Análisis del peso de las mochilas en estudiantes de enseñanza básica: estudio de corte transversal / Analysis of the weight of backpacks in basic education students: cross-sectional study

INTRODUCCIÓN: La mayoría de los establecimientos educacionales tienen una jornada escolar completa, generando que el estudiante transporte mayor cantidad de útiles escolares en su mochila. OBJETIVO: Analizar el peso promedio de las mochilas de espalda en estudiantes de educación básica de la comuna de Copiapó. METODOLOGÍA: se realizó un estudio descriptivo de corte transversal con alcance correlacional, la muestra estuvo constituida por 286 estudiantes (139 varones y 147 mujeres) de educación básica, de un establecimiento escolar de la comuna de Copiapó. Se analizó el peso corporal, la altura y el peso de las mochilas durante una semana, mediante una plataforma de fuerza y estadiómetro. RESULTADOS: Se encontró que entre los días lunes a jueves los estudiantes llevaban en su mochila un peso que sobrepasaba el 10/ de su peso corporal. Asimismo, las mochilas de espaldas son las más utilizadas en comparación con las mochilas con ruedas, con un 88,1% de la muestra. Sin embargo, las mochilas de espalda presentaron menor peso al compararlas con las mochilas con ruedas, las cuales tuvieron valores cercanos al 20% del peso corporal. CONCLUSIÓN: La mayoría de los estudiantes transportaban en sus mochilas, pesos que superan el 10% de peso recomendado, siendo las mochilas con rueda las de mayor peso. Se recomienda desarrollar normas establecidas dentro de los colegios, para evitar el traslado de dichas cargas y prevenir alteraciones posturales, biomecánicas y fisiológicas.

INTRODUCTION: Most educational establishments have a full school day, causing the student to carry a greater number of school supplies in their backpack. OBJECTIVE: To analyze the average weight of backpacks in basic education students of the Copiapó district. METHODOLOGY: a descriptive cross-sectional study with correlational scope was carried out, the sample consisted of 286 students (139 men and 147 women) of basic education, from a school in the district of Copiapó. Body weight, height and backpack weight were analyzed for one week, using a force platform and stadiometer. RESULTS: It was found that between Monday and Thursday the students carried a weight in their backpack that exceeded 10% of their body weight. Likewise, backpacks on the back are the most used compared to backpacks with wheels, with 88.1% of the sample. However, the backpacks presented less weight when compared to the backpacks with wheels, which had values close to 20% of body weight. CONCLUSION: Most of the students carried weights in their backpacks that exceed 10% of the recommended weight, with wheeled backpacks being the heaviest. It is recommended to develop established norms within the schools, to avoid the transfer of said loads and prevent postural, biomechanical and physiological alterations.

A framework for allocating conservation resources among multiple threats and actions.

Land managers decide how to allocate resources among multiple threats that can be addressed through multiple possible actions. Additionally, these actions vary in feasibility, effectiveness, and cost. We sought to provide a way to optimize resource allocation to address multiple threats when multiple management options are available, including mutually exclusive options. Formulating the decision as a combinatorial optimization problem, our framework takes as inputs the expected impact and cost of each threat for each action (including do nothing) and for each overall budget identifies the optimal action to take for each threat. We compared the optimal solution to an easy to calculate greedy algorithm approximation and a variety of plausible ranking schemes. We applied the framework to management of multiple introduced plant species in Australian alpine areas. We developed a model of invasion to predict the expected impact in 50 years for each species-action combination that accounted for each species' current invasion state (absent, localized, widespread); arrival probability; spread rate; impact, if present, of each species; and management effectiveness of each species-action combination. We found that the recommended action for a threat changed with budget; there was no single optimal management action for each species; and considering more than one candidate action can substantially increase the management plan's overall efficiency. The approximate solution (solution ranked by marginal cost-effectiveness) performed well when the budget matched the cost of the prioritized actions, indicating that this approach would be effective if the budget was set as part of the prioritization process. The ranking schemes varied in performance, and achieving a close to optimal solution was not guaranteed. Global sensitivity analysis revealed a threat's expected impact and, to a lesser extent, management effectiveness were the most influential parameters, emphasizing the need to focus research and monitoring efforts on their quantification.

