Relación entre adiposidad corporal y fuerza de prensión manual con la preocupación por la alimentación en deportistas universitarios / Relationship between body adiposity and handgrip strength with dietaryconcerns in university athletes

Introducción: La composición corporal es clave para tener un adecuado estado de salud y aptitud física. Así también, la fuerza muscular es usada como un predictor importante del rendimiento deportivo. Objetivo: Relacionar la adiposidad corporal y la fuerza de prensión manual con la preocupación por la alimentación en deportistas universitarios. Metodología: Se efectuó un estudio de tipo descriptivo (comparativo-correlacional) en 130 deportistas universitarios de una universidad de Chile (90 hombres y 40 mujeres). El rango de edad osciló entre los 18 y 28 años. Se evaluó las medidas antropométricas: peso, estatura, 5 pliegues cutáneos (bicipital, tricipital, subescapular, suprailíaco y abdominal), la fuerza de prensión manual (FPM) y se aplicó la escala de preocupación por la alimentación. Se calculó el % de grasa corporal, el Índice de masa corporal (IMC). Resultados: La escala de preocupación por la alimentación se relacionó negativamente con los indicadores de adiposidad corporal (r= -0,16 a -0,33; p<0,05), mientras tanto, las correlaciones de la FPM (derecha e izquierda) con la escala de preocupación por la alimentación fueron positivas (r= 0,20 a 0,24; p<0.05). Los hombres categorizados con alta y moderada preocupación por la alimentación presentaron mejores niveles de adiposidad y mayor FPM en la mano derecha (p<0,05), mientras que las mujeres, únicamente las categorizadas con alto nivel de preocupación presentaron bajos niveles de adiposidad y mejor FPM en ambos manos (p<0,05). Conclusión: Los jóvenes que presentan mayor preocupación por la alimentación evidenciaron menor nivel de adiposidad corporal y un mejor desempeño en la FPM que sus contrapartes con menor preocupación. Estos resultados sugieren promover charlas en relación al consumo de alimentos, dado que puede ser una excelente alternativa para sensibilizar a los jóvenes en el cuidado de su adiposidad corporal y la fuerza isométrica.(AU)

Introduction: Body composition is key to having an ade-quate state of health and fitness. Also, muscle strength isused as an important predictor of sports performance.Objective: To relate body adiposity and hand grip strengthto nutritional concerns in university athletes. Methodology: A descriptive study (comparative-correla-tional) was carried out in 130 university athletes from a uni-versity in Chile (90 men and 40 women). The age range wasbetween 18 and 28 years. Anthropometric measurementswere evaluated: weight, height, 5 skinfolds (bicipital, tricipi-tal, subscapular, suprailiac and abdominal), manual gripstrength (MPF) and the food concern scale was applied. Bodyfat %, body mass index (BMI) were calculated.Results: The food preoccupation scale was negatively re-lated to body adiposity indicators (r= -0.16 to -0.33; p<0.05),while the correlations of FPM (right and left) with the foodpreoccupation scale were positive (r= 0.20 to 0.24; p<0.05).Males categorized with high and moderate concern about ea-ting presented better levels of adiposity and higher FPM in theright hand (p<0.05), while females, only those categorizedwith high level of concern presented low levels of adiposityand better FPM in both hands (p<0.05).Conclusion: Young people with a higher level of concernabout food showed lower levels of body adiposity and betterperformance in FPM than their counterparts with lower levelsof concern. These results suggest promoting talks regardingfood consumption, since it can be an excellent alternative tosensitize young people to take care of their body adiposityand isometric strength.(AU)

Body surface area is a predictor of maturity status in school children and adolescents.

BACKGROUND: Generally, Body surface area (BSA) changes significantly during growth and maturation. These increases portend a possible relationship between body size as determined by BSA with maturational status in children and adolescents. OBJECTIVE: To determine the relationship between maturity status (MS) obtained by non-invasive anthropometric methods and body surface area (BSA) in children and adolescents of both sexes in a regional population of Chile. Additionally, we sought to verify the type of linear or nonlinear relationship between MS and BSA in both sexes. METHODS: A descriptive (cross-sectional) study was designed in 950 children and adolescents of both sexes (539 males and 411 females). The age range ranged from 6.0 to 17.9 years. Anthropometric measurements were evaluated: body weight, standing height, sitting height. MS was assessed by means of two non-invasive anthropometric techniques. Both techniques predict peak years of growth velocity (APHV) through a regression equation for each sex. BSA (m2) was estimated by means of the Haycock equation. RESULTS: The R2 in the linear model is relatively lower (R2 = 0.80 to 0.89 in males and 0.74 to 0.66 in females) in relation to the nonlinear quadratic model (R2 = 0.81 in males and 0.76 to 0.69). The quadratic nonlinear quadratic model reflected an adequate fit (RMSE) for the data set, being in men (RMSE = 1.080 and 1.125), while in women (RMSE = 1.779 and 1.479). CONCLUSION: BSA is positively associated with MS determined by two non-invasive methods in Chilean children and adolescents: The nonlinear quadratic model was a better fit to the data distribution. The results suggest the use of BSA as a possible predictor of maturity status in Chilean youth.

