Postural regulation of teenagers performing pop dance, according to stabilometry data

Knowledge of postural regulation in different sports is useful for sports selection and for improvement of postural stereotypes.Objective: to reveal postural regulation features of teenagers involved in pop dance.Materials and methods: 15 pop dancers involved in dance more than 10 years performed Romberg and optokinetic tests on computer stabilograph “Trust-M Stabilo”.Results: the area and length of the dancers’ statokinesiogram were less than in general sample, statokinesiogram’s pressure center had been dextrally dislocated. Visual disturbances as well as vision deprivation led to statistically significant increase in speed of center of pressure movement along reference plane and in the ratio of statokinesiogram’s length to its area. All these changes were less pronounced than in the general sample.Conclusions: postural regulation of dancers proved to be better than that of healthy people who were not involved in sports.

Evaluation of vestibular function in children with purulent media otitis by computer stabilometry

The aim of the research – assessment of vestibular function in children with acute purulent otitis media by computer static stabilometry compared with typically developed children of the same age. Materials and methods: 22 children with purulent otitis media aged 4 to 7 years and 30 practically healthy peers were examined by static stabilometry on the device “MPFI stabilograph 1” (Kharkiv, Ukraine). Indicators of variation and shape of the pressure center distribution, spectral-correlation indicators of stabilograms, as well as integral indicators of stability (length, velocity and angle of postural oscillations) were taken into account and the equilibrium functions of the two sensory states (open and closed eyes) are calculated in the StabiliS software. Results: purulent otitis media causes posterior displacement of the absolute coordinates of the pressure center. In the state with closed eyes, children with purulent otitis differ from their healthy coevals by 14 of 24 stabilometric parameters, including stabilogram length, speed, angle and amplitude of oscillations, giving way to them in the stability of equilibrium. Children with purulent otitis media are more sensitive to the visual canal of postural control than their coevals. Involvement of visual afferents in postural control significantly improves balance maintenance in children with purulent otitis by reducing deviations of postural oscillations, which is reflected in the probable changes of 9 out of 24 stabilometric parameters compared to control. Conclusions: In preschool age, purulent otitis media leads to latent vestibular dysfunction, which is manifested by a violation of the stability of the vertical posture in a state with closed eyes and is compensated by visual-vestibulo-proprioceptive integration in the process of postural control.

Theoretical study into the aerodynamic imbalance of a propeller blade and the correcting masses to balance it

This paper reports the theoretically investigated aerodynamic imbalance of the propeller blade, as well as correcting masses for balancing it. It has been established that the aerodynamic forces acting on the propeller blade can be balanced by the adjustment of masses. This is also true for the case of compressed air (gas) provided that the blades are streamlined by laminar flow. That makes it possible to use rotor balancing methods to study the aerodynamic forces acting on the propeller blade. The rotating blade mainly generates torque aerodynamic imbalance due to a lift force. A much smaller static component of the aerodynamic imbalance is formed by the drag force acting on the blade. The correcting mass located in the propeller plane balances both static and torque components of the aerodynamic imbalance in its correction plane. A second correcting mass (for example, on the electric motor shank) balances the torque component of aerodynamic imbalance in its correction plane. The calculations are simplified under the assumption that the equilibrium of aerodynamic forces is perpendicular to the chord of the blade. For approximate calculations, one can use information about the approximate location of the pressure center. The aerodynamic forces acting on the blade can be determined on the basis of the correcting masses that balance them. The accuracy in determining the aerodynamic forces could be improved by measuring a lift force. The computational experiment has confirmed the theoretical results formulated above. The experiment further proves the possibility of applying the devised theory for propellers whose rotation speed changes with a change in the angles of blade installation. The findings reported here could be used both for devising methods of propeller balancing and for constructing methods to study the aerodynamic forces acting on the blade.

