in regulation of lipid metabolism between humans, rodents and food animals are emphasized throughout this review. PMID:27302175

Human-centred approaches in slipperiness measurement

PubMed Central

Grönqvist, Raoul; Abeysekera, John; Gard, Gunvor; Hsiang, Simon M.; Leamon, Tom B.; Newman, Dava J.; Gielo-Perczak, Krystyna; Lockhart, Thurmon E.; Pai, Clive Y.-C.

2010-01-01

A number of human-centred methodologies—subjective, objective, and combined—are used for slipperiness measurement. They comprise a variety of approaches from biomechanically-oriented experiments to psychophysical tests and subjective evaluations. The objective of this paper is to review some of the research done in the field, including such topics as awareness and perception of slipperiness, postural and balance control, rating scales for balance, adaptation to slippery conditions, measurement of unexpected movements, kinematics of slipping, and protective movements during falling. The role of human factors in slips and falls will be discussed. Strengths and weaknesses of human-centred approaches in relation to mechanical slip test methodologies are considered. Current friction-based criteria and thresholds for walking without slipping are reviewed for a number of work tasks. These include activities such as walking on a level or an inclined surface, running, stopping and jumping, as well as stair ascent and descent, manual exertion (pushing and pulling, load carrying, lifting) and particular concerns of the elderly and mobility disabled persons. Some future directions for slipperiness measurement and research in the field of slips and falls are outlined. Human-centred approaches for slipperiness measurement do have many applications. First, they are utilized to develop research hypotheses and models to predict workplace risks caused by slipping. Second, they are important alternatives to apparatus-based friction measurements and are used to validate such methodologies. Third, they are used as practical tools for evaluating and monitoring slip resistance properties of foot wear, anti-skid devices and floor surfaces. PMID:11794763

US Army Institute of Surgical Research Annual Research Progress Report for Fiscal Year 1988

DTIC Science & Technology

1988-10-01

promote anabolism in surgical patients. Patients (n=9) received a constant parenteral infusion of a hypocaloric diet which provided 1100 kcal/24 h...Protropin ) in calorie-deprived human volunteers illustrated its anabolic effect. Hypocaloric parenteral nutrition resulted in negative balance of nitrogen...human growth hormone. Lancet I(7062):7-12, 1959. 5. Manson JM and Wilmore DW: Positive nitrogen balance with human growth hormone and hypocaloric

Components of Standing Postural Control Evaluated in Pediatric Balance Measures: A Scoping Review.

PubMed

Sibley, Kathryn M; Beauchamp, Marla K; Van Ooteghem, Karen; Paterson, Marie; Wittmeier, Kristy D

2017-10-01

To identify measures of standing balance validated in pediatric populations, and to determine the components of postural control captured in each tool. Electronic searches of MEDLINE, Embase, and CINAHL databases using key word combinations of postural balance/equilibrium, psychometrics/reproducibility of results/predictive value of tests, and child/pediatrics; gray literature; and hand searches. Inclusion criteria were measures with a stated objective to assess balance, with pediatric (≤18y) populations, with at least 1 psychometric evaluation, with at least 1 standing task, with a standardized protocol and evaluation criteria, and published in English. Two reviewers independently identified studies for inclusion. There were 21 measures included. Two reviewers extracted descriptive characteristics, and 2 investigators independently coded components of balance in each measure using a systems perspective for postural control, an established framework for balance in pediatric populations. Components of balance evaluated in measures were underlying motor systems (100% of measures), anticipatory postural control (72%), static stability (62%), sensory integration (52%), dynamic stability (48%), functional stability limits (24%), cognitive influences (24%), verticality (9%), and reactive postural control (0%). Assessing children's balance with valid and comprehensive measures is important for ensuring development of safe mobility and independence with functional tasks. Balance measures validated in pediatric populations to date do not comprehensively assess standing postural control and omit some key components for safe mobility and independence. Existing balance measures, that have been validated in adult populations and address some of the existing gaps in pediatric measures, warrant consideration for validation in children. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A point of application study to determine the accuracy, precision and reliability of a low-cost balance plate for center of pressure measurement.

PubMed

Goble, Daniel J; Khan, Ehran; Baweja, Harsimran S; O'Connor, Shawn M

2018-04-11

Changes in postural sway measured via force plate center of pressure have been associated with many aspects of human motor ability. A previous study validated the accuracy and precision of a relatively new, low-cost and portable force plate called the Balance Tracking System (BTrackS). This work compared a laboratory-grade force plate versus BTrackS during human-like dynamic sway conditions generated by an inverted pendulum device. The present study sought to extend previous validation attempts for BTrackS using a more traditional point of application (POA) approach. Computer numerical control (CNC) guided application of ∼155 N of force was applied five times to each of 21 points on five different BTrackS Balance Plate (BBP) devices with a hex-nose plunger. Results showed excellent agreement (ICC > 0.999) between the POAs and measured COP by the BBP devices, as well as high accuracy (<1% average percent error) and precision (<0.1 cm average standard deviation of residuals). The ICC between BBP devices was exceptionally high (ICC > 0.999) providing evidence of almost perfect inter-device reliability. Taken together, these results provide an important, static corollary to the previously obtained dynamic COP results from inverted pendulum testing of the BBP. Copyright © 2018 Elsevier Ltd. All rights reserved.

Kung-fu versus swimming training and the effects on balance abilities in young adolescents.

PubMed

Baccouch, Rym; Rebai, Haithem; Sahli, Sonia

2015-11-01

Our purpose is to investigate the static balance control of young adolescents practicing kung-fu and swimming in order to find out which of these physical activities is the most effective in developing specific balance abilities in young adolescents. Comparative experimental study. University laboratory research. Three groups of 11-13-year-old boys (12 practicing Kung-Fu, 12 practicing swimming and 12 controls). Center of pressure (CoP) excursions were registered in upright bipedal and unipedal stances on a stabilometric force platform in eyes open (EO) and eyes closed (EC) conditions. Kung-fu practitioners control their balance (P < .05) better than controls and swimmers in the unipedal posture when visual inputs are available. Kung-fu training improved (P < .05) the bipedal balance control in the EO condition. However, swimming training developed (P < .05) bipedal balance control in both EO and EC conditions. The swimmers showed a lower reliance on vision (P < .05) compared to kung-fu practitioners. Both of these physical activities could be recommended for young adolescents as recreational or rehabilitation programs as they develop specific balance abilities that could be important for improving and maintaining optimal health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Do measures of reactive balance control predict falls in people with stroke returning to the community?

PubMed

Mansfield, A; Wong, J S; McIlroy, W E; Biasin, L; Brunton, K; Bayley, M; Inness, E L

2015-12-01

To determine if reactive balance control measures predict falls after discharge from stroke rehabilitation. Prospective cohort study. Rehabilitation hospital and community. Independently ambulatory individuals with stroke who were discharged home after inpatient rehabilitation (n=95). Balance and gait measures were obtained from a clinical assessment at discharge from inpatient stroke rehabilitation. Measures of reactive balance control were obtained: (1) during quiet standing; (2) when walking; and (3) in response to large postural perturbations. Participants reported falls and activity levels up to 6 months post-discharge. Logistic and Poisson regressions were used to identify measures of reactive balance control that were related to falls post-discharge. Decreased paretic limb contribution to standing balance control [rate ratio 0.8, 95% confidence interval (CI) 0.7 to 1.0; P=0.011], reduced between-limb synchronisation of quiet standing balance control (rate ratio 0.9, 95% CI 0.8 to 0.9; P<0.0001), increased step length variability (rate ratio 1.4, 95% CI 1.2 to 1.7; P=0.0011) and inability to step with the blocked limb (rate ratio 1.2, 95% CI 1.0 to 1.3; P=0.013) were significantly associated with increased fall rates when controlling for age, stroke severity, functional balance and daily walking activity. Impaired reactive balance control in standing and walking predicted increased risk of falls post-discharge from stroke rehabilitation. Specifically, measures that revealed the capacity of both limbs to respond to instability were related to increased risk of falls. These results suggest that post-stroke rehabilitation strategies for falls prevention should train responses to instability, and focus on remediating dyscontrol in the more-affected limb. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Control Chart on Semi Analytical Weighting

NASA Astrophysics Data System (ADS)

Miranda, G. S.; Oliveira, C. C.; Silva, T. B. S. C.; Stellato, T. B.; Monteiro, L. R.; Marques, J. R.; Faustino, M. G.; Soares, S. M. V.; Ulrich, J. C.; Pires, M. A. F.; Cotrim, M. E. B.

2018-03-01

Semi-analytical balance verification intends to assess the balance performance using graphs that illustrate measurement dispersion, trough time, and to demonstrate measurements were performed in a reliable manner. This study presents internal quality control of a semi-analytical balance (GEHAKA BG400) using control charts. From 2013 to 2016, 2 weight standards were monitored before any balance operation. This work intended to evaluate if any significant difference or bias were presented on weighting procedure over time, to check the generated data reliability. This work also exemplifies how control intervals are established.

Development of Static Balance Measurement and Correction Compound Platform for Single Blade of Controllable Pitch Propeller

NASA Astrophysics Data System (ADS)

Chao, Zhang; Shijie, Su; Yilin, Yang; Guofu, Wang; Chao, Wang

2017-11-01

Aiming at the static balance of the controllable pitch propeller (CPP), a high efficiency static balance method based on the double-layer structure of the measuring table and gantry robot is adopted to realize the integration of torque measurement and corrected polish for controllable pitch propeller blade. The control system was developed by Microsoft Visual Studio 2015, and a composite platform prototype was developed. Through this prototype, conduct an experiment on the complete process of torque measurement and corrected polish based on a 300kg class controllable pitch propeller blade. The results show that the composite platform can correct the static balance of blade with a correct, efficient and labor-saving operation, and can replace the traditional method on static balance of the blade.

Social Bots: Human-Like by Means of Human Control?

PubMed

Grimme, Christian; Preuss, Mike; Adam, Lena; Trautmann, Heike

2017-12-01

Social bots are currently regarded an influential but also somewhat mysterious factor in public discourse and opinion making. They are considered to be capable of massively distributing propaganda in social and online media, and their application is even suspected to be partly responsible for recent election results. Astonishingly, the term social bot is not well defined and different scientific disciplines use divergent definitions. This work starts with a balanced definition attempt, before providing an overview of how social bots actually work (taking the example of Twitter) and what their current technical limitations are. Despite recent research progress in Deep Learning and Big Data, there are many activities bots cannot handle well. We then discuss how bot capabilities can be extended and controlled by integrating humans into the process and reason that this is currently the most promising way to realize meaningful interactions with other humans. This finally leads to the conclusion that hybridization is a challenge for current detection mechanisms and has to be handled with more sophisticated approaches to identify political propaganda distributed with social bots.

The effect of Meibomian lipids and tear proteins on evaporation rate under controlled in vitro conditions.

PubMed

Herok, George Henryk; Mudgil, Poonam; Millar, Thomas James

2009-07-01

The lipid layer of the tear film is associated with preventing evaporative loss. The ability of human Meibomian lipids to reduce evaporation in vitro was tested. Films of human or animal Meibomian lipids or mixtures of cholesterol and phosphatidylcholine were spread on the surface of either artificial buffer or on whole tears and placed on a mass balance that was enclosed in a sealed chamber. The temperature was adjusted to 37 degrees C and gas flow was controlled. Increasing the amounts of Meibomian lipids gave a very small reduction in evaporation. It was concluded from these in vitro experiments that prevention of evaporation from the tear film is not due to the Meibomian lipids alone, but is more likely to be due to a complex interaction between components of the aqueous and the Meibomian lipids.

The occupational safety and health scorecard--a business case example for strategic management.

PubMed

Köper, Birgit; Möller, Klaus; Zwetsloot, Gerard

2009-12-01

Human resources and health issues are crucial in terms of corporate competitiveness. However, systematic, continuous and strategically aligned occupational safety and health (OSH) management is scarcely applied in companies. One major reason for this could be the lack of generally accepted and standardised OSH control methods. Our objective was thus to conceptualize a method by which qualitative factors such as human resources and OSH aspects contribute to the performance or value-added layer of an organization. We developed a business case based on the well-known and accepted Balanced Scorecard approach, which we adapted and applied to the management of OSH issues. The concept was implemented in the course of a comprehensive case study at a German automobile manufacturer. We gathered health as well as finance data in order to test which health-related indicators had an impact on financial performance. The demonstration of, and reporting on, how the promotion of workplace health contributes strategically to the organization is crucial for both health and human resource managers. Based on multivariate regression analyses, our main finding was that the Balanced Scorecard approach is an adequate means to control OSH issues in terms of strategic health management. Our analyses demonstrated that health-related interventions contribute significantly to performance aspects such as quality, productivity, absenteeism, and cost reduction. Therefore, the financial impact of health-related aspects / interventions could be demonstrated by means of the OSH scorecard. The availability and quality of health data within the context of overall corporate performance data needs to be improved in order to bridge OSH-related and performance issues of an organization.

[Balance trainability using the Nintendo Wii balance board in sportive people].

PubMed

Paukowits, S; Stöggl, T

2014-03-01

A multivariable training has a positive impact on balance skills and risk of injury. To date the effect of this training using the Nintendo Wii balance board in sportive people has not yet been investigated. The aim of this study was to investigate whether training with the Nintendo Wii balance board can improve balance skills. 20 people were randomized into a control and an intervention group each with 10 people who performed a unilateral stance test with eyes open and closed as well as the star excursion balance test before and after the intervention. The control group completed their usual sports and the intervention group an adjunct training with the Nintendo Wii balance board for 4 weeks. Adjunct Training using the Nintendo Wii Balance Board did not improve sportive people's balance skills significantly. The intervention group, however, attained better results in the star excursion balance test, whereas the control group did not show any changes. The unilateral stance tests did not provide significant differences before and after training within both groups. The use of the Nintendo Wii balance board should be further investigated by employing individual difficulty levels. © Georg Thieme Verlag KG Stuttgart · New York.

To be, or not to be obese - that's the challenge: a hypothesis on the cortical inhibition of the hypothalamus and its therapeutical consequences.

PubMed

Kreier, Felix

2010-08-01

Today, obesity is the most urgent unsolved medical problem, with the threat of a decreased life expectancy rate for the first time in medical history. Many obese subjects try to lose weight by dieting and exercising, without success on a long term basis. The only therapy with some effect is bariatric surgery with the impact of sustainable adverse effects only suitable in morbid obesity. Why are the therapies to treat obesity not working? Within the last years, we have become more aware of the role of the brain in energy homeostasis. The three main players within the brain controlling our weight are the cortex for cognition, hypothalamus for vital body functions and limbic-reward system for emotions. One hypothesizes that the failure of the cortex to inhibit the hypothalamus is the main cause of obesity. The evolutionary old hypothalamus constantly seeks for a positive energy balance, always in endeavor to avoid any energy shortage in the future. The hypothalamus is executing its tasks in a parallel mode. It can coordinate a set of vital routines independently, yet simultaneously. For e.g., energy balance, salt balance, body temperature and sleep are executed even in a coma. The hypothalamus is primitive but stable. The cortex in humans is, compared to rodents, much bigger and more complex, while the hypothalamus bears more similarities between these two species. The cortex in humans is evolutionary younger and represents higher cognition, an unique human feature. In contrast to the hypothalamus, the cortex focuses on one problem at a time, thus functioning on an attention-based manner. Due to this serial mode, the cortex uses a large part of its capacity for one problem at a time. Therefore, it can solve more complex calculations than the hypothalamus by thinking about one problem after another. It is even strong enough to veto the hypothalamus, if necessary. If the concentration on weight loss is distorted, the hypothalamus is free of inhibition by the cortex, and the subject will gain weight again. It is suggested that this is why diets do not work in the long term. In anorexic patients, the cortex is fully occupied to control the hypothalamus resulting in extreme weight loss. In obese subjects, the cortex is less disciplined and the hypothalamus will take control again to stimulate positive energy balance. From this viewpoint, the limbic-reward system interacts both with the hypothalamus and the cortex to achieve demands by emotional motivation. The last part of this paper describes a therapeutic strategy based on this hypothesis. We propose a dual approach to fight obesity. First, interventions should be implemented that remind the cortex to control the hypothalamus and second, to stimulate physiological feedback to the hypothalamus. Copyright 2010 Elsevier Ltd. All rights reserved.

Efficacy of ankle control balance training on postural balance and gait ability in community-dwelling older adults: a single-blinded, randomized clinical trial.

PubMed

Lee, Kyeongjin; Lee, Yong Woo

2017-09-01

[Purpose] This study was conducted to investigate the effects of ankle control balance training (ACBT) on postural balance and gait ability in community-dwelling older adults. [Subjects and Methods] Fifty-four subjects were randomly divided into two groups, with 27 subjects in the ACBT group and 27 subjects in the control group. Subjects in the ACBT group received ACBT for 60 minutes, twice per week for 4 weeks, and all subjects had undergone fall prevention education for 60 minutes, once per week for 4 weeks. The main outcome measures, including the Berg balance scale; the functional reach test and one leg stance test for postural balance; and the timed up-and-go test and 10-meter walking test for gait ability, were assessed at baseline and after 4 weeks of training. [Results] The postural balance and gait ability in the ACBT group improved significantly compared to those in the control group, except BBS. [Conclusion] The results of this study showed improved postural balance and gait abilities after ACBT and that ACBT is a feasible method for improving postural balance and gait ability in community-dwelling older adults.

Efficacy of ankle control balance training on postural balance and gait ability in community-dwelling older adults: a single-blinded, randomized clinical trial

PubMed Central

Lee, Kyeongjin; Lee, Yong Woo

2017-01-01

[Purpose] This study was conducted to investigate the effects of ankle control balance training (ACBT) on postural balance and gait ability in community-dwelling older adults. [Subjects and Methods] Fifty-four subjects were randomly divided into two groups, with 27 subjects in the ACBT group and 27 subjects in the control group. Subjects in the ACBT group received ACBT for 60 minutes, twice per week for 4 weeks, and all subjects had undergone fall prevention education for 60 minutes, once per week for 4 weeks. The main outcome measures, including the Berg balance scale; the functional reach test and one leg stance test for postural balance; and the timed up-and-go test and 10-meter walking test for gait ability, were assessed at baseline and after 4 weeks of training. [Results] The postural balance and gait ability in the ACBT group improved significantly compared to those in the control group, except BBS. [Conclusion] The results of this study showed improved postural balance and gait abilities after ACBT and that ACBT is a feasible method for improving postural balance and gait ability in community-dwelling older adults. PMID:28931994

Visual Biofeedback Balance Training Using Wii Fit after Stroke: A Randomized Controlled Trial

PubMed Central

Barcala, Luciana; Grecco, Luanda André Collange; Colella, Fernanda; Lucareli, Paulo Roberto Garcia; Salgado, Afonso Shiguemi Inoue; Oliveira, Claudia Santos

2013-01-01

[Purpose] The aim of the present study was to investigate the effect of balance training with visual biofeedback on balance, body symmetry, and function among individuals with hemiplegia following a stroke. [Subjects and Methods] The present study was performed using a randomized controlled clinical trial with a blinded evaluator. The subjects were twenty adults with hemiplegia following a stroke. The experimental group performed balance training with visual biofeedback using Wii Fit® together with conventional physical therapy. The control group underwent conventional physical therapy alone. The intervention lasted five weeks, with two sessions per week. Body symmetry (baropodometry), static balance (stabilometry), functional balance (Berg Balance Scale), functional mobility (Timed Up and Go test), and independence in activities of daily living (Functional Independence Measure) were assessed before and after the intervention. [Results] No statistically significant differences were found between the experimental and control groups. In the intragroup analysis, both groups demonstrated a significant improvement in all variables studied. [Conclusion] The physical therapy program combined with balance training involving visual biofeedback (Wii Fit®) led to an improvement in body symmetry, balance, and function among stroke victims. However, the improvement was similar to that achieved with conventional physical therapy alone. PMID:24259909

Systematic review of postural control and lateral ankle instability, part II: is balance training clinically effective?

PubMed

McKeon, Patrick O; Hertel, Jay

2008-01-01

To answer the following clinical questions: (1) Can prophylactic balance and coordination training reduce the risk of sustaining a lateral ankle sprain? (2) Can balance and coordination training improve treatment outcomes associated with acute ankle sprains? (3) Can balance and coordination training improve treatment outcomes in patients with chronic ankle instability? PubMed and CINAHL entries from 1966 through October 2006 were searched using the terms ankle sprain, ankle instability, balance, chronic ankle instability, functional ankle instability, postural control, and postural sway. Only studies assessing the influence of balance training on the primary outcomes of risk of ankle sprain or instrumented postural control measures derived from testing on a stable force plate using the modified Romberg test were included. Studies had to provide results for calculation of relative risk reduction and numbers needed to treat for the injury prevention outcomes or effect sizes for the postural control measures. We calculated the relative risk reduction and numbers needed to treat to assess the effect of balance training on the risk of incurring an ankle sprain. Effect sizes were estimated with the Cohen d for comparisons of postural control performance between trained and untrained groups. Prophylactic balance training substantially reduced the risk of sustaining ankle sprains, with a greater effect seen in those with a history of a previous sprain. Completing at least 6 weeks of balance training after an acute ankle sprain substantially reduced the risk of recurrent ankle sprains; however, consistent improvements in instrumented measures of postural control were not associated with training. Evidence is lacking to assess the reduction in the risk of recurrent sprains and inconclusive to demonstrate improved instrumented postural control measures in those with chronic ankle instability who complete balance training. Balance training can be used prophylactically or after an acute ankle sprain in an effort to reduce future ankle sprains, but current evidence is insufficient to assess this effect in patients with chronic ankle instability.

The Influence of Task Difficulty and Participant Age on Balance Control in ASD

ERIC Educational Resources Information Center

Graham, Sarah A.; Abbott, Angela E.; Nair, Aarti; Lincoln, Alan J.; Müller, Ralph-Axel; Goble, Daniel J.

2015-01-01

Impairments in sensorimotor integration are reported in Autism Spectrum Disorder (ASD). Poor control of balance in challenging balance tasks is one suggested manifestation of these impairments, and is potentially related to ASD symptom severity. Reported balance and symptom severity relationships disregard age as a potential covariate, however,…

Cortical NMDA receptor expression in human chronic alcoholism: influence of the TaqIA allele of ANKK1.

PubMed

Ridge, Justin P; Dodd, Peter R

2009-10-01

Real-time RT-PCR normalized to GAPDH was used to assay N-methyl-D-aspartate (NMDA) receptor NR1, NR2A and NR2B subunit mRNA in human autopsy cortex tissue from chronic alcoholics with and without comorbid cirrhosis of the liver and matched controls. Subunit expression was influenced by the subject's genotype. The TaqIA polymorphism selectively modulated NMDA receptor mean transcript expression in cirrhotic-alcoholic superior frontal cortex, in diametrically opposite ways in male and female subjects. Genetic make-up may differentially influence vulnerability to brain damage by altering the excitation: inhibition balance, particularly in alcoholics with comorbid cirrhosis of the liver. The TaqIA polymorphism occurs within the poorly characterised ankyrin-repeat containing kinase 1 (ANKK1) gene. Using PCR, ANKK1 mRNA transcript was detected in inferior temporal, occipital, superior frontal and primary motor cortex of control human brain. ANKK1 expression may mediate the influence of the TaqIA polymorphism on phenotype.

Eating patterns, diet quality and energy balance: from the macro- to the microscopic.

PubMed

Lowe, Michael R

2014-07-01

As a discussant for the 2013 IBRC Symposium on Eating Patterns, Diet Quality and Energy Balance at Purdue University, I describe here several reflections I had on the papers as a whole. I initially focus on the keynote address by Dr. Leonard. His address suggested that the evolutionary development of Homo sapiens during the past 2 million years may have "prepared" humans to seek and consume food beyond their immediate energy needs, a predisposition that may have rendered humans particularly vulnerable to modern food environments. Additional observations include: 1) the importance of differentiating between a given appetitive variable (e.g., snacking) as a potential cause versus consequence of an outcome of interest (e.g., obesity), 2) the need to move beyond research on the consummatory phase of appetite to the anticipatory phase of appetite, and 3) the opportunity that exists to take the many obesogenic nutritional influences documented in the symposium and "turn them on their heads" to facilitate, rather than undermine, long-term weight control. Copyright © 2014 Elsevier Inc. All rights reserved.

A Model-Based Approach for Identifying Signatures of Ancient Balancing Selection in Genetic Data

PubMed Central

DeGiorgio, Michael; Lohmueller, Kirk E.; Nielsen, Rasmus

2014-01-01

While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates. PMID:25144706

A model-based approach for identifying signatures of ancient balancing selection in genetic data.

PubMed

DeGiorgio, Michael; Lohmueller, Kirk E; Nielsen, Rasmus

2014-08-01

While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates.

Improvements in balance control in individuals with PCS detected following vestibular training: A case study.

PubMed

Prangley, Alyssa; Aggerholm, Mathew; Cinelli, Michael

2017-10-01

Concussed individuals have been found to experience balance deficits in the anterior-posterior (AP) direction as indicated by greater Center of Pressure (COP) displacement and velocity. One possible reason for this change in balance control could be due to damage to the lateral vestibulospinal tract which sends signals to control posterior muscles, specifically ankle extensors leading to compensatory torques about the ankle. The purpose of the study was to quantify balance assessments in individuals experiencing persistent post-concussion symptoms (PCS) to determine balance control changes following a vestibular training intervention. Participants (N=6,>26days symptomatic), were tested during their first appointment with a registered physiotherapist (PT) and during each follow up appointment. Participants were prescribed balance, visual, and neck strengthening exercises by the PT that were to be completed daily between bi-weekly appointments. Balance assessments were quantified using a Nintendo Wii board to record ground reaction forces. Participants completed 4 balance assessments: 1) Romberg stance eyes open (REO); 2) Romberg stance eyes closed (REC); 3) single leg stance eyes open (SEO); and 4) single leg stance eyes closed (SEC). The balance assessments were conducted on both a firm and compliant surfaces. Significant improvements in balance control were noted in ML/AP displacement and velocity of COP for both SEC and Foam REC conditions, with additional improvements in AP velocity of COP for Foam REC and in ML displacement of COP during Foam SEC. Overall, findings indicate that objectively quantifying balance changes for individuals experiencing persistent PCS allows for a more sensitive measure of balance and detects changes unrecognizable to the naked eye. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of Wii-intervention on balance of children with poor motor performance.

PubMed

Mombarg, Remo; Jelsma, Dorothee; Hartman, Esther

2013-09-01

The purpose of this study was to investigate the effects of training with the Wii-balance board on balance and balance-related skills of children with poor motor performance. Twenty-nine children (23 boys, 6 girls; aged 7-12 years) participated in this study and were randomly assigned to an experimental and control group. All children scored below the 16th percentile on a standardized test of motor ability and balance skills (Movement Assessment Battery for children (M-ABC-2)). Before and after a six-week Wii-intervention (M=8h, 22 min, SD=53 min), the balance skills of the experimental group and control group were measured with the M-ABC-2 and the Bruininks-Oseretsky test of motor proficiency (BOT-2). Both groups improved on all tests. The M-ABC-2 and the BOT-2 total balance-scores of the experimental group improved significantly from pre to post intervention, whereas those of the control group showed no significant progress. This resulted in significant interaction-effects, favoring the experimental children. No transfer-effects of the intervention on balance-related skills were demonstrated. Our findings showed that the Wii-balance board is an effective intervention for children with poor balance control. Further development and investigation of the intervention could be directed toward the implementation of the newly acquired balance-skills in daily life. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Automated Assessment of Postural Stability: Balance Detection Algorithm.

PubMed

Napoli, Alessandro; Glass, Stephen M; Tucker, Carole; Obeid, Iyad

2017-12-01

Impaired balance is a common indicator of mild traumatic brain injury, concussion and musculoskeletal injury. Given the clinical relevance of such injuries, especially in military settings, it is paramount to develop more accurate and reliable on-field evaluation tools. This work presents the design and implementation of the automated assessment of postural stability (AAPS) system, for on-field evaluations following concussion. The AAPS is a computer system, based on inexpensive off-the-shelf components and custom software, that aims to automatically and reliably evaluate balance deficits, by replicating a known on-field clinical test, namely, the Balance Error Scoring System (BESS). The AAPS main innovation is its balance error detection algorithm that has been designed to acquire data from a Microsoft Kinect ® sensor and convert them into clinically-relevant BESS scores, using the same detection criteria defined by the original BESS test. In order to assess the AAPS balance evaluation capability, a total of 15 healthy subjects (7 male, 8 female) were required to perform the BESS test, while simultaneously being tracked by a Kinect 2.0 sensor and a professional-grade motion capture system (Qualisys AB, Gothenburg, Sweden). High definition videos with BESS trials were scored off-line by three experienced observers for reference scores. AAPS performance was assessed by comparing the AAPS automated scores to those derived by three experienced observers. Our results show that the AAPS error detection algorithm presented here can accurately and precisely detect balance deficits with performance levels that are comparable to those of experienced medical personnel. Specifically, agreement levels between the AAPS algorithm and the human average BESS scores ranging between 87.9% (single-leg on foam) and 99.8% (double-leg on firm ground) were detected. Moreover, statistically significant differences in balance scores were not detected by an ANOVA test with alpha equal to 0.05. Despite some level of disagreement between human and AAPS-generated scores, the use of an automated system yields important advantages over currently available human-based alternatives. These results underscore the value of using the AAPS, that can be quickly deployed in the field and/or in outdoor settings with minimal set-up time. Finally, the AAPS can record multiple error types and their time course with extremely high temporal resolution. These features are not achievable by humans, who cannot keep track of multiple balance errors with such a high resolution. Together, these results suggest that computerized BESS calculation may provide more accurate and consistent measures of balance than those derived from human experts.

Comparison of digital controllers used in magnetic suspension and balance systems

NASA Technical Reports Server (NTRS)

Kilgore, William A.

1990-01-01

Dynamic systems that were once controlled by analog circuits are now controlled by digital computers. Presented is a comparison of the digital controllers presently used with magnetic suspension and balance systems. The overall responses of the systems are compared using a computer simulation of the magnetic suspension and balance system and the digital controllers. The comparisons include responses to both simulated force and position inputs. A preferred digital controller is determined from the simulated responses.

Work-based resources as moderators of the relationship between work hours and satisfaction with work-family balance.

PubMed

Valcour, Monique

2007-11-01

This study reports an investigation of the relationships of work hours, job complexity, and control over work time to satisfaction with work-family balance. Based on data from a sample of 570 telephone call center representatives, a moderated hierarchical regression analysis revealed that work hours were negatively related to satisfaction with work-family balance, consistent with the resource drain perspective. Job complexity and control over work time were positively associated with satisfaction with work-family balance. Control over work time moderated the relationship such that as work hours rose, workers with low control experienced a decline in work-family balance satisfaction, while workers with high control did not. Results encourage greater research attention to work characteristics, such as job complexity and control over work time, and skills that represent resources useful to the successful integration of work and family demands. (c) 2007 APA

Effects of a 12-week Tai Chi Chuan program versus a balance training program on postural control and walking ability in older people.

PubMed

Lelard, Thierry; Doutrellot, Pierre-Louis; David, Pascal; Ahmaidi, Said

2010-01-01

Lelard T, Doutrellot P-L, David P, Ahmaidi S. Effects of a 12-week Tai Chi Chuan program versus a balance training program on postural control and walking ability in older people. To compare the respective effects of 2 balance training programs: a Tai Chi (TC) program and a balance training program on static postural control and walking ability. Randomized controlled trial. General community. Older subjects (N=28) participated in the study. The TC group (n=14; mean age +/- SD, 76.8+/-5.1y) and the balance training group (n=14; 77.0+/-4.5y) were both trained for 12 weeks. Static postural control was assessed via measurement of center of pressure sway under eyes open (EO) and eyes closed (EC) conditions. Walking speed over a 10-meter course was also assessed. After the 12-week training period, there were no significant differences in walking speed or postural parameters in either the EO or EC conditions for the TC and balance training groups. Performance in the EC condition was lower than in the EO condition in pretest and posttest for the balance training and TC groups. The Romberg quotient (EO/EC ratio) was significantly higher after the balance training program than the TC program (P<.05). We cannot conclude that the balance training program has better effects than the TC program on postural control or walking ability. None of the outcome measures showed significant change posttraining in either the TC or the balance training groups. However, the differences described in the Romberg quotient after the training period between the TC and the balance training groups suggest that TC should be helpful to limit the deleterious effects of eye closure on postural balance. Copyright (c) 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Effects of Muscle Strength and Balance Control on Sit-to-Walk and Turn Durations in the Timed Up and Go Test.

PubMed

Chen, Tzurei; Chou, Li-Shan

2017-12-01

To examine the association of muscle strength and balance control with the amount of time taken to perform sit-to-walk (STW) or turning components of the Timed Up and Go (TUG) test in older adults. Correlations; multiple regression models. General community. Older adults (N=60) age >70 years recruited from the community. Not applicable. Muscle strength, balance control, and TUG test performance time. Muscle strength was quantified by peak joint moments during the isometric maximal voluntary contraction test for bilateral hip abductors, knee extensors, and ankle plantar flexors. Balance control was assessed with the Berg Balance Scale, Fullerton Advanced Balance Scale, and center of mass and ankle inclination angle derived during the TUG test performance. We found that balance control measures were significantly associated with both STW and turning durations even after controlling for muscle strength and other confounders (STW duration: P<.001, turning duration: P=.001). Adding strength to the regression model was found to significantly improve its prediction of STW duration (F change =5.945, P=.018), but not turning duration (F change =1.03, P=.14). Our findings suggest that poor balance control is an important factor that contributes to longer STW and turning durations on the TUG test. Furthermore, strength has a higher association with STW than turning duration. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Adaptive Vibration Reduction Controls for a Cryocooler With a Passive Balancer

NASA Technical Reports Server (NTRS)

Kopasakis, George; Cairelli, James E.; Traylor, Ryan M.

2001-01-01

In this paper an adaptive vibration reduction control (AVRC) design is described for a Stirling cryocooler combined with a passive balancer. The AVRC design was based on a mass-spring model of the cooler and balancer, and the AVRC algorithm described in this paper was based on an adaptive binary search. Results are shown comparing the baseline uncontrolled cooler with no balancer, the cooler with the balancer, and, finally, the cooler with the balancer and the AVRC. The comparison shows that it may be possible to meet stringent vibration reduction requirements without an active balancer.

Effects of Nintendo Wii-Fit® video games on balance in children with mild cerebral palsy.