Aptitud física en jóvenes futbolistas y no-futbolistas por edadcronológica y estado de madurez chilenos / Physical fitness in young Chilean soccer and non-football players by chronological age and maturity stage

Introducción: Durante el periodo de la adolescencia se producen cambios en el cuerpo, siendo importante identificar las diferencias individuales de madurez entre los adolescentes. En el caso de los futbolistas, esto puede generar diferencias en su rendimiento deportivo. Objetivo: Comparar el desempeño físico de jóvenes futbolistas vs escolares (no futbolistas) según edad cronológica y estado de madurez. Metodología: Se efectuó un estudio de tipo descriptivo-comparativo en 139 jóvenes (62 futbolistas con 16,38±1,30 años y 77 escolares con 16,35±1,45años). La selección de la muestra fue de tipo no probabilística por conveniencia. El rango de edad fue entre 14 a 18 años de edad. Se evaluó el peso, la estatura, velocidad 20 metros, salto horizontal (SH), y la prueba de aptitud aeróbica de Leger. Se calculó el índice de masa corporal (IMC), los años de pico de velocidad de crecimiento (APVC), y el VO2max absoluto y relativo. Resultados: Los jóvenes futbolistas presentaron mayor VO2max absoluto y relativo en comparación con sus similares escolares, tanto por edad cronológica y estado de madurez. Hubo correlación positiva significativa (p<0.05) entre la edad y los APVC con el VO2max absoluto y salto horizontal, y negativa con la velocidad de 20 metros. No hubo correlación entre la edad y APVC con el VO2máx relativo (edad y VO2máx, r= 0.10, p=0.023 y APVC y VO2máx, r= 0.07, p= 0.036). Conclusión: Los jóvenes futbolistas presentaron un mejor VO2max absoluto y relativo, SH y velocidad 20m en relación a los no-futbolistas, tanto por edad cronológica y estado de madurez, aunque, el desempeño físico se observa mejor por estado de madurez, especialmente en el VO2max y en el SH. Estos resultados sugieren que los profesionales del futbol deben considerar el control del estado de madurez como una alternativa para categorizar a los futbolistas cuando se evalúa y trabaja el desempeño físico.(AU)

Introduction: During the adolescent period, changes ingrowth and body composition occur, and it is important toidentify individual differences in maturity among adolescents. In the case of soccer players, they may show better physicalfitness than their non-football players.Objective: To compare the physical fitness of young soccer players vs non-football players, according to chronologicalage and maturity status.Methodology: A descriptive-comparative study was carriedout in 139 young people (62 soccer players aged 16.38±1.30years and 77 schoolchildren aged 16.35±1.45 years). Thesample selection was non-probabilistic by convenience. Theage range ranged from 14 to 18 years old. Weight, height,speed 20 meters, horizontal jump (SH), and Leger’s aerobicfitness test were evaluated. Body mass index (BMI), peak years of growth velocity (APVC), and absolute and relativeVO2max were calculated.Results: Young soccer players presented higher absoluteand relative VO2max compared to their similar non-footballplayers, both by chronological age and maturity status. Therewas significant positive correlation (p<0.05) between age andAPVC with absolute VO2max and horizontal jump, and negative with 20-meter speed. There was no correlation betweenage and APVC with relative VO2max (age and VO2max, r=0.10, p=0.023 and APVC and VO2max, r= 0.07, p= 0.036).Conclusion: Young soccer players presented better absolute and relative VO2max, SH and 20m speed in relation tonon-football players, both by chronological age and maturitystatus, although, physical performance is better observed bymaturity status, especially in VO2max and SH. These resultssuggest that professionals working in grassroots soccershould consider the control of maturity status as an alternative to categorize soccer players when evaluating and workingon physical performance.(AU)

Systematic review of the anthropometric profile of female futsal players 2010-2020.

The objective was to summarize the scientific literature on the anthropometric characteristics of female futsal players. A systematic review documentary study was carried out. SCOPUS, PUBMED and SCIELO databases were used to search for information on primary studies related to the anthropometric profile of women's indoor soccer (elite and non-elite). The keywords used were: futsal, female, anthropometry. The range of years for the search was from 2010 to 2020. To analyze anthropometric differences, two groups were formed: group A: elite and group B: non-elite. 31 primary studies were identified, 22 (71%) in Scopus, 5 (16.1%) in PUBMED and 4 (12.9%) in SCIELO. Three publication languages were considered (English, Spanish and Portuguese) and 6 countries were identified (Brazil, Spain, Iran, Turkey, Venezuela and Italy). Players in the elite group evidenced higher weight, height, and BMI relative to their non-elite counterparts. Discrepancy in anthropometric characteristics between elite and non-elite players was verified. These results suggest that in order to participate in competitions at the highest level in women's futsal, they should have greater weight, height and BMI than their non-elite counterparts.