Un Marco de Referencia para Asignar Recursos para la Conservación entre Múltiples Amenazas y Acciones Resumen Los administradores de tierras deciden cómo asignar recursos entre múltiples amenazas que pueden abordarse por medio de múltiples acciones. Adicionalmente, estas acciones varían en viabilidad, efectividad y costo. Buscamos proporcionar una manera para optimizar la asignación de recursos para abordar varias amenazas cuando están disponibles muchas opciones de manejo, incluyendo opciones mutuamente excluyentes. Con una formulación de la decisión como un problema combinatorio de optimización, nuestro marco de referencia toma como entradas el impacto esperado y el costo de cada amenaza para cada acción (incluyendo hacer nada) y para cada presupuesto generalizado identifica la acción óptima a realizar ante cada amenaza. Comparamos la solución óptima con una aproximación de un algoritmo avaricioso fácil de calcular y una variedad de esquemas plausibles de clasificación. Aplicamos el marco de trabajo al manejo de múltiples especies de plantas introducidas en las áreas alpinas de Australia. Desarrollamos un modelo de invasión para predecir el impacto esperado en 50 años para cada combinación de especie-acción que consideró el estado actual de invasión para cada especie (ausente, localizada, ampliamente distribuida), la probabilidad de invasión, la tasa de esparcimiento, el impacto, cuando abundante, de cada especie y la efectividad de manejo de cada combinación especie-acción. Descubrimos que la acción recomendada para una amenaza cambia con el presupuesto, que no existe una acción única de manejo óptimo para cada especie y que considerar más de una acción candidata puede incrementar sustancialmente la eficiencia general del plan de manejo. La solución aproximada (solución clasificada por rentabilidad) tuvo un buen desempeño cuando el presupuesto fue igual al costo de las acciones prioritarias, lo que indica que esta estrategia sería efectiva si el presupuesto está fijado como parte del proceso de priorización. Los esquemas de clasificación variaron en cuanto a desempeño, y lograr una solución cercana a lo óptimo no estuvo garantizado. El análisis de sensibilidad global reveló que el impacto esperado de una amenaza y, a menor grado, la efectividad del manejo no fueron los parámetros con mayor influencia, lo que enfatiza la necesidad de enfocar la investigación y los esfuerzos de monitoreo en la cuantificación del impacto esperado y la efectividad del manejo.

Evaluation by ultrasound of the hips of babies carried in baby carriers. / Exploración ecográfica de las caderas del bebé en mochilas de porteo.

BACKGROUND AND OBJECTIVE: Hip dysplasia has been associated with risk factors such as breech presentation, female gender or family history. However, external factors, such as the use of baby carriers, seem to influence the development of the hip in the first months of life. The aim of this study is to evaluate the position of the hips of babies placed in different types of baby carriers by ultrasound image. METHOD: An ultrasound study of the hips of healthy babies between 1.5 and 3.5 months of age was carried out, when the children were carried in three different baby backpacks, which provide different degrees of support for the babies' thighs. All hips were typeI according to the Graf classification. Graf's alpha angle, acetabular coverage and distance to the pubis were assessed at baseline (examination table) and when the children were carried in the three different backpacks. RESULTS: In all cases, the babies showed normal values in the three studied parameters, without statistically significant differences between any of the situations. There were also no differences in the ultrasound parameters related to the sex, age or weight of the baby. CONCLUSIONS: The right hip of the babies shows normal ultrasound parameters when placed in any of the baby carriers studied.

Prevalência de dor nas costas em mulheres e fatores associados / Prevalence of back pain in women and associated factors