PubMed

Tarakci, Devrim; Ersoz Huseyinsinoglu, Burcu; Tarakci, Ela; Razak Ozdincler, Arzu

2016-10-01

This study compared the effects of Nintendo Wii-Fit ® balance-based video games and conventional balance training in children with mild cerebral palsy (CP). This randomized controlled trial involved 30 ambulatory pediatric patients (aged 5-18 years) with CP. Participants were randomized to either conventional balance training (control group) or to Wii-Fit balance-based video games training (Wii group). Both group received neuro-developmental treatment (NDT) during 24 sessions. In addition, while the control group received conventional balance training in each session, the Wii group played Nintendo Wii Fit games such as ski slalom, tightrope walk and soccer heading on balance board. Primary outcomes were Functional Reach Test (forward and sideways), Sit-to-Stand Test and Timed Get up and Go Test. Nintendo Wii Fit balance, age and game scores, 10 m walk test, 10-step climbing test and Wee-Functional Independence Measure (Wee FIM) were secondary outcomes. After the treatment, changes in balance scores and independence level in activities of daily living were significant (P < 0.05) in both groups. Statistically significant improvements were found in the Wii-based game group compared with the control group in all balance tests and total Wee FIM score (P < 0.05). Wii-fit balance-based video games are better at improving both static and performance-related balance parameters when combined with NDT treatment in children with mild CP. © 2016 Japan Pediatric Society.

A Balanced Risk-Benefit Analysis to Determine Human Risks Associated with Pyrrolizidine Alkaloids (PA)-The Case of Tea and Herbal Infusions.

PubMed

Habs, Michael; Binder, Karin; Krauss, Stefan; Müller, Karolina; Ernst, Brigitte; Valentini, Luzia; Koller, Michael

2017-07-07

Humans are exposed to pyrrolizidine alkaloids (PA) through different sources, mainly from contaminated foodstuff. Teas and herbal infusions (T&HI) can be contaminated by PA producing weed. PA can possess toxic, mutagenic, genotoxic, and carcinogenic properties. Thus, possible health risks for the general population are under debate. There is a strong safety record for T&HI and additionally epidemiological evidence for the preventive effects of regular tea consumption on cardiovascular events and certain types of cancer. There is no epidemiological evidence, however, for human risks of regular low dose PA exposure. Recommended regulatory PA-threshold values are based on experimental data only, accepting big uncertainties. If a general risk exists through PA contaminated T&HI, it must be small compared to other frequently accepted risks of daily living and the proven health effects of T&HI. Decision making should be based on a balanced riskbenefit analysis. Based on analyses of the scientific data currently available, it is concluded that the benefits of drinking T&HI clearly outweigh the negligible health risk of possible PA contamination. At the same time, manufacturers must continue their efforts to secure good product quality and to be transparent on their measures of quality control and risk communication.

Emulating Host-Microbiome Ecosystem of Human Gastrointestinal Tract in Vitro.

PubMed

Park, Gun-Seok; Park, Min Hee; Shin, Woojung; Zhao, Connie; Sheikh, Sameer; Oh, So Jung; Kim, Hyun Jung

2017-06-01

The human gut microbiome performs prodigious physiological functions such as production of microbial metabolites, modulation of nutrient digestion and drug metabolism, control of immune system, and prevention of infection. Paradoxically, gut microbiome can also negatively orchestrate the host responses in diseases or chronic disorders, suggesting that the regulated and balanced host-gut microbiome crosstalk is a salient prerequisite in gastrointestinal physiology. To understand the pathophysiological role of host-microbiome crosstalk, it is critical to recreate in vivo relevant models of the host-gut microbiome ecosystem in human. However, controlling the multi-species microbial communities and their uncontrolled growth has remained a notable technical challenge. Furthermore, conventional two-dimensional (2D) or 3D culture systems do not recapitulate multicellular microarchitectures, mechanical dynamics, and tissue-specific functions. Here, we review recent advances and current pitfalls of in vitro and ex vivo models that display human GI functions. We also discuss how the disruptive technologies such as 3D organoids or a human organ-on-a-chip microphysiological system can contribute to better emulate host-gut microbiome crosstalks in health and disease. Finally, the medical and pharmaceutical significance of the gut microbiome-based personalized interventions is underlined as a future perspective.

Comparative Effects of Different Balance-Training–Progression Styles on Postural Control and Ankle Force Production: A Randomized Controlled Trial

PubMed Central

Cuğ, Mutlu; Duncan, Ashley; Wikstrom, Erik

2016-01-01

Context:  Despite the effectiveness of balance training, the exact parameters needed to maximize the benefits of such programs remain unknown. One such factor is how individuals should progress to higher levels of task difficulty within a balance-training program. Yet no investigators have directly compared different balance-training–progression styles. Objective:  To compare an error-based progression (ie, advance when proficient at a task) with a repetition-based progression (ie, advance after a set amount of repetitions) style during a balance-training program in healthy individuals. Design:  Randomized controlled trial. Setting:  Research laboratory. Patients or Other Participants:  A total of 28 (16 women, 12 men) physically healthy young adults (age = 21.57 ± 3.95 years, height = 171.60 ± 11.03 cm, weight = 72.96 ± 16.18 kg, body mass index = 24.53 ± 3.7). Intervention(s):  All participants completed 12 supervised balance-training sessions over 4 weeks. Each session consisted of a combination of dynamic unstable-surface tasks that incorporated a BOSU ball and lasted about 30 minutes. Main Outcome Measure(s):  Static balance from an instrumented force plate, dynamic balance as measured via the Star Excursion Balance Test, and ankle force production in all 4 cardinal planes of motion as measured with a handheld dynamometer before and after the intervention. Results:  Selected static postural-control outcomes, dynamic postural control, and ankle force production in all planes of motion improved (P < .05). However, no differences between the progression styles were observed (P > .05) for any of the outcome measures. Conclusions:  A 4-week balance-training program consisting of dynamic unstable-surface exercises on a BOSU ball improved dynamic postural control and ankle force production in healthy young adults. These results suggest that an error-based balance-training program is comparable with but not superior to a repetition-based balance-training program in improving postural control and ankle force production in healthy young adults. PMID:26878257

Associations between Proprioceptive Neural Pathway Structural Connectivity and Balance in People with Multiple Sclerosis

PubMed Central

Fling, Brett W.; Dutta, Geetanjali Gera; Schlueter, Heather; Cameron, Michelle H.; Horak, Fay B.

2014-01-01

Mobility and balance impairments are a hallmark of multiple sclerosis (MS), affecting nearly half of patients at presentation and resulting in decreased activity and participation, falls, injuries, and reduced quality of life. A growing body of work suggests that balance impairments in people with mild MS are primarily the result of deficits in proprioception, the ability to determine body position in space in the absence of vision. A better understanding of the pathophysiology of balance disturbances in MS is needed to develop evidence-based rehabilitation approaches. The purpose of the current study was to (1) map the cortical proprioceptive pathway in vivo using diffusion-weighted imaging and (2) assess associations between proprioceptive pathway white matter microstructural integrity and performance on clinical and behavioral balance tasks. We hypothesized that people with MS (PwMS) would have reduced integrity of cerebral proprioceptive pathways, and that reduced white matter microstructure within these tracts would be strongly related to proprioceptive-based balance deficits. We found poorer balance control on proprioceptive-based tasks and reduced white matter microstructural integrity of the cortical proprioceptive tracts in PwMS compared with age-matched healthy controls (HC). Microstructural integrity of this pathway in the right hemisphere was also strongly associated with proprioceptive-based balance control in PwMS and controls. Conversely, while white matter integrity of the right hemisphere’s proprioceptive pathway was significantly correlated with overall balance performance in HC, there was no such relationship in PwMS. These results augment existing literature suggesting that balance control in PwMS may become more dependent upon (1) cerebellar-regulated proprioceptive control, (2) the vestibular system, and/or (3) the visual system. PMID:25368564

Associations between Proprioceptive Neural Pathway Structural Connectivity and Balance in People with Multiple Sclerosis.

PubMed

Fling, Brett W; Dutta, Geetanjali Gera; Schlueter, Heather; Cameron, Michelle H; Horak, Fay B

2014-01-01

Mobility and balance impairments are a hallmark of multiple sclerosis (MS), affecting nearly half of patients at presentation and resulting in decreased activity and participation, falls, injuries, and reduced quality of life. A growing body of work suggests that balance impairments in people with mild MS are primarily the result of deficits in proprioception, the ability to determine body position in space in the absence of vision. A better understanding of the pathophysiology of balance disturbances in MS is needed to develop evidence-based rehabilitation approaches. The purpose of the current study was to (1) map the cortical proprioceptive pathway in vivo using diffusion-weighted imaging and (2) assess associations between proprioceptive pathway white matter microstructural integrity and performance on clinical and behavioral balance tasks. We hypothesized that people with MS (PwMS) would have reduced integrity of cerebral proprioceptive pathways, and that reduced white matter microstructure within these tracts would be strongly related to proprioceptive-based balance deficits. We found poorer balance control on proprioceptive-based tasks and reduced white matter microstructural integrity of the cortical proprioceptive tracts in PwMS compared with age-matched healthy controls (HC). Microstructural integrity of this pathway in the right hemisphere was also strongly associated with proprioceptive-based balance control in PwMS and controls. Conversely, while white matter integrity of the right hemisphere's proprioceptive pathway was significantly correlated with overall balance performance in HC, there was no such relationship in PwMS. These results augment existing literature suggesting that balance control in PwMS may become more dependent upon (1) cerebellar-regulated proprioceptive control, (2) the vestibular system, and/or (3) the visual system.

Balance versus resistance training on postural control in patients with Parkinson's disease: a randomized controlled trial.

PubMed

Santos, Suhaila M; da Silva, Rubens A; Terra, Marcelle B; Almeida, Isabela A; de Melo, Lúcio B; Ferraz, Henrique B

2017-04-01

Evidences have shown that physiotherapy programs may improve the balance of individuals with Parkinson's disease (PD), although it is not clear which specific exercise program is better. The aim of this study was to compare the effectiveness of balance versus resistance training on postural control measures in PD patients. Randomized controlled trial. The study was conducted in a physiotherapy outpatient clinic of a university hospital. A total of 40 PD participants were randomly divided into two groups: balance training (BT) and resistance training (RT). The BT group focused on balance training, functional independence and gait while the RT group performed resistance exercises emphasizing the lower limbs and trunk, both supervised by trained physiotherapists. Therapy sessions were held twice a week (at 60 minutes), totaling 24 sessions. The primary outcome was evaluated by force platform with center of pressure sway measures in different balance conditions and the secondary outcome was evaluated by Balance Evaluation Systems Test (BESTest) scale to determine the effects of the intervention on postural control. Significant improvement of postural control (pre vs. post 15.1 vs. 9.6 cm2) was only reported in favor of BT group (d=1.17) for one-legged stand condition on force platform. The standardized mean difference between groups was significantly (P<0.02), with 36% of improvement for BT vs. 0.07% for RT on this condition. Significant improvement (P<0.05) was also observed in favor of BT (in mean 3.2%) for balance gains in some BESTest scores, when compared to RT group (-0.98%). Postural control in Parkinson's disease is improved when training by a directional and specific balance program than a resistance training program. Balance training is superior to resistance training in regard to improving postural control of individuals with PD. Gold standard instruments (high in cost and difficult to access) were used to assess balance, as well as scales with clinical applicability (low cost, easily acceptable, applicable and valid), which can guide the management of physiotherapists both in their decision-making and in clinical practice.

The effects of moderate fatigue on dynamic balance control and attentional demands.

PubMed

Simoneau, Martin; Bégin, François; Teasdale, Normand

2006-09-28

During daily activities, the active control of balance often is a task per se (for example, when standing in a moving bus). Other constraints like fatigue can add to the complexity of this balance task. In the present experiment, we examined how moderate fatigue induced by fast walking on a treadmill challenged dynamic balance control. We also examined if the attentional demands for performing the balance task varied with fatigue. Subjects (n = 10) performed simultaneously a dynamic balance control task and a probe reaction time task (RT) (serving as an indicator of attentional demands) before and after three periods of moderate fatigue (fast walking on a treadmill). For the balance control task, the real-time displacement of the centre of pressure (CP) was provided on a monitor placed in front of the subject, at eye level. Subjects were asked to keep their CP within a target (moving box) moving upward and downward on the monitor. The tracking performance was measured (time spent outside the moving box) and the CP behavior analyzed (mean CP speed and mean frequency of the CP velocity). Moderate fatigue led to an immediate decrement of the performance on the balance control task; increase of the percentage of time spent outside the box and increase of the mean CP speed. Across the three fatigue periods, subjects improved their tracking performance and reduced their mean CP speed. This was achieved by increasing their frequency of actions; mean frequency of the CP velocity were higher for the fatigue periods than for the no fatigue periods. Fatigue also induced an increase in the attentional demands suggesting that more cognitive resources had to be allocated to the balance task with than without fatigue. Fatigue induced by fast walking had an initial negative impact on the control of balance. Nonetheless, subjects were able to compensate the effect of the moderate fatigue by increasing the frequency of actions. This adaptation, however, required that a greater proportion of the cognitive resources be allocated to the active control of the balance task.

Effectiveness of Neuro-Developmental Treatment (Bobath Concept) on postural control and balance in Cerebral Palsied children.

PubMed

Tekin, Fatih; Kavlak, Erdogan; Cavlak, Ugur; Altug, Filiz

2018-01-01

The aim of this study was to show the effects of an 8-week Neurodevelopmental Treatment based posture and balance training on postural control and balance in diparetic and hemiparetic Cerebral Palsied children (CPC). Fifteen CPC (aged 5-15 yrs) were recruited from Denizli Yağmur Çocukları Rehabilitation Centre. Gross Motor Function Classification System, Gross Motor Function Measure, 1-Min Walking Test, Modified Timed Up and Go Test, Paediatric Balance Scale, Functional Independence Measure for Children and Seated Postural Control Measure were used for assessment before and after treatment. An 8-week NDT based posture and balance training was applied to the CPC in one session (60-min) 2 days in a week. After the treatment program, all participants showed statistically significant improvements in terms of gross motor function (p< 0.05). They also showed statistically significant improvements about balance abilities and independence in terms of daily living activities (p< 0.05). Seated Postural Control Measure scores increased after the treatment program (p< 0.05). The results of this study indicate that an 8-week Neurodevelopmental Treatment based posture and balance training is an effective approach in order to improve functional motor level and functional independency by improving postural control and balance in diparetic and hemiparetic CPC.

Control of standing balance while using constructions stilts: comparison of expert and novice users.

PubMed

Noble, Jeremy W; Singer, Jonathan C; Prentice, Stephen D

2016-01-01

This study examined the control of standing balance while wearing construction stilts. Motion capture data were collected from nine expert stilt users and nine novices. Three standing conditions were analysed: ground, 60 cm stilts and an elevated platform. Each task was also performed with the head extended as a vestibular perturbation. Both expert and novice groups exhibited lower displacement of the whole body centre of mass and centre of pressure on construction stilts. Differences between the groups were only noted in the elevated condition with no stilts, where the expert group had lower levels of medial-lateral displacement of the centre of pressure. The postural manipulation revealed that the expert group had superior balance to the novice group. Conditions where stilts were worn showed lower levels of correspondence to the inverted pendulum model. Under normal conditions, both expert and novice groups were able to control their balance while wearing construction stilts. This work investigated the effects of experience on the control of balance while using construction stilts. Under normal conditions, expert and novice stilt users were able to control their balance while wearing construction stilts. Differences between the expert and novice users were revealed when the balance task was made more difficult, with the experts showing superior balance in these situations.

Supercritical water oxidation of products of human metabolism

NASA Technical Reports Server (NTRS)

Tester, Jefferson W.; Orge A. achelling, Richard K. ADTHOMASSON; Orge A. achelling, Richard K. ADTHOMASSON

1986-01-01

Although the efficient destruction of organic material was demonstrated in the supercritical water oxidation process, the reaction kinetics and mechanisms are unknown. The kinetics and mechanisms of carbon monoxide and ammonia oxidation in and reaction with supercritical water were studied experimentally. Experimental oxidation of urine and feces in a microprocessor controlled system was performed. A minaturized supercritical water oxidation process for space applications was design, including preliminary mass and energy balances, power, space and weight requirements.

Building Better Armies: An Insider’s Account of Liberia

DTIC Science & Technology

2013-11-01

penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. 1. REPORT DATE NOV 2013 2... inform different ideas about security may not easily translate into a coherent and actionable national se- curity strategy. The human security perspective...and relevance, and by support- 17 ing the creation of a balanced and effective security sector, informed by a clear understanding of its objec- tives

The Effect of Age on Improvements in Vestibulo-Ocular Reflexes and Balance Control after Acute Unilateral Peripheral Vestibular Loss.

PubMed

Scheltinga, Alja; Honegger, Flurin; Timmermans, Dionne P H; Allum, John H J

2016-01-01

An acute unilateral peripheral vestibular loss (aUVL) initially causes severe gaze and balance control problems. However, vestibulo-ocular reflexes (VOR) and balance control are nearly normal 3 months later as a result of peripheral recovery and/or central compensation. As pre-existing vestibular sensory loss is assumed to be greater in the healthy elderly, this study investigated whether improvements in VOR and balance function over time after aUVL are different for the elderly than for the young. Thirty aUVL patients divided into three age-groups were studied (8 age range 23-35, 10 with range 43-58, and 12 with range 60-74 years). To measure VOR function eye movements were recorded during caloric irrigation, rotating chair (ROT), and head impulse tests. Balance control during stance and gait was recorded as lower trunk angular velocity in the pitch and roll planes. Measurements were taken at deficit onset, and 3, 6, and 13 weeks later. There was one difference in VOR improvements over time between the age-groups: Low acceleration ROT responses were less at onset in the elderly group. Deficit side VOR responses and asymmetries in each group improved to within ranges of healthy controls at 13 weeks. Trunk sway of the elderly was greater for stance and gait at onset when compared to healthy age-matched controls and the young and greater than that of the young and controls during gait tasks at 13 weeks. The sway of the young was not different from controls at either time point. Balance control for the elderly improved slower than for the young. These results indicate that VOR improvement after an aUVL does not differ with age, except for low accelerations. Recovery rates are different between age-groups for balance control tests. Balance control in the elderly is more abnormal at aUVL onset for stance and gait tasks with the gait abnormalities remaining after 13 weeks. Thus, we conclude that balance control in the elderly is more affected by the UVL than for the young, and the young overcome balance deficits more rapidly. These differences with age should be taken into account when planning rehabilitation.

Variations in Urine Calcium Isotope: Composition Reflect Changes in Bone Mineral Balance in Humans

NASA Technical Reports Server (NTRS)

Skulan, Joseph; Anbar, Ariel; Bullen, Thomas; Puzas, J. Edward; Shackelford, Linda; Smith, Scott M.

2004-01-01

Changes in bone mineral balance cause rapid and systematic changes in the calcium isotope composition of human urine. Urine from subjects in a 17 week bed rest study was analyzed for calcium isotopic composition. Comparison of isotopic data with measurements of bone mineral density and metabolic markers of bone metabolism indicates the calcium isotope composition of urine reflects changes in bone mineral balance. Urine calcium isotope composition probably is affected by both bone metabolism and renal processes. Calcium isotope. analysis of urine and other tissues may provide information on bone mineral balance that is in important respects better than that available from other techniques, and illustrates the usefulness of applying geochemical techniques to biomedical problems.

Effect of progressive resistance exercise with neuromuscular joint facilitation on the dynamic balance performance of junior soccer players.

PubMed

Wang, Hongzhao; Huo, Ming; Guan, Peipei; Onoda, Ko; Chen, Di; Huang, Qiuchen; Maruyama, Hitoshi

2015-11-01

[Purpose] The aim of this study was to investigate the change in dynamic balance performance of junior soccer players after progressive resistance treatment with neuromuscular joint facilitation (NJF). [Subjects] The subjects were 14 healthy males who were divided into two groups, namely the NJF and control groups. The NJF group consisted of 8 subjects, and the control group consisted of 6 subjects. [Methods] The participants in the NJF group received NJF progressive resistance treatment. Dynamic balance performance was measured before and after 3 weeks of exercise. [Results] Significant improvement in dynamic balance performance was observed both in the NJF and control groups. In the NJF group, dynamic balance performance was significantly increased compared with that in the control group. [Conclusion] The NJF intervention shortened movement time, which implies that NJF is effective for dynamic balance performance.

Effects of a resistance training program on balance and fatigue perception in patients with Parkinson's disease: A randomized controlled trial.

PubMed

Ortiz-Rubio, Araceli; Cabrera-Martos, Irene; Torres-Sánchez, Irene; Casilda-López, Jesús; López-López, Laura; Valenza, Marie Carmen

2017-11-22

Fatigue and balance impairment leads to a loss of independence and are important to adequately manage. The objective of this study was to examine the effects of a resistance training program on dynamic balance and fatigue in patients with Parkinson's disease (PD). Randomized controlled trial. Forty-six patients with PD were randomly allocated to an intervention group receiving a 8-week resistance training program focused on lower limbs or to a control group. Balance was assessed using the Mini-BESTest and fatigue was assessed by the Piper Fatigue Scale. Patients in the intervention group improved significantly (p<0.05) on dynamic balance (reactive postural control and total values) and perceived fatigue. An 8-week resistance training program was found to be effective at improving dynamic balance and fatigue in patients with PD. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Bilateral improvements in lower extremity function after unilateral balance training in individuals with chronic ankle instability.

PubMed

Hale, Sheri A; Fergus, Andrea; Axmacher, Rachel; Kiser, Kimberly

2014-01-01

Bilateral improvements in postural control have been reported among individuals with acute lateral ankle sprains and individuals with chronic ankle instability (CAI) when only the unstable ankle is rehabilitated. We do not know if training the stable ankle will improve function on the unstable side. To explore the effects of a unilateral balance-training program on bilateral lower extremity balance and function in individuals with CAI when only the stable limb is trained. Cohort study. University clinical research laboratory. A total of 34 volunteers (8 men, 26 women; age = 24.32 ± 4.95 years, height = 167.01 ± 9.45 cm, mass = 77.54 ± 23.76 kg) with CAI were assigned to the rehabilitation (n = 17) or control (n = 17) group. Of those, 27 (13 rehabilitation group, 14 control group) completed the study. Balance training twice weekly for 4 weeks. Foot and Ankle Disability Index (FADI), FADI Sport (FADI-S), Star Excursion Balance Test, and Balance Error Scoring System. The rehabilitation and control groups differed in changes in FADI-S and Star Excursion Balance Test scores over time. Only the rehabilitation group improved in the FADI-S and in the posteromedial and anterior reaches of the Star Excursion Balance Test. Both groups demonstrated improvements in posterolateral reach; however, the rehabilitation group demonstrated greater improvement than the control group. When the groups were combined, participants reported improvements in FADI and FADI-S scores for the unstable ankle but not the stable ankle. Our data suggest training the stable ankle may result in improvements in balance and lower extremity function in the unstable ankle. This further supports the existence of a centrally mediated mechanism in the development of postural-control deficits after injury, as well as improved postural control after rehabilitation.

Characterization and Early Detection of Balance Deficits in Fragile X Premutation Carriers With and Without Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS).

PubMed

O'Keefe, Joan A; Robertson-Dick, Erin; Dunn, Emily J; Li, Yan; Deng, Youping; Fiutko, Amber N; Berry-Kravis, Elizabeth; Hall, Deborah A

2015-12-01

Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" size 55-200 CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Core motor features include cerebellar gait ataxia and kinetic tremor, resulting in progressive mobility disability. There are no published studies characterizing balance deficits in FMR1 premutation carriers with and without FXTAS using a battery of quantitative measures to test the sensory integration underlying postural control, automatic postural reflexes, and dynamic postural stability limits. Computerized dynamic posturography (CDP) and two performance-based balance measures were administered in 44 premutation carriers, 21 with FXTAS and 23 without FXTAS, and 42 healthy controls to compare balance and functional mobility between these groups. Relationships between FMR1 molecular variables, age, and sex and CDP scores were explored. FXTAS subjects demonstrated significantly lower scores on the sensory organization test (with greatest reductions in the vestibular control of balance), longer response latencies to balance perturbations, and reduced stability limits compared to controls. Premutation carriers without FXTAS also demonstrated significantly delayed response latencies and disrupted sensory weighting for balance control. Advancing age, male sex, increased CGG repeat size, and reduced X activation of the normal allele in premutation carrier women predicted balance dysfunction. These postural control deficits in carriers with and without FXTAS implicate dysfunctional cerebellar neural networks and may provide valuable outcome markers for tailored rehabilitative interventions. Our findings suggest that CDP may provide sensitive measures for early detection of postural control impairments in at-risk carriers and better characterize balance dysfunction and progression in FXTAS.

Hemocompatible control of sulfobetaine-grafted polypropylene fibrous membranes in human whole blood via plasma-induced surface zwitterionization.

PubMed

Chen, Sheng-Han; Chang, Yung; Lee, Kueir-Rarn; Wei, Ta-Chin; Higuchi, Akon; Ho, Feng-Ming; Tsou, Chia-Chun; Ho, Hsin-Tsung; Lai, Juin-Yih

2012-12-21

In this work, the hemocompatibility of zwitterionic polypropylene (PP) fibrous membranes with varying grafting coverage of poly(sulfobetaine methacrylate) (PSBMA) via plasma-induced surface polymerization was studied. Charge neutrality of PSBMA-grafted layers on PP membrane surfaces was controlled by the low-pressure and atmospheric plasma treatment in this study. The effects of grafting composition, surface hydrophilicity, and hydration capability on blood compatibility of the membranes were determined. Protein adsorption onto the different PSBMA-grafted PP membranes from human fibrinogen solutions was measured by enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies. Blood platelet adhesion and plasma clotting time measurements from a recalcified platelet-rich plasma solution were used to determine if platelet activation depends on the charge bias of the grafted PSBMA layer. The charge bias of PSBMA layer deviated from the electrical balance of positively and negatively charged moieties can be well-controlled via atmospheric plasma-induced interfacial zwitterionization and was further tested with human whole blood. The optimized PSBMA surface graft layer in overall charge neutrality has a high hydration capability and keeps its original blood-inert property of antifouling, anticoagulant, and antithrmbogenic activities when it comes into contact with human blood. This work suggests that the hemocompatible nature of grafted PSBMA polymers by controlling grafting quality via atmospheric plasma treatment gives a great potential in the surface zwitterionization of hydrophobic membranes for use in human whole blood.

Assessing Postural Control and Postural Control Strategy in Diabetes Patients Using Innovative and Wearable Technology

PubMed Central

Najafi, Bijan; Horn, Deena; Marclay, Samuel; Crews, Ryan T.; Wu, Stephanie; Wrobel, James S.

2010-01-01

Introduction Currently, diagnosis of patients with postural instability relies on a rudimentary clinical examination. This article suggests an innovative, portable, and cost-effective prototype to evaluate balance control objectively. Methods The proposed system uses low-cost, microelectromechanical sensor, body-worn sensors (BalanSens™) to measure the motion of ankle and hip joints in three dimensions. We also integrated resulting data into a two-link biomechanical model of the human body for estimating the two-dimensional sway of the center of mass (COM) in anterior–posterior (AP) and medial–lateral (ML) directions. A new reciprocal compensatory index (RCI) was defined to quantify postural compensatory strategy (PCS) performance. To validate the accuracy of our algorithms in assessing balance, we investigated the two-dimensional sway of COM and RCI in 21 healthy subjects and 17 patients with diabetic peripheral neuropathic (DPN) complications using the system just explained. Two different conditions were examined: eyes open (EO) and eyes closed (EC) for duration of at least 30 seconds. Results were compared with center of pressure sway (COP) as measured by a pressure platform (Emed-x system, Novel Inc., Germany). To further investigate the contribution of the somatosensory (SOM) feedback to balance control, healthy subjects performed EO and EC trials while standing on both a rigid and a foam surface. Results A relatively high correlation was observed between COM measured using BalanSens and COP measured using the pressure platform (r = 0.92). Results demonstrated that DPN patients exhibit significantly greater COM sway than healthy subjects for both EO and EC conditions (p < 0.005). The difference becomes highly pronounced while eyes are closed (197 ± 44 cm2 vs 68 ± 56 cm2). Furthermore, results showed that PCS assessed using RCI is significantly better in healthy subjects compared to DPN subjects for both EO and EC conditions, as well as in both ML and AP directions (p < 0.05). Alteration in SOM feedback in healthy subjects resulted in diminished RCI values that were similar to those seen in DPN subjects (p > 0.05). Discussion/Conclusion This study suggested an innovative system that enables the investigation of COM as well as postural control compensatory strategy in humans. Results suggest that neuropathy significantly impacts PCS. PMID:20663438

A theory of wheelchair wheelie performance.

PubMed

Kauzlarich, J J; Thacker, J G

1987-01-01

The results of this analytical study of wheelchair wheelie performance can be summarized into two wheelchair design equations, or rules of thumb, as developed in the paper. The equation containing the significant parameters involved in popping a wheelie for curb climbing is: fh = 0.8 mg theta c.g. [A] where fh is handrim force, m is the mass of the wheelchair + user less rear wheels, g is acceleration of gravity (9.807 m/s2), and theta c.g. is "c.g. angle," i.e., the angle between the vertical through the rear axle and a line connecting the rear axle and the system center-of-gravity. Equation [A] shows that reducing the mass and/or the c.g. angle will make it easier to pop a wheelie. The c.g. angle is reduced by moving the rear axle position forward on the wheelchair. Wheelie balance is the other aspect of performance considered; where the user balances the wheelchair on the rear wheels for going down curbs or just for fun. The ease with which a system can be controlled (balanced) is related to the static stability of the system. The static stability is defined as: omega 2 = mgl/J [B] where J is the mass moment of inertia at the center of gravity of the system about the direction perpendicular to the sideframe. For better wheelchair control during wheelchair balance the static stability should be reduced. Measurements of the value for the polar mass moment of inertia for a typical wheelchair + user of m = 90 kg was found to be J = 8.7 kg-m2. In order to decrease the value of the static stability, Equation [B], one can increase J or decrease m and/or l, where l is the distance from the rear axle to the c.g. of the system. It is also shown that balancing a rod in the palm of the hand (inverted pendulum) is a mathematical problem similar to the wheelie balance problem, and a rod of length 1.56 meters is similar to a wheelchair + user system mass of 90 kg. However, balancing a rod is done primarily by using visual perception, whereas wheelie balance involves human joint proprioceptors and visual plus vestibular (inner ear) perception. Thus, a simple test of determining the shortest length of rod one can balance in the palm of the hand (plus measuring handrim force capability and simple reaction time) may indicate if a wheelchair user will find it easy to do a wheelie balance.

Therapeutic Strategy for Targeting Aggressive Malignant Gliomas by Disrupting Their Energy Balance.

PubMed

Hegazy, Ahmed M; Yamada, Daisuke; Kobayashi, Masahiko; Kohno, Susumu; Ueno, Masaya; Ali, Mohamed A E; Ohta, Kumiko; Tadokoro, Yuko; Ino, Yasushi; Todo, Tomoki; Soga, Tomoyoshi; Takahashi, Chiaki; Hirao, Atsushi

2016-10-07

Although abnormal metabolic regulation is a critical determinant of cancer cell behavior, it is still unclear how an altered balance between ATP production and consumption contributes to malignancy. Here we show that disruption of this energy balance efficiently suppresses aggressive malignant gliomas driven by mammalian target of rapamycin complex 1 (mTORC1) hyperactivation. In a mouse glioma model, mTORC1 hyperactivation induced by conditional Tsc1 deletion increased numbers of glioma-initiating cells (GICs) in vitro and in vivo Metabolic analysis revealed that mTORC1 hyperactivation enhanced mitochondrial biogenesis, as evidenced by elevations in oxygen consumption rate and ATP production. Inhibition of mitochondrial ATP synthetase was more effective in repressing sphere formation by Tsc1-deficient glioma cells than that by Tsc1-competent glioma cells, indicating a crucial function for mitochondrial bioenergetic capacity in GIC expansion. To translate this observation into the development of novel therapeutics targeting malignant gliomas, we screened drug libraries for small molecule compounds showing greater efficacy in inhibiting the proliferation/survival of Tsc1-deficient cells compared with controls. We identified several compounds able to preferentially inhibit mitochondrial activity, dramatically reducing ATP levels and blocking glioma sphere formation. In human patient-derived glioma cells, nigericin, which reportedly suppresses cancer stem cell properties, induced AMPK phosphorylation that was associated with mTORC1 inactivation and induction of autophagy and led to a marked decrease in sphere formation with loss of GIC marker expression. Furthermore, malignant characteristics of human glioma cells were markedly suppressed by nigericin treatment in vivo Thus, targeting mTORC1-driven processes, particularly those involved in maintaining a cancer cell's energy balance, may be an effective therapeutic strategy for glioma patients. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Tilting the balance between RNA interference and replication eradicates Leishmania RNA virus 1 and mitigates the inflammatory response.

PubMed

Brettmann, Erin A; Shaik, Jahangheer S; Zangger, Haroun; Lye, Lon-Fye; Kuhlmann, F Matthew; Akopyants, Natalia S; Oschwald, Dayna M; Owens, Katherine L; Hickerson, Suzanne M; Ronet, Catherine; Fasel, Nicolas; Beverley, Stephen M

2016-10-25

Many Leishmania (Viannia) parasites harbor the double-stranded RNA virus Leishmania RNA virus 1 (LRV1), which has been associated with increased disease severity in animal models and humans and with drug treatment failures in humans. Remarkably, LRV1 survives in the presence of an active RNAi pathway, which in many organisms controls RNA viruses. We found significant levels (0.4 to 2.5%) of small RNAs derived from LRV1 in both Leishmania braziliensis and Leishmania guyanensis, mapping across both strands and with properties consistent with Dicer-mediated cleavage of the dsRNA genome. LRV1 lacks cis- or trans-acting RNAi inhibitory activities, suggesting that virus retention must be maintained by a balance between RNAi activity and LRV1 replication. To tilt this balance toward elimination, we targeted LRV1 using long-hairpin/stem-loop constructs similar to those effective against chromosomal genes. LRV1 was completely eliminated, at high efficiency, accompanied by a massive overproduction of LRV1-specific siRNAs, representing as much as 87% of the total. For both L. braziliensis and L. guyanensis, RNAi-derived LRV1-negative lines were no longer able to induce a Toll-like receptor 3-dependent hyperinflammatory cytokine response in infected macrophages. We demonstrate in vitro a role for LRV1 in virulence of L. braziliensis, the Leishmania species responsible for the vast majority of mucocutaneous leishmaniasis cases. These findings establish a targeted method for elimination of LRV1, and potentially of other Leishmania viruses, which will facilitate mechanistic dissection of the role of LRV1-mediated virulence. Moreover, our data establish a third paradigm for RNAi-viral relationships in evolution: one of balance rather than elimination.