Measuring intramolecular connectivity in long RNA molecules using two-dimensional DNA patch-probe arrays.

We describe a simple method to infer intramolecular connections in a population of long RNA molecules in vitro. First we add DNA oligonucleotide "patches" that perturb the RNA connections, then we use a microarray containing a complete set of DNA oligonucleotide "probes" to record where perturbations occur. The pattern of perturbations reveals couplings between different regions of the RNA sequence, from which we infer connections as well as their prevalences in the population. We validate this patch-probe method using the 1,058-nucleotide RNA genome of satellite tobacco mosaic virus (STMV), which has previously been shown to have multiple long-range connections. Our results not only indicate long duplexes that agree with previous structures but also reveal the prevalence of competing connections. Together, these results suggest that globally-folded and locally-folded structures coexist in solution. We show that the prevalence of connections changes when pseudouridine, an important component of natural and synthetic RNA molecules, is substituted for uridine in STMV RNA.

Fat-free mass and maturity status are determinants of physical fitness performance in schoolchildren and adolescents

Abstract Objectives: The objective of the study was to verify whether (FFM), maturity status (MS) and chronological age (CA) are determinants of physical fitness performance, and to analyze FFM and physical performance aligned by CA and MS in children and adolescents. Methods: A descriptive correlational study was carried out in 863 schoolchildren. Weight, height, and waist circumference (WC) were evaluated. Body mass index (BMI), FFM, fat mass (FM), MS (Age at peak height velocity, APHV) were calculated. The physical tests of velocity 20 m, agility 5 m × 10rep, and horizontal jump (HJ) were evaluated. Results: The APHV was estimated in boys at 14.0 ± 0.36APHV and in girls at 11.96 ± 0.49APHV. The relationships between CA and APHV with FFM was r = 0.80 in boys and r = 0.44 to 0.45 in girls. The relationships between FFM and physical tests in boys were [HJ (r = 0.70), agility 5m × 10rep (r = -0.68), velocity (r = -0.61)] and in girls [HJ (r = 0.42), agility 5m × 10rep (r = -0.52), velocity (r = -0.20)]. The differences in FFM and physical fitness tests were more pronounced when aligned by APHV than by CA. Conclusion: It was verified that both FFM, CA, and APHV are determinants of physical fitness performance. In addition, the APHV should be introduced in physical education as a means of ranking physical performance among schoolchildren.

Fat-free mass and maturity status are determinants of physical fitness performance in schoolchildren and adolescents.

OBJECTIVES: The objective of the study was to verify whether (FFM), maturity status (MS) and chronological age (CA) are determinants of physical fitness performance, and to analyze FFM and physical performance aligned by CA and MS in children and adolescents. METHODS: A descriptive correlational study was carried out in 863 schoolchildren. Weight, height, and waist circumference (WC) were evaluated. Body mass index (BMI), FFM, fat mass (FM), MS (Age at peak height velocity, APHV) were calculated. The physical tests of velocity 20 m, agility 5 m x 10rep, and horizontal jump (HJ) were evaluated. RESULTS: The APHV was estimated in boys at 14.0 ± 0.36APHV and in girls at 11.96 ± 0.49APHV. The relationships between CA and APHV with FFM was r = 0.80 in boys and r = 0.44 to 0.45 in girls. The relationships between FFM and physical tests in boys were [HJ (r = 0.70), agility 5m x 10rep (r = -0.68), velocity (r = -0.61)] and in girls [HJ (r = 0.42), agility 5m x 10rep (r = -0.52), velocity (r = -0.20)]. The differences in FFM and physical fitness tests were more pronounced when aligned by APHV than by CA. CONCLUSION: It was verified that both FFM, CA, and APHV are determinants of physical fitness performance. In addition, the APHV should be introduced in physical education as a means of ranking physical performance among schoolchildren.