A ocorrência dor nas costas deve-se às modificações corporais que acompa-nham os indivíduos com o passar dos anos. Entre fatores de risco encontramos a alteração biomecânica da coluna vertebral causada pelo excesso de carga mecânica e pela postura incorreta. Objetivo: Investigar se a dor nas costas nas mulheres esta relacionada com a altura do salto do calçado e o peso e forma de transporte da mala de mão. Métodos: Estudo exploratório de corte transversal, realizado numa amostra de 130 mu-lheres em atividade laboral no Instituto Politécnico de Bragança. A recolha de dados foi efectuada mediante um instrumento de recolha de dados, constituído por questões relati-vas a dados sociodemográficos, dados antropométricos, calçado: altura e uso habitual, carteira: peso e modo de transporte, levante/transporte de cargas na atividade profissional, prática de exercício físico e por fim, caraterização da dor quanto à localização, intensi-dade e frequência no último ano e últimos trinta dias. Resultados: Estudou-se uma amostra de 130 mulheres e conclui-se que existe uma pre-valência de dor nas costas sentida no último ano de 85,4% e nos últimos trinta dias de 81,1%. A localização da dor mais comum foi na região lombar com 56,8% e de 58,9% no último ano e últimos trinta dias respectivamente. Das mulheres que sentiram dor no úl-timo ano, 40,5% referiu ter sentido dor todos os dias e 33,3% das inquiridas acusaram uma intensidade de dor de grau 5. Quanto a sentir dor nas costas nos últimos trinta dias, 50,5% referiu ter sentido dor todos os dias e 29,7% das inquiridas manifestam dor de grau 5. Conclusão: Verificou-se que a altura do salto do calçado e o peso, a forma e o transporte da mala de mão, não estão associados ao aparecimento da dor nas costas.

The occurrence of back pain is due to the bodily modifications that accom-pany individuals over the years. Among risk fators we found the biomechanical alteration of the spine caused by mechanical overload and incorrect posture. Objective: Investigate whether back pain in women is related to the high heels and the weight and shape of the handbag. Methods: This cross-sectional exploratory study was carried out on a sample of 130 women in work at the Polytechnic Institute of Bragança. Data collection was carried out by means of a data collection instrument, consisting of questions related to socio-demo-graphic data, anthropometric data, footwear: height and habitual use, portfolio: weight and mode of transport, lifting / transport of loads in the professional activity, practice of physical exercise and finally, characterization of the pain regarding the location, intensity and frequency in the last year and last thirty days. Results: A sample of 130 women was studied and it is concluded that there is a prevalence of back pain felt in the last year of 85.4% and in the last thirty days of 81.1%. The most common pain location was in the lumbar region with 56.8% and 58.9% in the last year and the last thirty days respectively. Of the women who felt pain in the last year, 40.5% reported having felt pain every day and 33.3% of the respondents accused a pain intensity of grade 5. As for feeling back pain in the last thirty days, 50.5 % reported experiencing pain every day and 29.7% of those surveyed showed grade 5 pain. Conclusions: It has been found that the high heels and the weight, shape and transport of the handbag are not associated with the appearance of back pain.

Quality of life, school backpack weight, and nonspecific low back pain in children and adolescents / Qualidade de vida, peso das mochilas escolares e lombalgia não específica em crianças e adolescentes

OBJECTIVES: To describe the degree of disability, anthropometric variables, quality of life (QoL), and school backpack weight in boys and girls aged 11-17 years. The differences in QoL between those who did or did not report low back pain (LBP) were also analyzed. METHODS: Eighty-six girls (13.9 ± 1.9 years of age) and 63 boys (13.7 ± 1.7 years of age) participated. LBP was assessed by questionnaire, and disability using the Roland-Morris Disability Questionnaire. QoL was assessed by the Pediatric Quality of Life Inventory (PedsQL). Multivariate analyses of variance and covariance were used to assess differences between groups. RESULTS: Girls reported higher disability than boys (p = 0.01), and lower QoL in the domains of physical (p < 0.001) and emotional functioning (p < 0.01), psychosocial health (p = 0.02) and physical health summary score (p < 0.001), and on the total PedsQL score (p < 0.01). School backpack weight was similar in both genders (p = 0.61) and in participants with and without LBP (p = 0.15). After adjustments, participants with LBP reported lower physical functioning (p < 0.01), influencing lower physical health summary score (p < 0.01). CONCLUSIONS: Girls had higher disability and lower QoL than boys in the domains of physical and emotional functioning, psychosocial health, and physical health summary scores, and on the total PedsQL score; however, similar school backpack weight was reported. Participants with LBP revealed lower physical functioning and physical health summary score, yet had similar school backpack weight to those without LBP. .