Analysis of the Influence of Age Stages on Static Plantar Pressure Indicators for Karate Do Practitioners (Preliminary Report)

The investigation aims at static examination and determination of differences for three age groups: under 13, 13–15 years old and over 15, all practitioners of the martial art karate do. This investigation occured at the level of the main parameters, measured using the FreeMed baropodometric platform and Free Step software by Sensor Medica: plantar surface areas, location of the pressure center (C) inside the support polygon, imbalances noticed at the level of the plantar areas, Pmax value, weight distribution on each foot and at the level of the rearfoot and forefoot areas, misalignments of the pressure centers of each foot, etc. Results: subjects under the age of 13 had the highest number of cases related to the off-centered positioning of the pressure center (C); the groups of those under 13 and over 15 years old located in most cases Pmax at the level of the left retropodal part, and those between 13–15 years old have a location on the dominant leg, at the level of the right retropodal part. The highest numbers of cases of normal bilateral leg are for the group under 13 years, and the other groups have a higher incidence of various plantar imbalances. The analysis of variance (F) identified only two situations in which the independent variable, “age stages,” significantly influences the resulting parameters, at the level of the non-dominant foot: forefoot_left_surface and total_left_surface. The data differences for the right/left pairs within each batch generate insignificant values of |Z| for most cases, with the superiority of the dominant foot parameters for the first two age groups, but in the case of the group over 15 years old, some results are atypical, with higher average values of left/non-dominant foot parameters in the following cases: total_left_Pmax, total_left_Pavg, rearfoot_left_load_percent, rearfoot_left_weight_ratio_percent. The comparison between the data pairs for all three batches (between the forefoot and rearfoot plantar areas) generated significant values of |Z| only for the area of the plantar surfaces. The older the subjects, the more obvious the plantar load on the forefoot area, which is similar to the results of some martial arts studies analyzed here, and is determined by the long use of the non-dominant foot as a support base, during kicks with the dominant one.

Impacts of Late-Spring North Eurasian Soil Moisture Variation on Summer Rainfall Anomalies in Northern East Asia

This paper reports findings from a diagnostic and modeling analysis that investigates the impact of the late-spring soil moisture anomaly over North Eurasia on the boreal summer rainfall over northern East Asia (NEA). Soil moisture in May in the region from the Kara-Laptev Sea coasts to Central Siberian Plateau is found to be negatively correlated with the summer rainfall from Mongolia to Northeast China. The atmospheric circulation anomalies associated with the anomalously dry soil are characterized by a pressure dipole with the high-pressure center located over North Eurasia and the low-pressure center over NEA, where an anomalous lower-level moisture convergence occurs, favoring rainfall formation. Diagnoses and Modeling experiments demonstrate that the effect of the spring low soil moisture over North Eurasia may persist into the following summer through modulating local surface latent and sensible heat fluxes, increasing low-level air temperature at higher latitudes, and effectively reducing the meridional temperature gradient. The weakened temperature gradient could induce the decreased zonal wind and the generation of a low-pressure center over NEA, associated with a favorable condition of local synoptic activity. The above relationships and mechanisms are vice versa for the prior wetter soil and decreased NEA rainfall. These findings suggest that soil moisture anomalies over North Eurasia may act as a new precursor providing an additional predictability source for better predicting the summer rainfall in NEA.

Reliability and Repeatability of Pressure Center Analysis with Low-Dye Taping Using Force Platform Podiatry Sensors in Feet with Excessive Pronation

Background: The analysis of the center of pressure (COP) is a method used to assess the foot function, but its reliability and repeatability have not been evaluated. COP can be altered by diverse conditions, like an excessive foot pronation. Low-Dye taping is commonly used for the treatment of symptoms related to an excessive pronation. To date, no study has evaluated the effects of the Low-Dye taping on COP and the duration of its effects. Thus, the main purpose of this manuscript was to assess the reliability and repeatability of the percentage of center of pressure locus area (%CLA) in feet with an excessive pronation, and secondarily, to assess that the Low-Dye taping modifies the %CLA during the immediate 48 h. Methods: An observational study of the reliability and repeatability of the %CLA variable with the Low-Dye taping in feet with excessive pronation was carried out. We used the EPS-Platform to evaluate the results of the variable in 6 conditions in a first session to evaluate the reliability of the results. We compared the results of the first session with the results in a second session to evaluate the repeatability of the results. We also carried out an ANOVA test to evaluate the changes that the taping produced in the variable between without taping with the rest of the 6 conditions. Results: For the %CLA, we observed a reliability greater than 0.80, measured by the interclass ratio index, both in the first session before taping, and in the second session before taping, thus being a repeatability variable. In the following times, with taping, at 10 min with tape, at 20 min with tape, at 24 h with tape and at 48 h with tape; an interclass ratio coefficient (ICC) higher than 0.80 was again obtained, thus being a reliable variable in all measurements made. The Low-Dye taping did not change %CLA from the time the tape was put in until 48 h (p-value = 1.000). Conclusions: The %CLA variable, in feet with excessive pronation, proved to be a reliable variable in all the measurements obtained before putting on the tape and during the following 48 h with the tape, and a repeatable variable. The Low-Dye taping did not change the %CLA from the time the tape was put in until 48 h.