Comparación de parámetros antropométricos y de composición corporal de futbolistas profesionales / A Comparison of Anthropometric Parameters and the Body Composition of Professional Soccer Players

Resumen El presente estudio tuvo por objetivo comparar los parámetros antropométricos y de composición corporal en futbolistas profesionales en cinco temporadas. Se efectuó un estudio transversal (comparativo). Se estudió a 120 futbolistas, donde cada cohorte por año se evaluó a 24 futbolistas. El rango de edad fue de 18 a 37 años. Se evaluó a los futbolistas al inicio de cada temporada en los años 2012 a 2016: Se midió el peso, la estatura, seis pliegues cutáneos (Tríceps, subescapular, supra-iliaco, abdominal, muslo y pantorrilla). Se calculó el Índice de Masa corporal IMC, % de grasa, la masa grasa y masa libre de grasa MLG. El tejido adiposo se agrupó en tres grupos (brazo: (tricpes+subescapular, tronco: suprailiaco+abdominal, Piernas: muslo+pantorrilla). Hubo diferencias en el peso corporal, la estatura, la sumatoria de los 6 pliegues y la MLG a lo largo de los 5 años. [año 2012 (Peso: 76,6±7.8kg, estatura: 177.6±5.7cm, Pliegues: 58.7±12.8mm, MLG: 64.5±6.3mm), año 2013: (Peso: 77.8±6.4kg, Estatura: 178,4±4.4, Pliegues: 60.1±15.9mm, MLG:66.3±3.5mm), año 2014: (Peso: 74.9±5.7kg, Estatura: 177.0±5.8cm, Pliegues: 54.4±14.7mm, MLG: 64.5±4.5kg), año 2015: (Peso: 74.1±6.8kg, Estatura: 176.1±5.5cm, Pliegues: 54.9±15.6mm, MLG: 63.8±4.6kg), año 2016: (Peso: 72.7±kg, Estatura: 175.3±6.9kg, Pliegues: 50.8±12.mm, MLG: 62.8±5.9kg)]. Este estudio verificó que el perfil antropométrico y el tejido adiposo de los futbolistas fueron disminuyendo en cada temporada, mientras que la MLG reflejó similares valores en cada uno de las cohortes evaluadas.

Abstract The present cross-sectional (comparative) study aimed to compare the anthropometric and body composition parameters in professional soccer players over five seasons. It was conducted on 120 soccer players grouped in a cohort of 24 subjects per year. The age range was 18 to 37 years. The footballers were evaluated at the beginning of each season from 2012 to 2016; weight, height, six skin folds (triceps, subscapularis, supra-iliac, abdominal, thigh, and calf) were evaluated from 2012 to 2015. The Body Mass Index (BMI), fat percentage, fat mass, and FFM were calculated. The adipose tissue was grouped into three groups: arm (triceps + subscapular), trunk (supra iliac + abdominal), and legs (thigh + calf). Body weight, height, the sum of the 6 folds, and the MLG varied during the 5 years. For 2012 the results were the following: Weight, 76.6 ± 7.8kg; Height, 177.6 ± 5.7cm; Folds, 58.7 ± 12.8mm; MLG, 64.5 ± 6.3mm). In 2013, these were the results: Weight, 77.8 ± 6.4kg; Height, 178, 4 ± 4.4; Folds, 60.1 ± 15.9mm; MLG, 66.3 ± 3.5mm). These were the measures obtained in 2014: Weight, 74.9 ± 5.7kg; Height, 177.0 ± 5.8cm; Folds, 54.4 ± 14.7mm; MLG, 64.5 ± 4.5kg ). And these were of the year 2015: Weight, 74.1 ± 6.8kg; Height, 176.1 ± 5.5cm; Folds, 54.9 ± 15.6mm; MLG, 63.8 ± 4.6kg). Finally, in 2016 these were the measures collected: Weight, 72.7 ± kg; Height, 175.3 ± 6.9 kg; Folds, 50.8 ± 12.mm; MLG, 62.8 ± 5.9kg. This study verified that the soccer players' anthropometric profile and adipose tissue decreased each season, while the MLG reflected similar values in each of the evaluated cohorts.

Resumo O presente estudo teve como objetivo comparar os parâmetros antropométricos e de composição corporal em jogadores profissionais de futebol durante cinco temporadas. Foi realizado um estudo transversal (comparativo). Foi estudado um total de 120 jogadores de futebol, onde cada coorte por ano foram avaliados 24 jogadores. A faixa etária era de 18 a 37 anos. Os futebolistas foram avaliados no início de cada temporada, nos anos de 2012 a 2016. Foram medidas altura, peso, seis dobras da pele (tríceps, subescapular, supra ilíaca, abdominal, coxa e calcanhar). Foram calculados índice de massa corporal IMC, % de gordura, massa de gordura e massa livre de gordura MLG. O tecido adiposo foi agrupado em três grupos (braço: tríceps + subescapular, tronco: suprailíaco + abdominal, pernas: coxa + calcanhar). Houve diferenças no peso corporal, na altura, a soma de 6 dobras e a MLG ao longo dos 5 anos: ano 2012 (Peso: 76,6±7,8kg, Altura: 177,6±5,7cm, Dobras: 58,7±12,8mm, GLM: 64,5±6,3mm), ano 2013 (Peso: 77,8±6,4kg, Altura: 178,4±4,4, Dobras: 60,1±15,9mm, GLM:66,3±3.5mm), ano 2014 (Peso: 74,9±5,7kg, Altura: 177,0±5,8cm, Dobras: 54,4±14,7mm, GLM: 64,5±4,5kg), ano 2015 (Peso: 74,1±6,8kg, Altura: 176,1±5,5cm, Dobras: 54,9±15,6mm, GLM: 63,8±4,6kg), ano 2016 (Peso: 72,7±kg, Altura: 175,3±6,9kg, Dobras: 50,8±12,mm, GLM: 62,8±5,9kg). Este estudo verificou que o perfil antropométrico e o tecido adiposo dos jogadores de futebol diminuíram em cada temporada, enquanto que a MLG refletiu valores similares em cada um dos coortes avaliados.