Effects of external loads on balance control during upright stance: experimental results and model-based predictions.

PubMed

Qu, Xingda; Nussbaum, Maury A

2009-01-01

The purpose of this study was to identify the effects of external loads on balance control during upright stance, and to examine the ability of a new balance control model to predict these effects. External loads were applied to 12 young, healthy participants, and effects on balance control were characterized by center-of-pressure (COP) based measures. Several loading conditions were studied, involving combinations of load mass (10% and 20% of individual body mass) and height (at or 15% of stature above the whole-body COM). A balance control model based on an optimal control strategy was used to predict COP time series. It was assumed that a given individual would adopt the same neural optimal control mechanisms, identified in a no-load condition, under diverse external loading conditions. With the application of external loads, COP mean velocity in the anterior-posterior direction and RMS distance in the medial-lateral direction increased 8.1% and 10.4%, respectively. Predicted COP mean velocity and RMS distance in the anterior-posterior direction also increased with external loading, by 11.1% and 2.9%, respectively. Both experimental COP data and model-based predictions provided the same general conclusion, that application of larger external loads and loads more superior to the whole body center of mass lead to less effective postural control and perhaps a greater risk of loss of balance or falls. Thus, it can be concluded that the assumption about consistency in control mechanisms was partially supported, and it is the mechanical changes induced by external loads that primarily affect balance control.

40 CFR 125.58 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... this subpart. (f) Balanced indigenous population means an ecological community which: (1) Exhibits... Administrator, that the absence of a balanced indigenous population is caused solely by human perturbations...

40 CFR 125.58 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... this subpart. (f) Balanced indigenous population means an ecological community which: (1) Exhibits... Administrator, that the absence of a balanced indigenous population is caused solely by human perturbations...

40 CFR 125.58 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... this subpart. (f) Balanced indigenous population means an ecological community which: (1) Exhibits... Administrator, that the absence of a balanced indigenous population is caused solely by human perturbations...

40 CFR 125.58 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... this subpart. (f) Balanced indigenous population means an ecological community which: (1) Exhibits... Administrator, that the absence of a balanced indigenous population is caused solely by human perturbations...

40 CFR 125.58 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... this subpart. (f) Balanced indigenous population means an ecological community which: (1) Exhibits... Administrator, that the absence of a balanced indigenous population is caused solely by human perturbations...

Visuomotor control of human adaptive locomotion: understanding the anticipatory nature.

PubMed

Higuchi, Takahiro

2013-01-01

To maintain balance during locomotion, the central nervous system (CNS) accommodates changes in the constraints of spatial environment (e.g., existence of an obstacle or changes in the surface properties). Locomotion while modifying the basic movement patterns in response to such constraints is referred to as adaptive locomotion. The most powerful means of ensuring balance during adaptive locomotion is to visually perceive the environmental properties at a distance and modify the movement patterns in an anticipatory manner to avoid perturbation altogether. For this reason, visuomotor control of adaptive locomotion is characterized, at least in part, by its anticipatory nature. The purpose of the present article is to review the relevant studies which revealed the anticipatory nature of the visuomotor control of adaptive locomotion. The anticipatory locomotor adjustments for stationary and changeable environment, as well as the spatio-temporal patterns of gaze behavior to support the anticipatory locomotor adjustments are described. Such description will clearly show that anticipatory locomotor adjustments are initiated when an object of interest (e.g., a goal or obstacle) still exists in far space. This review also show that, as a prerequisite of anticipatory locomotor adjustments, environmental properties are accurately perceived from a distance in relation to individual's action capabilities.

Sensory integration balance training in patients with multiple sclerosis: A randomized, controlled trial.

PubMed

Gandolfi, Marialuisa; Munari, Daniele; Geroin, Christian; Gajofatto, Alberto; Benedetti, Maria Donata; Midiri, Alessandro; Carla, Fontana; Picelli, Alessandro; Waldner, Andreas; Smania, Nicola

2015-10-01

Impaired sensory integration contributes to balance disorders in patients with multiple sclerosis (MS). The objective of this paper is to compare the effects of sensory integration balance training against conventional rehabilitation on balance disorders, the level of balance confidence perceived, quality of life, fatigue, frequency of falls, and sensory integration processing on a large sample of patients with MS. This single-blind, randomized, controlled trial involved 80 outpatients with MS (EDSS: 1.5-6.0) and subjective symptoms of balance disorders. The experimental group (n = 39) received specific training to improve central integration of afferent sensory inputs; the control group (n = 41) received conventional rehabilitation (15 treatment sessions of 50 minutes each). Before, after treatment, and at one month post-treatment, patients were evaluated by a blinded rater using the Berg Balance Scale (BBS), Activities-specific Balance Confidence Scale (ABC), Multiple Sclerosis Quality of Life-54, Fatigue Severity Scale (FSS), number of falls and the Sensory Organization Balance Test (SOT). The experimental training program produced greater improvements than the control group training on the BBS (p < 0.001), the FSS (p < 0.002), number of falls (p = 0.002) and SOT (p < 0.05). Specific training to improve central integration of afferent sensory inputs may ameliorate balance disorders in patients with MS. Clinical Trial Registration (NCT01040117). © The Author(s), 2015.

Effect of yoga training on one leg standing and functional reach tests in obese individuals with poor postural control

PubMed Central

Jorrakate, Chaiyong; Kongsuk, Jutaluk; Pongduang, Chiraprapa; Sadsee, Boontiwa; Chanthorn, Phatchari

2015-01-01

[Purpose] The aim of the present study was to investigate the effect of yoga training on static and dynamic standing balance in obese individuals with poor standing balance. [Subjects and Methods] Sixteen obese volunteers were randomly assigned into yoga and control groups. The yoga training program was performed for 45 minutes per day, 3 times per week, for 4 weeks. Static and dynamic balance were assessed in volunteers with one leg standing and functional reach tests. Outcome measures were tested before training and after a single week of training. Two-way repeated measure analysis of variance with Tukey’s honestly significant difference post hoc statistics was used to analyze the data. [Results] Obese individuals showed significantly increased static standing balance in the yoga training group, but there was no significant improvement of static or dynamic standing balance in the control group after 4 weeks. In the yoga group, significant increases in static standing balance was found after the 2nd, 3rd, and 4th weeks. Compared with the control group, static standing balance in the yoga group was significantly different after the 2nd week, and dynamic standing balance was significantly different after the 4th week. [Conclusion] Yoga training would be beneficial for improving standing balance in obese individuals with poor standing balance. PMID:25642038

Work-Life Balance: Beyond the Rhetoric. IES Report.

ERIC Educational Resources Information Center

Kodz, J.; Harper, H.; Dench, S.

The current status of British policy and practice related to work-life balance was examined through case studies of six organizations identified as having well-developed work-life balance and flexible working practices. Interviews were conducted with human resource (HR) managers at all six organizations, and interviews and focus group discussions…

The Whole Earth Happens As You Do. The Balance of Lifekind.

ERIC Educational Resources Information Center

Archbald, David; McInnis, Noel

This booklet presents a unified perspective of natural and human systems. The problems of contemporary civilization are analyzed in terms of the interrelationships among energy, food, evolution, population, community, interactions, and balance. The authors' philosophy emphasizes that all life depends on the balance between natural systems and…

Internet-based home training is capable to improve balance in multiple sclerosis: a randomized controlled trial.

PubMed

Frevel, D; Mäurer, M

2015-02-01

Balance disorders are common in multiple sclerosis. Aim of the study is to investigate the effectiveness of an Internet-based home training program (e-Training) to improve balance in patients with multiple sclerosis. A randomized, controlled study. Academic teaching hospital in cooperation with the therapeutic riding center Gut Üttingshof, Bad Mergentheim. Eighteen multiple sclerosis patients (mean EDSS 3,5) took part in the trial. Outcome of patients using e-Training (N.=9) was compared to the outcome of patients receiving hippotherapy (N.=9), which can be considered as an advanced concept for the improvement of balance and postural control in multiple sclerosis. After simple random allocation patients received hippotherapy or Internet-based home training (balance, postural control and strength training) twice a week for 12 weeks. Assessments were done before and after the intervention and included static and dynamic balance (primary outcome). Isometric muscle strength of the knee and trunk extension/flexion (dynamometer), walking capacity, fatigue and quality of life served as secondary outcome parameters. Both intervention groups showed comparable and highly significant improvement in static and dynamic balance capacity, no difference was seen between the both intervention groups. However looking at fatigue and quality of life only the group receiving hippotherapy improved significantly. Since e-Training shows even comparable effects to hippotherapy to improve balance, we believe that the established Internet-based home training program, specialized on balance and postural control training, is feasible for a balance and strength training in persons with multiple sclerosis. We demonstrated that Internet-based home training is possible in patients with multiple sclerosis.

The energy cost for balance control during upright standing.

PubMed

Houdijk, Han; Fickert, Richard; van Velzen, Judith; van Bennekom, Coen

2009-08-01

The aim of this study was to investigate whether balance control during a static upright standing task with and without balance perturbations elicits a significant and meaningful metabolic energy demand and to test whether this energy demand correlates with conventional posturography measures for balance control. Ten healthy subjects were assessed in four 4-min upright standing conditions on a force platform while energy consumption was measured using open circuit respirometry. In the reference condition subjects stood upright in parallel stance without balance perturbation (PS). In the other conditions balance was perturbed by placing the subjects in tandem stance (TS), in tandem stance blind folded (TSBF) and in tandem stance on a balance board (TSBB). Gross and net energy consumption was assessed and various conventional posturography measures were derived from the excursion of the center of pressure (CoP) of the ground reaction force. Energy consumption was substantially affected by all balance perturbations, compared to the reference condition. The highest increase in energy consumption was found for the TSBF condition (increase of 0.86 J kg(-1)s(-1) or 60% of PS). Significant correlations were found between energy consumption and posturography measures. The strongest correlation was found between gross energy consumption and the CoP path and normalized CoP path along the anterior-posterior axis (resp. r=0.57 and r=0.66, p<0.001). It was concluded that the effort for balance control can elicit a meaningful metabolic energy demand. Conventional posturography provided significant, though moderate, predictors of this metabolic effort for balance control.

Effects of balance Vestibular Rehabilitation Therapy in elderly with Benign Paroxysmal Positional Vertigo: a randomized controlled trial.

PubMed

Ribeiro, Karyna Myrelly Oliveira Bezerra de Figueiredo; Freitas, Raysa Vanessa de Medeiros; Ferreira, Lidiane Maria de Brito Macedo; Deshpande, Nandini; Guerra, Ricardo Oliveira

2017-06-01

To evaluate short-term effects of balance Vestibular Rehabilitation Therapy (VRT) on balance, dizziness symptoms and quality of life of the elderly with chronic Benign Paroxysmal Positional Vertigo (BPPV). In this randomized, single-blind and controlled trial, older adults with chronic BPPV were randomized into two groups, the experimental group (n = 7, age: 69 (65-78) years) and the control group (n = 7, age: 73 (65-76) years). Patients in the experimental group underwent balance VRT (50 min per session, two times a week) and Canalith Repositioning Maneuver (CRM) as required, for 13 weeks. The control group was treated using only CRM as required. Standing and dynamic balance, dizziness symptoms and quality of life were measured at the baseline, and at one, five, nine and thirteen weeks. There were no between-group differences in dizziness, quality of life and standing balance over the 13 weeks. Significant differences were observed in dynamic balance measures between groups (p <  0.05 for most tests) through assessments. In intragroup analysis, both groups showed improvements in all measurements except no improvement was found in majority of the dynamic balance tests in the control group. The patients who received additional balance VRT demonstrated better results in dynamic balance than those who received only CRM. Implications for Rehabilitation The findings that balance VRT in addition to CRM improves dynamic balance in elderly people with BPPV should be useful in guiding rehabilitation professionals' clinical decision making to design interventions for seniors suffering from BPPV; Improvements in tests of dynamic balance suggest that the risk of adverse consequences of BPPV in the elderly such as falls and fractures can be potentially reduced through implementation of CRM in conjunction with balance VRT; Lack of additional improvement in Visual Analogue Scale of dizziness and Dizziness Handicap Index suggests that addition of balance VRT does not influence dizziness symptomatology, per se, and CRM alone is effective to ameliorate vertiginous symptoms and potentially improve quality of life.

BMP signaling inhibits intestinal stem cell self-renewal through suppression of Wnt-beta-catenin signaling.

PubMed

He, Xi C; Zhang, Jiwang; Tong, Wei-Gang; Tawfik, Ossama; Ross, Jason; Scoville, David H; Tian, Qiang; Zeng, Xin; He, Xi; Wiedemann, Leanne M; Mishina, Yuji; Li, Linheng

2004-10-01

In humans, mutations in BMPR1A, SMAD4 and PTEN are responsible for juvenile polyposis syndrome, juvenile intestinal polyposis and Cowden disease, respectively. The development of polyposis is a common feature of these diseases, suggesting that there is an association between BMP and PTEN pathways. The mechanistic link between BMP and PTEN pathways and the related etiology of juvenile polyposis is unresolved. Here we show that conditional inactivation of Bmpr1a in mice disturbs homeostasis of intestinal epithelial regeneration with an expansion of the stem and progenitor cell populations, eventually leading to intestinal polyposis resembling human juvenile polyposis syndrome. We show that BMP signaling suppresses Wnt signaling to ensure a balanced control of stem cell self-renewal. Mechanistically, PTEN, through phosphatidylinosital-3 kinase-Akt, mediates the convergence of the BMP and Wnt pathways on control of beta-catenin. Thus, BMP signaling may control the duplication of intestinal stem cells, thereby preventing crypt fission and the subsequent increase in crypt number.

Relationship between asymmetry of quiet standing balance control and walking post-stroke.

PubMed

Hendrickson, Janna; Patterson, Kara K; Inness, Elizabeth L; McIlroy, William E; Mansfield, Avril

2014-01-01

Spatial and temporal gait asymmetry is common after stroke. Such asymmetric gait is inefficient, can contribute to instability and may lead to musculoskeletal injury. However, understanding of the determinants of such gait asymmetry remains incomplete. The current study is focused on revealing if there is a link between asymmetry during the control of standing balance and asymmetry during walking. This study involved review of data from 94 individuals with stroke referred to a gait and balance clinic. Participants completed three tests: (1) walking at their usual pace; (2) quiet standing; and (3) standing with maximal loading of the paretic side. A pressure sensitive mat recorded placement and timing of each footfall during walking. Standing tests were completed on two force plates to evaluate symmetry of weight bearing and contribution of each limb to balance control. Multiple regression was conducted to determine the relationships between symmetry during standing and swing time, stance time, and step length symmetry during walking. Symmetry of antero-posterior balance control and weight bearing were related to swing time and step length symmetry during walking. Weight-bearing symmetry, weight-bearing capacity, and symmetry of antero-posterior balance control were related to stance time symmetry. These associations were independent of underlying lower limb impairment. The results support the hypothesis that impaired ability of the paretic limb to control balance may contribute to gait asymmetry post-stroke. Such work suggests that rehabilitation strategies that increase the contribution of the paretic limb to standing balance control may increase symmetry of walking post-stroke. Copyright © 2013 Elsevier B.V. All rights reserved.

Climate Change Predominantly Caused U.S. Soil Water Storage Decline from 2003 to 2014

NASA Astrophysics Data System (ADS)

Zhang, X.; Ma, C.; Song, X.; Gao, L.; Liu, M.; Xu, X.

2016-12-01

The water storage in soils is a fundamental resource for natural ecosystems and human society, while it is highly variable due to its complicated controlling factors in a changing climate; therefore, understanding water storage variation and its controlling factors is essential for sustaining human society, which relies on water resources. Although we are confident for water availability at global scale, the regional-scale water storage and its controlling factors are not fully understood. A number of researchers have reported that water resources are expected to diminish as climate continues warming in the 21stcentury, which will further influence human and ecological systems. However, few studies to date have fully quantitatively examined the water balances and its individual controlling mechanisms in the conterminous US. In this study, we integrated the time-series data of water storage and evapotranspiration derived from satellite imageries, regional meteorological data, and social-economic water consumption, to quantify water storage dynamics and its controlling factors across the conterminous US from 2003 to 2014. The water storage decline was found in majority of conterminous US, with the largest decline in southwestern US. Net atmospheric water input, which is difference between precipitation and evapotranspiration, could explain more than 50% of the inter-annual variation of water storage variation in majority of US with minor contributions from human water consumption. Climate change, expressed as precipitation decreases and warming, made dominant contribution to the water storage decline in the conterminous U.S. from 2003 to 2014.

[Brief disserting on the balance of internal environment in burn disease].

PubMed

Han, C M; Wang, X G

2017-08-20

The essential internal environment in human being involves water, electrolyte, and acid-base balance, which is the basis of balance and stability of internal environment in other systems. For burn patients, the balance of internal environment, referring to metabolism, nutrition, inflammatory response, and immunoreaction, is one of the most important aspects in burn disease. This paper aims to briefly elaborate the balance of internal environment after burn, with the purpose to promote the basic and clinical research in this field.

Creative Dance Practice Improves Postural Control in a Child With Cerebral Palsy.

PubMed

Stribling, Kate; Christy, Jennifer

2017-10-01

To investigate the effect of creative dance instruction on postural control and balance in an 11-year-old with spastic triplegic cerebral palsy, Gross Motor Function Classification Scale level II. We conducted 1-hour dance interventions twice weekly for 8 weeks, with a focus on somatosensory awareness and movement in all planes of motion. Computerized dynamic posturography using the SMART Balance Master/EquiTest (NeuroCom) was used to assess postural control and balance reactions before the first class and following the final class. Gains in standing stability, balance recovery, directional control, and endpoint excursion of movement were found. Participation in creative dance lessons appears to improve somatosensory effectiveness and postural control in a child with cerebral palsy. Dance is a fun way to improve balance and coordination. These interventions could be easily implemented into programs for children with cerebral palsy.

Human genome and open source: balancing ethics and business.

PubMed

Marturano, Antonio

2011-01-01

The Human Genome Project has been completed thanks to a massive use of computer techniques, as well as the adoption of the open-source business and research model by the scientists involved. This model won over the proprietary model and allowed a quick propagation and feedback of research results among peers. In this paper, the author will analyse some ethical and legal issues emerging by the use of such computer model in the Human Genome property rights. The author will argue that the Open Source is the best business model, as it is able to balance business and human rights perspectives.

The prevention of TNF-α/IFN-γ mixture-induced inflammation in human keratinocyte and atopic dermatitis-like skin lesions in Nc/Nga mice by mineral-balanced deep sea water.

PubMed

Lee, Kyu-Shik; Chun, So-Young; Lee, Min-Gu; Kim, Soyoung; Jang, Tae-Jung; Nam, Kyung-Soo

2018-01-01

Atopic dermatitis (AD) is a chronic inflammatory skin disease caused by environmental and chemical allergens. Despite the complexity of its pathogenesis, many investigations have shown that substances having anti-inflammatory activities alleviated the pathology of AD. Here, we evaluated the effects of mineral-balanced deep sea water (DSW) on AD-like skin damage in both in vitro and in vivo. The results showed that mineral-balanced DSW regressed inflammatory chemokines, such as macrophage-derived chemokine (MDC), thymus- and activation-regulated chemokine (TARC) and regulated on activation, normal T-cell expressed and secreted (RANTES), and cytokines, interleukin (IL)-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA expression in HaCaT immortal human keratinocyte treated with tumor necrosis factor (TNF)-α/ interferon (IFN)-γ mixture. Furthermore, increased cyclooxygenase (COX)-2 protein expressions were also reversed, filaggrin gene expression was enhanced and decreased involucrin transcriptions was recovered by mineral-balanced DSW in TNF-α/IFN-γ mixture-treated HaCaT human keratinocyte. Moreover, we revealed that the inhibitory effects of mineral-balanced DSW were mediated with the suppression of signal transducer and activator of transcription (STAT) 1 phosphorylation. In animal experiments, we showed that hardness 2000 of mineral-balanced DSW decreased the serum levels of IgE, IL-4, and histamine, and alleviated the severity score and numbers of scratching in dinitrochlorobezene (DNCB)-treated Nc/Nga mice. Furthermore, increased epidermal thickness and mast cell infiltration by DNCB treatment were reversed by the application of hardness 2000 mineral-balanced DSW. Taken together, the present investigation indicates that mineral-balanced DSW is a potent substance with anti-atopic dermatitis activity. Copyright © 2017. Published by Elsevier Masson SAS.

Modeling large-scale human alteration of land surface hydrology and climate

NASA Astrophysics Data System (ADS)

Pokhrel, Yadu N.; Felfelani, Farshid; Shin, Sanghoon; Yamada, Tomohito J.; Satoh, Yusuke

2017-12-01

Rapidly expanding human activities have profoundly affected various biophysical and biogeochemical processes of the Earth system over a broad range of scales, and freshwater systems are now amongst the most extensively altered ecosystems. In this study, we examine the human-induced changes in land surface water and energy balances and the associated climate impacts using a coupled hydrological-climate model framework which also simulates the impacts of human activities on the water cycle. We present three sets of analyses using the results from two model versions—one with and the other without considering human activities; both versions are run in offline and coupled mode resulting in a series of four experiments in total. First, we examine climate and human-induced changes in regional water balance focusing on the widely debated issue of the desiccation of the Aral Sea in central Asia. Then, we discuss the changes in surface temperature as a result of changes in land surface energy balance due to irrigation over global and regional scales. Finally, we examine the global and regional climate impacts of increased atmospheric water vapor content due to irrigation. Results indicate that the direct anthropogenic alteration of river flow in the Aral Sea basin resulted in the loss of 510 km3 of water during the latter half of the twentieth century which explains about half of the total loss of water from the sea. Results of irrigation-induced changes in surface energy balance suggest a significant surface cooling of up to 3.3 K over 1° grids in highly irrigated areas but a negligible change in land surface temperature when averaged over sufficiently large global regions. Results from the coupled model indicate a substantial change in 2 m air temperature and outgoing longwave radiation due to irrigation, highlighting the non-local (regional and global) implications of irrigation. These results provide important insights on the direct human alteration of land surface water and energy balances, highlighting the need to incorporate human activities such as irrigation into the framework of global climate models and Earth system models for better prediction of future changes under increasing human influence and continuing global climate change.

The effect of therapeutic horseback riding on balance in community-dwelling older adults: a pilot study.

PubMed

Homnick, Tamara D; Henning, Kim M; Swain, Charlene V; Homnick, Douglas N

2015-02-01

Equine assisted activities (hippotherapy and therapeutic riding) improve balance in patients with disabilities such as cerebral palsy, but have not been systematically studied in older adults, at risk of falls due to balance deficits. We conducted a 10-week, single blind, controlled trial of the effect of a therapeutic horseback riding course on measures of balance in community-dwelling adults 65 years and older. Nine riders and six controls completed the trial. Controls were age matched to riders and all participants were recruited from the local community. Both groups showed improvements in balance during the trial, but did not reach statistical significance. Sample size was small, participants had relatively high initial balance scores, and controls tended to increase their physical activities, likely influencing outcomes. No adverse events occurred and the supervised therapeutic riding program appeared to be a safe and effective form of exercise to improve balance in older adults. A power analysis was performed to estimate numbers of participants needed for a larger study. © The Author(s) 2012.

Biology and pathological implications of brown adipose tissue: promises and caveats for the control of obesity and its associated complications.

PubMed

Tapia, Pablo; Fernández-Galilea, Marta; Robledo, Fermín; Mardones, Pablo; Galgani, José E; Cortés, Víctor A

2018-05-01

The discovery of metabolically active brown adipose tissue (BAT) in adult humans has fuelled the research of diverse aspects of this previously neglected tissue. BAT is solely present in mammals and its clearest physiological role is non-shivering thermogenesis, owing to the capacity of brown adipocytes to dissipate metabolic energy as heat. Recently, a number of other possible functions have been proposed, including direct regulation of glucose and lipid homeostasis and the secretion of a number of factors with diverse regulatory actions. Herein, we review recent advances in general biological knowledge of BAT and discuss the possible implications of this tissue in human metabolic health. In particular, we confront the claimed thermogenic potential of BAT for human energy balance and body mass regulation, mostly based on animal studies, with the most recent quantifications of human BAT. © 2017 Cambridge Philosophical Society.

Systematic Review of Postural Control and Lateral Ankle Instability, Part II: Is Balance Training Clinically Effective

PubMed Central

McKeon, Patrick O; Hertel, Jay

2008-01-01

Objective: To answer the following clinical questions: (1) Can prophylactic balance and coordination training reduce the risk of sustaining a lateral ankle sprain? (2) Can balance and coordination training improve treatment outcomes associated with acute ankle sprains? (3) Can balance and coordination training improve treatment outcomes in patients with chronic ankle instability? Data Sources: PubMed and CINAHL entries from 1966 through October 2006 were searched using the terms ankle sprain, ankle instability, balance, chronic ankle instability, functional ankle instability, postural control, and postural sway. Study Selection: Only studies assessing the influence of balance training on the primary outcomes of risk of ankle sprain or instrumented postural control measures derived from testing on a stable force plate using the modified Romberg test were included. Studies had to provide results for calculation of relative risk reduction and numbers needed to treat for the injury prevention outcomes or effect sizes for the postural control measures. Data Extraction: We calculated the relative risk reduction and numbers needed to treat to assess the effect of balance training on the risk of incurring an ankle sprain. Effect sizes were estimated with the Cohen d for comparisons of postural control performance between trained and untrained groups. Data Synthesis: Prophylactic balance training substantially reduced the risk of sustaining ankle sprains, with a greater effect seen in those with a history of a previous sprain. Completing at least 6 weeks of balance training after an acute ankle sprain substantially reduced the risk of recurrent ankle sprains; however, consistent improvements in instrumented measures of postural control were not associated with training. Evidence is lacking to assess the reduction in the risk of recurrent sprains and inconclusive to demonstrate improved instrumented postural control measures in those with chronic ankle instability who complete balance training. Conclusions: Balance training can be used prophylactically or after an acute ankle sprain in an effort to reduce future ankle sprains, but current evidence is insufficient to assess this effect in patients with chronic ankle instability. PMID:18523567

The Relationship of Value Orientations, Self-Control, Frequency of School-Leisure Conflicts, and Life-Balance in Adolescence

ERIC Educational Resources Information Center

Kuhnle, Claudia; Hofer, Manfred; Kilian, Britta

2010-01-01

The aim of this self-report study is to analyze proposed interrelations between value orientations, self-control, frequency of school-leisure conflicts, and life-balance in adolescence. Life-balance is defined as satisfying time investment in different life areas. The tested model posits that self-control is negatively related to conflict…

Effect of lung resection on pleuro-pulmonary mechanics and fluid balance.

PubMed

Salito, C; Bovio, D; Orsetti, G; Salati, M; Brunelli, A; Aliverti, A; Miserocchi, G

2016-01-15

The aim of the study was to determine in human patients the effect of lung resection on lung compliance and on pleuro-pulmonary fluid balance. Pre and post-operative values of compliance were measured in anesthetized patients undergoing resection for lung cancer (N=11) through double-lumen bronchial intubation. Lung compliance was measured for 10-12 cm H2O increase in alveolar pressure from 5 cm H2O PEEP in control and repeated after resection. No air leak was assessed and pleural fluid was collected during hospital stay. A significant negative correlation (r(2)=0.68) was found between compliance at 10 min and resected mass. Based on the pre-operative estimated lung weight, the decrease in compliance following lung resection exceeded by 10-15% that expected from resected mass. Significant negative relationships were found by relating pleural fluid drainage flow to the remaining lung mass and to post-operative lung compliance. Following lung re-expansion, data suggest a causative relationship between the decrease in compliance and the perturbation in pleuro-pulmonary fluid balance. Copyright © 2015 Elsevier B.V. All rights reserved.

Traditional Chinese Medicine, Food Therapy, and Hypertension Control: A Narrative Review of Chinese Literature.

PubMed

Zou, Ping

2016-01-01

Despite the lack of English literature about Traditional Chinese Medicine (TCM) food therapy, there is abundant Chinese literature about the application of food therapy for hypertension control. This paper summarizes basic concepts of TCM, the principles of food therapy and its application for hypertension control according to Chinese literature. In TCM, food is conceptualized according to both nutritional and functional aspects, and can be used to treat illnesses. Four principles of TCM food therapy including light eating, balancing the "hot" and "cold" nature of food, the harmony of the five flavors of food, and consistency between dietary intake and different health conditions, can be used to facilitate hypertension control. Based on a statistical analysis of antihypertensive foods recommended in 20 books on the application of food therapy for hypertension control, the 38 most frequently recommended are celery, tomato, banana, hawthorn, garlic, onion, seaweed, apple, corn, green beans, persimmon, laver, kiwi, watermelon, eggplant, carrots, mushroom, peanut, soy products, sea cucumber, buckwheat, garland chrysanthemum, spinach, honey, dairy products, vinegar, black fungus, jellyfish, green onion, shepherd's purse, soybean, potato, pear, winter melon, bitter melon, oat, pea, and tea. Food therapy emphasizes the therapeutic effects of food, considering its nature, taste, and function on human balanced health, which leads to optimal blood pressure control. Current literature suggests that food therapy is effective in blood pressure control and can be incorporated into blood pressure self-management in the Chinese population.

Population and prehistory II: Space-limited human populations in constant environments

PubMed Central

Puleston, Cedric O.; Tuljapurkar, Shripad

2010-01-01

We present a population model to examine the forces that determined the quality and quantity of human life in early agricultural societies where cultivable area is limited. The model is driven by the non-linear and interdependent relationships between the age distribution of a population, its behavior and technology, and the nature of its environment. The common currency in the model is the production of food, on which age-specific rates of birth and death depend. There is a single nontrivial equilibrium population at which productivity balances caloric needs. One of the most powerful controls on equilibrium hunger level is fertility control. Gains against hunger are accompanied by decreases in population size. Increasing worker productivity does increase equilibrium population size but does not improve welfare at equilibrium. As a case study we apply the model to the population of a Polynesian valley before European contact. PMID:18598711

Host control of human papillomavirus infection and disease.

PubMed

Doorbar, John

2018-02-01

Most human papillomaviruses cause inapparent infections, subtly affecting epithelial homeostasis, to ensure genome persistence in the epithelial basal layer. As with conspicuous papillomas, these self-limiting lesions shed viral particles to ensure population level maintenance and depend on a balance between viral gene expression, immune cell stimulation and immune surveillance for persistence. The complex immune evasion strategies, characteristic of high-risk HPV types, also allow the deregulated viral gene expression that underlies neoplasia. Neoplasia occurs at particular epithelial sites where vulnerable cells such as the reserve or cuboidal cells of the cervical transformation zone are found. Beta papillomavirus infection can also predispose an individual with immune deficiencies to the development of cancers. The host control of HPV infections thus involves local interactions between keratinocytes and the adaptive immune response. Effective immune detection and surveillance limits overt disease, leading to HPV persistence as productive microlesions or in a true latent state. Copyright © 2017. Published by Elsevier Ltd.

Some of Indonesian Cyber Law Problems

NASA Astrophysics Data System (ADS)

Machmuddin, D. D.; Pratama, B.

2017-01-01

Cyber regulation is very important to control human interaction within the Internet network in cyber space. On the surface, innovation development in science and technology facilitates human activity. But on the inside, innovation was controlled by new business model. In cyber business activities mingle with individual protection. By this condition, the law should keep the balance of the activities. Cyber law problems, were not particular country concern, but its global concern. This is a good opportunity for developing country to catch up with developed country. Beside this opportunity for talented people in law and technology is become necessity. This paper tries to describe cyber law in Indonesia. As a product of a developing country there are some of weakness that can be explained. Terminology and territory of cyber space is become interesting to discuss, because this two problems can give a broad view on cyber law in Indonesia.

Nitric oxide synthesis in patients with advanced HIV infection.

PubMed Central

Evans, T G; Rasmussen, K; Wiebke, G; Hibbs, J B

1994-01-01

The discovery that humans produce nitric oxide and that this molecule plays an important role in cell communication, host resistance to infection, and perhaps in host defence to neoplastic disease, has created much interest in further research on its function in the body. A cytokine-inducible high output L-arginine/nitric oxide pathway was recently detected in patients with advanced malignancy treated with IL-2. The production of nitric oxide was thus examined in patients with advanced HIV infection and in intensive care unit control patients. Extrinsic nitrate and nitrite consumption were carefully controlled in the diet or through the use of total parenteral nutrition. Seven of eight HIV+ patients were placed into positive nitrogen balance. Nitric oxide synthesis was found to be within the normal human range. In contrast, nitric oxide synthesis in extremely ill intensive care unit patients was low normal to depressed. PMID:8033424

Physiological principles of vestibular function on earth and in space

NASA Technical Reports Server (NTRS)

Minor, L. B.

1998-01-01

Physiological mechanisms underlying vestibular function have important implications for our ability to understand, predict, and modify balance processes during and after spaceflight. The microgravity environment of space provides many unique opportunities for studying the effects of changes in gravitoinertial force on structure and function of the vestibular system. Investigations of basic vestibular physiology and of changes in reflexes occurring as a consequence of exposure to microgravity have important implications for diagnosis and treatment of vestibular disorders in human beings. This report reviews physiological principles underlying control of vestibular processes on earth and in space. Information is presented from a functional perspective with emphasis on signals arising from labyrinthine receptors. Changes induced by microgravity in linear acceleration detected by the vestibulo-ocular reflexes. Alterations of the functional requirements for postural control in space are described. Areas of direct correlation between studies of vestibular reflexes in microgravity and vestibular disorders in human beings are discussed.

Population and prehistory II: space-limited human populations in constant environments.

PubMed

Puleston, Cedric O; Tuljapurkar, Shripad

2008-09-01

We present a population model to examine the forces that determined the quality and quantity of human life in early agricultural societies where cultivable area is limited. The model is driven by the non-linear and interdependent relationships between the age distribution of a population, its behavior and technology, and the nature of its environment. The common currency in the model is the production of food, on which age-specific rates of birth and death depend. There is a single non-trivial equilibrium population at which productivity balances caloric needs. One of the most powerful controls on equilibrium hunger level is fertility control. Gains against hunger are accompanied by decreases in population size. Increasing worker productivity does increase equilibrium population size but does not improve welfare at equilibrium. As a case study we apply the model to the population of a Polynesian valley before European contact.

The "balance of nature"-evolution of a Panchreston.

