Postural control and risk of falling in people who are blind: The effect and durability of perturbation and vestibular exercises

The aim of this study was to compare the effect and durability of perturbation and vestibular exercises on balance and the risk of falling in people with visual impairment (VI). Thirty-six men with VI were divided into three groups, including a control and two experimental (perturbation and vestibular) groups. The experimental groups performed perturbation and vestibular exercises for 4 weeks and three sessions per week. Biodex balance system was used to assess balance and falling risk before and after training interventions. To evaluate the effects within and between groups at three levels of measurement: pre-test, post-test, and durability effect between three groups, repeated measures analysis of variance (ANOVA) and one-way ANOVA were used. Repeated measures ANOVA test showed that both experimental groups showed significant improvements in static balance, dynamic balance, and falling risk. In comparison between the groups, the results showed that in the post-test and durability stages, there was a significant difference between the groups and the perturbation exercise group had a greater effect on the dependent variables. Due to the effectiveness of exercises, it is recommended that people with VI pay attention to balance-based perturbation exercises to strengthen the somatosensory system and vestibular exercises to strengthen the vestibular system.

The effects of ankle Kinesiotaping on postural control in healthy taekwondo athletes

Background and Study Aim. Although Kinesiotape is widely used by athletes, information about its effect is unclear. Its effect on postural control might directly affect an athlete's performance. In this study, it is aimed to find out whether ankle Kinesiotaping in taekwondo athletes affects postural control. Material and Methods. Twenty-four healthy university students – taekwondo athletes (12 females, 12 males) were included in the study voluntarily (Age 21.00 ± 1.53 years; height 173.33 ± 7.29 cm; body weight 63.41 ± 9.41 kg). Kinesiotape was carried out to the dominant ankle of the participants. Kinesiotape was applied supportively to peroneus longus, peroneus brevis, and tibiofibular ligament. All participants were taken to postural control measurements twice with Kinesiotape (KT) and without KT. Postural control was measured using the Biodex Balance System with eyes open (EO) and eyes closed (EC). Overall Stability Index (OSI), anterior-posterior sway (AP) and medio-lateral sway (ML) scores were used in the evaluation of postural control. Wilcoxon test was used to compare balance scores under EO condition, and the t-test was used for dependent groups to compare balance scores under EC condition. Results. In EO condition, no significant difference was found between OSI, AP, and ML scores of the taekwondo athletes with KT and without KT (p > 0.05). In EC condition, no significant difference was found between OSI, AP, and ML scores of male taekwondo athletes with KT and without KT (p > 0.05). It was found that Kinesiotape in EC condition decreased OSI and AP sway scores in female taekwondo athletes (p < 0.05). Conclusions. It was determined that ankle Kinesiotaping of taekwondo athletes did not change the postural balance in EO condition. In EC condition it did not change the postural sway of male taekwondo athletes, but it improved the postural control performances of female taekwondo athletes.

Association of blood pressure and postural control in older adults with hypertension: an observational study

The study investigated the association of orthostatic hypotension (OH) with functional position change and balance in older adults with hypertension. The presence of OH was assessed with intermittent (OH intermittent) and continuous blood pressure (OH continuous) monitoring. The change in functional position was tested with sitting to standing assessment, balance performance using activity specific balance confidence scale (ABC), and timed up and go test (TUG). Testing unilateral and bilateral standing with and without altered sensory inputs was tested using the Humac balance system. ABC, TUG, and standing up time showed no significant association with OH intermittent and OH continuous. A significant association was found between bilateral standing with eyes closed on foam surface for overall stability index and OH intermittent. Older people with hypertension may be routinely examined for OH and appropriate intervention strategies should be included for comprehensive care.

System modeling and control system performance optimization of magnetic suspension and balance system

A magnetic suspension and balance system (MSBS) is a kind of aerodynamic test equipment for aircraft. It uses levitation control technology to replace the mechanical support and strain measurement technology in traditional wind tunnel balance. It has the advantage of no model support to interfere with the wind tunnel flow field and make the test environment more realistic, but the MSBS has technical difficulties to be solved. It is difficult to control and stabilize because it has a large suspension gap, nonlinear magnetic field, a long-acting distance of magnetic force, and uses a visual sensor to feedback the position of the controlled object that it has signal noise. At present, there are few studies on the suspension control method and suspension performance of MSBS. In this paper, in order to solve the above technical difficulties, the vertical control of the MSBS is taken as the research object, the electromagnetic field of the vertical coil is modeled and analyzed. A new control algorithm based on a fast-tracking differentiator (FTD) is proposed to solve the signal noise problem in MSBS. The influence of various factors in the control link on the suspension system is analyzed, and its optimization is carried out to improve the performance of the suspension system.

Photon Force MEMS cantilever combined with fibre optic system as a measurement technique for optomechanical studies

In this paper we present a metrological measurement technique that is a combination of fibre optic interferometry and a microelectromechanical system (MEMS) sensor for photon force (PF) measurement with traceability via an electromagnetic way. The main advantage of the presented method is the reference to the current balance, which is the primary mass/force metrological standard. The MEMS cantilever is a transducer of the photon force to the deflection that can be compensated with the use of the Lorentz force. This movement is measured with the use of the interferometer and does not require any mechanical calibration. Combining the MEMS current balance system with the interferometry is then the unique and fully metrological solution. The resolution of the proposed measurement technique is calculated to be 4 pN//Hz^(0.5) (2% uncertainty). The PF–MEMS used for the investigation is the cantilever with the resolution of 46 fN/Hz0.5, which was calculated from the thermomechanical noise, and is far below the whole system resolution limit. As far as the whole construction is based on the fibre optic system, it does not require any complex adjustment procedure and may work as an optomechanical reference in any metrological laboratory.