Active exterior cloaking for the two-dimensional Helmholtz equation with complex wavenumbers and application to thermal cloaking.

We design sources for the two-dimensional Helmholtz equation that can cloak an object by cancelling out the incident field in a region, without the sources completely surrounding the object to hide. As in previous work for real positive wavenumbers, the sources are also determined by the Green identities. The novelty is that we prove that the same approach works for complex wavenumbers which makes it applicable to a variety of media, including media with dispersion, loss and gain. Furthermore, by deriving bounds on Graf's addition formulas with complex arguments, we obtain new estimates that allow to quantify the quality of the cloaking effect. We illustrate our results by applying them to achieve active exterior cloaking for the heat equation. This article is part of the theme issue 'Wave generation and transmission in multi-scale complex media and structured metamaterials (part 2)'.

Single-particle studies of the effects of RNA-protein interactions on the self-assembly of RNA virus particles.

Understanding the pathways by which simple RNA viruses self-assemble from their coat proteins and RNA is of practical and fundamental interest. Although RNA-protein interactions are thought to play a critical role in the assembly, our understanding of their effects is limited because the assembly process is difficult to observe directly. We address this problem by using interferometric scattering microscopy, a sensitive optical technique with high dynamic range, to follow the in vitro assembly kinetics of more than 500 individual particles of brome mosaic virus (BMV)-for which RNA-protein interactions can be controlled by varying the ionic strength of the buffer. We find that when RNA-protein interactions are weak, BMV assembles by a nucleation-and-growth pathway in which a small cluster of RNA-bound proteins must exceed a critical size before additional proteins can bind. As the strength of RNA-protein interactions increases, the nucleation time becomes shorter and more narrowly distributed, but the time to grow a capsid after nucleation is largely unaffected. These results suggest that the nucleation rate is controlled by RNA-protein interactions, while the growth process is driven less by RNA-protein interactions and more by protein-protein interactions and intraprotein forces. The nucleated pathway observed with the plant virus BMV is strikingly similar to that previously observed with bacteriophage MS2, a phylogenetically distinct virus with a different host kingdom. These results raise the possibility that nucleated assembly pathways might be common to other RNA viruses.

Reference values for bone density and bone mineral content from 5 to 80 years old in a province of Chile.

Background: The assessment of bone health throughout the life cycle is essential to determine fracture risk. The objectives of the work were (a) compare bone mineral density and content with international references from the United States, (b) determine maximum bone mass, (c) propose references for bone health measurements from ages 5 to 80 years old. Methods: Research was carried out on 5,416 subjects. Weight and height were measured. Body Mass Index (BMI) was calculated. The total body was scanned using dual energy X-ray absorptiometry (DXA). Information was extracted from the bone health measures (bone mineral density (BMD) and bone mineral content (BMC)) for both sexes, according to pediatric and adult software. Results and Discussion: Differences were identified between the mean values of Chilean and American men for BMD (~0.03 to 0.11 g/cm2) and BMC (~0.15 to 0.46 g). Chilean females showed average values for BMD similar to the US references (~-0.01 to 0.02 g/cm2). At the same time, they were relatively higher for BMC (~0.07 to 0.33 g). The cubic polynomial regression model reflected a relationship between BMD and BMC with chronological age in both sexes. For males, R2 was higher (R2 = 0.72 and 0.75) than for females (R2 = 0.59 and 0.66). The estimate of maximum bone mass (MBM) for males emerged at 30 years old (1.45 ± 0.18 g/cm2 of BMD and 3.57 ± 0.60 g of BMC) and for females at age 28 (1.22 ± 0.13 g/cm2 of BMD and 2.57 ± 0.44 g of BMC). The LMS technique was used to generate smoothed percentiles for BMD and BMC by age and sex. Results showed that maximum bone mass occurred in females at age 28 and in males at 30. Reference values obtained from this research may be used to evaluate bone health, diagnose bone fragility and osteoporosis in individuals and regional population groups.

Relationship between age and handgrip strength: Proposal of reference values from infancy to senescence.