PubMed

Simberloff, Daniel

2014-10-01

The earliest concept of a balance of nature in Western thought saw it as being provided by gods but requiring human aid or encouragement for its maintenance. With the rise of Greek natural philosophy, emphasis shifted to traits gods endowed species with at the outset, rather than human actions, as key to maintaining the balance. The dominance of a constantly intervening God in the Middle Ages lessened interest in the inherent features of nature that would contribute to balance, but the Reformation led to renewed focus on such features, particularly traits of species that would maintain all of them but permit none to dominate nature. Darwin conceived of nature in balance, and his emphasis on competition and frequent tales of felicitous species interactions supported the idea of a balance of nature. But Darwin radically changed its underlying basis, from God to natural selection. Wallace was perhaps the first to challenge the very notion of a balance of nature as an undefined entity whose accuracy could not be tested. His skepticism was taken up again in the 20th century, culminating in a widespread rejection of the idea of a balance of nature by academic ecologists, who focus rather on a dynamic, often chaotic nature buffeted by constant disturbances. The balance-of-nature metaphor, however, lives on in large segments of the public, representing a fragile aspect of nature and biodiversity that it is our duty to protect.

Identification of Balance Deficits in People with Parkinson Disease; is the Sensory Organization Test Enough?

PubMed

Gera, G; Freeman, D L; Blackinton, M T; Horak, F B; King, L

2016-02-01

Balance deficits in people with Parkinson's disease can affect any of the multiple systems encompassing balance control. Thus, identification of the specific deficit is crucial in customizing balance rehabilitation. The sensory organization test, a test of sensory integration for balance control, is sometimes used in isolation to identify balance deficits in people with Parkinson's disease. More recently, the Mini-Balance Evaluations Systems Test, a clinical scale that tests multiple domains of balance control, has begun to be used to assess balance in patients with Parkinson's disease. The purpose of our study was to compare the use of Sensory Organization Test and Mini-Balance Evaluations Systems Test in identifying balance deficits in people with Parkinson's disease. 45 participants (27M, 18F; 65.2 ± 8.2 years) with idiopathic Parkinson's disease participated in the cross-sectional study. Balance assessment was performed using the Sensory Organization Test and the Mini-Balance Evaluations Systems Test. People were classified into normal and abnormal balance based on the established cutoff scores (normal balance: Sensory Organization Test >69; Mini-Balance Evaluations Systems Test >73). More subjects were classified as having abnormal balance with the Mini-Balance Evaluations Systems Test (71% abnormal) than with the Sensory Organization Test (24% abnormal) in our cohort of people with Parkinson's disease. There were no subjects with a normal Mini-Balance Evaluations Systems Test score but abnormal Sensory Organization Test score. In contrast, there were 21 subjects who had an abnormal Mini-Balance Evaluations Systems Test score but normal Sensory Organization Test scores. Findings from this study suggest that investigation of sensory integration deficits, alone, may not be able to identify all types of balance deficits found in patients with Parkinson's disease. Thus, a comprehensive approach should be used to test of multiple balance systems to provide customized rehabilitation.

Understanding balance differences in individuals with multiple sclerosis with mild disability: An investigation of differences in sensory feedback on postural and dynamic balance control

NASA Astrophysics Data System (ADS)

Denomme, Luke T.

Multiple sclerosis (MS) is an autoimmune disease that affects the central nervous system (CNS) and causes a broad range of neurological symptoms. One of the most common symptoms experienced by individuals with MS is poor balance control during standing and walking. The main mechanism underlying impaired balance control in MS appears to result from slowed somatosensory conduction and impaired central integration. The current thesis assessed postural and dynamic control of balance of 'individuals with MS with mild disability' (IwMS). IwMS were compared to 'healthy age-matched individuals' (HAMI) and community-dwelling 'older adults' (OA). The purpose of this thesis was to quantify differences in postural and dynamic control of balance in IwMS to the two populations who display balance control differences across the lifespan and represent two extreme ends of the balance control continuum due to natural aging. IwMS (n = 12, x¯age: 44 +/- 9.4 years), HAMI (n = 12, x¯age: 45 +/- 9.9 years) and community-dwelling OA (n = 12, x¯ age: 68.1 +/- 4.5 years) postural and dynamic balance control were evaluated during a Romberg task as well as a dynamic steering task. The Romberg task required participants to stand with their feet together and hands by their sides for 45 seconds with either their eyes open or closed. The dynamic steering task required participants to walk and change direction along the M-L plane towards a visual goal. Results from these two tasks reveal that IwMS display differences in postural control when compared to HAMI when vision was removed as well as differences in dynamic stability margin during steering situations. During the postural control task IwMS displayed faster A-P and M-L COP velocities when vision was removed and their COP position was closer to their self-selected maximum stability limits compared to HAMI. Assessment of dynamic stability during the steering task revealed that IwMS displayed reduced walking speed and cadence during the straight walking portion of the task in addition to a smaller DSM range (i.e., COM remained close to lateral BOS) during the entire steering task. These results suggest that IwMS adopt postural and dynamic control strategies (i.e., increased COP velocity, smaller self-selected maximal sway comfort zones and reduced walking speed) in order to maintain stability and complete the tasks. Results further revealed that IwMS display similar levels of postural and dynamic stability to OA despite differences in the type of sensory impairment possessed by each group. The findings also provide insights into the comparison of IwMS to two populations who represent the two extreme ends of the balance control continuum: HAMI and OA. Our data indicates that the level of postural and dynamic balance control in IwMS appears to express similar characteristics and may be located closer to the OA population on this continuum. Future research should evaluate the level of somatosensory impairment (i.e., monofilament testing and tuning fork tendon tap testing) between IwMS and OA in order to better differentiate levels of postural and dynamic balance control between groups and to gain a better understanding of where each group may be specifically located on the age-related balance control continuum.

Regulation of lipid deposition in farm animals: Parallels between agriculture and human physiology.

PubMed

Bergen, Werner G; Brandebourg, Terry D

2016-06-01

For many years, clinically oriented scientists and animal scientists have focused on lipid metabolism and fat deposition in various fat depots. While dealing with a common biology across species, the goals of biomedical and food animals lipid metabolism research differ in emphasis. In humans, mechanisms and regulation of fat synthesis, accumulation of fat in regional fat depots, lipid metabolism and dysmetabolism in adipose, liver and cardiac tissues have been investigated. Further, energy balance and weight control have also been extensively explored in humans. Finally, obesity and associated maladies including high cholesterol and atherosclerosis, cardiovascular disease, insulin resistance, hypertension, metabolic syndrome and health outcomes have been widely studied. In food animals, the emphasis has been on regulation of fatty acid synthesis and lipid deposition in fat depots and deposition of intramuscular fat. For humans, understanding the regulation of energy balance and body weight and of prevention or treatment of obesity and associated maladies have been important clinical outcomes. In production of food animals lowering fat content in muscle foods while enhancing intramuscular fat (marbling) have been major targets. In this review, we summarize how our laboratories have addressed the goal of providing lean but yet tasty and juicy muscle food products to consumers. In addition, we here describe efforts in the development of a new porcine model to study regulation of fat metabolism and obesity. Commonalities and differences in regulation of lipid metabolism between humans, rodents and food animals are emphasized throughout this review. © 2016 by the Society for Experimental Biology and Medicine.

Virtual Balancing for Studying and Training Postural Control.

PubMed

Buettner, Daniela; Dalin, Daniela; Wiesmeier, Isabella K; Maurer, Christoph

2017-01-01

Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We conclude that virtual balancing may be well suited to simulate conditions which could otherwise only be realized in space experiments or during parabolic flights. Further studies are needed to examine patients' potential benefit of virtual balance training.

Virtual Balancing for Studying and Training Postural Control

PubMed Central

Buettner, Daniela; Dalin, Daniela; Wiesmeier, Isabella K.; Maurer, Christoph

2017-01-01

Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We conclude that virtual balancing may be well suited to simulate conditions which could otherwise only be realized in space experiments or during parabolic flights. Further studies are needed to examine patients' potential benefit of virtual balance training. PMID:29018320

The gait and balance of patients with diabetes can be improved: a randomised controlled trial.

PubMed

Allet, L; Armand, S; de Bie, R A; Golay, A; Monnin, D; Aminian, K; Staal, J B; de Bruin, E D

2010-03-01

Gait characteristics and balance are altered in diabetic patients. Little is known about possible treatment strategies. This study evaluates the effect of a specific training programme on gait and balance of diabetic patients. This was a randomised controlled trial (n=71) with an intervention (n=35) and control group (n=36). The intervention consisted of physiotherapeutic group training including gait and balance exercises with function-orientated strengthening (twice weekly over 12 weeks). Controls received no treatment. Individuals were allocated to the groups in a central office. Gait, balance, fear of falls, muscle strength and joint mobility were measured at baseline, after intervention and at 6-month follow-up. The trial is closed to recruitment and follow-up. After training, the intervention group increased habitual walking speed by 0.149 m/s (p<0.001) compared with the control group. Patients in the intervention group also significantly improved their balance (time to walk over a beam, balance index recorded on Biodex balance system), their performance-oriented mobility, their degree of concern about falling, their hip and ankle plantar flexor strength, and their hip flexion mobility compared with the control group. After 6 months, all these variables remained significant except for the Biodex sway index and ankle plantar flexor strength. Two patients developed pain in their Achilles tendon: the progression for two related exercises was slowed down. Specific training can improve gait speed, balance, muscle strength and joint mobility in diabetic patients. Further studies are needed to explore the influence of these improvements on the number of reported falls, patients' physical activity levels and quality of life. ClinicalTrials.gov NCT00637546 This work was supported by the Swiss National Foundation (SNF): PBSKP-123446/1/

Microchip dual-frequency laser with well-balanced intensity utilizing temperature control.

PubMed

Hu, Miao; Zhang, Yu; Wei, Mian; Zeng, Ran; Li, Qiliang; Lu, Yang; Wei, Yizhen

2016-10-03

A continuous-wave microchip dual-frequency laser (DFL) with well balanced intensity was presented. In order to obtain such a balanced intensity distribution of the two frequency components, the DFL wavelengths were precisely tuned and spectrally matched with the emission cross section (ECS) spectrum of the gain medium by employing a temperature controller. Finally, when the heat sink temperature was controlled at -5.6°C, a 264 mW DFL signal was achieved with frequency separation at 67.52 GHz and intensity balance ratio (IBR) at 0.991.

Effect of balanced low pressure drying of curcuma longa leaf on skin immune activation activities.

PubMed

Choi, Wooseok; Lim, Hye Won; Lee, Hyeon Yong

2014-01-01

The effect of balanced low pressure drying pretreatment associated with ultrasonication extraction (BU) on the enhancement of skin immune modulatory activities of Curcuma longa leaf was studied by comparing with conventional hot air drying (HE), freeze drying (FE) and balanced low pressure drying (BE) pretreatment processes. In considering skin immune activation activities such as the inhibition of hyaluronidase activity, the BU extract showed ca. 10% higher than those of HE, and even higher than that of the FE extract. Nitric oxide production from macrophage of the BU extract in adding 1.0 mg/mL was increased up to 16.5 μM. When measuring inhibition of IL-6 and TNF-a production from the human T lymphocytes (T cell), the BU extract also showed 53% and 78% of inhibition effect, respectively. It is found that the BU extract could effectively suppress the expression levels of skin inflammation related genes such as Cox-2 and iNOS, down to 80% and 85% compared to the control, respectively. Balanced low pressure drying process was especially active on dehydration of the leaves with minimizing the destruction and making easier elution of the bioactive substances, which resulted in higher extraction yield and better biological activities.

Striking the right immunological balance prevents progression of tuberculosis.

PubMed

Vyas, Shachi Pranjal; Goswami, Ritobrata

2017-12-01

Tuberculosis (TB) caused by infection with Mycobacterium tuberculosis (Mtb) is a major burden for human health worldwide. Current standard treatments for TB require prolonged administration of antimycobacterial drugs leading to exaggerated inflammation and tissue damage. This can result in the reactivation of latent TB culminating in TB progression. Thus, there is an unmet need to develop therapies that would shorten the duration of anti-TB treatment and to induce optimal protective immune responses to control the spread of mycobacterial infection with minimal lung pathology. Granulomata is the hallmark structure formed by the organized accumulation of immune cells including macrophages, natural killer cells, dendritic cells, neutrophils, T cells, and B cells to the site of Mtb infection. It safeguards the host by containing Mtb in latent form. However, granulomata can undergo caseation and contribute to the reactivation of latent TB, if the immune responses developed to fight mycobacterial infection are not properly controlled. Thus, an optimal balance between innate and adaptive immune cells might play a vital role in containing mycobacteria in latent form for prolonged periods and prevent the spread of Mtb infection from one individual to another. Optimal and well-regulated immune responses against Mycobacterium tuberculosis may help to prevent the reactivation of latent TB. Moreover, therapies targeting balanced immune responses could help to improve treatment outcomes among latently infected TB patients and thereby limit the dissemination of mycobacterial infection.

Epigenome data release: a participant-centered approach to privacy protection.

PubMed

Dyke, Stephanie O M; Cheung, Warren A; Joly, Yann; Ammerpohl, Ole; Lutsik, Pavlo; Rothstein, Mark A; Caron, Maxime; Busche, Stephan; Bourque, Guillaume; Rönnblom, Lars; Flicek, Paul; Beck, Stephan; Hirst, Martin; Stunnenberg, Henk; Siebert, Reiner; Walter, Jörn; Pastinen, Tomi

2015-07-17

Large-scale epigenome mapping by the NIH Roadmap Epigenomics Project, the ENCODE Consortium and the International Human Epigenome Consortium (IHEC) produces genome-wide DNA methylation data at one base-pair resolution. We examine how such data can be made open-access while balancing appropriate interpretation and genomic privacy. We propose guidelines for data release that both reduce ambiguity in the interpretation of open-access data and limit immediate access to genetic variation data that are made available through controlled access.

JPRS Report, Science & Technology USSR: Space Biology & Aerospace Medicine, Vol. 22, No. 1, January-February 1988

DTIC Science & Technology

1988-06-23

belief that resistance of the system that controls human movements to the disrupting effect of rhythmic photostimulation is determined by the capacity...No strict correlation between the negative balance of calcium and mineral content in leg compact bones and foot spongy bones was found. There was a...In terms of negative and positive trends leg and foot bones were in better condition in the drug group. The techniques used were assessed with

False Balance in Climate Change Reporting Among TV Meteorologists

NASA Astrophysics Data System (ADS)

Timm, K.; Maibach, E.; Boykoff, M.; Broeckelman-Post, M.; Myers, T.; Perkins, D. R., IV

2017-12-01

False balance is the journalistic practice of giving equal weight to both sides of a story, regardless of an established truth and validity on one side. Despite widespread scientific agreement about the anthropogenic causes of climate change, false balance on the subject of climate change remains common in television despite a documented decline in other media. In this exploratory study, 452 American TV meteorologists were surveyed about their climate change beliefs and asked how often and why they present an opposing viewpoint when they present about human contributions to climate change. The results indicate that this practice is fairly common, with nearly 30% of TV meteorologists presenting an opposing viewpoint at least half the time or more frequently when they present about climate change. Weathercasters described including an opposing viewpoint in their stories for many different reasons, including that it is essential to objective and balanced reporting, that it is used to acknowledge different audience viewpoints, and because the science is perceived to be uncertain. The results also suggest that being more certain that climate change is happening, that it is primarily caused by humans, and perceiving the full extent of the scientific consensus about human-caused climate change, are associated with decreased frequency of presenting an opposing viewpoint. This is the first time the issue of false balance has been studied in the context of TV weathercasters, and while more research is needed, these results provide some preliminary evidence to suggest that increasing weathercasters' understanding of the scientific consensus of human caused climate change may help reduce false balance reporting. Furthermore, as meteorologists and weathercasters become more prominent reporters of local climate news, it will be important for them to have techniques to accurately report the science, while maintaining their sense of objectivity.

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CALIBRATION AND OPERATION OF BALANCES (UA-L-1.2)

EPA Science Inventory

The purpose of this SOP is to describe the procedures used when calibrating and operating balances during the Arizona NHEXAS project and the "Border" study. Keywords: lab; equipment; balances.

The National Human Exposure Assessment Survey (NHEXAS) is a federal interagency rese...

Fall prevention in the young old using an exoskeleton human body posturizer: a randomized controlled trial.

PubMed

Verrusio, W; Gianturco, V; Cacciafesta, M; Marigliano, V; Troisi, G; Ripani, M

2017-04-01

Fall risk in elderly has been related with physical decline, low quality of life and reduced survival. To evaluate the impact of exoskeleton human body posturizer (HBP) on the fall risk in the elderly. 150 subjects (mean age 64.85; 79 M/71 F) with mild fall risk were randomized into two groups: 75 for group treated with human body posturizer (HBP group) and 75 for physical training without HBP group (exercise group). The effects of interventions were assessed by differences in tests related to balance and falls. Medically eligible patients were screened with Tinetti balance and Gait evaluation scale, short physical performance battery and numeric pain rating scale to determine fall risk in elderly people. In the HBP group there was a significant improvement in short physical performance battery, Tinetti scale and Pain Numeric rating scale with a significant reduction in fall risk (p < 0.05). In the exercise group we observed only minimal variations in the test scores. The results at the sixth and twelfth months show a twofold positive effect in the HBP group reducing fall risk and improving quality of life by reducing pain. The use of exoskeleton human body posturizer seems to be a new significant device for prevention of fall in elderly patients. Further research should be carried out to obtain more evidence on effects of robotic technology for fall prevention in the elderly.

A balance of activity in brain control and reward systems predicts self-regulatory outcomes

PubMed Central

Chen, Pin-Hao A.; Huckins, Jeremy F.; Hofmann, Wilhelm; Kelley, William M.; Heatherton, Todd F.

2017-01-01

Abstract Previous neuroimaging work has shown that increased reward-related activity following exposure to food cues is predictive of self-control failure. The balance model suggests that self-regulation failures result from an imbalance in reward and executive control mechanisms. However, an open question is whether the relative balance of activity in brain systems associated with executive control (vs reward) supports self-regulatory outcomes when people encounter tempting cues in daily life. Sixty-nine chronic dieters, a population known for frequent lapses in self-control, completed a food cue-reactivity task during an fMRI scanning session, followed by a weeklong sampling of daily eating behaviors via ecological momentary assessment. We related participants’ food cue activity in brain systems associated with executive control and reward to real-world eating patterns. Specifically, a balance score representing the amount of activity in brain regions associated with self-regulatory control, relative to automatic reward-related activity, predicted dieters’ control over their eating behavior during the following week. This balance measure may reflect individual self-control capacity and be useful for examining self-regulation success in other domains and populations. PMID:28158874

A balance of activity in brain control and reward systems predicts self-regulatory outcomes.

PubMed

Lopez, Richard B; Chen, Pin-Hao A; Huckins, Jeremy F; Hofmann, Wilhelm; Kelley, William M; Heatherton, Todd F

2017-05-01

Previous neuroimaging work has shown that increased reward-related activity following exposure to food cues is predictive of self-control failure. The balance model suggests that self-regulation failures result from an imbalance in reward and executive control mechanisms. However, an open question is whether the relative balance of activity in brain systems associated with executive control (vs reward) supports self-regulatory outcomes when people encounter tempting cues in daily life. Sixty-nine chronic dieters, a population known for frequent lapses in self-control, completed a food cue-reactivity task during an fMRI scanning session, followed by a weeklong sampling of daily eating behaviors via ecological momentary assessment. We related participants' food cue activity in brain systems associated with executive control and reward to real-world eating patterns. Specifically, a balance score representing the amount of activity in brain regions associated with self-regulatory control, relative to automatic reward-related activity, predicted dieters' control over their eating behavior during the following week. This balance measure may reflect individual self-control capacity and be useful for examining self-regulation success in other domains and populations. © The Author (2017). Published by Oxford University Press.

Falls prevention and balance rehabilitation in multiple sclerosis: a bi-centre randomised controlled trial.

PubMed

Cattaneo, Davide; Rasova, Kamila; Gervasoni, Elisa; Dobrovodská, Gabriela; Montesano, Angelo; Jonsdottir, Johanna

2018-03-01

People with Multiple Sclerosis (PwMS) have a high incidence of accidental falls that have a potentially detrimental effect on their daily life participation. The effect of balance specific rehabilitation on clinical balance measures and frequency of falls in PwMS was studied. A bi-centre randomised rater-blinded controlled trial. Participants in both groups received 20 treatment sessions. Participants in the intervention group received treatment aimed at improving balance and mobility. Participants in the control group received treatments to reduce limitations at activity and body function level. Primary measures were frequency of fallers (>1 fall in two months) and responders (>3 points improvement) at the Berg Balance Scale (BBS). Data was analysed according to an intention to treat approach. One hundred and nineteen participants were randomised. Following treatment frequency of fallers was 22% in the intervention group and 23% in the control group, odds ratio (OR) and (confidence limits): 1.05 (0.41 to 2.77). Responders on the BBS were 28% in the intervention group and 33% in the control group, OR = 0.75 (0.30 to 1.91). At follow up ORs for fallers and responders at BBS were 0.98 (0.48 to 2.01) and 0.79 (0.26 to 2.42), respectively. Twenty sessions 2-3 times/week of balance specific rehabilitation did not reduce fall frequency nor improve balance suggesting the need for more frequent and challenging interventions. Implications for Rehabilitation Programs for balance rehabilitation can improve balance but their effects in fall prevention are unclear. Twenty treatments sessions 2/3 times per week did not reduced frequency of falls in MS. The comparison with similar studies suggests that higher intensity of practice of highly challenging balance activities appears to be critical to maximizing effectiveness.

Balance Training Enhances Motor Coordination During a Perturbed Sidestep Cutting Task.

PubMed

Oliveira, Anderson Souza; Silva, Priscila Brito; Lund, Morten Enemark; Farina, Dario; Kersting, Uwe Gustav

2017-11-01

Study Design Controlled laboratory study. Background Balance training may improve motor coordination. However, little is known about the changes in motor coordination during unexpected perturbations to postural control following balance training. Objectives To study the effects of balance training on motor coordination and knee mechanics during perturbed sidestep cutting maneuvers in healthy adults. Methods Twenty-six healthy men were randomly assigned to a training group or a control group. Before balance training, subjects performed unperturbed, 90° sidestep cutting maneuvers and 1 unexpected perturbed cut (10-cm translation of a movable platform). Participants in the training group participated in a 6-week balance training program, while those in the control group followed their regular activity schedule. Both groups were retested after a 6-week period. Surface electromyography was recorded from 16 muscles of the supporting limb and trunk, as well as kinematics and ground reaction forces. Motor modules were extracted from electromyography by nonnegative matrix factorization. External knee abduction moments were calculated using inverse dynamics equations. Results Balance training reduced the external knee abduction moment (33% ± 25%, P<.03, η p 2 = 0.725) and increased the activation of trunk and proximal hip muscles in specific motor modules during perturbed cutting. Balance training also increased burst duration for the motor module related to landing early in the perturbation phase (23% ± 11%, P<.01, η p 2 = 0.532). Conclusion Balance training resulted in altered motor coordination and a reduction in knee abduction moment during an unexpected perturbation. The previously reported reduction in injury incidence following balance training may be linked to changes in dynamic postural stability and modular neuromuscular control. J Orthop Sports Phys Ther 2017;47(11):853-862. Epub 23 Sep 2017. doi:10.2519/jospt.2017.6980.

How Building Systems Affect Worker Wellness

DTIC Science & Technology

1994-03-01

spatial configuration must strike a balance between the objective needs of the organization and the more subjective human ingredient. Good building...sense, building design for thermal comfort involves a balance between the building’s orientation, its windowing scheme, the use of thermal mass, and the...stated above. An improved quality of worklife and a humanized work environment are psychological incentives that can increase productivity. Worker specific

Acclimatization to heat in humans

NASA Technical Reports Server (NTRS)

Greenleaf, John E.; Kaciuba-Uscilko, Hanna

1989-01-01

The responses and mechanisms of both natural and artificial acclimatization to a hot environment in mammals are addressed with specific reference to humans. The purpose is to provide basic information for designers of thermal protection systems and countermeasures for astronauts during intra- and extravehicular activity. Areas covered are energy metabolism, thermal balance at rest and during exercise, water and electrolyte balance during exercise and immobilization, and heat diseases.

Feasibility of Wii Fit training to improve clinical measures of balance in older adults.

PubMed

Bieryla, Kathleen A; Dold, Neil M

2013-01-01

Numerous interventions have been proposed to improve balance in older adults with varying degrees of success. A novel approach may be to use an off-the-shelf video game system utilizing real-time force feedback to train older adults. The purpose of this study is to investigate the feasibility of using Nintendo's Wii Fit for training to improve clinical measures of balance in older adults and to retain the improvements after a period of time. Twelve healthy older adults (aged >70 years) were randomly divided into two groups. The experimental group completed training using Nintendo's Wii Fit game three times a week for 3 weeks while the control group continued with normal activities. Four clinical measures of balance were assessed before training, 1 week after training, and 1 month after training: Berg Balance Scale (BBS), Fullerton Advanced Balance (FAB) scale, Functional Reach (FR), and Timed Up and Go (TUG). Friedman two-way analysis of variance by ranks was conducted on the control and experimental group to determine if training using the Wii Balance Board with Wii Fit had an influence on clinical measures of balance. Nine older adults completed the study (experimental group n = 4, control group n = 5). The experimental group significantly increased their BBS after training while the control group did not. There was no significant change for either group with FAB, FR, and TUG. Balance training with Nintendo's Wii Fit may be a novel way for older adults to improve balance as measured by the BBS.

Determinants of sport-specific postural control strategy and balance performance of amateur rugby players.

PubMed

Chow, Gary C C; Fong, Shirley S M; Chung, Joanne W Y; Chung, Louisa M Y; Ma, Ada W W; Macfarlane, Duncan J

2016-11-01

Postural control strategy and balance performance of rugby players are important yet under-examined issues. This study aimed to examine the differences in balance strategy and balance performance between amateur rugby players and non-players, and to explore training- and injury-related factors that may affect rugby players' balance outcomes. Cross-sectional and exploratory study. Forty-five amateur rugby players and 41 healthy active individuals participated in the study. Balance performance and balance strategies were assessed using the sensory organization test (SOT) of the Smart Equitest computerized dynamic posturography machine. Rugby training history and injury history were solicited from the participants. The SOT strategy scores were 1.99-54.90% lower in the rugby group than in the control group (p<0.05), and the equilibrium scores were 1.06-14.29% lower in the rugby group than in the control group (p<0.05). After accounting for age, sex and body mass index, only length of rugby training (in years) was independently associated with the SOT condition 6 strategy score, explaining 15.7% of its variance (p=0.006). There was no association between SOT condition 6 strategy/equilibrium scores and injury history among the rugby players (p>0.05). Amateur rugby players demonstrated inferior balance strategy and balance performance compared to their non-training counterparts. Their suboptimal balance strategy was associated with insufficient training experience but not with history of injury. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

A dual-task home-based rehabilitation programme for improving balance control in patients with acquired brain injury: a single-blind, randomized controlled pilot study.

PubMed

Peirone, Eliana; Goria, Paolo Filiberto; Anselmino, Arianna

2014-04-01

To evaluate the safety, feasibility and effectiveness of a dual-task home-based rehabilitation programme on balance impairments among adult patients with acquired brain injury. Single-blind, randomized controlled pilot study. Single rehabilitation centre. Sixteen participants between 12 and 18 months post-acquired brain injury with balance impairments and a score <10 seconds on the One-Leg Stance Test (eyes open). All participants received 50-minutes individualised traditional physiotherapy sessions three times a week for seven weeks. In addition, the intervention group (N = 8) performed an individualised dual-task home-based programme six days a week for seven weeks. The primary outcome measure was the Balance Evaluation System Test; secondary measures were the Activities-specific Balance Confidence Scale and Goal Attainment Scaling. At the end of the pilot study, the intervention group showed significantly greater improvement in Balance Evaluation System Test scores (17.87, SD 6.05) vs. the control group (5.5, SD 3.53; P = 0.008, r = 0.63). There was no significant difference in improvement in Activities-specific Balance Confidence Scale scores between the intervention group (25.25, SD 25.51) and the control group (7.00, SD 14.73; P = 0.11, r = 0.63). There was no significant improvement in Goal Attainment Scaling scores in the intervention (19.37, SD 9.03) vs. the control group (16.28, SD 6.58; P = 0.093, r = 0.63). This pilot study shows the safety, feasibility and short-term benefit of a dual-task home-based rehabilitation programme to improve balance control in patients with acquired brain injury. A sample size of 26 participants is required for a definitive study.

The influence of Pilates exercises on body balance in the standing position of hearing impaired people.

PubMed

Walowska, Jagoda; Bolach, Bartosz; Bolach, Eugeniusz

2017-11-13

Hearing impairment may affect the body posture maintenance. The aim of the study was to evaluate the effect of modified Pilates exercise program on the body posture maintenance in hearing impaired people. Eighty students (aged 13-24) were enrolled and randomly allocated into two groups: test group (n = 41) which attended an original program based on modified Pilates exercises and control group (n = 39) which attended standard physical education classes. Stabilographic tests were conducted at baseline and after 6-week training program. Both groups showed improved control of body balance in a standing position manifested in reductions of the length of path, surface area, and speed of deflection. Modified Pilates program was significantly more effective in improving body balance control in relaxed posture and with feet together than standard physical education classes. The greater efficiency of the modified Pilates program was expressed in a significant improvement in balance control parameters, i.e., path length, surface area, and speed of deflection. The modified Pilates program was more effective in improving body balance control in the hearing impaired people than standard physical education classes. Modification of physical activity recommendations for hearing impaired students may be considered; however, further research is required. Implications for Rehabilitation Hearing impairment impacts the mental, social and, physical spheres of life as well as deteriorates equivalent reactions and the way body posture is maintained. In hearing impaired people, control of body balance and muscle coordination is often disturbed, thus more attention should be paid to exercises associated with balance which may improve the ability to learn and develop motor skills. Modified Pilates program was significantly more effective in improving body balance control than standard physical education classes in hearing impaired people.

Bone Balance within a Cortical BMU: Local Controls of Bone Resorption and Formation

PubMed Central

Smith, David W.; Gardiner, Bruce S.; Dunstan, Colin

2012-01-01

Maintaining bone volume during bone turnover by a BMU is known as bone balance. Balance is required to maintain structural integrity of the bone and is often dysregulated in disease. Consequently, understanding how a BMU controls bone balance is of considerable interest. This paper develops a methodology for identifying potential balance controls within a single cortical BMU. The theoretical framework developed offers the possibility of a directed search for biological processes compatible with the constraints of balance control. We first derive general control constraint equations and then introduce constitutive equations to identify potential control processes that link key variables that describe the state of the BMU. The paper describes specific local bone volume balance controls that may be associated with bone resorption and bone formation. Because bone resorption and formation both involve averaging over time, short-term fluctuations in the environment are removed, leaving the control systems to manage deviations in longer-term trends back towards their desired values. The length of time for averaging is much greater for bone formation than for bone resorption, which enables more filtering of variability in the bone formation environment. Remarkably, the duration for averaging of bone formation may also grow to control deviations in long-term trends of bone formation. Providing there is sufficient bone formation capacity by osteoblasts, this leads to an extraordinarily robust control mechanism that is independent of either osteoblast number or the cellular osteoid formation rate. A complex picture begins to emerge for the control of bone volume. Different control relationships may achieve the same objective, and the ‘integration of information’ occurring within a BMU may be interpreted as different sets of BMU control systems coming to the fore as different information is supplied to the BMU, which in turn leads to different observable BMU behaviors. PMID:22844401

Effectuation of adaptive stability and postural alignment strategies are decreased by alcohol intoxication.

PubMed

Hafström, A; Modig, F; Magnusson, M; Fransson, P A

2014-06-01

Human stability control is a complex process comprising contributions from several partly independent mechanisms such as coordination, feedback and feed-forward control, and adaptation. Acute alcohol intoxication impairs these functions and is recognized as a major contributor to fall traumas. The study aimed to investigate how alcohol intoxication at .06% and .10% blood alcohol concentration (BAC) affected the movement spans and control of posture alignment. The angular positions of the head, shoulder, hip and knees relative to the ankles were measured with a 3D motion analysis system in 25 healthy adults during standing with eyes open or closed and with or without vibratory balance perturbations. Alcohol intoxication significantly increased the movement spans of the head, shoulders, hip and knees in anteroposterior and lateral directions during quiet stance (p < or = .047 and p < or = .003) and balance perturbations (p<.001, both directions). Alcohol intoxication also decreased the ability to reduce the movement spans through adaptation in both anteroposterior (p < or = .011) and lateral (p < or = .004) directions. When sober and submitted to balance perturbations, the subjects aligned the head, shoulders, hip and knees more forward relative to the ankle joint (p < .001), hence adopting a more resilient posture increasing the safety margin for backward falls. Alcohol intoxication significantly delayed this forward realignment (p < or = .022). Alcohol intoxication did not cause any significant posture realignment in the lateral direction. Thus, initiation of adaptive posture realignments to alcohol or other disruptions might be context dependent and associated with reaching a certain level of stability threats. Copyright © 2014 Elsevier B.V. All rights reserved.

Dorsomedial striatum involvement in regulating conflict between current and presumed outcomes.

PubMed

Mestres-Missé, Anna; Bazin, Pierre-Louis; Trampel, Robert; Turner, Robert; Kotz, Sonja A

2014-09-01

The balance between automatic and controlled processing is essential to human flexible but optimal behavior. On the one hand, the automation of habitual behavior and processing is indispensable, and, on the other hand, strategic processing is needed in light of unexpected, conflicting, or new situations. Using ultra-high-field high-resolution functional magnetic resonance imaging (7T-fMRI), the present study examined the role of subcortical structures in mediating this balance. Participants were asked to judge the congruency of sentences containing a semantically ambiguous or unambiguous word. Ambiguous sentences had three possible resolutions: dominant meaning, subordinate meaning, and incongruent. The dominant interpretation represents the most habitual response, whereas both the subordinate and incongruent options clash with this automatic response, and, hence, require cognitive control. Moreover, the subordinate resolution entails a less expected but correct outcome, while the incongruent condition is simply wrong. The current results reveal the involvement of the anterior dorsomedial striatum in modulating and resolving conflict between actual and expected outcomes, and highlight the importance of cortical and subcortical cooperation in this process. Copyright © 2014 Elsevier Inc. All rights reserved.

Postural control in elderly persons with osteoporosis: Efficacy of an intervention program to improve balance and muscle strength: a randomized controlled trial.