Design of Robust Control System of Magnetic Suspension and Balance System through Harmonic Excitation Simulation

The magnetic suspension and balance system (MSBS) uses magnetic force and moment to precisely control the movement of the test object located at the center of the test section without mechanical contact, and at the same time measure the external force acting on the test object. If such an MSBS is installed around the test section of the wind tunnel so that the position and attitude angle of the test object follow the harmonic function, various vibration tests can be performed on structures subjected to aerodynamic loads without the influence of the mechanical support. Because the control force and moment in the MSBS is generated by a number of electromagnets located around the test section, it is necessary to apply the adaptive control algorithm to the position and attitude control system so that the experiment can be carried out stably despite the sudden performance change of each electromagnet and electric power supply. In this study, a fault-tolerant position and attitude angle control system was designed through an adaptive control algorithm, and the effectiveness was verified through simulation under the condition that the electric power supply of MSBS failed.

Methods and Strategies for Reconditioning Motor Output and Postural Balance in Frail Older Subjects Prone to Falls

In frail older subjects, the motor output of the antigravity muscles is fundamental in resisting falls. These muscles undergo accelerated involutions when they are inactive and the risk of falling increases during leisure and domestic physical activity. In order to reduce their risk of falling, frail older subjects limit their physical activities/exercises. The problem is that the less they exercise, the less they are able to exercise and the greater the risk in exercising. Hence, a vicious circle sets up and the antigravity muscles inevitably continue to deteriorate. This vicious circle must be broken by starting a reconditioning program based on developing the strength of antigravity muscles (especially lower-limb muscles). To begin with, for each increase in muscle strength, postural balance is improved. Once this increase reaches the threshold beyond which postural balance no longer improves, it seems appropriate to implement exercises aimed at concomitantly improving motor output and postural balance in order to counteract or even reverse the involution process of the postural balance system. Methods and strategies toward this end are proposed in this present communication. However, the transfer effects between strength increase and postural balance ability are not yet totally known and future research should evaluate the relationship between muscle strength and postural balance throughout rehabilitation programs (i.e., program follow-ups) in frail older subjects in order to advance knowledge of this relationship.

Molecularly Imprinted Chitosan-Based Thin Films with Selectivity for Nicotine Derivatives for Application as a Bio-Sensor and Filter

This study reports the feasible use of chitosan as a thin film biosensor on the very sensitive quartz crystal micro balance system for detection of blends of multiple templates within a single matrix. The development of chitosan-based thin film materials with selectivity for nicotine derivatives is described. The molecular imprinting of a combination of nicotine derivatives in N-diacryloyl pipiradine-chitosan-methacrylic acid copolymer films on quartz crystal resonators was used to generate thin films with selectivity for nicotine and a range of nicotine analogues, particularly 3-phenylpyridine. The polymers were characterized by spectroscopic and microscopic evaluations; surface area, pore size, pore volume using Breuner-Emmet-Teller method. Temperature characteristics were also studied. The swelling and structure consistency of the Chitosan was achieved by grafting with methylmethacrylic acid and cross-linking with N-diacrylol pipiradine. A blend of 0.002 g (0.04 mmol) of Chitosan, 8.5 μL Methylmethacrylic Acid and 1.0 mg N-diacrylol pipradine (BAP) presented the best blend formulation. Detections were made within a time interval of 99 sec, and blend templates were detected at a concentration of 0.5 mM from the Quartz crystal microbalance resonator analysis. The successful crosslinking of the biopolymers ensured successful control of the swelling and agglomeration of the chitosan, giving it the utility potential for use as thin film sensor. This successful crosslinking also created successful dual multiple templating on the chitosan matrix, even for aerosolized templates. The products can be used in environments with temperature ranges between 60 °C and 250 °C.

Vertigo in Systemic Lupus Erythematosus: A Case Report

Introduction: Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with multiorgan involvement based on an autoimmune process. SLE, although rare, is associated with comorbid vertigo. Vertigo in SLE is caused by a disturbance in the balance system in the inner ear. Few journals discuss SLE related to vertigo. We will report a case SLE with complaints of recurrent vertigo. Case: A-37-year-old woman came with complaints of recurrent vertigo since 1 day ago with a duration of about 15 minutes associated with nausea, vomiting and nystagmus. Patient did not complain tinnitus or hearing disorders. The patient has been diagnosed as SLE since two years ago. The physical examination showed normal and Neuro-otological examination revealed nystagmus horizontal unidirectional, negative skew deviation test, positive Head Impulse Test (HIT). Conclusion: Patients with a diagnosis of SLE can find comorbid peripheral vestibular disorders such as vertigo where there is an antibody mechanism that can damage the inner ear. Treatment of audiovestibular symptoms is usually strongly associated with systemic conditions and in patients with vertigo used betahistine to treatment. Keywords: SLE, Inner Ear, Vertigo.