Introduction: Measurement of hand grip strength (HGS) has been proposed as a key component of frailty and has also been suggested as a central biomarker of healthy aging and a powerful predictor of future morbidity and mortality. Objectives: (a) To determine whether a nonlinear relationship model could improve the prediction of handgrip strength (HGS) compared to the linear model and (b) to propose percentiles to evaluate HGS according to age and sex for a regional population of Chile from infancy to senescence. Methods: A cross-sectional descriptive study was developed in a representative sample of the Maule region (Chile). The volunteers amounted to 5,376 participants (2,840 men and 2,536 women), with an age range from 6 to 80 years old. Weight, height, HGS (right and left hand) according to age and sex were evaluated. Percentiles were calculated using the LMS method [(L (Lambda; asymmetry), M (Mu; median), and S (Sigma; coefficient of variation)]. Results and discussion: There were no differences in HGS from 6 to 11 years of age in both sexes; however, from 12 years of age onwards, males presented higher HGS values in both hands (p < 0.05). The linear regression between age with HGS showed values of R 2 = 0.07 in males and R 2 = 0.02 in females. While in the non-linear model (cubic), the values were: R 2 = 0.50 to 0.51 in men and R 2 = 0.26 in women. The percentiles constructed by age and sex were: P5, P15, P50, P85, and P95 by age range and sex. This study demonstrated that there is a nonlinear relationship between chronological age with HGS from infancy to senescence. Furthermore, the proposed percentiles can serve as a guide to assess and monitor upper extremity muscle strength levels at all stages of life.

Comparación de la adiposidad corporal y aptitud aeróbica de adolescentes brasileros y chilenos / Comparison of body adiposity and aerobic fitness in Brazilian and Chilean adolescents

Fundamentos: La aptitud aeróbica y la adiposidad corporal son importantes marcadores de salud que deben ser fomentados para mejorar el estilo de vida y la salud general de los adolescentes. El objetivo del estudio fue comparar la adiposidad corporal y aptitud aeróbica de adolescentes brasileros y chilenos de colegios públicos. Métodos: Se desarrolló un estudio descriptivo (comparativo) en adolescentes que asisten a colegios públicos de una región de Brasil y Chile. El rango de edad de los estudiantes fue de 14 a 17 años. Se seleccionaron dos colegios localizados en la zona urbana de Campinas (Brasil) y Talca (Chile). Se evaluó el peso, la estatura y la aptitud aeróbica (Test de ida y vuelta de 20 m). Se calculó el VO2max (ml/kg-1/min-1) y el índice de masa corporal (IMC). Se clasificó el estado nutricional por IMC. Resultados: En hombres, el promedio de edad de adolescentes chilenos fue 15,41 ± 0,75 años, IMC fue 22,79 ± 3,58 kg/m2 y la aptitud aeróbica fue de 44,1 ± 6,6 ml/kg-1/min-1. En los adolescentes brasileros, la edad fue de 14,78 ± 0,64 años, IMC de 21,90 ± 4,59 kg/m2 y la aptitud aeróbica fue de 41,8 ± 6,3 ml/kg-1/min-1. En mujeres, el promedio de edad en las mujeres chilenas fue de 15,40 ± 0,75 años, el IMC fue de 22,80 ± 3,58 kg/m2 y aptitud aeróbica de 36,8 ± 4,3 kg/m2. En las mujeres brasileras la edad fue de 14,80 ± 0,64 años, IMC fue 21,90 ± 4,88 kg/m2 y aptitud aeróbica de 37,0 ± 3,6 ml/kg-1/min-1. Las relaciones entre adiposidad corporal y aptitud aeróbica en ambos sexos y países oscilaron entre (R= -0,32 a -0,41). Conclusiones: No se observó diferencias en la adiposidad corporal y aptitud aeróbica entre adolescentes de Chile y Brasil, además, se determinó que los adolescentes clasificados con peso normal, reflejaron una mayor aptitud aeróbica que sus similares con exceso de peso corporal. (AU)