PubMed

Burke, Thomaz Nogueira; França, Fábio Jorge Renovato; Ferreira de Meneses, Sarah Rúbia; Cardoso, Viviam Inhasz; Marques, Amélia Pasqual

2010-07-01

To assess the efficacy of an exercise program aiming to improve balance and muscular strength, for postural control and muscular strength of women with osteoporosis. Sample consisted of 33 women with osteoporosis, randomized into one of two groups: intervention group, in which exercises for balance and improvement of muscular strength of the inferior members were performed for 8 wks (n = 17, age 72.8 +/- 3.6 yrs); control group, which was women not practicing exercises (n = 16, age 74.4 +/- 3.7 yrs). At baseline and after 8 wks of treatment, postural control was assessed using a force plate (Balance Master, Neurocom), and muscular strength during ankle dorsiflexion, knee extension, and flexion was assessed by dynamometry. Adherence to the program was 82%. When compared with the control group, individuals in the intervention group significantly improved the center of pressure velocity (P = 0.02) in the modified clinical test of sensory interaction for balance test, center of pressure velocity (P < 0.01), and directional control (P < 0.01) in limits of stability test, isometric force during ankle dorsiflexion (P = 0.01), knee extension (P < 0.01), and knee flexion (P < 0.01). Balance and strength exercises are effective in improving postural control and lower-limb strength in elderly women with osteoporosis.

Children with ADHD Show No Deficits in Plantar Foot Sensitivity and Static Balance Compared to Healthy Controls

ERIC Educational Resources Information Center

Schlee, Gunther; Neubert, Tom; Worenz, Andreas; Milani, Thomas L.

2012-01-01

The goal of this study was to investigate plantar foot sensitivity and balance control of ADHD (n = 21) impaired children compared to age-matched healthy controls (n = 25). Thresholds were measured at 200 Hz at three anatomical locations of the plantar foot area of both feet (hallux, first metatarsal head (METI) and heel). Body balance was…

Balance Training Enhances Vestibular Function and Reduces Overactive Proprioceptive Feedback in Elderly

PubMed Central

Wiesmeier, Isabella K.; Dalin, Daniela; Wehrle, Anja; Granacher, Urs; Muehlbauer, Thomas; Dietterle, Joerg; Weiller, Cornelius; Gollhofer, Albert; Maurer, Christoph

2017-01-01

Objectives: Postural control in elderly people is impaired by degradations of sensory, motor, and higher-level adaptive mechanisms. Here, we characterize the effects of a progressive balance training program on these postural control impairments using a brain network model based on system identification techniques. Methods and Material: We analyzed postural control of 35 healthy elderly subjects and compared findings to data from 35 healthy young volunteers. Eighteen elderly subjects performed a 10 week balance training conducted twice per week. Balance training was carried out in static and dynamic movement states, on support surfaces with different elastic compliances, under different visual conditions and motor tasks. Postural control was characterized by spontaneous sway and postural reactions to pseudorandom anterior-posterior tilts of the support surface. Data were interpreted using a parameter identification procedure based on a brain network model. Results: With balance training, the elderly subjects significantly reduced their overly large postural reactions and approximated those of younger subjects. Less significant differences between elderly and young subjects' postural control, namely larger spontaneous sway amplitudes, velocities, and frequencies, larger overall time delays and a weaker motor feedback compared to young subjects were not significantly affected by the balance training. Conclusion: Balance training reduced overactive proprioceptive feedback and restored vestibular orientation in elderly. Based on the assumption of a linear deterioration of postural control across the life span, the training effect can be extrapolated as a juvenescence of 10 years. This study points to a considerable benefit of a continuous balance training in elderly, even without any sensorimotor deficits. PMID:28848430

Recalibrating disparities in perceived and actual balance abilities in older adults: a mixed-methods evaluation of a novel exergaming intervention.

PubMed

Ellmers, Toby J; Paraskevopoulos, Ioannis Th; Williams, A Mark; Young, William R

2018-03-22

Published reports suggest a disparity between perceived and actual balance abilities, a trait associated with increased fall-risk in older adults. We investigate whether it is possible to 'recalibrate' these disparities using a novel gaming intervention. We recruited 26 older adults for a 4-week intervention in which they participated in 8-sessions using a novel gaming intervention designed to provide explicit, augmented feedback related to postural control. Measures of perceived balance abilities (Falls Efficacy Scale-International) and actual postural control (limits of stability) were assessed pre- and post-intervention. We used focus groups to elicit the opinions of participants about how the game may have influenced balance abilities and confidence. A stronger alignment was observed between postural control and perceived balance capabilities post-intervention (i.e., significant correlations between Falls Efficacy Scale-International scores and limits of stability which were not present pre-intervention). Also, significant improvements in measures of postural control were observed, with these improvements confined to the aspects of postural control for which the exergame provided explicit, augmented feedback. Qualitative data revealed that the intervention made participants more "aware" of their balance abilities. Our results demonstrate that it is possible to recalibrate the perceptions of older adults relating to their balance abilities through a targeted, short-term intervention. We propose that the post-intervention improvements in postural control may have been, in part, the result of this recalibration; with altered perceptions leading to changes in balance performance. Findings support the application of novel interventions aimed at addressing the psychological factors associated with elderly falls.

Bilateral Improvements in Lower Extremity Function After Unilateral Balance Training in Individuals With Chronic Ankle Instability

PubMed Central

Hale, Sheri A.; Fergus, Andrea; Axmacher, Rachel; Kiser, Kimberly

2014-01-01

Context: Bilateral improvements in postural control have been reported among individuals with acute lateral ankle sprains and individuals with chronic ankle instability (CAI) when only the unstable ankle is rehabilitated. We do not know if training the stable ankle will improve function on the unstable side. Objective: To explore the effects of a unilateral balance-training program on bilateral lower extremity balance and function in individuals with CAI when only the stable limb is trained. Design: Cohort study. Setting: University clinical research laboratory. Patients or Other Participants: A total of 34 volunteers (8 men, 26 women; age = 24.32 ± 4.95 years, height = 167.01 ± 9.45 cm, mass = 77.54 ± 23.76 kg) with CAI were assigned to the rehabilitation (n = 17) or control (n = 17) group. Of those, 27 (13 rehabilitation group, 14 control group) completed the study. Intervention(s): Balance training twice weekly for 4 weeks. Main Outcome Measure(s): Foot and Ankle Disability Index (FADI), FADI Sport (FADI-S), Star Excursion Balance Test, and Balance Error Scoring System. Results: The rehabilitation and control groups differed in changes in FADI-S and Star Excursion Balance Test scores over time. Only the rehabilitation group improved in the FADI-S and in the posteromedial and anterior reaches of the Star Excursion Balance Test. Both groups demonstrated improvements in posterolateral reach; however, the rehabilitation group demonstrated greater improvement than the control group. When the groups were combined, participants reported improvements in FADI and FADI-S scores for the unstable ankle but not the stable ankle. Conclusions: Our data suggest training the stable ankle may result in improvements in balance and lower extremity function in the unstable ankle. This further supports the existence of a centrally mediated mechanism in the development of postural-control deficits after injury, as well as improved postural control after rehabilitation. PMID:24568231

The consequence of phototherapy exposure on oxidative stress status of expressed human milk.

PubMed

Unal, Sezin; Demirel, Nihal; Yaprak Sul, Deniz; Ulubas Isik, Dilek; Erol, Sara; Neselioglu, Salim; Erel, Ozcan; Bas, Ahmet Yagmur

2017-09-04

There exists evidence that phototherapy can disturb the oxidant/antioxidant balance in favor of oxidants. If phototherapy is continued during tube feeding in preterms, expressed human milk is subjected to phototherapy lights for about 20 min per feeding. We aimed to investigate the effects of phototherapy lights on oxidative/antioxidative status of expressed human milk. Milk samples of 50 healthy mothers were grouped as control and phototherapy and exposed to 20 min of day-light and phototherapy light, respectively. Total antioxidant capacity (mmol-Trolox equiv/L) and total oxidant status (mmol-H 2 O 2 /L) in expressed human milk samples were measured. Levels of antioxidant capacity of the expressed human milks in the phototherapy group were lower than those of the control group [mmol-Trolox equiv/L; median (interquartile-range): 1.30 (0.89-1.65) and 1.77 (1.51-2.06), p: < .001]. Levels of oxidant status were similar in both groups. We demonstrated that phototherapy decreased antioxidant capacity of expressed human milk without any alteration in oxidative status. We think that this observation is important for the care of very low birth weighted infants who have limited antioxidant capacity and are vulnerable to oxidative stress. It may be advisable either to turn off the phototherapy or cover the tube and syringe to preserve antioxidant capacity of human milk during simultaneous tube feeding and phototherapy treatment.

Static and Functional Balance in Individuals With COPD: Comparison With Healthy Controls and Differences According to Sex and Disease Severity.

PubMed

de Castro, Larissa A; Ribeiro, Laís Rg; Mesquita, Rafael; de Carvalho, Débora R; Felcar, Josiane M; Merli, Myriam F; Fernandes, Karen Bp; da Silva, Rubens A; Teixeira, Denilson C; Spruit, Martijn A; Pitta, Fabio; Probst, Vanessa S

2016-11-01

Studies have shown that individuals with COPD have impaired body balance, probably caused by the disease's multisystemic manifestations plus age-related decline in balance, potentially increasing the risk of falling and its consequences. However, little is known about the profile of individuals with COPD who present balance impairments, especially related to sex and disease severity stages. The aim of this work was to compare static and functional balance between subjects with COPD and healthy controls and to check possible differences according to sex and degrees of disease severity. Forty-seven subjects with COPD and 25 healthy controls were included in this study. Their static balance was assessed in one-legged stance using a force platform and functional balance with the Timed Up and Go test. Additionally, participants performed spirometry, the 6-min walk test and isometric quadriceps maximal voluntary contraction assessment. Disease severity was classified according to the Global Initiative for Obstructive Lung Disease stages and BODE (body mass index, air-flow obstruction, dyspnea, and exercise capacity) scores. In comparison with healthy controls, subjects with COPD had worse static (center of pressure displacement area: 9.3 ± 1.9 cm 2 vs 11.6 ± 4.0 cm 2 , respectively, P = .01) and functional balance (Timed Up and Go test: 8.5 ± 1.3 s vs 10.3 ± 1.8 s, respectively, P < .001). In the COPD group, men performed better in the Timed Up and Go test than women (9.8 ± 1.2 s vs 10.9 ± 2.2 s, respectively, P = .03), whereas women presented a better static balance in comparison with men for all parameters related to center of pressure (P < .005 for all). Disease severity did not affect any balance results. Individuals with COPD had worse static and functional balance in comparison with healthy controls. Sex can mediate these results, depending on the type of balance evaluation (force platform or functional test). Balance performance was similar among the groups classified according to disease severity. Copyright © 2016 by Daedalus Enterprises.

Balance Training With a Dynamometric Platform Following Total Knee Replacement: A Randomized Controlled Trial.

PubMed

Roig-Casasús, Sergio; María Blasco, José; López-Bueno, Laura; Blasco-Igual, María Clara

2017-03-01

Sensorimotor training has proven to be an efficient approach for recovering balance control following total knee replacement (TKR). The purpose of this trial was to evaluate the influence of specific balance-targeted training using a dynamometric platform on the overall state of balance in older adults undergoing TKR. This was a randomized controlled clinical trial conducted at a university hospital rehabilitation unit. Patients meeting the inclusion criteria were randomly assigned to a control group or an experimental group. Both groups participated in the same 4-week postoperative rehabilitation training protocol. Participants in the experimental group performed additional balance training with a dynamometric platform consisting of tests related to stability challenges, weight-shifting, and moving to the limits of stability. The primary outcome measure was the overall state of balance rated according to the Berg Balance Scale. Secondary outcomes in terms of balance were the Timed Up and Go Test, Functional Reach Test, and Romberg open and closed-eyes tests. Data processing included between-group analysis of covariance, minimal detectable change assessment for the primary outcome measure, and effect size estimation. Confidence intervals (CIs) were set at 95%. Forty-three participants meeting the inclusion criteria and having signed the informed consent were randomly assigned to 2 groups. Thirty-seven completed the training (86.1%). Significant between-group differences in balance performance were found as measured with the Berg Balance Scale (P = .03) and Functional Reach Test (P = .04) with a CI = 95%. Significant differences were not recorded for the Timed Up and Go Test or Romberg open and closed-eyes tests (P > .05). Furthermore, Cohen's effect size resulted in a value of d = 0.97, suggesting a high practical significance of the trial. According to the Berg Balance Scale and Functional Reach Test, participants with TKR who have followed a 4-week training program using a dynamometric platform improved balance performance to a higher extent than a control group training without such a device. The inclusion of this instrument in the functional training protocol may be beneficial for recovering balance following TKR.

Balance Training Reduces Brain Activity during Motor Simulation of a Challenging Balance Task in Older Adults: An fMRI Study

PubMed Central

Ruffieux, Jan; Mouthon, Audrey; Keller, Martin; Mouthon, Michaël; Annoni, Jean-Marie; Taube, Wolfgang

2018-01-01

Aging is associated with a shift from an automatic to a more cortical postural control strategy, which goes along with deteriorations in postural stability. Although balance training has been shown to effectively counteract these behavioral deteriorations, little is known about the effect of balance training on brain activity during postural tasks in older adults. We, therefore, assessed postural stability and brain activity using fMRI during motor imagery alone (MI) and in combination with action observation (AO; i.e., AO+MI) of a challenging balance task in older adults before and after 5 weeks of balance training. Results showed a nonsignificant trend toward improvements in postural stability after balance training, accompanied by reductions in brain activity during AO+MI of the balance task in areas relevant for postural control, which have been shown to be over-activated in older adults during (simulation of) motor performance, including motor, premotor, and multisensory vestibular areas. This suggests that balance training may reverse the age-related cortical over-activations and lead to changes in the control of upright posture toward the one observed in young adults. PMID:29472847

Balance Training Reduces Brain Activity during Motor Simulation of a Challenging Balance Task in Older Adults: An fMRI Study.

PubMed

Ruffieux, Jan; Mouthon, Audrey; Keller, Martin; Mouthon, Michaël; Annoni, Jean-Marie; Taube, Wolfgang

2018-01-01

Aging is associated with a shift from an automatic to a more cortical postural control strategy, which goes along with deteriorations in postural stability. Although balance training has been shown to effectively counteract these behavioral deteriorations, little is known about the effect of balance training on brain activity during postural tasks in older adults. We, therefore, assessed postural stability and brain activity using fMRI during motor imagery alone (MI) and in combination with action observation (AO; i.e., AO+MI) of a challenging balance task in older adults before and after 5 weeks of balance training. Results showed a nonsignificant trend toward improvements in postural stability after balance training, accompanied by reductions in brain activity during AO+MI of the balance task in areas relevant for postural control, which have been shown to be over-activated in older adults during (simulation of) motor performance, including motor, premotor, and multisensory vestibular areas. This suggests that balance training may reverse the age-related cortical over-activations and lead to changes in the control of upright posture toward the one observed in young adults.

Application of digital control to a magnetic model suspension and balance model

NASA Technical Reports Server (NTRS)

Luh, P. B.; Covert, E. E.; Whitaker, H. P.; Haldeman, C. W.

1978-01-01

The feasibility of using a digital computer for performing the automatic control functions for a magnetic suspension and balance system (MSBS) for use with wind tunnel models was investigated. Modeling was done using both a prototype MSBS and a one dimensional magnetic balance. A microcomputer using the Intel 8080 microprocessor is described and results are given using this microprocessor to control the one dimensional balance. Hybrid simulations for one degree of freedom of the MSBS were also performed and are reported. It is concluded that use of a digital computer to control the MSBS is eminently feasible and should extend both the accuracy and utility of the system.

Active video gaming to improve balance in the elderly.

PubMed

Lamoth, Claudine J C; Caljouw, Simone R; Postema, Klaas

2011-01-01

The combination of active video gaming and exercise (exergaming) is suggested to improve elderly people's balance, thereby decreasing fall risk. Exergaming has been shown to increase motivation during exercise therapy, due to the enjoyable and challenging nature, which could support long-term adherence for exercising balance. However, scarce evidence is available of the direct effects of exergaming on postural control. Therefore, the aim of the study was to assess the effect of a six-week videogame-based exercise program aimed at improving balance in elderly people. Task performance and postural control were examined using an interrupted time series design. Results of multilevel analyses showed that performance on the dot task improved within the first two weeks of training. Postural control improved during the intervention. After the intervention period task performance and balance were better than before the intervention. Results of this study show that healthy elderly can benefit from a videogame-based exercise program to improve balance and that all subjects were highly motivated to exercise balance because they found gaming challenging and enjoyable.

The effects of pilates on balance, mobility and strength in patients with multiple sclerosis.

PubMed

Guclu-Gunduz, Arzu; Citaker, Seyit; Irkec, Ceyla; Nazliel, Bijen; Batur-Caglayan, Hale Zeynep

2014-01-01

Although there are evidences as to Pilates developing dynamic balance, muscle strength and flexibility in healthy people, evidences related to its effects on Multiple Sclerosis patients are insufficient. The aims of this study were to investigate the effects of Pilates on balance, mobility, and strength in ambulatory patients with Multiple Sclerosis. Twenty six patients were divided into two groups as experimental (n = 18) and control (n = 8) groups for an 8-week treatment program. The experimental group underwent Pilates and the control group did abdominal breathing and active extremity exercises at home. Balance and mobility were measured with Berg Balance Scale and Timed up and go test, upper and lower muscle strength with hand-held dynamometer. Confidence in balance skills while performing daily activities was evaluated with Activities Specific Balance Confidence Scale. Improvements were observed in balance, mobility, and upper and lower extremity muscle strength in the Pilates group (p < 0.05). No significant differences in any outcome measures were observed in the control group (p > 0.05). Due to its structure which is made up of balance and strengthening exercises, Pilates training may develop balance, mobility and muscle strength of MS patients. For this reason, we think that, Pilates exercises which are appropriate for the disability level of the patient may be suggested.

Melatonin: a "Higgs boson" in human reproduction.

PubMed

Dragojevic Dikic, Svetlana; Jovanovic, Ana Mitrovic; Dikic, Srdjan; Jovanovic, Tomislav; Jurisic, Aleksandar; Dobrosavljevic, Aleksandar

2015-02-01

As the Higgs boson could be a key to unlocking mysteries regarding our Universe, melatonin, a somewhat mysterious substance secreted by the pineal gland primarily at night, might be a crucial factor in regulating numerous processes in human reproduction. Melatonin is a powerful antioxidant which has an essential role in controlling several physiological reactions, as well as biological rhythms throughout human reproductive life. Melatonin, which is referred to as a hormone, but also as an autocoid, a chronobiotic, a hypnotic, an immunomodulator and a biological modifier, plays a crucial part in establishing homeostatic, neurohumoral balance and circadian rhythm in the body through synergic actions with other hormones and neuropeptides. This paper aims to analyze the effects of melatonin on the reproductive function, as well as to shed light on immunological and oncostatic properties of one of the most powerful hormones.

Quadcopter control in three-dimensional space using a noninvasive motor imagery-based brain-computer interface

NASA Astrophysics Data System (ADS)

LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

2013-08-01

Objective. At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional (3D) physical space using noninvasive scalp electroencephalogram (EEG) in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that the operation of a real world device has on subjects' control in comparison to a 2D virtual cursor task. Approach. Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a 3D physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Main results. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m s-1. Significance. Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user's ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in 3D physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG-based BCI systems for accomplish complex control in 3D physical space. The present study may serve as a framework for the investigation of multidimensional noninvasive BCI control in a physical environment using telepresence robotics.

Quadcopter control in three-dimensional space using a noninvasive motor imagery-based brain-computer interface.

PubMed

LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

2013-08-01

At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional (3D) physical space using noninvasive scalp electroencephalogram (EEG) in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that the operation of a real world device has on subjects' control in comparison to a 2D virtual cursor task. Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a 3D physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m s(-1). Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user's ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in 3D physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG-based BCI systems for accomplish complex control in 3D physical space. The present study may serve as a framework for the investigation of multidimensional noninvasive BCI control in a physical environment using telepresence robotics.

Quadcopter control in three-dimensional space using a noninvasive motor imagery based brain-computer interface

PubMed Central

LaFleur, Karl; Cassady, Kaitlin; Doud, Alexander; Shades, Kaleb; Rogin, Eitan; He, Bin

2013-01-01

Objective At the balanced intersection of human and machine adaptation is found the optimally functioning brain-computer interface (BCI). In this study, we report a novel experiment of BCI controlling a robotic quadcopter in three-dimensional physical space using noninvasive scalp EEG in human subjects. We then quantify the performance of this system using metrics suitable for asynchronous BCI. Lastly, we examine the impact that operation of a real world device has on subjects’ control with comparison to a two-dimensional virtual cursor task. Approach Five human subjects were trained to modulate their sensorimotor rhythms to control an AR Drone navigating a three-dimensional physical space. Visual feedback was provided via a forward facing camera on the hull of the drone. Individual subjects were able to accurately acquire up to 90.5% of all valid targets presented while travelling at an average straight-line speed of 0.69 m/s. Significance Freely exploring and interacting with the world around us is a crucial element of autonomy that is lost in the context of neurodegenerative disease. Brain-computer interfaces are systems that aim to restore or enhance a user’s ability to interact with the environment via a computer and through the use of only thought. We demonstrate for the first time the ability to control a flying robot in the three-dimensional physical space using noninvasive scalp recorded EEG in humans. Our work indicates the potential of noninvasive EEG based BCI systems to accomplish complex control in three-dimensional physical space. The present study may serve as a framework for the investigation of multidimensional non-invasive brain-computer interface control in a physical environment using telepresence robotics. PMID:23735712

The impact of time of day on the gait and balance control of Alzheimer's patients.

PubMed

Paillard, Thierry; Noé, Frederic; Bru, Noëlle; Couderc, Martine; Debove, Lola

2016-01-01

Alzheimer's patients suffer from circadian dysregulation. The aim of this study was to examine the evolution of balance control and gait at different times of the day (11:00, 14:00, 18:00) in order to identify whether Alzheimer's patients were more likely to fall at certain periods of the day. Spatio-temporal parameters of centre of foot pressure displacements were measured with a force platform and spatio-temporal parameters of walking were evaluated with a gait analysis device. The results highlighted that balance control was worse in the evening and the afternoon than in the morning. Furthermore, the walking speed was faster and support duration, swing duration and cycle duration were shorter in the evening than in the morning and afternoon. The combined analysis of balance control and gait parameters revealed that balance control and walking are concomitantly altered in the evening which increases the fall risk in the evening, in comparison with the morning, for Alzheimer's patients.

Fatigue does not conjointly alter postural and cognitive performance when standing in a shooting position under dual-task conditions.

PubMed

Bermejo, José Luis; García-Massó, Xavier; Paillard, Thierry; Noé, Frédéric

2018-02-01

This study investigated the effects of fatigue on balance control and cognitive performance in a standing shooting position. Nineteen soldiers were asked to stand while holding a rifle (single task - ST). They also had to perform this postural task while simultaneously completing a cognitive task (dual task - DT). Both the ST and DT were performed in pre- and post-fatigue conditions. In pre-fatigue, participants achieved better balance control in the DT than in the ST, thus suggesting that the increased cognitive activity associated with the DT improves balance control by shifting the attentional focus away from a highly automatised activity. In post-fatigue, balance control was degraded in both the ST and DT, while reaction time was enhanced in the first minutes following the fatiguing exercise without affecting the accuracy of response in the cognitive task, which highlights the relative independent effects of fatigue on balance control and cognitive performance.

Gait and balance of transfemoral amputees using passive mechanical and microprocessor-controlled prosthetic knees.

PubMed

Kaufman, K R; Levine, J A; Brey, R H; Iverson, B K; McCrady, S K; Padgett, D J; Joyner, M J

2007-10-01

Microprocessor-controlled knee joints appeared on the market a decade ago. These joints are more sophisticated and more expensive than mechanical ones. The literature is contradictory regarding changes in gait and balance when using these sophisticated devices. This study employed a crossover design to assess the comparative performance of a passive mechanical knee prosthesis compared to a microprocessor-controlled knee joint in 15 subjects with an above-knee amputation. Objective measurements of gait and balance were obtained. Subjects demonstrated significantly improved gait characteristics after receiving the microprocessor-controlled prosthetic knee joint (p<0.01). Improvements in gait were a transition from a hyperextended knee to a flexed knee during loading response which resulted in a change from an internal knee flexor moment to a knee extensor moment. The participants' balance also improved (p<0.01). All conditions of the Sensory Organization Test (SOT) demonstrated improvements in equilibrium score. The composite score also increased. Transfemoral amputees using a microprocessor-controlled knee have significant improvements in gait and balance.

How strongly does appetite counter weight loss? Quantification of the feedback control of human energy intake

PubMed Central

Polidori, David; Sanghvi, Arjun; Seeley, Randy; Hall, Kevin D.

2016-01-01

Objective To quantify the feedback control of energy intake in response to long-term covert manipulation of energy balance in free-living humans. Methods We used a validated mathematical method to calculate energy intake changes during a 52 week placebo-controlled trial in 153 patients treated with canagliflozin, a sodium glucose co-transporter inhibitor that increases urinary glucose excretion thereby resulting in weight loss without patients being directly aware of the energy deficit. We analyzed the relationship between the body weight time course and the calculated energy intake changes using principles from engineering control theory. Results We discovered that weight loss leads to a proportional increase in appetite resulting in eating above baseline by ~100 kcal/day per kg of lost weight – an amount more than 3-fold larger than the corresponding energy expenditure adaptations. Conclusions While energy expenditure adaptations are often thought to be the main reason for slowing of weight loss and subsequent regain, feedback control of energy intake plays an even larger role and helps explain why long-term maintenance of a reduced body weight is so difficult. PMID:27804272

Effect of Aerobic Loading on Static Balance in Young Athletes

ERIC Educational Resources Information Center

Akyüz, Öznur

2017-01-01

The fact that balances can also be a factor in performance distinction between athletes in athletic skills, and is considered to provide positive acceleration for physical development in which motor skills are exhibited. Human's skill to ensure balance can be defined as a determinant factor in development of other motor skills. From this point of…

Balancing Act: Bridging the Traditional and Technological Aspects of Culture through Art Education

ERIC Educational Resources Information Center

Lawton, Pamela Harris

2007-01-01

This paper addresses the benefits of connecting and balancing education in the visual arts and in technology through discussion of actual examples. This balanced connection accomplishes three goals: to further advance and enhance quality of life, to cultivate humane and ethical behaviors, and to initiate global dialogue on issues that matter among…

The Challenge of Maintaining a Healthy Microbiome During Long-Duration Space Missions.

NASA Astrophysics Data System (ADS)

Voorhies, Alexander; Lorenzi, Hernan

2016-07-01

Astronauts will face a host of challenges on long-duration space missions like a human expedition to Mars, including the difficulty of maintaining a balanced and healthy microbiome. The human microbiome is the collection of all microorganisms residing in and on a human host, and it plays an essential role in keeping humans healthy. However, imbalances in the microbiome have also been linked to many human diseases. Space travel has been shown to alter the microbiome of astronauts in ways that are not yet completely understood. Here we review past and current microbiology and microbiome research with the aim of determining the extent of change to the human microbiome caused by space travel and implications for astronaut health. We also address several challenges that will need to be overcome in order to facilitate long-duration human exploration missions. These challenges include maintaining environmental conditions that favor healthy microbiomes, controlling the microbial organisms astronauts are exposed to, the impact of galactic cosmic radiation on the microbiome, and medical interventions that can potentially damage the microbiome.

Validity and reliability of wii fit balance board for the assessment of balance of healthy young adults and the elderly.

PubMed

Chang, Wen-Dien; Chang, Wan-Yi; Lee, Chia-Lun; Feng, Chi-Yen

2013-10-01

[Purpose] Balance is an integral part of human ability. The smart balance master system (SBM) is a balance test instrument with good reliability and validity, but it is expensive. Therefore, we modified a Wii Fit balance board, which is a convenient balance assessment tool, and analyzed its reliability and validity. [Subjects and Methods] We recruited 20 healthy young adults and 20 elderly people, and administered 3 balance tests. The correlation coefficient and intraclass correlation of both instruments were analyzed. [Results] There were no statistically significant differences in the 3 tests between the Wii Fit balance board and the SBM. The Wii Fit balance board had a good intraclass correlation (0.86-0.99) for the elderly people and positive correlations (r = 0.58-0.86) with the SBM. [Conclusions] The Wii Fit balance board is a balance assessment tool with good reliability and high validity for elderly people, and we recommend it as an alternative tool for assessing balance ability.

Research on virtual network load balancing based on OpenFlow

NASA Astrophysics Data System (ADS)

Peng, Rong; Ding, Lei

2017-08-01

The Network based on OpenFlow technology separate the control module and data forwarding module. Global deployment of load balancing strategy through network view of control plane is fast and of high efficiency. This paper proposes a Weighted Round-Robin Scheduling algorithm for virtual network and a load balancing plan for server load based on OpenFlow. Load of service nodes and load balancing tasks distribution algorithm will be taken into account.

Interstitial ion homeostasis and acid-base balance are maintained in oedematous brain of mice with acute toxic liver failure.

PubMed

Obara-Michlewska, Marta; Ding, Fengfei; Popek, Mariusz; Verkhratsky, Alexei; Nedergaard, Maiken; Zielinska, Magdalena; Albrecht, Jan

2018-05-14

Acute toxic liver failure (ATLF) rapidly leads to brain oedema and neurological decline. We evaluated the ability of ATLF-affected brain to control the ionic composition and acid-base balance of the interstitial fluid. ATLF was induced in 10-12 weeks old male C57Bl mice by single intraperitoneal (i.p.) injection of 100 μg/g azoxymethane (AOM). Analyses were carried out in cerebral cortex of precomatous mice 20-24 h after AOM administration. Brain fluid status was evaluated by measuring apparent diffusion coefficient [ADC] using NMR spectroscopy, Evans Blue extravasation, and accumulation of an intracisternally-injected fluorescent tracer. Extracellular pH ([pH] e ) and ([K + ] e ) were measured in situ with ion-sensitive microelectrodes. Cerebral cortical microdialysates were subjected to photometric analysis of extracellular potassium ([K + ] e ), sodium ([Na + ] e ) and luminometric assay of extracellular lactate ([Lac] e ). Potassium transport in cerebral cortical slices was measured ex vivo as 86 Rb uptake. Cerebral cortex of AOM-treated mice presented decreased ADC supporting the view that ATLF-induced brain oedema is primarily cytotoxic in nature. In addition, increased Evans blue extravasation indicated blood brain barrier leakage, and increased fluorescent tracer accumulation suggested impaired interstitial fluid passage. However, [K + ] e , [Na + ] e , [Lac] e , [pH] e and potassium transport in brain of AOM-treated mice was not different from control mice. We conclude that in spite of cytotoxic oedema and deregulated interstitial fluid passage, brain of mice with ATLF retains the ability to maintain interstitial ion homeostasis and acid-base balance. Tentatively, uncompromised brain ion homeostasis and acid-base balance may contribute to the relatively frequent brain function recovery and spontaneous survival rate in human patients with ATLF. Copyright © 2018. Published by Elsevier Ltd.

History of cannabis use is associated with altered gait.

PubMed

Pearson-Dennett, Verity; Todd, Gabrielle; Wilcox, Robert A; Vogel, Adam P; White, Jason M; Thewlis, Dominic

2017-09-01

Despite evidence that cannabinoid receptors are located in movement-related brain regions (e.g., basal ganglia, cerebral cortex, and cerebellum), and that chronic cannabis use is associated with structural and functional brain changes, little is known about the long-term effect of cannabis use on human movement. The aim of the current study was to investigate balance and walking gait in adults with a history of cannabis use. We hypothesised that cannabis use is associated with subtle changes in gait and balance that are insufficient in magnitude for detection in a clinical setting. Cannabis users (n=22, 24±6years) and non-drug using controls (n=22, 25±8years) completed screening tests, a gait and balance test (with a motion capture system and in-built force platforms), and a clinical neurological examination of movement. Compared to controls, cannabis users exhibited significantly greater peak angular velocity of the knee (396±30 versus 426±50°/second, P=0.039), greater peak elbow flexion (53±12 versus 57±7°, P=0.038) and elbow range of motion (33±13 versus 36±10°, P=0.044), and reduced shoulder flexion (41±19 versus 26±16°, P=0.007) during walking gait. However, balance and neurological parameters did not significantly differ between the groups. The results suggest that history of cannabis use is associated with long-lasting changes in open-chain elements of walking gait, but the magnitude of change is not clinically detectable. Further research is required to investigate if the subtle gait changes observed in this population become more apparent with aging and increased cannabis use. Copyright © 2017 Elsevier B.V. All rights reserved.

Adaptation of multijoint coordination during standing balance in healthy young and healthy old individuals

PubMed Central

Pasma, J. H.; Schouten, A. C.; Aarts, R. G. K. M.; Meskers, C. G. M.; Maier, A. B.; van der Kooij, H.

2015-01-01

Standing balance requires multijoint coordination between the ankles and hips. We investigated how humans adapt their multijoint coordination to adjust to various conditions and whether the adaptation differed between healthy young participants and healthy elderly. Balance was disturbed by push/pull rods, applying two continuous and independent force disturbances at the level of the hip and between the shoulder blades. In addition, external force fields were applied, represented by an external stiffness at the hip, either stabilizing or destabilizing the participants' balance. Multivariate closed-loop system-identification techniques were used to describe the neuromuscular control mechanisms by quantifying the corrective joint torques as a response to body sway, represented by frequency response functions (FRFs). Model fits on the FRFs resulted in an estimation of time delays, intrinsic stiffness, reflexive stiffness, and reflexive damping of both the ankle and hip joint. The elderly generated similar corrective joint torques but had reduced body sway compared with the young participants, corresponding to the increased FRF magnitude with age. When a stabilizing or destabilizing external force field was applied at the hip, both young and elderly participants adapted their multijoint coordination by lowering or respectively increasing their neuromuscular control actions around the ankles, expressed in a change of FRF magnitude. However, the elderly adapted less compared with the young participants. Model fits on the FRFs showed that elderly had higher intrinsic and reflexive stiffness of the ankle, together with higher time delays of the hip. Furthermore, the elderly adapted their reflexive stiffness around the ankle joint less compared with young participants. These results imply that elderly were stiffer and were less able to adapt to external force fields. PMID:26719084

Biological effects of α-radiation exposure by (241)Am in Arabidopsis thaliana seedlings are determined both by dose rate and (241)Am distribution.