The impacts of Seroja Tropical Cyclone towards extreme weather in East Nusa Tenggara

This paper aims to discuss the Seroja Tropical Cyclone and its impact on extreme weather. Seroja tropical cyclones occur from April 4 to 5th 2021, in the East Nusa Tenggara (NTT) region. Based on data from the Meteorology, Climatology and Geophysics Agency (BMKG), the initial position of the Seroja tropical cyclone was in the Savu Sea, southwest of Timor Island. Since April 1, 2021, the NTT region has become the center of low pressure that triggers the formation of this cyclone. When a tropical storm occurs, the intensity of rainfall which initially reaches less than 60 mm/day, increases rapidly to more than 100 mm/day on April 4 to 5, 2021. This is the impact of the low-pressure center that triggers the formation of tropical cyclones in the region.

Efeitos da Kinesiotaping na Aplicação em Tornozelos Sobre o Controle Postural de Indivíduos Saudáveis

Este estudo avaliou o efeito da aplicação da Kinesiotape no controle postural de indivíduos jovens saudáveis. Quarenta participantes foram divididos em dois grupos: G1 (n = 20) composto por homens com idade de 23 ± 2,12 anos e o G2 (n = 20) por mulheres com idade 24 ± 4,96 anos. Ambos os grupos receberam a aplicação da Kinesiotape na região dos tornozelos e foram submetidos à avaliação do controle postural em apoio unipodal direito (UNPD) e esquerdo (UNPE) na plataforma de força em quatro momentos: pré-intervenção (PRE), imediatamente após (IME), 24 horas (24H) e 48 horas (48H) após a aplicação da kinesio. A análise estatística foi realizada através do teste de Friedman, utilizando o software IBM SPSS Statistics versão 24. A análise das variáveis do centro de pressão mostrou uma redução significativa no G1 na VEL ML na posição UNPD entre os períodos PRE e IME (p = 0,013) e na FAP na posição UNPD em todos os períodos (PRE-IME p = 0,042; PRE-24H p = 0,02; PRE-48h p = 0,007). No G2 houve diferença na VEL AP na posição UNPD (PRE-48H p = 0,002) e na UNPE em todos os períodos (PRE-IME p = 0,009; PRE-24H p = 0,029; PRE-48h p = 0,001), e na VEL ML na posição UNPE (PRE-48H p = 0,016), evidenciando que a aplicação da Kinesiotape na região de tornozelos, melhora a estabilidade no controle postural em homens e mulheres saudáveis. Palavras-chave: Kinesio Tape. Controle Postural. Propriocepção. Plataforma de Força. Abstract This study evaluated the effect of Kinesiotape application on postural control in healthy young individuals. Forty participants were divided into two groups: G1 (n = 20) composed of men aged 23 ± 2.12 years and G2 (n = 20) women aged 24 ± 4.96 years. Both groups received the Kinesiotape application at the ankles and underwent postural control assessment in right (UNPD) and left (UNPE) unipedal stance on the force platform in four moments: pre-intervention (PRE), immediately after ( IME), 24 hours (24H) and 48 hours (48H) after kinesiotape application. Statistical analysis was performed using the Friedman test, using the IBM SPSS Statistics version 24 software. The analysis of the pressure center variables showed a significant reduction in G1 in the ML VEL in the UNPD position between the PRE and IME periods (p = 0.013 ) and FAP in the UNPD position in all periods (PRE-IME p = 0.042; PRE-24H p = 0.02; PRE-48h p = 0.007). There was a difference in the G2 AP VEL in the UNPD position (PRE-48H p = 0.002) and in UNPE in all periods (PRE-IME p = 0.009; PRE-24H p = 0.029; PRE-48h p = 0.001), and in ML SPE in the UNPE position (PRE-48H p = 0.016), showing that the Kinesiotape application at the ankles, improves stability in postural control in healthy men and women. Keywords: Kinesiotape. Postural Control. Proprioception. Force Platform.