Background: Aerobic fitness and body adiposity are important health markers that should be encouraged to improve the lifestyle and general health of adolescents. The aim of the study was to compare body adiposity and aerobic fitness of Brazilian and Chilean adolescents from public schools. Methods: A descriptive (comparative) study was developed in adolescents attending public schools in a region ofBrazil and Chile. The age range of the students was 14 to 17 years. Two schools located in the urban area ofCampinas (Brazil) and Talca (Chile) were selected. Weight, height and aerobic fitness (20 m round-trip test) were evaluated. VO2max (ml/kg-1/min-1) and body mass index (BMI) were calculated. Nutritional status was classified by BMI. Results: In men, the average age of Chilean adolescents was 15.41 ± 0.75 years, BMI was 22.79 ± 3.58 kg/m2 and aerobic fitness was 44.1 ± 6.6 ml/kg-1/min-1. In Brazilian adolescents, age was 14.78 ± 0.64 years, BMI was 21.90 ± 4.59 kg/m2 and aerobic fitness was 41.8 ± 6.3 ml/kg-1/min-1. In women, the average age in Chilean women was 15.40 ± 0.75 years, BMI was 22.80 ± 3.58 kg/m2 and aerobic fitness was 36.8 ± 4.3 kg/m2. In Brazilian women, age was 14.80 ± 0.64 years, BMI was 21.90 ± 4.88 kg/m2 and aerobic fitness was 37.0 ± 3.6 ml/kg-1/min-1. The relationships between body adiposity and aerobic fitness in both sexes and countries ranged from (R= -0.32 to - 0.41).Conclusions: No differences were observed in body adiposity and aerobic fitness between adolescents from Chileand Brazil, moreover, it was determined that adolescents classified as normal weight, reflected a higher aerobicfitness than their peers with excess body weight. (AU)

Systematic review of aquatic physical exercise programs on functional fitness in older adults.

The practice of physical exercise is recommended in the prevention of the deterioration of neuromuscular functions in aging. The objectives of this systematic review were to describe the protocols used and the functional fitness indicators evaluated in aquatic exercise programs in adults aged 50 to 80 years. The Pubmed database was used. The keywords were: 1) Physical exercise program or protocols or duration or type of exercise or aquatic exercise, frequency or intensity or indicators; 2) Adults or older adults; 3) Training or indicators, functional fitness, physical fitness. The search strategy considered the components of the Population, Interventions, Comparators, Outcomes, and Study design (PICOS) tool. Nine experimental studies were identified. These studies developed protocols to improve functional fitness in adults aged 50 to 80 years. They were based on sessions of 2 to 5 per week, the work time per session was 30 to 60min, intensities varied between 50 to 95% and totaled between 4 to 24 weeks of intervention. The activities were based on aquatic gymnastic exercises aimed at muscular strengthening of the upper and lower extremities, as well as coordination, balance, agility, cycling and walking exercises submerged in water. The protocols developed to improve functional fitness in adults aged 50 to 80 years were based on general physical exercise prescription guidelines (frequency, duration, intensity and type of activity). The application of aquatic exercises based on gymnastic exercises can provoke positive responses on functional fitness if worked at least 2 to 5 times per week, 30 to 60min/day and at intensities of 50 to 95%. These systematized indicators can be used by professionals working with adults to create and promote aquatic programs to improve functional fitness.

Masa grasa por edad cronológica y biológica: Comparación de dos ecuaciones de regresión en niños y adolescentes / Fat mass by chronological and biological age: comparison of two regression equations in children and adolescents

Fundamentos: Durante la infancia y la adolescencia, es importante controlar el tejido adiposo intra-abdominal, ya que durante el crecimiento y desarrollo se producen cambios significativos en la composición corporal. Los objetivos del estudio fueron comparar la masa grasa (MG) entre dos ecuaciones, basada por edad cronológica y por estado de madurez y verificar los pliegues cutáneos que mejor predicen la Masa Grasa de ambas ecuaciones. Métodos: Se efectuó un estudio descriptivo correlacional en 346 niños y adolescentes de Talca (Chile). La selección dela muestra fue probabilística (estratificada). Se evaluó la edad, peso, estatura de pie, estatura sentada, circunferencia de la Cintura (CC) y cinco pliegues cutáneos (bicipital, tricipital, subescapular, suprailiaco y abdominal). Se calculó el estado de madurez por medio del pico de velocidad de crecimiento (APVC). Se calculó la MG por medio de dos ecuaciones (una basada en la edad cronológica EC y CC y la otra por estado de Madurez (APVC y CC) para ambos sexos. Resultados: No hubo diferencias significativas entre ambas ecuaciones cuando se calculó la MG en ambos sexos(p>0,05). Los pliegues cutáneos (bíceps, tricipital, subescapular, supra iliaco, abdominal, sumatoria de dos, tres y cinco pliegues) mostraron similares coeficientes de determinación, tanto por la ecuación por EC (R2 = 23 a 48%), como por la ecuación por APVC (R2 = 39 a 69%). Las prevalencias en las categorías de MG estimadas por ambas ecuaciones fueron similares en hombres (X2 = 1,01, GL: 2, p = 0,60) y en mujeres (X2 = 0,44, GL: 2, p = 0,80).Conclusiones: Ambas ecuaciones de regresión que estiman la MG, tanto por EC y estado de madurez (APVC) son útiles para niños y adolescentes chilenos. Los resultados sugieren el uso y aplicación para evaluar la acumulación de tejido adiposo en contextos clínicos y epidemiológicos. (AU)