PubMed

Biermans, Geert; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Saenen, Eline; Van Hees, May; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

2015-11-01

Human activity has led to an increasing amount of radionuclides in the environment and subsequently to an increased risk of exposure of the biosphere to ionising radiation. Due to their high linear energy transfer, α-emitters form a threat to biota when absorbed or integrated in living tissue. Among these, (241)Am is of major concern due to high affinity for organic matter and high specific activity. This study examines the dose-dependent biological effects of α-radiation delivered by (241)Am at the morphological, physiological and molecular level in 14-day old seedlings of Arabidopsis thaliana after hydroponic exposure for 4 or 7 days. Our results show that (241)Am has high transfer to the roots but low translocation to the shoots. In the roots, we observed a transcriptional response of reactive oxygen species scavenging and DNA repair pathways. At the physiological and morphological level this resulted in a response which evolved from redox balance control and stable biomass at low dose rates to growth reduction, reduced transfer and redox balance decline at higher dose rates. This situation was also reflected in the shoots where, despite the absence of a transcriptional response, the control of photosynthesis performance and redox balance declined with increasing dose rate. The data further suggest that the effects in both organs were initiated in the roots, where the highest dose rates occurred, ultimately affecting photosynthesis performance and carbon assimilation. Though further detailed study of nutrient balance and (241)Am localisation is necessary, it is clear that radionuclide uptake and distribution is a major parameter in the global exposure effects on plant performance and health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Virtual Sensorimotor Training for Balance: Pilot Study Results for Children With Fetal Alcohol Spectrum Disorders.

PubMed

Jirikowic, Tracy; Westcott McCoy, Sarah; Price, Robert; Ciol, Marcia A; Hsu, Lin-Ya; Kartin, Deborah

2016-01-01

To examine the effects of Sensorimotor Training to Affect Balance, Engagement, and Learning (STABEL), a virtual reality system to train sensory adaptation for balance control, for children with fetal alcohol spectrum disorders (FASDs). Twenty-three children with FASDs received STABEL training in a university laboratory, or home, or were controls. The Movement Assessment Battery for Children-2nd edition (MABC-2) and Pediatric Clinical Test of Sensory Interaction for Balance-2 (P-CTSIB-2) were analyzed by group (lab, home, and control), session (pre-STABEL, 1 week post-STABEL, and 1 month post-STABEL), and group-by-session interaction. Significant effects were group and session for MABC-2 Balance and interaction for MABC-2 Total Motor and P-CTSIB-2. Preliminary results support improved sensory adaptation, balance, and motor performance post-STABEL, which warrant further study with a larger, randomized sample.

Selective weighting of cutaneous receptor feedback and associated balance impairments following short duration space flight.

PubMed

Strzalkowski, Nicholas D J; Lowrey, Catherine R; Perry, Stephen D; Williams, David R; Wood, Scott J; Bent, Leah R

2015-04-10

The present study investigated the perception of low frequency (3 Hz) vibration on the foot sole and its relationship to standing balance following short duration space flight in nine astronauts. Both 3 Hz vibration perception threshold (VPT) and standing balance measures increased on landing day compared to pre-flight. Contrary to our hypothesis, a positive linear relationship between these measures was not observed; however astronauts with the most sensitive skin (lowest 3 Hz VPT) were found to have the largest sway on landing day. While the change in foot sole sensitivity does not appear to directly relate to standing balance control, an exploratory strategy may be employed by astronauts whose threshold to pressure information is lower. Understanding sensory adaptations and balance control has implications to improve balance control strategies following space flight and in sensory impaired populations on earth. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Catchment Water-Energy Balance Model: Development and Applications

NASA Astrophysics Data System (ADS)

Yang, D.; Yang, H.

2017-12-01

International Hydrological community has widely recognized that the catchment water-energy balance exists, which can be expressed as a general form of E/P = f(E0/P, c), where P is precipitation, E0 is potential evaporation, and c is a parameter. Many empirical/rational formulations of the catchment water-energy balance have been proposed. Several analytical solutions of the water-energy balance equation E/P = f(E0/P, c) have been derived by using dimensional analysis and mathematic reasoning and introducing additional boundary conditions. This paper will summarize the catchment water-energy balance equations and discuss their advantages and limitations. Catchment hydrology has been greatly influenced by the intensive variability in land use/cover, precipitation and air temperature due to climate change and local human activities. The water-energy balance equation, which are usually called the Budyko framework is widely used to analyze the impacts of climate and landscape changes on regional hydrology especially the annual runoff change. In order to quantify impacts of climate change and landscape change on the catchment runoff, the climate elasticity and landscape elasticity are estimated theoretically from the catchment water-energy balance equation. The elasticity of runoff has less of a dependency on the aridity index when the climate is drier (larger aridity index). The precipitation elasticity of runoff was close to 1.0 and that of potential evaporation close to 0.0 in the extreme humid climate with no relation to the landscape conditions, which implies that catchment water balance under extremely wet condition is controlled mainly by the climate condition. We establishes a relationship between the change in the landscape parameter in the catchment water-energy balance equation and vegetation change represented by fPAR, the fraction of Photosynthetically Active Radiation absorbed by vegetation. The fPAR elasticity of runoff is introduced and estimated over China, which indicate that runoff is more sensitive to the change in fPAR in relatively dry catchments. This paper will summarize applications of the water-energy balance equation and discuss on the future development.

Body balance control deficiencies following ACL reconstruction combined with medial meniscus suture. A preliminary report.

PubMed

Parus, K; Lisiński, P; Huber, J

2015-11-01

Proprioception makes a critical contribution to body balance. The objective of this study was to evaluate static postural control after anterior cruciate ligament (ACL) reconstruction combined with medial meniscus (MM) suture, comparatively to healthy controls. Body balance is adversely affected 2 months after ACL reconstruction combined with MM suture. Fifteen patients (12 males and 3 females) aged 20 to 35 years (mean, 26.4 ± 6.0 years) who underwent ACL reconstruction with MM suture were compared to 20 healthy, physically active controls (16 females and 4 males) aged 19 to 23 years (mean, 21.1 ± 1.8 years), most of whom were physiotherapy students. Mean age was not significantly different between the patients and controls. A balance platform was used to estimate static postural control parameters. Each participant performed four tests, two in normal bipedal stance and two in tandem stance; in each stance, one test was done with the eyes open and the other with the eyes closed. We analysed global scores on a standardised 100-point scale and mean centre of pressure (COP) displacement velocity in the sagittal and frontal planes. Body balance was impaired 2 months after ACL reconstruction with MM suture. Thus, the patients had lower global scores and higher mean COP velocities in both the coronal and sagittal planes. Proprioception is impaired after ACL reconstruction with MM suture. Lack of visual control significantly decreases the ability to maintain balance. A balance platform is a useful diagnostic tool for patients with ACL reconstruction and MM suture. Level II. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Comprehensive, blinded assessment of balance in orthostatic tremor.

PubMed

Bhatti, Danish; Thompson, Rebecca; Xia, Yiwen; Hellman, Amy; Schmaderer, Lorene; Suing, Katie; McKune, Jennifer; Penke, Cynthia; Iske, Regan; Roeder, Bobbi Jo; Siu, Ka-Chun; Bertoni, John M; Torres-Russotto, Diego

2018-02-01

Orthostatic Tremor (OT) is a movement disorder characterized by a sensation of unsteadiness and tremors in the 13-18 Hz range present upon standing. The pathophysiology of OT is not well understood but there is a relationship between the sensation of instability and leg tremors. Despite the sensation of unsteadiness, OT patients do not fall often and balance in OT has not been formally assessed. We present a prospective blinded study comparing balance assessment in patients with OT versus healthy controls. We prospectively enrolled 34 surface Electromyography (EMG)-confirmed primary OT subjects and 21 healthy controls. Participants underwent evaluations of balance by blinded physical therapists (PT) with standardized, validated, commonly used balance scales and tasks. OT subjects were mostly female (30/34, 88%) and controls were majority males (13/20, 65%). The average age of OT subjects was 68.5 years (range 54-87) and for controls was 69.4 (range 32-86). The average duration of OT symptoms was 18 years. OT subjects did significantly worse on all the balance scales and on most balance tasks including Berg Balance Scale, Functional Gait Assessment, Dynamic Gait Index, Unipedal Stance Test, Functional Reach Test and pull test. Gait speed and five times sit to stand were normal in OT. Common validated balance scales are significantly abnormal in primary OT. Despite the objective finding of impaired balance, OT patients do not commonly have falls. The reported sensation of unsteadiness in this patient population seems to be out of proportion to the number of actual falls. Further studies are needed to determine which components of commonly used balance scales are affected by a sensation of unsteadiness and fear of falling. Copyright © 2017 Elsevier Ltd. All rights reserved.

The imbalanced surfing-life of humanity to survival in the global changes

NASA Astrophysics Data System (ADS)

Kontar, V. A.

2013-12-01

We have written many times about the imbalance of Nature as the cause of the global change. Here, we offer some method for the humanity survival in the face of global change of the imbalanced anisotropic real Nature. There are two logics of understanding the real Nature: the traditional balanced, and the new imbalanced. The balanced logic presupposes that Nature is balanced, isotropic, etc. The imbalanced logic presupposes opposite that Nature is imbalanced, anisotropic, etc. Respectively can be two styles of the people life: balanced and imbalanced. The image of the flat earth corresponds well with the balanced lifestyle of people. On the balanced life people spend activities to achieve the balance by reducing the change, stabilization, leveling any level changes, etc. If there is a mountain on the road, it must be align the track or make the tunnel. If there is a ravine on the road, then it need backfilled or to build a bridge. If someone is in restless, it must be calm, etc. As example of the happiness in the balanced life is the stability, balance, and therefore the global changes of Nature are perceived as a catastrophe. In the balanced lifestyle people can easily decide to use force, especially if there is not enough knowledge. But Nature has power which in billions times greater than the forces of humanity. Therefore, humanity will beaten in struggle with Nature and disappear. The imbalanced lifestyle is the fundamentally different. The imbalanced lifestyle complies with the surface of the ocean, which always changes, but sometimes can be and flat. But the flat calm ocean surface is inconvenient for the imbalanced life. You need to pull boat yourself because is no wind in the sails. The anisotropic imbalanced Nature has gradients in all parameters. At a certain level of knowledge and experience, people can use this multi-dimensional gradient essence of the real Nature for human's discretion. The imbalanced life is like a surfing. If properly understood Nature, you can find a route slip through the waves of Nature, which will bring closer the person to the desired goals. Of course, the changeable ocean is much more complicated than a flat surface. The imbalanced logic also is much more complex than the simplified balanced logic. As the calm ocean is like the flat surface, so same the balanced logic solutions are sometimes looks like as the truth, but only in the calm weather. At the normal ocean weather the balanced solutions are incorrect and mislead people. The river can be as image of the imbalanced surfing life. The river starts as small stream and running through all the obstacles to ocean. The water of river is flowing at the bottom of the potential trench of the Earth gravity and the Coriolis acceleration. For the imbalanced surfing life is most important not a steamroller of force, but the knowledge and perseverance in the search for the best path to the desirable goals. The example of happiness in the surfing imbalanced life can be joy from successfully usage the suitable trends of the anisotropic imbalanced real Nature. At the imbalanced surfing life should be the main guide: Nature doesn't have the bad weather. The global changes it is not catastrophe, but the normal state of the real anisotropic imbalanced Nature. Just everybody has to choose the weather which will be good for their personal surfing.

Muscle activation timing and balance response in chronic lower back pain patients with associated radiculopathy.

PubMed

Frost, Lydia R; Brown, Stephen H M

2016-02-01

Patients with chronic low back pain and associated radiculopathy present with neuromuscular symptoms both in their lower back and down their leg; however, investigations of muscle activation have so far been isolated to the lower back. During balance perturbations, it is necessary that lower limb muscles activate with proper timing and sequencing along with the lower back musculature to efficiently regain balance control. Patients with chronic low back pain and radiculopathy and matched controls completed a series of balance perturbations (rapid bilateral arm raise, unanticipated and anticipated sudden loading, and rapid rise to toe). Muscle activation timing and sequencing as well as kinetic response to the perturbations were analyzed. Patients had significantly delayed lower limb muscle activation in rapid arm raise trials as compared to controls. In sudden loading trials, muscle activation timing was not delayed in patients; however, some differences in posterior chain muscle activation sequencing were present. Patients demonstrated less anterior-posterior movement in unanticipated sudden loading trials, and greater medial-lateral movement in rise to toe trials. Patients with low back pain and radiculopathy demonstrated some significant differences from control participants in terms of muscle activation timing, sequencing, and overall balance control. The presence of differences between patients and controls, specifically in the lower limb, indicates that radiculopathy may play a role in altering balance control in these patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

The “Balance of Nature”—Evolution of a Panchreston

PubMed Central

Simberloff, Daniel

2014-01-01

The earliest concept of a balance of nature in Western thought saw it as being provided by gods but requiring human aid or encouragement for its maintenance. With the rise of Greek natural philosophy, emphasis shifted to traits gods endowed species with at the outset, rather than human actions, as key to maintaining the balance. The dominance of a constantly intervening God in the Middle Ages lessened interest in the inherent features of nature that would contribute to balance, but the Reformation led to renewed focus on such features, particularly traits of species that would maintain all of them but permit none to dominate nature. Darwin conceived of nature in balance, and his emphasis on competition and frequent tales of felicitous species interactions supported the idea of a balance of nature. But Darwin radically changed its underlying basis, from God to natural selection. Wallace was perhaps the first to challenge the very notion of a balance of nature as an undefined entity whose accuracy could not be tested. His skepticism was taken up again in the 20th century, culminating in a widespread rejection of the idea of a balance of nature by academic ecologists, who focus rather on a dynamic, often chaotic nature buffeted by constant disturbances. The balance-of-nature metaphor, however, lives on in large segments of the public, representing a fragile aspect of nature and biodiversity that it is our duty to protect. PMID:25290954

Feasibility of Wii Fit training to improve clinical measures of balance in older adults

PubMed Central

Bieryla, Kathleen A; Dold, Neil M

2013-01-01

Background and purpose Numerous interventions have been proposed to improve balance in older adults with varying degrees of success. A novel approach may be to use an off-the-shelf video game system utilizing real-time force feedback to train older adults. The purpose of this study is to investigate the feasibility of using Nintendo’s Wii Fit for training to improve clinical measures of balance in older adults and to retain the improvements after a period of time. Methods Twelve healthy older adults (aged >70 years) were randomly divided into two groups. The experimental group completed training using Nintendo’s Wii Fit game three times a week for 3 weeks while the control group continued with normal activities. Four clinical measures of balance were assessed before training, 1 week after training, and 1 month after training: Berg Balance Scale (BBS), Fullerton Advanced Balance (FAB) scale, Functional Reach (FR), and Timed Up and Go (TUG). Friedman two-way analysis of variance by ranks was conducted on the control and experimental group to determine if training using the Wii Balance Board with Wii Fit had an influence on clinical measures of balance. Results Nine older adults completed the study (experimental group n = 4, control group n = 5). The experimental group significantly increased their BBS after training while the control group did not. There was no significant change for either group with FAB, FR, and TUG. Conclusion Balance training with Nintendo’s Wii Fit may be a novel way for older adults to improve balance as measured by the BBS. PMID:23836967

Right cerebral hemisphere specialization for quiet and perturbed body balance control: Evidence from unilateral stroke.

PubMed

Fernandes, Corina Aparecida; Coelho, Daniel Boari; Martinelli, Alessandra Rezende; Teixeira, Luis Augusto

2018-02-01

Our aim in this investigation was to assess the relative importance of each cerebral hemisphere in quiet and perturbed balance, based on uni-hemispheric lesions by stroke. We tested the hypothesis of right cerebral hemisphere specialization for balance control. Groups of damage either to the right (RHD, n=9) or the left (LHD, n=7) cerebral hemisphere were compared across tasks requiring quiet balance or body balance recovery following a mechanical perturbation, comparing them to age-matched nondisabled individuals (controls, n=24). They were evaluated in conditions of full and occluded vision. In Experiment 1, the groups were compared in the task of quiet standing on (A) rigid and (B) malleable surfaces, having as outcome measures center of pressure (CoP) amplitude and velocity sway. In Experiment 2, we evaluated the recovery of body balance following a perturbation inducing forward body oscillation, having as outcome measures CoP displacement, peak hip and ankle rotations and muscular activation of both legs. Results from Experiment 1 showed higher values of CoP sway velocity for RHD in comparison to LHD and controls in the anteroposterior (rigid surface) and mediolateral (malleable surface) directions, while LHD had lower balance stability than the controls only in the mediolateral direction when supported on the rigid surface. In Experiment 2 results showed that RHD led to increased values in comparison to LHD and controls for anteroposterior CoP displacement and velocity, time to CoP direction reversion, hip rotation, and magnitude of muscular activation in the paretic leg, while LHD was found to differ in comparison to controls in magnitude of muscular activation of the paretic leg and amplitude of mediolateral sway only. These results suggest that damage to the right as compared to the left cerebral hemisphere by stroke leads to poorer postural responses both in quiet and perturbed balance. That effect was not altered by manipulation of sensory information. Our findings suggest that the right cerebral hemisphere plays a more prominent role in efferent processes responsible for balance control. Copyright © 2017 Elsevier B.V. All rights reserved.

Hallux valgus surgery may produce early improvements in balance control: results of a cross-sectional pilot study.

PubMed

Sadra, Saba; Fleischer, Adam; Klein, Erin; Grewal, Gurtej S; Knight, Jessica; Weil, Lowell Scott; Weil, Lowell; Najafi, Bijan

2013-01-01

Hallux valgus (HV) is associated with poorer performance during gait and balance tasks and is an independent risk factor for falls in older adults. We sought to assess whether corrective HV surgery improves gait and balance. Using a cross-sectional study design, gait and static balance data were obtained from 40 adults: 19 patients with HV only (preoperative group), 10 patients who recently underwent successful HV surgery (postoperative group), and 11 control participants. Assessments were made in the clinic using body-worn sensors. Patients in the preoperative group generally demonstrated poorer static balance control compared with the other two groups. Despite similar age and body mass index, postoperative patients exhibited 29% and 63% less center of mass sway than preoperative patients during double-and single-support balance assessments, respectively (analysis of variance P =.17 and P =.14, respectively [both eyes open condition]). Overall, gait performance was similar among the groups, except for speed during gait initiation, where lower speeds were encountered in the postoperative group compared with the preoperative group (Scheffe P = .049). This study provides supportive evidence regarding the benefits of corrective lower-extremity surgery on certain aspects of balance control. Patients seem to demonstrate early improvements in static balance after corrective HV surgery, whereas gait improvements may require a longer recovery time. Further research using a longitudinal study design and a larger sample size capable of assessing the long-term effects of HV surgical correction on balance and gait is probably warranted.

Gait and Balance in Essential Tremor: Variable Effects of Bilateral Thalamic Stimulation

PubMed Central

Earhart, Gammon M.; Clark, B. Ruth; Tabbal, Samer D.; Perlmutter, Joel S.

2010-01-01

Essential tremor (ET) is a multi-faceted condition best known for postural and action tremor but also may include disordered gait and postural instability. Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) of the thalamus provides substantial tremor reduction yet some patients with bilateral VIM DBS have gait and balance impairment. This study examines gait and balance performance in 13 participants with ET who have bilateral VIM DBS compared to a matched control group. Participants with ET were tested with their stimulators off (DBS OFF) and on (DBS ON). For both standard and tandem walking, participants with ET walked significantly more slowly than controls, with significantly lower cadence, spending a lower percentage of the gait cycle in single limb support and a higher percentage in double support compared to controls. Participants with ET also had significantly lower tandem and one leg stance times, Berg balance scores, balance confidence, and required significantly greater time to perform the Timed Up-and-Go relative to controls. There were no significant differences in any gait or balance measures in the DBS OFF versus DBS ON conditions, but the effects of DBS on gait and balance were highly variable among individuals. Future studies are needed to determine why some individuals experience gait and balance difficulties after bilateral thalamic DBS and others do not. A better understanding of the mechanisms underlying gait and balance impairments in those with bilateral DBS is critical in order to reduce falls and fractures in this group. PMID:19006189

Eight Essential Foods in Iranian Traditional Medicine and their Role in Health Promotion and Well-being.

PubMed

Zeinalian, Mehrdad; Eshaghi, Mehdi; Hadian, Mahdi; Naji, Homayoun; Marandi, Sayed Mohammad Masoud; Asgary, Sedigheh

2017-01-01

Eight essential foods (EEF) described in Iranian traditional medicine (ITM) have a determinant role to balance human temperament insuring health and well-being. EEF included oral, imaginary, auditory, visual, olfactory, touch, sexual, and familiarity food. Oral foods should be halal, compatible with individual temper, consumed up twice a day, and compatible with different seasons and geographic conditions. Imaginary food consists of the individual thought content which is directly related to mental and physical fitness. It helps to balance temperament if be free of negative thoughts such as suspicion and distrust to others. Auditory food includes all sounds surrounding us, some of which are sedative and help to balance temperaments, such as natural sounds, and spiritual and beautiful words. Visual food includes everything in the range of human vision which is impressive on his/her thought. Natural beautiful scenes have almost a warm temper and help to balance human temperament. Olfactory food includes odors which stimulate the smell. Touch food includes all materials in direct contact with body skin, like clothes, which have a determinant role in temper moderation in the case of being natural. Sexual food complies with the human need to express his/her love and/or is loved, so its fulfillment could prevent human mal-temperament. Familiarity food can be provided by companion with friends and family members and has a significant role to insure well-being. Given the comprehensiveness of EEF in ITM which covers all human health-related aspects, we can insure health and well-being among our population by promoting and public educating of these principles.

Eight Essential Foods in Iranian Traditional Medicine and their Role in Health Promotion and Well-being

PubMed Central

Zeinalian, Mehrdad; Eshaghi, Mehdi; Hadian, Mahdi; Naji, Homayoun; Marandi, Sayed Mohammad Masoud; Asgary, Sedigheh

2017-01-01

Eight essential foods (EEF) described in Iranian traditional medicine (ITM) have a determinant role to balance human temperament insuring health and well-being. EEF included oral, imaginary, auditory, visual, olfactory, touch, sexual, and familiarity food. Oral foods should be halal, compatible with individual temper, consumed up twice a day, and compatible with different seasons and geographic conditions. Imaginary food consists of the individual thought content which is directly related to mental and physical fitness. It helps to balance temperament if be free of negative thoughts such as suspicion and distrust to others. Auditory food includes all sounds surrounding us, some of which are sedative and help to balance temperaments, such as natural sounds, and spiritual and beautiful words. Visual food includes everything in the range of human vision which is impressive on his/her thought. Natural beautiful scenes have almost a warm temper and help to balance human temperament. Olfactory food includes odors which stimulate the smell. Touch food includes all materials in direct contact with body skin, like clothes, which have a determinant role in temper moderation in the case of being natural. Sexual food complies with the human need to express his/her love and/or is loved, so its fulfillment could prevent human mal-temperament. Familiarity food can be provided by companion with friends and family members and has a significant role to insure well-being. Given the comprehensiveness of EEF in ITM which covers all human health-related aspects, we can insure health and well-being among our population by promoting and public educating of these principles. PMID:28217264

Long-term follow-up of a randomized controlled trial on additional core stability exercises training for improving dynamic sitting balance and trunk control in stroke patients.

PubMed

Cabanas-Valdés, Rosa; Bagur-Calafat, Caritat; Girabent-Farrés, Montserrat; Caballero-Gómez, Fernanda Mª; du Port de Pontcharra-Serra, Helena; German-Romero, Ana; Urrútia, Gerard

2017-11-01

Analyse the effect of core stability exercises in addition to conventional physiotherapy training three months after the intervention ended. A randomized controlled trial. Outpatient services. Seventy-nine stroke survivors. In the intervention period, both groups underwent conventional physiotherapy performed five days/week for five weeks, and in addition the experimental group performed core stability exercises for 15 minutes/day. Afterwards, during a three-month follow-up period, both groups underwent usual care that could eventually include conventional physiotherapy or physical exercise but not in a controlled condition. Primary outcome was trunk control and dynamic sitting balance assessed by the Spanish-Version of Trunk Impairment Scale 2.0 and Function in Sitting Test. Secondary outcomes were standing balance and gait evaluated by the Berg Balance Scale, Tinetti Test, Brunel Balance Assessment, Spanish-Version of Postural Assessment Scale for Stroke and activities of daily living using the Barthel Index. A total of 68 subjects out of 79 completed the three-month follow-up period. The mean difference (SD) between groups was 0.78 (1.51) points ( p = 0.003) for total score on the Spanish-Version of Trunk Impairment Scale 2.0, 2.52 (6.46) points ( p = 0.009) for Function in Sitting Test, dynamic standing balance was 3.30 (9.21) points ( p= 0.009) on the Berg Balance Scale, gait was 0.82 (1.88) points ( p = 0.002) by Brunel Balance Assessment (stepping), and 1.11 (2.94) points ( p = 0.044) by Tinetti Test (gait), all in favour of core stability exercises. Core stability exercises plus conventional physiotherapy have a positive long-term effect on improving dynamic sitting and standing balance and gait in post-stroke patients.

Balance circuit classes to improve balance among rehabilitation inpatients: a protocol for a randomised controlled trial

PubMed Central

2013-01-01

Background Impaired balance and mobility are common among rehabilitation inpatients. Poor balance and mobility lead to an increased risk of falling. Specific balance exercise has been shown to improve balance and reduce falls within the community setting. However few studies have measured the effects of balance exercises on balance within the inpatient setting. The aim of this randomised controlled trial is to investigate whether the addition of circuit classes targeting balance to usual therapy lead to greater improvements in balance among rehabilitation inpatients than usual therapy alone. Methods/Design A single centre, randomised controlled trial with concealed allocation, assessor blinding and intention-to-treat analysis. One hundred and sixty two patients admitted to the general rehabilitation ward at Bankstown-Lidcombe Hospital will be recruited. Eligible participants will have no medical contraindications to exercise and will be able to: fully weight bear; stand unaided independently for at least 30 seconds; and participate in group therapy sessions with minimal supervision. Participants will be randomly allocated to an intervention group or usual-care control group. Both groups will receive standard rehabilitation intervention that includes physiotherapy mobility training and exercise for at least two hours on each week day. The intervention group will also receive six 1-hour circuit classes of supervised balance exercises designed to maximise the ability to make postural adjustments in standing, stepping and walking. The primary outcome is balance. Balance will be assessed by measuring the total time the participant can stand unsupported in five different positions; feet apart, feet together, semi-tandem, tandem and single-leg-stance. Secondary outcomes include mobility, self reported physical functioning, falls and hospital readmissions. Performance on the outcome measures will be assessed before randomisation and at two-weeks and three-months after randomisation by physiotherapists unaware of intervention group allocation. Discussion This study will determine the impact of additional balance circuit classes on balance among rehabilitation inpatients. The results will provide essential information to guide evidence-based physiotherapy at the study site as well as across other rehabilitation inpatient settings. Trial registration The protocol for this study is registered with the Australian New Zealand, Clinical Trials Registry: ACTRN=12611000412932 PMID:23870654

Virtual-reality balance training with a video-game system improves dynamic balance in chronic stroke patients.

PubMed

Cho, Ki Hun; Lee, Kyoung Jin; Song, Chang Ho

2012-09-01

Stroke is one of the most serious healthcare problems and a major cause of impairment of cognition and physical functions. Virtual rehabilitation approaches to postural control have been used for enhancing functional recovery that may lead to a decrease in the risk of falling. In the present study, we investigated the effects of virtual reality balance training (VRBT) with a balance board game system on balance of chronic stroke patients. Participants were randomly assigned to 2 groups: VRBT group (11 subjects including 3 women, 65.26 years old) and control group (11 subjects including 5 women, 63.13 years old). Both groups participated in a standard rehabilitation program (physical and occupational therapy) for 60 min a day, 5 times a week for 6 weeks. In addition, the VRBT group participated in VRBT for 30 min a day, 3 times a week for 6 weeks. Static balance (postural sway velocity with eyes open or closed) was evaluated with the posturography. Dynamic balance was evaluated with the Berg Balance Scale (BBS) and Timed Up and Go test (TUG) that measures balance and mobility in dynamic balance. There was greater improvement on BBS (4.00 vs. 2.81 scores) and TUG (-1.33 vs. -0.52 sec) in the VRBT group compared with the control group (P < 0.05), but not on static balance in both groups. In conclusion, we demonstrate a significant improvement in dynamic balance in chronic stroke patients with VRBT. VRBT is feasible and suitable for chronic stroke patients with balance deficit in clinical settings.

The internal representation of head orientation differs for conscious perception and balance control

PubMed Central

Dalton, Brian H.; Rasman, Brandon G.; Inglis, J. Timothy

2017-01-01

Key points We tested perceived head‐on‐feet orientation and the direction of vestibular‐evoked balance responses in passively and actively held head‐turned postures.The direction of vestibular‐evoked balance responses was not aligned with perceived head‐on‐feet orientation while maintaining prolonged passively held head‐turned postures. Furthermore, static visual cues of head‐on‐feet orientation did not update the estimate of head posture for the balance controller.A prolonged actively held head‐turned posture did not elicit a rotation in the direction of the vestibular‐evoked balance response despite a significant rotation in perceived angular head posture.It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Abstract Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head‐on‐feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head‐turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole‐body balance responses. Visual recalibration of head‐on‐feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular‐evoked balance response was not orthogonal to perceived head‐on‐feet orientation, regardless of the visual information provided. For prolonged head‐turned postures, balance responses consistent with actual head‐on‐feet posture occurred only during the active condition. Our results indicate that conscious perception of head‐on‐feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head‐on‐feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head‐on‐feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. PMID:28035656

Detecting dynamical boundaries from kinematic data in biomechanics

NASA Astrophysics Data System (ADS)

Ross, Shane D.; Tanaka, Martin L.; Senatore, Carmine

2010-03-01

Ridges in the state space distribution of finite-time Lyapunov exponents can be used to locate dynamical boundaries. We describe a method for obtaining dynamical boundaries using only trajectories reconstructed from time series, expanding on the current approach which requires a vector field in the phase space. We analyze problems in musculoskeletal biomechanics, considered as exemplars of a class of experimental systems that contain separatrix features. Particular focus is given to postural control and balance, considering both models and experimental data. Our success in determining the boundary between recovery and failure in human balance activities suggests this approach will provide new robust stability measures, as well as measures of fall risk, that currently are not available and may have benefits for the analysis and prevention of low back pain and falls leading to injury, both of which affect a significant portion of the population.

Self-renewal of a purified Tie2+ hematopoietic stem cell population relies on mitochondrial clearance.

PubMed

Ito, Kyoko; Turcotte, Raphaël; Cui, Jinhua; Zimmerman, Samuel E; Pinho, Sandra; Mizoguchi, Toshihide; Arai, Fumio; Runnels, Judith M; Alt, Clemens; Teruya-Feldstein, Julie; Mar, Jessica C; Singh, Rajat; Suda, Toshio; Lin, Charles P; Frenette, Paul S; Ito, Keisuke

2016-12-02

A single hematopoietic stem cell (HSC) is capable of reconstituting hematopoiesis and maintaining homeostasis by balancing self-renewal and cell differentiation. The mechanisms of HSC division balance, however, are not yet defined. Here we demonstrate, by characterizing at the single-cell level a purified and minimally heterogeneous murine Tie2 + HSC population, that these top hierarchical HSCs preferentially undergo symmetric divisions. The induction of mitophagy, a quality control process in mitochondria, plays an essential role in self-renewing expansion of Tie2 + HSCs. Activation of the PPAR (peroxisome proliferator-activated receptor)-fatty acid oxidation pathway promotes expansion of Tie2 + HSCs through enhanced Parkin recruitment in mitochondria. These metabolic pathways are conserved in human TIE2 + HSCs. Our data thus identify mitophagy as a key mechanism of HSC expansion and suggest potential methods of cell-fate manipulation through metabolic pathways. Copyright © 2016, American Association for the Advancement of Science.

Self-renewal of a purified Tie2+ hematopoietic stem cell population relies on mitochondrial clearance

PubMed Central

Ito, Kyoko; Turcotte, Raphaël; Cui, Jinhua; Zimmerman, Samuel E.; Pinho, Sandra; Mizoguchi, Toshihide; Arai, Fumio; Runnels, Judith M.; Alt, Clemens; Teruya-Feldstein, Julie; Mar, Jessica C.; Singh, Rajat; Suda, Toshio; Lin, Charles P.; Frenette, Paul S.; Ito, Keisuke

2016-01-01

A single hematopoietic stem cell (HSC) is capable of reconstituting hematopoiesis and maintaining homeostasis by balancing self-renewal and cell differentiation. The mechanisms of HSC division balance, however, are not yet defined. Here we demonstrate, by characterizing at the single-cell level a purified and minimally heterogeneous murine Tie2+ HSC population, that these top hierarchical HSCs preferentially undergo symmetric divisions. The induction of mitophagy, a quality control process in mitochondria, plays an essential role in self-renewing expansion of Tie2+ HSCs. Activation of the PPAR (peroxisome proliferator–activated receptor)–fatty acid oxidation pathway promotes expansion of Tie2+ HSCs through enhanced Parkin recruitment in mitochondria. These metabolic pathways are conserved in human TIE2+ HSCs. Our data thus identify mitophagy as a key mechanism of HSC expansion and suggest potential methods of cell-fate manipulation through metabolic pathways. PMID:27738012

The roles of PIKE in tumorigenesis

PubMed Central

Qi, Qi; Ye, Keqiang

2013-01-01

Tumorigenesis is the process by which normal cells evolve the capacity to evade and overcome the constraints usually placed upon their growth and survival. To ensure the integrity of organs and tissues, the balance of cell proliferation and cell death is tightly maintained. The proteins controlling this balance are either considered oncogenes, which promote tumorigenesis, or tumor suppressors, which prevent tumorigenesis. Phosphoinositide 3-kinase enhancer (PIKE) is a family of GTP-binding proteins that possess anti-apoptotic functions and play an important role in the central nervous system. Notably, accumulating evidence suggests that PIKE is a proto-oncogene involved in tumor progression. The PIKE gene (CENTG1) is amplified in a variety of human cancers, leading to the resistance against apoptosis and the enhancement of invasion. In this review, we will summarize the functions of PIKE proteins in tumorigenesis and discuss their potential implications in cancer therapy. PMID:23770988

Bone Formation Rate in Experimental Disuse Osteoporosis in Monkeys

NASA Technical Reports Server (NTRS)

Cann, Christopher; Young, Donald R.