Background: During childhood and adolescence, it is important to control intra-abdominal adipose tissue, since significant changes in body composition occur during growth and development. The objectives of the study were to compare fat mass (FM) between two equations, based on chronological age and maturity stage, and to verify the skin folds that best predict Fat Mass of both equations. Methods: A descriptive correlational study was carried out in 346 children and adolescents from Talca (Chile). The selection of the sample was probabilistic (stratified). Age, weight, standing height, sitting height, waist circumference(WC) and five skinfolds (bicipital, tricipital, subscapular, suprailiac and abdominal) were evaluated. The state ofmaturity was calculated by means of the peak growth rate(APHV). MG was calculated using two equations (one based on chronological age CA and WC and the other based onAPHV and WC) for both sexes. Results: There were no significant differences between both equations when MG was calculated in both sexes (p>0.05). The skin folds (biceps, tricipital, subscapular, suprailiac, abdominal, sum of two, three and five folds) showed similar coefficients of determination, both by the CA equation (R2 = 23 to 48%), and by the equation by APHV(R2 = 39 to 69%). The prevalence’s in the FM categories estimated by both equations were similar in men (X2 = 1.01,GL: 2, p = 0.60) and in women (X2 = 0.44, GL: 2, p = 0, 80). Conclusions: Both regression equations that estimate FM, both by CA and maturity stage (APHV) are useful for Chilean children and adolescents. The results suggest the use and application to evaluate the accumulation of adipose tissue in clinical and epidemiological contexts. (AU)

Regulation data for the horizontal jump of children and adolescents.

The Horizontal Jump (HJ) is a daily tool that could be used to categorize the level of muscle fitness performance of the lower limbs. The goal was to compare the muscle fitness with those of international studies and to propose percentiles to assess the HJ performance of children and adolescents. A cross-sectional study was conducted. A total number of 3023 children and adolescents between the ages of 6.0 to 17.9 were studied. Weight, height, waist circumference (WC), and lower limb muscle fitness were evaluated. The student HJ performance values in Chile were inferior when compared to HJ performance in Brazil, Poland and Europe. For the Greek study, differences occurred only from age 6 to 15 years old. In comparison to Colombia, students showed better muscle fitness performance. These differences appeared in childhood and lasted until the beginning of adolescence. Percentiles were created to assess the lower limb fitness being an easy tool to be used and applied to classify lower limb strength.

Wave-Driven Assembly of Quasiperiodic Patterns of Particles.

We theoretically show that a superposition of plane waves causes small (compared to the wavelength) particles dispersed in a fluid to assemble in quasiperiodic two or three-dimensional patterns. We experimentally demonstrate this theory by using ultrasound waves to assemble quasiperiodic patterns of carbon nanoparticles in water using an octagonal arrangement of ultrasound transducers, and we document good agreement between theory and experiments. The theory also applies to obtaining quasiperiodic patterns in other situations where particles move with linear waves, such as optical lattices.

Changes in diversity and distribution of native fish due to the presence of two invasive species in the Atacames River, northwestern Ecuador / Cambios en diversidad y distribución de peces nativos por la presencia de dos especies invasoras en el río atacames, noroccidente del ecuador

RESUMEN La interpretación de la diversidad biológica puede resultar muy compleja, ya que existe una dinámica basada en el origen y en la diversificación de las especies, así como en los efectos antrópicos, tales como la introducción de especies invasoras, cuya consecuencia puede conducir a la extinción local de especies nativas. El objetivo de este trabajo fue analizar la variación temporal (2012 y 2017), tanto en composición como en distribución de la ictiofauna a lo largo del río Atacames, noroccidente del Ecuador. En 2012 se registró: 1) la presencia de Astyanax ruberrimus que se extinguió localmente para el 2017; y 2) la presencia de la tilapia (Orechromis niloticus) como única especie introducida a la que se sumó el guppy (Poecilia gillii) para el 2017. Adicionalmente, el aumento en las actividades humanas condujo a un arreglo en la diversidad, abundancia y distribución de peces a lo largo del cauce, lo que determinó además que algunas especies se dispersaran hacia la zona alta de la cuenca.

ABSTRACT The interpretation of biological diversity can be very complex, as it exists a dynamic based on the origin and diversification of species, in addition to anthropogenic effects, such as the introduction of invasive species, which can result in the local extinction of the native ones. The aim of this study was to analyze the temporal variation (2012 and 2017), in composition and distribution of the ichthyofauna along the Atacames River in northwestern Ecuador. In 2012 we recorded: 1) the presence of Astyanax ruberrimus, which was reported locally extinct by 2017; and 2) the tilapia (Orechromis niloticus) as the only introduced fish species present until 2017, when the addition of the non-native guppy (Poeciliagillii) occurred . In addition, the increase in human activities conduced to change in diversity, abundance and distribution of fish along the watercourse, which resulted in dispersing of some species towards the upper reaches of the river basin.