1976-01-01

Specific mechanisms underlying weightless and hypodynamic bone loss are obscure. A principal relationship which must be affected is the balance between bone formation and bone resorption rates. In order to better define the influence of those parameters on bone loss, and also to develop measurements in other species as a useful adjunct to human research, studies were undertaken with experimental monkeys. Tests were conducted with a total of 6 adult male monkeys, weighing 10-13 kg, and approximately 10-12 yrs. of age to evaluate specifically bone formation rate during the development of disuse osteoporosis and osteopenia. Three animals were restrained in a semi-recumbent position for six months; three animals served as normal caged controls. Food intake (Purina) was held relatively constant at 200g/day for each animal. Using a Norland Bone Mineral Analyzer, bone mineral losses of 3.5 to 6% were seen in the mid-shaft of the tibia and in the distal radius. Bone loss was confirmed radiographically, with observation of thinning of the proximal tibial cortex and trabeculae in the calcaneus. Bone formation rate was determined using standard Ca-47 kinetics under metabolic balance conditions. After six months of restraint, accretion was 7.2-13.2 mg Ca/kg/day, compared to 3.2-4.1 mg Ca/kg/day in caged controls and 3-8 mg Ca/kg/day in normal adult humans. Fecal and urine calcium was 25-40% higher in restrained animals than in controls. Dietary calcium absorption decreases during restraint, and calcium turnover increases, implying a rise in bone resorption rate concommitant with the observed rise in bone accretion rate. Further studies dealing specifically with bone resorption are underway to define this more fully.

Gait Balance Disorder by Thalamic Infarction with the Disorder of Interstitial Nucleus of Cajal

PubMed Central

Kurosu, A.; Hayashi, Y.; Wada, K.; Nagaoka, M.

2011-01-01

The interstitial nucleus of Cajal (INC) is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movement disorders and abnormal head tilt due to thalamic infarction. We performed ophthalmic examinations on and checked the balance of them. With funduscopy, abnormal cycloduction was seen in the unaffected side and normal cycloduction was observed in the affected side. Nevertheless, Hess charts showed distortions in the visual image of both eyes. They all had disorders of balance control. We tried to treat them using the Bobath approach for improving their ambulatory balance. With subsequent improvements in balance control it was possible for them to take short walks, but it was difficult to make any improvements in their ocular movement. The INC is related to balance control of ambulation and disorders of the INC induce ambulatory disturbances. Cycloduction was only observed in the unaffected side, but Hess charts showed distortions of the visual image in both eyes. Ambulation was briefly improved, but diplopia persisted in these patients. PMID:21769260

Development of closed loop roll control for magnetic balance systems

NASA Technical Reports Server (NTRS)

Covert, E. E.; Haldeman, C. W.; Ramohalli, G.; Way, P.

1982-01-01

This research was undertaken with the goal of demonstrating closed loop control of the roll degree of freedom on the NASA prototype magnetic suspension and balance system at the MIT Aerophysics Laboratory, thus, showing feasibility for a roll control system for any large magnetic balance system which might be built in the future. During the research under this grant, study was directed toward the several areas of torque generation, position sensing, model construction and control system design. These effects were then integrated to produce successful closed loop operation of the analogue roll control system. This experience indicated the desirability of microprocessor control for the angular degrees of freedom.

KineAssist: design and development of a robotic overground gait and balance therapy device.

PubMed

Patton, James; Brown, David A; Peshkin, Michael; Santos-Munné, Julio J; Makhlin, Alex; Lewis, Ela; Colgate, Edward J; Schwandt, Doug

2008-01-01

Balance and mobility training consists of activities that carry a high risk for falling. The purpose of this article is to describe a novel robotic system for allowing challenging, yet safe, balance and mobility training in persons at high risk for falls. With no initial preconceptions of what device we would build, a user-needs analysis led us to focus on increasing the level of challenge to a patient's ability to maintain balance during gait training and also on maintaining direct involvement of a physical therapist (rather than attempting robotic replacement). The KineAssist is a robotic device for gait and balance training that has emerged from a unique design process of a start-up product of a small company and a team of therapists, engineers, mechanical design experts, and rehabilitation scientists. The KineAssist provides partial body weight support and postural control on the torso; allows many axes of motion of the trunk and pelvis; leaves the patient's legs accessible to a physical therapist's manipulation during walking; follows a patient's walking motions overground in forward, rotation, and sidestepping directions; and catches an individual who loses balance and begins to fall. Design and development of the KineAssist proceeded more rapidly in the context of a small company than would have been possible in most institutional research contexts. A prototype KineAssist has been constructed and has received US Food and Drug Administration (FDA) classification and institutional review board clearance for initial human studies. The acceptance of KineAssist will ultimately depend on improved patient outcomes, the use of this new tool by therapists, the ease of use of the system, and the recognition of the unique value it brings to therapeutic recovery.

Positive feedback of greenhouse gas balances to warming is determined by non-growing season emissions in an alpine meadow

NASA Astrophysics Data System (ADS)

Niu, S.; Wang, J.; Quan, Q.; Chen, W.; Wen, X.; Yu, G.

2017-12-01

Large uncertainties exist in the sources and sinks of greenhouse gases (CO2, CH4, N2O) in response to climate warming and human activity. So far, numerous previous studies have evaluated the CO2 budget, but little attention has paid to CH4 and N2O budgets and the concurrent balance of these three gases in combination, especially in the non-growing season. Here, we synthesized eddy covariance measurement with the automatic chamber measurements of CO2, CH4, and N2O exposed to three levels of temperature treatments (ambient, +1.5 °C, +2.5 °C) and two disturbance treatments (ummowing, mowing) in an alpine meadow on the Tibetan Plateau. We have found that warming caused increase in CH4 uptake and decrease in N2O emission offset little of the enhancement in CO2 emission, triggering a positive feedback to climate warming. Warming switches the ecosystem from a net sink (-17 ± 14 g CO2-eq m-2 yr-1) in the control to a net source of greenhouse gases of 94 ± 36 gCO2-eq m-2 yr-1 in the plots with +1.5 °C warming treatment, and 177 ± 6 gCO2-eq m-2 yr-1 in the plots with +2.5 °C warming treatment. The changes in the non-growing season balance, rather than those in the growing season, dominate the warming responses of annual greehouse gas balance. And this is not changed by mowing. The dominant role of responses of winter greenhouse gas balance in the positive feedback of ecosystem to climate warming highlights that greenhouse gas balance in cold season has to be considered when assessing climate-carbon cycle feedback.

Optimal case-control matching in practice.

PubMed

Cologne, J B; Shibata, Y

1995-05-01

We illustrate modern matching techniques and discuss practical issues in defining the closeness of matching for retrospective case-control designs (in which the pool of subjects already exists when the study commences). We empirically compare matching on a balancing score, analogous to the propensity score for treated/control matching, with matching on a weighted distance measure. Although both methods in principle produce balance between cases and controls in the marginal distributions of the matching covariates, the weighted distance measure provides better balance in practice because the balancing score can be poorly estimated. We emphasize the use of optimal matching based on efficient network algorithms. An illustration is based on the design of a case-control study of hepatitis B virus infection as a possible confounder and/or effect modifier of radiation-related primary liver cancer in atomic bomb survivors.

Navigating a Maze with Balance Board and Wiimote

NASA Astrophysics Data System (ADS)

Fikkert, Wim; Hoeijmakers, Niek; van der Vet, Paul; Nijholt, Anton

Input from the lower body in human-computer interfaces can be beneficial, enjoyable and even entertaining when users are expected to perform tasks simultaneously. Users can navigate a virtual (game) world or even an (empirical) dataset while having their hands free to issue commands. We compared the Wii Balance Board to a hand-held Wiimote for navigating a maze and found that users completed this task slower with the Balance Board. However, the Balance Board was considered more intuitive, easy to learn and ‘much fun’.

Cardiac and renal function in patients with type 2 diabetes who have chronic kidney disease: potential effects of bardoxolone methyl.

PubMed

McCullough, Peter A; Ali, Sajid

2012-01-01

The intracellular and tissue balance of oxidant and antioxidant forces is a potential therapeutic target for a variety of agents in the treatment of complications due to chronic disease including diabetes mellitus and hypertension. There are a myriad of processes controlled at the level of genes, transcription factors, and protein messages that work to control the normal use of oxidative reactions within cells. Loss of control of these processes may lead to reversible dysfunction in many cell lines including the podocyte, renal tubular cells, and cardiac myocytes. Bardoxolone methyl is a novel nuclear regulator factor (Nrf-2) activator which works to tip the balance of effects towards antioxidation and as an observation made serendipitously, improves renal filtration function in humans after approximately 12 weeks of therapy. The improvement in estimated glomerular filtration can be up to 30% in those with stage 3 and 4 chronic kidney disease. However, experimental evidence suggests there may be a consequence of relative hyperfiltration in diseased kidneys as well as potential adverse effects on skeletal and cardiac myocytes. Only large, prospective randomized trials with carefully collected and adjudicated clinical outcomes will inform the research community on the therapeutic risks and benefits of this important new agent.

Cardiac and renal function in patients with type 2 diabetes who have chronic kidney disease: potential effects of bardoxolone methyl

PubMed Central

McCullough, Peter A; Ali, Sajid

2012-01-01

The intracellular and tissue balance of oxidant and antioxidant forces is a potential therapeutic target for a variety of agents in the treatment of complications due to chronic disease including diabetes mellitus and hypertension. There are a myriad of processes controlled at the level of genes, transcription factors, and protein messages that work to control the normal use of oxidative reactions within cells. Loss of control of these processes may lead to reversible dysfunction in many cell lines including the podocyte, renal tubular cells, and cardiac myocytes. Bardoxolone methyl is a novel nuclear regulator factor (Nrf-2) activator which works to tip the balance of effects towards antioxidation and as an observation made serendipitously, improves renal filtration function in humans after approximately 12 weeks of therapy. The improvement in estimated glomerular filtration can be up to 30% in those with stage 3 and 4 chronic kidney disease. However, experimental evidence suggests there may be a consequence of relative hyperfiltration in diseased kidneys as well as potential adverse effects on skeletal and cardiac myocytes. Only large, prospective randomized trials with carefully collected and adjudicated clinical outcomes will inform the research community on the therapeutic risks and benefits of this important new agent. PMID:22787387

Improvement of anticipatory postural adjustments for balance control: effect of a single training session.

PubMed

Kanekar, Neeta; Aruin, Alexander S

2015-04-01

Humans use anticipatory and compensatory postural strategies to maintain and restore balance when perturbed. Inefficient generation and utilization of anticipatory postural adjustments (APAs) is one of the reasons for postural instability. The aim of the study was to investigate the role of training in improvement of APAs and its effect on subsequent control of posture. Thirteen healthy young adults were exposed to predictable external perturbations before and after a single training session consisting of catches of a medicine ball thrown at the shoulder level. 3-D body kinematics, EMG activity of thirteen trunk and lower limb muscles, and ground reaction forces were recorded before and immediately after a single training session. Muscle onsets, EMG integrals, center of pressure (COP), and center of mass (COM) displacements were analyzed during the anticipatory and compensatory phases of postural control. The effect of a single training session was seen as significantly early muscle onsets and larger anticipatory COP displacements. As a result, significantly smaller peak COM displacements were observed after the perturbation indicating greater postural stability. The outcome of this study provides a background for examining the role of training in improvement of APAs and its effect on postural stability in individuals in need. Copyright © 2014 Elsevier Ltd. All rights reserved.

Compensatory mechanisms of balance to the scaling of arm-swing frequency.

PubMed

Ko, Ji Hyun; Wang, Zheng; Challis, John H; Newell, Karl M

2015-11-05

The present study investigated the contribution of the Hof (2007) mechanism 1 (M1-moving the center of pressure (COP) with respect to the vertical projection of the center of mass (COMTotal)); and mechanism 2 (M2-rotating the trunk and upper limbs around the COMTotal) to postural control and the stability of COP-COMTotal cophase as a function of lateral arm-swing frequency. Young adults were instructed to stand still on a force platform while alternating their arm swinging from above the head to the side of their thigh to create perturbations to postural control. Scaling the frequency of arm-swing (random step changes of 0.2 Hz within a bandwidth of 0.2 to 1.6 Hz) increased the SD of COP but decreased the SD of COMTotal. Increments in arm-swing frequency induced a progressive increase in M1 and decrease in M2 in terms of their relative contribution to postural stability. The cophase between COP and COMTotal became more tightly in-phase over increments of arm-swing frequency. These findings show an adaptive compensatory role of M1 and M2 within the stability of COP-COMTotal coupling in the regulation of human balance control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Seeking Balance in Motion: The Role of Spontaneous Free Play in Promoting Social and Emotional Health in Early Childhood Care and Education

PubMed Central

Hewes, Jane

2014-01-01

There is accumulating scientific evidence of the potential of play and playfulness to enhance human capacity to respond to adversity and cope with the stresses of everyday life. In play we build a repertoire of adaptive, flexible responses to unexpected events, in an environment separated from the real consequences of those events. Playfulness helps us maintain social and emotional equilibrium in times of rapid change and stress. Through play, we experience flow—A feeling of being taken to another place, out of time, where we have controlled of the world. This paper argues that spontaneous free play, controlled and directed by children and understood from the child’s perspective, contributes to children’s subjective experience of well-being, building a foundation for life-long social and emotional health. The paradoxical nature of young children’s spontaneous free play is explored. Adaptability, control, flexibility, resilience and balance result from the experience of uncertainty, unpredictability, novelty and non-productivity. These essential dimensions of young children’s spontaneous free play typically produce play which is experienced by adults as chaotic, nonsensical and disruptive. The article concludes with a preliminary discussion of the challenges and possibilities of providing for spontaneous free play indoors, in early childhood care and education programs. PMID:27417480

Seeking Balance in Motion: The Role of Spontaneous Free Play in Promoting Social and Emotional Health in Early Childhood Care and Education.

PubMed

Hewes, Jane

2014-10-01

There is accumulating scientific evidence of the potential of play and playfulness to enhance human capacity to respond to adversity and cope with the stresses of everyday life. In play we build a repertoire of adaptive, flexible responses to unexpected events, in an environment separated from the real consequences of those events. Playfulness helps us maintain social and emotional equilibrium in times of rapid change and stress. Through play, we experience flow-A feeling of being taken to another place, out of time, where we have controlled of the world. This paper argues that spontaneous free play, controlled and directed by children and understood from the child's perspective, contributes to children's subjective experience of well-being, building a foundation for life-long social and emotional health. The paradoxical nature of young children's spontaneous free play is explored. Adaptability, control, flexibility, resilience and balance result from the experience of uncertainty, unpredictability, novelty and non-productivity. These essential dimensions of young children's spontaneous free play typically produce play which is experienced by adults as chaotic, nonsensical and disruptive. The article concludes with a preliminary discussion of the challenges and possibilities of providing for spontaneous free play indoors, in early childhood care and education programs.

[Bone metabolism in human space flight and bed rest study].

PubMed

Ohshima, Hiroshi; Mukai, Chiaki

2008-09-01

Japanese Experiment Module "KIBO" is Japan's first manned space facility and will be operated as part of the international space station (ISS) . KIBO operations will be monitored and controlled from Tsukuba Space Center. In Japan, after the KIBO element components are fully assembled and activated aboard the ISS, Japanese astronauts will stay on the ISS for three or more months, and full-scale experiment operations will begin. Bone loss and renal stone are significant medical concerns for long duration human space flight. This paper will summarize the results of bone loss, calcium balance obtained from the American and Russian space programs, and ground-base analog bedrest studies. Current in-flight training program, nutritional recommendations and future countermeasure plans for station astronauts are also described.

Effect of chronic low level manganese exposure on postural balance: A pilot study of residents in southwest Ohio

PubMed Central

Standridge, J. S.; Bhattacharya, Amit; Succop, Paul; Cox, Cyndy; Haynes, Erin

2009-01-01

OBJECTIVE The objective of this study was to determine the effect of non-occupational exposure to manganese on postural balance. METHODS Residents living near a ferromanganese refinery provided hair and blood samples after postural balance testing. The relationship between hair manganese and postural balance was analyzed with logistic regression. Following covariate adjustment, postural balance was compared with control data by analysis of covariance. RESULTS Mean hair manganese was 4.4 µg/g. A significantly positive association was found between hair manganese and sway area (EO, p=0.05; EC, p=0.04) and sway length (EO, p=0.05; EC, p=0.04). Postural balance of residents was significantly larger than controls in 5 out of 8 postural balance outcomes. CONCLUSION Preliminary findings suggest subclinical impairment in postural balance among residents chronically exposed to ambient Mn. A prospective study with a larger sample size is warranted. PMID:19092498

Knee flexor strength and balance control impairment may explain declines during prolonged walking in women with mild multiple sclerosis.

PubMed

Ramari, Cintia; Moraes, Andréa G; Tauil, Carlos B; von Glehn, Felipe; Motl, Robert; de David, Ana C

2018-02-01

Physiological factors such as muscle weakness and balance could explain declines in walking distance by multiple sclerosis (MS) patients. The purpose of this study was to characterize levels and examine associations among decline in walking distance, balance and muscular strength in women with mild MS. Participants included 28 women with mild relapsing-remitting MS and 21 women without MS. We executed the 6-min walk test (6MWT) to verify declines in walking distance. Isokinetic knee flexion (KF) and extension (KE) muscle strength was measured using a dynamometer. Balance was quantified using a force platform, with eyes open and closed, on a rigid and foam surface. The MS patients presented declines in walking, lower KF muscle strength, and worse balance than controls. KF strength and balance correlated with walking in the MS group. The KF strength explained differences between groups in walking. The KF strength and balance presented as predictors of walking slowing down in the 6MWT, in mild MS. Women with mild MS have strength impairment of knee flexor muscles and balance control impairment that may explain walking related motor fatigability during prolonged walking. Copyright © 2018 Elsevier B.V. All rights reserved.

Balance training program is highly effective in improving functional status and reducing the risk of falls in elderly women with osteoporosis: a randomized controlled trial

PubMed Central

Madureira, M. M.; Takayama, L.; Gallinaro, A. L.; Caparbo, V. F.; Costa, R. A.

2006-01-01

Introduction The purpose of this study was to investigate the effect of a 12-month Balance Training Program on balance, mobility and falling frequency in women with osteoporosis. Methods Sixty-six consecutive elderly women were selected from the Osteometabolic Disease Outpatient Clinic and randomized into 2 groups: the ‘Intervention’, submitted for balance training; and the ‘Control’, without intervention. Balance, mobility and falling frequency were evaluated before and at the end of the trial, using the Berg Balance Scale (BBS), the Clinical Test Sensory Interaction Balance (CTSIB) and the Timed “Up & Go” Test (TUGT). Intervention used techniques to improve balance consisting of a 1-hour session each week and a home-based exercise program. Results Sixty women completed the study and were analyzed. The BBS difference was significant higher in the Intervention group compared to Control (5.5 ± 5.67 vs −0.5 ± 4.88 score, p < 0.001). Similarly, the number of patients in the Intervention group presented improvement in two conditions of CTSIB compared to Control (eyes closed and unstable surface condition: 13 vs one patient, p < 0.001 and eyes open, visual conflict and unstable surface condition: 12 vs one patient, p < 0.001). Additionally, the differences between the TUGT were reduced in the Intervention group compared to Control (−3.65 ± 3.61 vs 2.27 ± 7.18 seconds, p< 0.001). Notably, this improvement was paralleled by a reduction in the number of falls/patient in the Intervention group compared to Control (−0.77 ± 1.76 vs 0.33 ± 0.96, p = 0.018). Conclusion This longitudinal prospective study demonstrated that an intervention using balance training is effective in improving functional and static balance, mobility and falling frequency in elderly women with osteoporosis. PMID:17089080

ARC-1995-AC95-0368-3

NASA Image and Video Library

1995-10-27

Dr Murial Ross's Virtual Reality Application for Neuroscience Research Biocomputation. To study human disorders of balance and space motion sickness. Shown here is a 3D reconstruction of a nerve ending in inner ear, nature's wiring of balance organs.

Role of VGF-derived carboxy-terminal peptides in energy balance and reproduction: analysis of "humanized" knockin mice expressing full-length or truncated VGF.

PubMed

Sadahiro, Masato; Erickson, Connor; Lin, Wei-Jye; Shin, Andrew C; Razzoli, Maria; Jiang, Cheng; Fargali, Samira; Gurney, Allison; Kelley, Kevin A; Buettner, Christoph; Bartolomucci, Alessandro; Salton, Stephen R

2015-05-01

Targeted deletion of VGF, a secreted neuronal and endocrine peptide precursor, produces lean, hypermetabolic, and infertile mice that are resistant to diet-, lesion-, and genetically-induced obesity and diabetes. Previous studies suggest that VGF controls energy expenditure (EE), fat storage, and lipolysis, whereas VGF C-terminal peptides also regulate reproductive behavior and glucose homeostasis. To assess the functional equivalence of human VGF(1-615) (hVGF) and mouse VGF(1-617) (mVGF), and to elucidate the function of the VGF C-terminal region in the regulation of energy balance and susceptibility to obesity, we generated humanized VGF knockin mouse models expressing full-length hVGF or a C-terminally deleted human VGF(1-524) (hSNP), encoded by a single nucleotide polymorphism (rs35400704). We show that homozygous male and female hVGF and hSNP mice are fertile. hVGF female mice had significantly increased body weight compared with wild-type mice, whereas hSNP mice have reduced adiposity, increased activity- and nonactivity-related EE, and improved glucose tolerance, indicating that VGF C-terminal peptides are not required for reproductive function, but 1 or more specific VGF C-terminal peptides are likely to be critical regulators of EE. Taken together, our results suggest that human and mouse VGF proteins are largely functionally conserved but that species-specific differences in VGF peptide function, perhaps a result of known differences in receptor binding affinity, likely alter the metabolic phenotype of hVGF compared with mVGF mice, and in hSNP mice in which several C-terminal VGF peptides are ablated, result in significantly increased activity- and nonactivity-related EE.

Control of movement initiation underlies the development of balance

PubMed Central

Ehrlich, David E.; Schoppik, David

2017-01-01

Summary Balance arises from the interplay of external forces acting on the body and internally generated movements. Many animal bodies are inherently unstable, necessitating corrective locomotion to maintain stability. Understanding how developing animals come to balance remains a challenge. Here we study the interplay between environment, sensation, and action as balance develops in larval zebrafish. We first model the physical forces that challenge underwater balance and experimentally confirm that larvae are subject to constant destabilization. Larvae propel in swim bouts that, we find, tend to stabilize the body. We confirm the relationship between locomotion and balance by changing larval body composition, exacerbating instability and eliciting more frequent swimming. Intriguingly, developing zebrafish come to control the initiation of locomotion, swimming preferentially when unstable, thus restoring preferred postures. To test the sufficiency of locomotor-driven stabilization and the developing control of movement timing, we incorporate both into a generative model of swimming. Simulated larvae recapitulate observed postures and movement timing across early development, but only when locomotor-driven stabilization and control of movement initiation are both utilized. We conclude the ability to move when unstable is the key developmental improvement to balance in larval zebrafish. Our work informs how emerging sensorimotor ability comes to impact how and why animals move when they do. PMID:28111151

The effect of modified trampoline training on balance, gait, and falls efficacy of stroke patients

PubMed Central

Hahn, Joohee; Shin, Seonhae; Lee, Wanhee

2015-01-01

[Purpose] This research was conducted to investigate the effects of modified trampoline training on the balance, gait, and falls efficacy of stroke patients. [Subjects] Twenty-four stroke patients participated in this study. The subjects were randomly allocated to one of two groups: the trampoline group (n=12) or the control group (n=12). [Methods] Both groups participated in conventional physical therapy for thirty minutes per day, three times a week for six weeks. The trampoline group also took part in trampoline training for thirty minutes per day, three times a week for six weeks. We evaluated balance (Berg balance scale, timed up and go test), gait (dynamic gait index), and falls efficacy (falls efficacy scale-K) to confirm the effects of the intervention. [Results] Both the trampoline and the control group showed significant improvements in balance, gait, and falls efficacy compared to before the intervention, and the improvements were significantly greater in the trampoline group than in the control group. [Conclusion] Modified trampoline training resulted in significantly improved balance, dynamic gait, and falls efficacy of stroke patients compared to the control group. These results suggest that modified trampoline training is feasible and effective at improving balance, dynamic gait, and falls efficacy after stroke. PMID:26696696

The effect of modified trampoline training on balance, gait, and falls efficacy of stroke patients.

PubMed

Hahn, Joohee; Shin, Seonhae; Lee, Wanhee

2015-11-01

[Purpose] This research was conducted to investigate the effects of modified trampoline training on the balance, gait, and falls efficacy of stroke patients. [Subjects] Twenty-four stroke patients participated in this study. The subjects were randomly allocated to one of two groups: the trampoline group (n=12) or the control group (n=12). [Methods] Both groups participated in conventional physical therapy for thirty minutes per day, three times a week for six weeks. The trampoline group also took part in trampoline training for thirty minutes per day, three times a week for six weeks. We evaluated balance (Berg balance scale, timed up and go test), gait (dynamic gait index), and falls efficacy (falls efficacy scale-K) to confirm the effects of the intervention. [Results] Both the trampoline and the control group showed significant improvements in balance, gait, and falls efficacy compared to before the intervention, and the improvements were significantly greater in the trampoline group than in the control group. [Conclusion] Modified trampoline training resulted in significantly improved balance, dynamic gait, and falls efficacy of stroke patients compared to the control group. These results suggest that modified trampoline training is feasible and effective at improving balance, dynamic gait, and falls efficacy after stroke.

Acute Effects of Capsaicin on Energy Expenditure and Fat Oxidation in Negative Energy Balance

PubMed Central

Janssens, Pilou L. H. R.; Hursel, Rick; Martens, Eveline A. P.; Westerterp-Plantenga, Margriet S.

2013-01-01

Background Addition of capsaicin (CAPS) to the diet has been shown to increase energy expenditure; therefore capsaicin is an interesting target for anti-obesity therapy. Aim We investigated the 24 h effects of CAPS on energy expenditure, substrate oxidation and blood pressure during 25% negative energy balance. Methods Subjects underwent four 36 h sessions in a respiration chamber for measurements of energy expenditure, substrate oxidation and blood pressure. They received 100% or 75% of their daily energy requirements in the conditions ‘100%CAPS’, ‘100%Control’, ‘75%CAPS’ and ‘75%Control’. CAPS was given at a dose of 2.56 mg (1.03 g of red chili pepper, 39,050 Scoville heat units (SHU)) with every meal. Results An induced negative energy balance of 25% was effectively a 20.5% negative energy balance due to adapting mechanisms. Diet-induced thermogenesis (DIT) and resting energy expenditure (REE) at 75%CAPS did not differ from DIT and REE at 100%Control, while at 75%Control these tended to be or were lower than at 100%Control (p = 0.05 and p = 0.02 respectively). Sleeping metabolic rate (SMR) at 75%CAPS did not differ from SMR at 100%CAPS, while SMR at 75%Control was lower than at 100%CAPS (p = 0.04). Fat oxidation at 75%CAPS was higher than at 100%Control (p = 0.03), while with 75%Control it did not differ from 100%Control. Respiratory quotient (RQ) was more decreased at 75%CAPS (p = 0.04) than at 75%Control (p = 0.05) when compared with 100%Control. Blood pressure did not differ between the four conditions. Conclusion In an effectively 20.5% negative energy balance, consumption of 2.56 mg capsaicin per meal supports negative energy balance by counteracting the unfavorable negative energy balance effect of decrease in components of energy expenditure. Moreover, consumption of 2.56 mg capsaicin per meal promotes fat oxidation in negative energy balance and does not increase blood pressure significantly. Trial Registration Nederlands Trial Register; registration number NTR2944 PMID:23844093

Time course and dimensions of postural control changes following neuromuscular training in youth field hockey athletes.

PubMed

Zech, Astrid; Klahn, Philipp; Hoeft, Jon; zu Eulenburg, Christine; Steib, Simon

2014-02-01

Injury prevention effects of neuromuscular training have been partly attributed to postural control adaptations. Uncertainty exists regarding the magnitude of these adaptations and on how they can be adequately monitored. The objective was to determine the time course of neuromuscular training effects on functional, dynamic and static balance measures. Thirty youth (14.9 ± 3 years) field hockey athletes were randomised to an intervention or control group. The intervention included a 20-min neuromuscular warm-up program performed twice weekly for 10 weeks. Balance assessments were performed at baseline, week three, week six and post-intervention. They included the star excursion balance test (SEBT), balance error scoring system (BESS), jump-landing time to stabilization (TTS) and center of pressure (COP) sway velocity during single-leg standing. No baseline differences were found between groups in demographic data and balance measures. Adherence was at 86%. All balance measures except the medial-lateral TTS improved significantly over time (p < 0.05) in both groups. Significant group by time interactions were found for the BESS score (p < 0.001). The intervention group showed greater improvements (69.3 ± 10.3%) after 10 weeks in comparison to controls (31.8 ± 22.1%). There were no significant group by time interactions in the SEBT, TTS and COP sway velocity. Neuromuscular training was effective in improving postural control in youth team athletes. However, this effect was not reflected in all balance measures suggesting that the neuromuscular training did not influence all dimensions of postural control. Further studies are needed to confirm the potential of specific warm-up programs to improve postural control.

Locomotor skills and balance strategies in adolescents idiopathic scoliosis.

PubMed

Mallau, Sophie; Bollini, Gérard; Jouve, Jean-Luc; Assaiante, Christine

2007-01-01

Locomotor balance control assessment was performed to study the effect of idiopathic scoliosis on head-trunk coordination in 17 patients with adolescent idiopathic scoliosis (AIS) and 16 control subjects. The aim of this study was to explore the functional effects of structural spinal deformations like idiopathic scoliosis on the balance strategies used during locomotion. Up to now, the repercussion of the idiopathic scoliosis on head-trunk coordination and balance strategies during locomotion is relatively unknown. Seventeen patients with AIS (mean age 14 years 3 months, 10 degrees < Cobb angle > 30 degrees) and 16 control subjects (mean age 14 years 1 month) were tested during various locomotor tasks: walking on the ground, walking on a line, and walking on a beam. Balance control was examined in terms of rotation about the vertical axis (yaw) and on a frontal plane (roll). Kinematics of foot, pelvis, trunk, shoulder, and head rotations were measured with an automatic optical TV image processor in order to calculate angular dispersions and segmental stabilizations. Decreasing the walking speed is the main adaptive strategy used in response to balance problems in control subjects as well as patients with AIS. However, patients with AIS performed walking tasks more slowly than normal subjects (around 15%). Moreover, the pelvic stabilization is preserved, despite the structural changes affecting the spine. Lastly, the biomechanical defect resulting from idiopathic scoliosis mainly affects the yaw head stabilization during locomotion. Patients with AIS show substantial similarities with control subjects in adaptive strategies relative to locomotor velocity as well as balance control based on segmental stabilization. In contrast, the loss of the yaw head stabilization strategies, mainly based on the use of vestibular information, probably reflects the presence of vestibular deficits in the patients with AIS.

Balance control during gait initiation: State-of-the-art and research perspectives.

PubMed

Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis

2017-11-18

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation - the transient period between the quiet standing posture and steady state walking - is a functional task that is classically used in the literature to investigate how the central nervous system (CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a pre-requisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on: (1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and (2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward: (1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and (2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices.

Balance control during gait initiation: State-of-the-art and research perspectives

PubMed Central

Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis

2017-01-01

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation - the transient period between the quiet standing posture and steady state walking - is a functional task that is classically used in the literature to investigate how the central nervous system (CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a pre-requisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on: (1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and (2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward: (1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and (2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices. PMID:29184756

Home-based virtual reality balance training and conventional balance training in Parkinson's disease: A randomized controlled trial.

PubMed

Yang, Wen-Chieh; Wang, Hsing-Kuo; Wu, Ruey-Meei; Lo, Chien-Shun; Lin, Kwan-Hwa

2016-09-01

Virtual reality has the advantage to provide rich sensory feedbacks for training balance function. This study tested if the home-based virtual reality balance training is more effective than the conventional home balance training in improving balance, walking, and quality of life in patients with Parkinson's disease (PD). Twenty-three patients with idiopathic PD were recruited and underwent twelve 50-minute training sessions during the 6-week training period. The experimental group (n = 11) was trained with a custom-made virtual reality balance training system, and the control group (n = 12) was trained by a licensed physical therapist. Outcomes were measured at Week 0 (pretest), Week 6 (posttest), and Week 8 (follow-up). The primary outcome was the Berg Balance Scale. The secondary outcomes included the Dynamic Gait Index, timed Up-and-Go test, Parkinson's Disease Questionnaire, and the motor score of the Unified Parkinson's Disease Rating Scale. The experimental and control groups were comparable at pretest. After training, both groups performed better in the Berg Balance Scale, Dynamic Gait Index, timed Up-and-Go test, and Parkinson's Disease Questionnaire at posttest and follow-up than at pretest. However, no significant differences were found between these two groups at posttest and follow-up. This study did not find any difference between the effects of the home-based virtual reality balance training and conventional home balance training. The two training options were equally effective in improving balance, walking, and quality of life among community-dwelling patients with PD. Copyright © 2015. Published by Elsevier B.V.

Longitudinal Study Evaluating Postural Balance of Young Athletes.

PubMed

Steinberg, Nili; Nemet, Dan; Pantanowitz, Michal; Zeev, Aviva; Hallumi, Monder; Sindiani, Mahmood; Meckel, Yoav; Eliakim, Alon

2016-02-01

Repeated anaerobic conditions during athletic performance may cause general and local fatigue that result in postural balance deficit. Evidence suggests that improved postural balance during athletic training may decrease the risk for fallings and traumatic injuries among athletes. Twenty athletes (12 girls, 8 boys) and 20 controls (12 girls, 8 boys) ages 10-15 years participated in the current study. All athletes were active in an 8-month physical activity program, 3 times per week for 90 min., specific to basketball, soccer, or athletic training. The control children participated in physical education at school only, with no involvement in organized extracurricular sports. All participants were evaluated for postural balance in three assessments over one year (at 4-mo intervals); the Interactive Balance System machine (Tetrax device) was used to assess balance at three test times (pre-, post-, and 10 min) after a session of a repeated sprint anaerobic test, consisting of 12 × 20 m run starting every 20 sec. The athletes had better postural balance than controls. There were different group patterns of change over the sessions; a significant interaction of session and group indicated that postural balance of the groups differed. The contribution of low sway frequencies (F1) and high sway frequencies (F6) differed between the controls and the athletes group. Results suggested that although athletes had better postural balance, improvement should be encouraged during training over the sessions and seasons, with special awareness of the balance deficit that occurs immediately after anaerobic stress and at the end of the season, to decrease the risk of injuries. © The Author(s) 2016.

Microprocessor-Controlled Laser Balancing System

NASA Technical Reports Server (NTRS)

Demuth, R. S.

1985-01-01

Material removed by laser action as part tested for balance. Directed by microprocessor, laser fires appropriate amount of pulses in correct locations to remove necessary amount of material. Operator and microprocessor software interact through video screen and keypad; no programing skills or unprompted system-control decisions required. System provides complete and accurate balancing in single load-and-spinup cycle.

Effects of long-term balance training with vibrotactile sensory augmentation among community-dwelling healthy older adults: a randomized preliminary study.

PubMed

Bao, Tian; Carender, Wendy J; Kinnaird, Catherine; Barone, Vincent J; Peethambaran, Geeta; Whitney, Susan L; Kabeto, Mohammed; Seidler, Rachael D; Sienko, Kathleen H

2018-01-18

Sensory augmentation has been shown to improve postural stability during real-time balance applications. Limited long-term controlled studies have examined retention of balance improvements in healthy older adults after training with sensory augmentation has ceased. This pilot study aimed to assess the efficacy of long-term balance training with and without sensory augmentation among community-dwelling healthy older adults. Twelve participants (four males, eight females; 75.6 ± 4.9 yrs) were randomly assigned to the experimental group (n = 6) or control group (n = 6). Participants trained in their homes for eight weeks, completing three 45-min exercise sessions per week using smart phone balance trainers that provided written, graphic, and video guidance, and monitored trunk sway. During each session, participants performed six repetitions of six exercises selected from five categories (static standing, compliant surface standing, weight shifting, modified center of gravity, and gait). The experimental group received vibrotactile sensory augmentation for four of the six repetitions per exercise via the smart phone balance trainers, while the control group performed exercises without sensory augmentation. The smart phone balance trainers sent exercise performance data to a physical therapist, who recommended exercises on a weekly basis. Balance performance was assessed using a battery of clinical balance tests (Activity Balance Confidence Scale, Sensory Organization Test, Mini Balance Evaluation Systems Test, Five Times Sit to Stand Test, Four Square Step Test, Functional Reach Test, Gait Speed Test, Timed Up and Go, and Timed Up and Go with Cognitive Task) before training, after four weeks of training, and after eight weeks of training. Participants in the experimental group were able to use vibrotactile sensory augmentation independently in their homes. After training, the experimental group had significantly greater improvements in Sensory Organization Test and Mini Balance Evaluation Systems Test scores than the control group. Significant improvement was also observed for Five Times Sit to Stand Test duration within the experimental group, but not in the control group. No significant improvements between the two groups were observed in the remaining clinical outcome measures. The findings of this study support the use of sensory augmentation devices by community-dwelling healthy older adults as balance rehabilitation tools, and indicate feasibility of telerehabilitation therapy with reduced input from clinicians.

Complete low-cost implementation of a teleoperated control system for a humanoid robot.

PubMed

Cela, Andrés; Yebes, J Javier; Arroyo, Roberto; Bergasa, Luis M; Barea, Rafael; López, Elena

2013-01-24

Humanoid robotics is a field of a great research interest nowadays. This work implements a low-cost teleoperated system to control a humanoid robot, as a first step for further development and study of human motion and walking. A human suit is built, consisting of 8 sensors, 6 resistive linear potentiometers on the lower extremities and 2 digital accelerometers for the arms. The goal is to replicate the suit movements in a small humanoid robot. The data from the sensors is wirelessly transmitted via two ZigBee RF configurable modules installed on each device: the robot and the suit. Replicating the suit movements requires a robot stability control module to prevent falling down while executing different actions involving knees flexion. This is carried out via a feedback control system with an accelerometer placed on the robot's back. The measurement from this sensor is filtered using Kalman. In addition, a two input fuzzy algorithm controlling five servo motors regulates the robot balance. The humanoid robot is controlled by a medium capacity processor and a low computational cost is achieved for executing the different algorithms. Both hardware and software of the system are based on open platforms. The successful experiments carried out validate the implementation of the proposed teleoperated system.

Complete Low-Cost Implementation of a Teleoperated Control System for a Humanoid Robot

PubMed Central

Cela, Andrés; Yebes, J. Javier; Arroyo, Roberto; Bergasa, Luis M.; Barea, Rafael; López, Elena

2013-01-01

Humanoid robotics is a field of a great research interest nowadays. This work implements a low-cost teleoperated system to control a humanoid robot, as a first step for further development and study of human motion and walking. A human suit is built, consisting of 8 sensors, 6 resistive linear potentiometers on the lower extremities and 2 digital accelerometers for the arms. The goal is to replicate the suit movements in a small humanoid robot. The data from the sensors is wirelessly transmitted via two ZigBee RF configurable modules installed on each device: the robot and the suit. Replicating the suit movements requires a robot stability control module to prevent falling down while executing different actions involving knees flexion. This is carried out via a feedback control system with an accelerometer placed on the robot's back. The measurement from this sensor is filtered using Kalman. In addition, a two input fuzzy algorithm controlling five servo motors regulates the robot balance. The humanoid robot is controlled by a medium capacity processor and a low computational cost is achieved for executing the different algorithms. Both hardware and software of the system are based on open platforms. The successful experiments carried out validate the implementation of the proposed teleoperated system. PMID:23348029

Mathematical modeling of the human body during water replacement and dehydration: body water changes.

PubMed

Downey, D; Seagrave, R C

2000-03-01

A model of the human body that integrates the variables involved in temperature regulation and blood gas transport within the cardiovascular and respiratory systems is presented here. It expands upon previous work to describe the competition between skin and muscles when both require increased blood flows during exercise and/or heat stress. First, a detailed study of the control relations used to predict skin blood flow was undertaken. Four other control relations employed in the model were also examined and modified as indicated by empirical results found in literature. Internal responses to exercise and/or heat stress can affect both thermoregulation and the cardiorespiratory system. Dehydration was studied in addition to complete water replacement during similar environmental and exercise situations. Control relations for skin blood flow and evaporative heat loss were modified and a water balance was added to study how the loss of water through sweat can be limiting. Runoff from sweating as a function of relative humidity was introduced along with evaporation, and these results were compared to data to validate the model.

Apoptosis in the homeostasis of the immune system and in human immune mediated diseases.

PubMed

Giovannetti, A; Pierdominici, M; Di Iorio, A; Cianci, R; Murdaca, G; Puppo, F; Pandolfi, F; Paganelli, R

2008-01-01

The immune system has evolved sophisticated mechanisms controlling the development of responses to dangerous antigens while avoiding unnecessary attacks to innocuous, commensal or self antigens. The risk of autoimmunity is continuously checked and balanced against the risk of succumbing to exogenous infectious agents. It is therefore of paramount importance to understand the molecular events linking the breakdown of tolerance and the development of immunodeficiency. Apoptotic mechanisms are used to regulate the development of thymocytes, the shaping of T cell repertoire, its selection and the coordinate events leading to immune responses in the periphery. Moreover, they are at the heart of the homeostatic controls restoring T cell numbers and establishing T cell memory. T lymphocytes shift continuously from survival to death signals to ensure immune responsiveness without incurring in autoimmune damage. In this review we shall consider some key facts on the relationship of lymphopenia to autoreactivity, the mechanisms controlling positive and negative selection in the thymus, the role of apoptosis in selected primary immunodeficiency states and in systemic and organ-specific autoimmunity, with examples from human diseases and their animal models.

Whole-body vibration training improves balance, muscle strength and glycosylated hemoglobin in elderly patients with diabetic neuropathy.

PubMed

Lee, Kyoungjin; Lee, Seungwon; Song, Changho

2013-12-01

Elderly patients with diabetes and peripheral neuropathy are more likely to experience falls. However, the information available on how such falls can be prevented is scarce. We investigated the effects of whole-body vibration (WBV) combined with a balance exercise program on balance, muscle strength, and glycosylated hemoglobin (HbA1c) in elderly patients with diabetic peripheral neuropathy. Fifty-five elderly patients with diabetic neuropathy were randomly assigned to WBV with balance exercise group, balance exercise (BE) group, and control group. The WBV and BE groups performed the balance exercise program for 60 min per day, 2 times per week, for 6 weeks. Further, the WBV group performed WBV training (up to 3 × 3 min, 3 times per week, for 6 weeks). The control group did not participate in any training. The main outcome measures were assessed at baseline and after 6 weeks of training; namely, we assessed the postural sway and one leg stance (OLS) for static balance; Berg balance scale (BBS), timed up-and-go (TUG) test, and functional reach test (FRT) for dynamic balance; five-times-sit-to-stand (FTSTS) test for muscle strength; and HbA1c for predicting the progression of diabetes. Significant improvements were noted in the static balance, dynamic balance, muscle strength, and HbA1c in the WBV group, compared to the BE and control groups (P < 0.05). Thus, in combination with the balance exercise program, the short-term WBV therapy is beneficial in improving balance, muscle strength and HbA1c, in elderly patients with diabetic neuropathy who are at high risk for suffering falls.

Caloric Restriction in Older Adults-Differential Effects of Weight Loss and Reduced Weight on Brain Structure and Function.

PubMed

Prehn, Kristin; Jumpertz von Schwartzenberg, Reiner; Mai, Knut; Zeitz, Ulrike; Witte, A Veronica; Hampel, Dierk; Szela, Anna-Maria; Fabian, Sonja; Grittner, Ulrike; Spranger, Joachim; Flöel, Agnes

2017-03-01

Dietary modifications such as caloric restriction (CR) have been suggested as a means to improve memory and prevent age-related decline. However, it is unclear whether those effects remain stable over time or are related specifically to negative energy balance during the weight loss phase of CR. Using a randomized interventional design, we investigated changes in recognition memory and neural correlates in postmenopausal obese women (n = 19): 1) after intense weight loss in the course of a 12-week low-caloric diet (reduced body weight and negative energy balance) and 2) after having sustained the reduced weight over 4 more weeks (reduced body weight, but energy balance equilibrium). Participants were contrasted to a control group (n = 18) instructed not to change dietary habits. In the CR group, we found improved recognition memory, paralleled by increased gray matter volume in inferior frontal gyrus and hippocampus, and augmented hippocampal resting-state functional connectivity to parietal areas. Moreover, effects were specific for transient negative energy balance and could not be detected after subsequent weight maintenance. Our data demonstrate for the first time in humans that beneficial effects of CR on brain structure and function are due to weight loss rather than an overall reduced weight. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

The effect of Nintendo® Wii® on balance in people with multiple sclerosis: a pilot randomized control study.

PubMed

Brichetto, Giampaolo; Spallarossa, Patricio; de Carvalho, Maria L Lopes; Battaglia, Mario A

2013-08-01

Improvement of sensory strategies is a relevant part of balance rehabilitation in multiple sclerosis (MS). This study aimed to Assess the effectiveness of visual-feedback exercises in improving balance in MS. We divided 36 patients into Wii and control-treated groups that underwent balance rehabilitation. Outcomes were obtained for Berg Balance Scale (BBS), Modified Fatigue Impact Scale, and sway area under conditions of opened and closed eyes. BBS showed a statistically significant improvement (from 49.6 to 54.6 points, p < 0.05) in the Wii group. Interactive visual-feedback exercises such as Wii could be more effective than the current standard protocol in improving balance disorders in MS.

The Effects of Slackline Balance Training on Postural Control in Older Adults.

PubMed

Thomas, Monika; Kalicinski, Michael

2016-07-01

The present study investigated whether slackline training enhances postural control in older adults. Twenty-four participants were randomized into an intervention and a control group. The intervention group received 6 weeks of slackline training, two times per week. Pre-post measurement included the time of different standing positions on a balance platform with and without an external disturbance and the acceleration of the balance platform. Results showed significantly improved standing times during one-leg stance without external disturbance and a significantly reduced acceleration of the balance platform for the intervention group after the training period during tandem stance with and without an external disturbance. We conclude that slackline training in older adults has a positive impact on postural control and thus on the reduction of fall risk.

Development of a two-dimensional skin friction balance nulling circuit using multivariable control theory

NASA Technical Reports Server (NTRS)

Tripp, John S.; Patek, Stephen D.

1988-01-01

Measurement of planar skin friction forces in aerodynamic testing currently requires installation of two perpendicularly mounted, single-axis balances; consequently, force components must be sensed at two distinct locations. A two-axis instrument developed at the Langley Research Center to overcome this disadvantage allows measurement of a two-dimensional force at one location. This paper describes a feedback-controlled nulling circuit developed for the NASA two-axis balance which, without external compensation, is inherently unstable because of its low friction mechanical design. Linear multivariable control theory is applied to an experimentally validated mathematical model of the balance to synthesize a state-variable feedback control law. Pole placement techniques and computer simulation studies are employed to select eigenvalues which provide ideal transient response with decoupled sensing dynamics.

The relationship between Fibroblast Growth Factor-21 and characteristic parameters related to energy balance in dairy cows.

PubMed

Xu, Chuang; Xu, Qiushi; Chen, Yuanyuan; Yang, Wei; Xia, Cheng; Yu, Hongjiang; Zhu, Kuilin; Shen, Taiyu; Zhang, Ziyang

2015-10-24

Negative energy balance (NEB) is a common pathological foundation of ketosis and fatty liver. Liver and fat tissue are the major organs of lipid metabolism and take part in modulating lipid oxidative capacity and energy demands, which is also a key metabolic pathway that regulates NEB develop during perinatal period. Fibroblast growth factor-21 (FGF-21) is a recently discovered protein hormone that plays an important and specific regulating role in adipose lipid metabolism and liver gluconeogenesis for human and mouse. Our aim is to investigate the variation and relationship between serum FGF-21 concentration and characteristic parameters related to negative energy balance in different energy metabolism state. In this research, five non-pregnant, non-lactating Holstein-Friesian dairy cows were randomly allocated into two groups. The interventions were a controlled-energy diet (30% of maintenance energy requirements) and a moderate-energy diet (120% of predicted energy requirements) that lasted for the duration of the experiment. We measured biochemical parameters, serum FGF-21, leptin and insulin levels by commercial ELISA kits. The results showed that serum FGF-21 levels were significantly higher in both groups treated with a controlled-energy diet, while FGF-21 levels in both groups treated with moderate-energy diet were low. FGF-21 levels exhibited a significant positive correlation with serum leptin levels, while an inverse relationship was found between FGF-21 and blood glucose and β-hydroxybutyrate acid (BHBA) levels. An increase in FGF-21 levels after a controlled-energy diet treatment may contribute to a positive metabolic effect which could result in a new theoretical and practical basis for the preventive strategy of dairy cows with NEB.

Design and Sizing of the Air Revitalization System for Altair Lunar Lander

NASA Technical Reports Server (NTRS)

Allada, Rama Kumar

2009-01-01

Designing closed-loop Air Revitalization Systems (ARS) for human spaceflight applications requires a delicate balance between designing for system robustness while minimizing system power and mass requirements. This presentation will discuss the design of the ARS for the Altair Lunar Lander. The presentation will illustrate how dynamic simulations, using Aspen Custom Modeler, were used to develop a system configuration with the ability to control atmospheric conditions under a wide variety of circumstances while minimizing system mass/volume and the impact on overall power requirements for the Lander architecture.

Validity and Reliability of Wii Fit Balance Board for the Assessment of Balance of Healthy Young Adults and the Elderly

PubMed Central

Chang, Wen-Dien; Chang, Wan-Yi; Lee, Chia-Lun; Feng, Chi-Yen

2013-01-01

[Purpose] Balance is an integral part of human ability. The smart balance master system (SBM) is a balance test instrument with good reliability and validity, but it is expensive. Therefore, we modified a Wii Fit balance board, which is a convenient balance assessment tool, and analyzed its reliability and validity. [Subjects and Methods] We recruited 20 healthy young adults and 20 elderly people, and administered 3 balance tests. The correlation coefficient and intraclass correlation of both instruments were analyzed. [Results] There were no statistically significant differences in the 3 tests between the Wii Fit balance board and the SBM. The Wii Fit balance board had a good intraclass correlation (0.86–0.99) for the elderly people and positive correlations (r = 0.58–0.86) with the SBM. [Conclusions] The Wii Fit balance board is a balance assessment tool with good reliability and high validity for elderly people, and we recommend it as an alternative tool for assessing balance ability. PMID:24259769

An evaluation of a nurse-led rehabilitation programme (the ProBalance Programme) to improve balance and reduce fall risk of community-dwelling older people: A randomised controlled trial.

PubMed

Gouveia, Bruna Raquel; Gonçalves Jardim, Helena; Martins, Maria Manuela; Gouveia, Élvio Rúbio; de Freitas, Duarte Luís; Maia, José António; Rose, Debra J

2016-04-01

This study aims to assess the effect of a nurse-led rehabilitation programme (the ProBalance Programme) on balance and fall risk of community-dwelling older people from Madeira Island, Portugal. Single-blind, randomised controlled trial. University laboratory. Community-dwelling older people, aged 65-85, with balance impairments. Participants were randomly allocated to an intervention group (IG; n=27) or a wait-list control group (CG; n=25). A rehabilitation nursing programme included gait, balance, functional training, strengthening, flexibility, and 3D training. One trained rehabilitation nurse administered the group-based intervention over a period of 12 weeks (90min sessions, 2 days per week). A wait-list control group was instructed to maintain their usual activities during the same time period. Balance was assessed using the Fullerton Advanced Balance (FAB) scale. The time points for assessment were at zero (pre-test), 12 (post-test), and 24 weeks (follow up). Changes in the mean (SD) FAB scale scores immediately following the 12-week intervention were 5.15 (2.81) for the IG and -1.45 (2.80) for the CG. At follow-up, the mean (SD) change scores were -1.88 (1.84) and 0.75 (2.99) for the IG and CG, respectively. The results of a mixed between-within subjects analysis of variance, controlling for physical activity levels at baseline, revealed a significant interaction between group and time (F (2, 42)=27.89, p<0.001, Partial Eta Squared=0.57) and a main effect for time (F (2, 43)=3.76, p=0.03, Partial Eta Squared=0.15), with both groups showing changes in the mean FAB scale scores across the three time periods. A significant main effect comparing the two groups (F (1, 43)=21.90, p<0.001, Partial Eta Squared=0.34) confirmed a clear positive effect of the intervention when compared to the control. This study demonstrated that the rehabilitation nursing programme was effective in improving balance and reducing fall risk in a group of older people with balance impairment, immediately after the intervention. A decline in balance was observed for the IG after a period of no intervention. ACTRN12612000301864. Copyright © 2015 Elsevier Ltd. All rights reserved.

Daily Bicycling in Older Adults May Be Effective to Reduce Fall Risks - A Case Control Study.

PubMed

Batcir, Shani; Melzer, Itshak

2018-01-18

Older adults gain many health benefits from riding bicycles regularly. We aimed to explore whether older persons who ride bicycles regularly have better balance than controls. Balance control and voluntary stepping were assessed in 20 older adults aged 65 to 85 who live in an agricultural community village who regularly ride bicycles (BR), and 30 age- and gender-matched non-bicycle riders (NBR). Self-reported function and fear of fall were also assessed. Bicycle riders showed significantly better balance, faster voluntary stepping, and better self-reported advanced lower extremity function compared with NBR. The results might suggest that bicycling regularly preserves balance control and speed of voluntary stepping in older adults because bicycling might maintain specific balance coordination patterns. The results should be treated with caution since BR were older adults who selected an active life style (i.e., bicycling as well as living in an agricultural village) that may bias the results.

Control at stability's edge minimizes energetic costs: expert stick balancing

PubMed Central

Meyer, Ryan; Zhvanetsky, Max; Ridge, Sarah; Insperger, Tamás

2016-01-01

Stick balancing on the fingertip is a complex voluntary motor task that requires the stabilization of an unstable system. For seated expert stick balancers, the time delay is 0.23 s, the shortest stick that can be balanced for 240 s is 0.32 m and there is a ° dead zone for the estimation of the vertical displacement angle in the saggital plane. These observations motivate a switching-type, pendulum–cart model for balance control which uses an internal model to compensate for the time delay by predicting the sensory consequences of the stick's movements. Numerical simulations using the semi-discretization method suggest that the feedback gains are tuned near the edge of stability. For these choices of the feedback gains, the cost function which takes into account the position of the fingertip and the corrective forces is minimized. Thus, expert stick balancers optimize control with a combination of quick manoeuvrability and minimum energy expenditures. PMID:27278361

Element exchange in a water-and gas-closed biological life support system

NASA Astrophysics Data System (ADS)

1997-01-01

Liquid human wastes and household water used for nutrition of wheat made possible to realize 24% closure for the mineral exchange in an experiment with a 2-component version of ``Bios-3'' life support system (LSS) Input-output balances of revealed, that elements (primarily trace elements) within the system. The structural materials (steel, titanium), expanded clay aggregate, and catalytic furnace catalysts. By the end of experiment, the permanent nutrient solution, plants, and the human diet gradually built up Ni, Cr, Al, Fe, V, Zn, Cu, and Mo. Thorough selection and pretreatment of materials can substantially reduce this accumulation. To enhance closure of the mineral exchange involves processing of human- metabolic wastes and inedible biomes inside LSS. An efficient method to oxidize wastes by hydrogen peroxide in a quartz reactor at the temperature of 80°C controlled electromagnetic field is proposed.

Element exchange in a water-and gas-closed biological life support system

NASA Astrophysics Data System (ADS)

Gribovskaya, I. V.; Kudenko, Yu. A.; Gitelson, J. I.

1997-01-01

Liquid human wastes and household water used for nutrition of wheat made possible to realize 24% closure for the mineral exchange in an experiment with a 2-component version of ``Bios-3'' life support system (LSS) Input-output balances of revealed, that elements (primarily trace elements) within the system. The structural materials (steel, titanium), expanded clay aggregate, and catalytic furnace catalysts. By the end of experiment, the permanent nutrient solution, plants, and the human diet gradually built up Ni, Cr, Al, Fe, V, Zn, Cu, and Mo. Thorough selection and pretreatment of materials can substantially reduce this accumulation. To enhance closure of the mineral exchange involves processing of human- metabolic wastes and inedible biomes inside LSS. An efficient method to oxidize wastes by hydrogen peroxide in a quartz reactor at the temperature of 80 degC controlled electromagnetic field is proposed.

Regularity in an environment produces an internal torque pattern for biped balance control.

PubMed

Ito, Satoshi; Kawasaki, Haruhisa

2005-04-01

In this paper, we present a control method for achieving biped static balance under unknown periodic external forces whose periods are only known. In order to maintain static balance adaptively in an uncertain environment, it is essential to have information on the ground reaction forces. However, when the biped is exposed to a steady environment that provides an external force periodically, uncertain factors on the regularity with respect to a steady environment are gradually clarified using learning process, and finally a torque pattern for balancing motion is acquired. Consequently, static balance is maintained without feedback from ground reaction forces and achieved in a feedforward manner.

Experiments in balance with a 2D one-legged hopping machine

NASA Astrophysics Data System (ADS)

Raibert, M. H.; Brown, H. B., Jr.

1984-03-01

The ability to balance is important to the mobility obtained by legged creatures found in nature, and may someday lead to versatile legged vehicles. In order to study the role of balance in legged locomotion and to develop appropriate control strategies, a 2D hopping machine was constructed for experimentation. The machine has one leg on which it hops and runs, making balance a prime consideration. Control of the machine's locomotion was decomposed into three separate parts: a vertical height control part, a horizontal velocity part, and an angular attitude control part. Experiments showed that the three part control scheme, while very simple to implement, was powerful enough to permit the machine to hop in place, to run at a desired rate, to translate from place to place, and to leap over obstacles. Results from modeling and computer simulation of a similar one-legged device are described by Raibert (1983).

Cancer dormancy: from mice to man.

PubMed

Marches, Radu; Scheuermann, Richard; Uhr, Jonathan

2006-08-01

In this review, we focused on our studies of cancer dormancy in a murine B cell lymphoma and human breast cancer. Lifelong dormancy was induced in syngeneic mice by prior immunization to the idiotype of the tumor cell (TC) Ig before TC challenge. The mice maintained approximately 10(6) lymphoma cells in their spleen throughout their lifetime despite replication of the TCs at a reduced rate. Recurrences occurred randomly. Because of the balance between replication and cell death, we hypothesized that a similar balance might occur in long-term survivors of breast cancer when the risk of recurrences is very low. We developed a sensitive assay for circulating tumor cells (CTCs) which none were found in normal age-matched women. One third of patients, 7-22 years after mastectomy and without any evidence of disease, had CTCs. The half-life of these CTCs could be deduced from other studies as probably 2-3 hours. Hence, there was a precise balance between replication of TCs (presumably from micrometastases) and cell death. Therefore, a major population of clinically cured breast cancer patients have a chronic disease controlled by their own physiological mechanisms. We speculate on underlying mechanisms based both on studies in experimental models and clinical trials.

[The significance of sympathovagal balance in the forming of respiration-dependent oscillations in cardiovascular system in human].

PubMed

Krasnikov, G V; Tiurina, M Ĭ; Tankanag, A V; Piskunova, G M; Cheremis, N K

2014-01-01

The effect of deep breathing controlled in both rate and amplitude on the heart rate variability (HRV) and respiration-dependent blood flow oscillations of forearm and finger-pad skin has been studied in 29 young healthy volunteers from 18 to 25 years old. To reveal the effect of the segments of the vegetative autonomic nervous system on the amplitudes of HRV and respiration-dependent oscillations of skin blood flow we estimated the parameters of the cardiovascular system into two groups of participants: with formally high and low sympathovagal balance values. The sympathovagal balance value was judged by the magnitude of LF/HF power ratio calculated for each participant using the spontaneous breathing rhythmogram. It was found what the participants with predominant parasympathetic tonus had statistically significant higher amplitudes of H R V and skin blood flow oscillations in the breathing rate less than 4 cycles per min than the subjects with predominant sympathetic tonus. In the forearm skin, where the density of sympathetic innervations is low comparatively to that in the finger skin, no statistically significant differences in the amplitude of respiratory skin blood flow oscillations was found between the two groups of participants.

The internal representation of head orientation differs for conscious perception and balance control.

PubMed

Dalton, Brian H; Rasman, Brandon G; Inglis, J Timothy; Blouin, Jean-Sébastien

2017-04-15

We tested perceived head-on-feet orientation and the direction of vestibular-evoked balance responses in passively and actively held head-turned postures. The direction of vestibular-evoked balance responses was not aligned with perceived head-on-feet orientation while maintaining prolonged passively held head-turned postures. Furthermore, static visual cues of head-on-feet orientation did not update the estimate of head posture for the balance controller. A prolonged actively held head-turned posture did not elicit a rotation in the direction of the vestibular-evoked balance response despite a significant rotation in perceived angular head posture. It is proposed that conscious perception of head posture and the transformation of vestibular signals for standing balance relying on this head posture are not dependent on the same internal representation. Rather, the balance system may operate under its own sensorimotor principles, which are partly independent from perception. Vestibular signals used for balance control must be integrated with other sensorimotor cues to allow transformation of descending signals according to an internal representation of body configuration. We explored two alternative models of sensorimotor integration that propose (1) a single internal representation of head-on-feet orientation is responsible for perceived postural orientation and standing balance or (2) conscious perception and balance control are driven by separate internal representations. During three experiments, participants stood quietly while passively or actively maintaining a prolonged head-turned posture (>10 min). Throughout the trials, participants intermittently reported their perceived head angular position, and subsequently electrical vestibular stimuli were delivered to elicit whole-body balance responses. Visual recalibration of head-on-feet posture was used to determine whether static visual cues are used to update the internal representation of body configuration for perceived orientation and standing balance. All three experiments involved situations in which the vestibular-evoked balance response was not orthogonal to perceived head-on-feet orientation, regardless of the visual information provided. For prolonged head-turned postures, balance responses consistent with actual head-on-feet posture occurred only during the active condition. Our results indicate that conscious perception of head-on-feet posture and vestibular control of balance do not rely on the same internal representation, but instead treat sensorimotor cues in parallel and may arrive at different conclusions regarding head-on-feet posture. The balance system appears to bypass static visual cues of postural orientation and mainly use other sensorimotor signals of head-on-feet position to transform vestibular signals of head motion, a mechanism appropriate for most daily activities. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Differential Sensitivity Between a Virtual Reality Balance Module and Clinically Used Concussion Balance Modalities.

PubMed

Teel, Elizabeth F; Gay, Michael R; Arnett, Peter A; Slobounov, Semyon M

2016-03-01

Balance assessments are part of the recommended clinical concussion evaluation, along with computerized neuropsychological testing and self-reported symptoms checklists. New technology has allowed for the creation of virtual reality (VR) balance assessments to be used in concussion care, but there is little information on the sensitivity and specificity of these evaluations. The purpose of this study is to establish the sensitivity and specificity of a VR balance module for detecting lingering balance deficits clinical concussion care. Retrospective case-control study. Institutional research laboratory. Normal controls (n = 94) and concussed participants (n = 27). All participants completed a VR balance assessment paradigm. Concussed participants were diagnosed by a Certified Athletic Trainer or physician (with 48 hours postinjury) and tested in the laboratory between 7 and 10 days postinjury. Receiver operating characteristic curves were performed to establish the VR module's sensitivity and specificity for detecting lingering balance deficits. Final balance score. For the VR balance module, a cutoff score of 8.25 was established to maximize sensitivity at 85.7% and specificity at 87.8%. The VR balance module has high sensitivity and specificity for detecting subacute balance deficits after concussive injury. The VR balance has a high subacute sensitivity and specificity as a stand-alone balance assessment tool and may detect ongoing balance deficits not readily detectable by the Balance Error Scoring System or Sensory Organization Test. Virtual reality balance modules may be a beneficial addition to the current clinical concussion diagnostic battery.

Modelling accidental hypothermia effects on a human body under different pathophysiological conditions.

PubMed

Coccarelli, Alberto; Boileau, Etienne; Parthimos, Dimitris; Nithiarasu, Perumal

2017-12-01

Accidental exposure to cold water environment is one of the most challenging situations in which hypothermia occurs. In the present work, we aim to characterise the energy balance of a human body subjected to such extreme environmental conditions. This study is carried out using a recently developed computational model and by setting boundary conditions needed to simulate the effect of cold surrounding environment. A major finding is the capacity of the body core regions to maintain their temperature high for a substantial amount of time, even under the most extreme environmental conditions. We also considered two disease states that highlight the spectrum of possible pathologies implicated in thermal regulation of the human body. These states are (i) cardiomyopathy, which affects the operating capacity of the heart, and (ii) malnutrition, which directly impairs the body's ability to regulate heat exchange with the environment. We have found that cardiomyopathy has little influence on the thermal balance of the human body, whereas malnutrition has a profound negative effect on the thermal balance and leads to dramatic reduction in core temperature.

Assisting People with Multiple Disabilities Actively Correct Abnormal Standing Posture with a Nintendo Wii Balance Board through Controlling Environmental Stimulation

ERIC Educational Resources Information Center

Shih, Ching-Hsiang; Shih, Ching-Tien; Chu, Chiung-Ling

2010-01-01

The latest researches adopted software technology turning the Nintendo Wii Balance Board into a high performance change of standing posture (CSP) detector, and assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture). This study extends Wii Balance Board…

Active model-based balancing strategy for self-reconfigurable batteries

NASA Astrophysics Data System (ADS)

Bouchhima, Nejmeddine; Schnierle, Marc; Schulte, Sascha; Birke, Kai Peter

2016-08-01

This paper describes a novel balancing strategy for self-reconfigurable batteries where the discharge and charge rates of each cell can be controlled. While much effort has been focused on improving the hardware architecture of self-reconfigurable batteries, energy equalization algorithms have not been systematically optimized in terms of maximizing the efficiency of the balancing system. Our approach includes aspects of such optimization theory. We develop a balancing strategy for optimal control of the discharge rate of battery cells. We first formulate the cell balancing as a nonlinear optimal control problem, which is modeled afterward as a network program. Using dynamic programming techniques and MATLAB's vectorization feature, we solve the optimal control problem by generating the optimal battery operation policy for a given drive cycle. The simulation results show that the proposed strategy efficiently balances the cells over the life of the battery, an obvious advantage that is absent in the other conventional approaches. Our algorithm is shown to be robust when tested against different influencing parameters varying over wide spectrum on different drive cycles. Furthermore, due to the little computation time and the proved low sensitivity to the inaccurate power predictions, our strategy can be integrated in a real-time system.

A pilot study on the influence of exercising on unstable training machine on balance control and trunk muscles activity.

PubMed

Domeika, Aurelijus; Aleknaite-Dambrauskiene, Ieva; Poskaitis, Vytautas; Zaveckas, Vidmantas; Grigas, Vytautas; Zvironiene, Ausra

2018-05-16

The main position of the working population is becoming sitting. Immobile prolonged sedentary time may cause negative effects including reduced intervertebral discs nutrition. Main ways of mitigating them are regular position changes and exercising. To evaluate influence of the short term training on unstable training machine on balance control and trunk muscles activity in patients with lower back pain. Participants (n=16) experiencing lower back pain were trained on an unstable sculling machine "Rehabili". Their balance tested by (Biodex Balance System) and rectus abdominis, externus oblique, transverse abdominis, multifidus and erector spine muscles activity (measured by surface electromyography) while sitting and standing with usual and aligned body postures both before and after six weeks of training (three 15 minutes sessions per week) were compared in between. Balance control improved after the training program. Besides, more symmetrical activation of both sides rectus and transversus abdominis muscles, as well as increased transversus abdominis muscle activation of 19% (p< 0.05), were observed. Six weeks short sessions training on unstable training machine improved balance control and increased trunk muscles activity especially in aligned body posture when standing or sitting on unstable surface.

Investigation of human-robot interface performance in household environments

NASA Astrophysics Data System (ADS)

Cremer, Sven; Mirza, Fahad; Tuladhar, Yathartha; Alonzo, Rommel; Hingeley, Anthony; Popa, Dan O.

2016-05-01

Today, assistive robots are being introduced into human environments at an increasing rate. Human environments are highly cluttered and dynamic, making it difficult to foresee all necessary capabilities and pre-program all desirable future skills of the robot. One approach to increase robot performance is semi-autonomous operation, allowing users to intervene and guide the robot through difficult tasks. To this end, robots need intuitive Human-Machine Interfaces (HMIs) that support fine motion control without overwhelming the operator. In this study we evaluate the performance of several interfaces that balance autonomy and teleoperation of a mobile manipulator for accomplishing several household tasks. Our proposed HMI framework includes teleoperation devices such as a tablet, as well as physical interfaces in the form of piezoresistive pressure sensor arrays. Mobile manipulation experiments were performed with a sensorized KUKA youBot, an omnidirectional platform with a 5 degrees of freedom (DOF) arm. The pick and place tasks involved navigation and manipulation of objects in household environments. Performance metrics included time for task completion and position accuracy.