OBJETIVOS: Descrever o grau de incapacidade, as variáveis antropométricas, a qualidade de vida (QV) e o peso das mochilas escolares em meninos e meninas com 11-17 anos. Também são analisadas as diferenças na QV entre os que relataram ou não lombalgia (LBP). MÉTODOS: 86 meninas (13,9 ± 1,9 anos) e 63 meninos (13,7 ± 1,7 anos) participaram. A LBP foi avaliada por um questionário e a incapacidade pelo Questionário Roland-Morris. A QV foi avaliada pelo Questionário Pediátrico sobre Qualidade de Vida (PedsQL). As análises de variância e de covariância multivariadas foram usadas para avaliar as diferenças entre os grupos. RESULTADOS: As meninas relataram maior incapacidade do que os meninos (p = 0,01) e menor QV nos domínios de funcionamento físico (p < 0,001) e emocional (p < 0,01), no escore sumário de saúde psicossocial (p = 0,02) e saúde física (p < 0,001) e no escore total no PedsQL (p < 0,01). O peso das mochilas escolares era semelhante para ambos os sexos (p = 0,61) e para os participantes com e sem LBP (p = 0,15). Após ajustes, os participantes com LBP relataram menor funcionamento físico (p < 0,01), o que influenciou um menor escore sumário de saúde física (p < 0,01). CONCLUSÕES: As meninas tiveram maior incapacidade e menor QV do que os meninos nos domínios de funcionamento físico e emocional, nos escores sumários de saúde psicossocial e física e no escore total no PedsQL; contudo, foi relatado um peso semelhante das mochilas escolares. Os participantes com LBP revelaram menor funcionamento físico e escore sumário de saúde física, mesmo carregando mochilas escolares de mesmo peso do que aqueles sem LBP. .

Quality of life, school backpack weight, and nonspecific low back pain in children and adolescents.

OBJECTIVES: To describe the degree of disability, anthropometric variables, quality of life (QoL), and school backpack weight in boys and girls aged 11-17 years. The differences in QoL between those who did or did not report low back pain (LBP) were also analyzed. METHODS: Eighty-six girls (13.9 ± 1.9 years of age) and 63 boys (13.7 ± 1.7 years of age) participated. LBP was assessed by questionnaire, and disability using the Roland-Morris Disability Questionnaire. QoL was assessed by the Pediatric Quality of Life Inventory (PedsQL). Multivariate analyses of variance and covariance were used to assess differences between groups. RESULTS: Girls reported higher disability than boys (p = 0.01), and lower QoL in the domains of physical (p < 0.001) and emotional functioning (p < 0.01), psychosocial health (p = 0.02) and physical health summary score (p < 0.001), and on the total PedsQL score (p < 0.01). School backpack weight was similar in both genders (p = 0.61) and in participants with and without LBP (p = 0.15). After adjustments, participants with LBP reported lower physical functioning (p < 0.01), influencing lower physical health summary score (p < 0.01). CONCLUSIONS: Girls had higher disability and lower QoL than boys in the domains of physical and emotional functioning, psychosocial health, and physical health summary scores, and on the total PedsQL score; however, similar school backpack weight was reported. Participants with LBP revealed lower physical functioning and physical health summary score, yet had similar school backpack weight to those without LBP.

Alteraciones de columna vertebral y tipos de bolsas escolares en estudiantes de 14 a 16 años en el Colegio Saco Oliveros de los Olivos, diciembre 2013 / Alterations of spinal column and types of school bags in students of 14-16 years in College Saco Oliveros of Los Olivos, December 2013

Objetivo: Determinar las alteraciones de columna vertebral en relación al tipo de bolsa escolar. Diseño: Estudio observacional descriptivo de tipo transversal. Métodos: El estudio se llevó a cabo en el Colegio "Saco Oliveros" de Los Olivos del Departamento de Lima. La población estudiada fue de 107 alumnos entre 14 a 16 años de edad, donde el 56 por ciento de los estudiantes usaban mochila. Los datos fueron recolectados mediante una ficha de evaluación, el cual estuvo dividido en datos del estudiante (edad, sexo); bolsa escolar (tipo, forma de uso, peso) y la evaluación postural. Se realizó el análisis estadístico mediante el programa Excel 2010 se agrupó en tablas de contingencia y se usó la prueba de intervalo de confianza para hallar la significancia estadística. Resultados: En el estudio se encontró que había mayor frecuencia de escoliosis en los escolares que usan morral (100 por ciento) en comparación a los que usan mochila (93.3 por ciento), el sexo masculino presenta mayor frecuencia de hipercifosis (27.7) a diferencia del sexo femenino (6.7 por ciento), en los escolares de 14 años de edad los que usan mochila presentaron mayor frecuencia de hipercifosis (28.6 por ciento) en contraste con los escolares que usan morral (0 por ciento), los escolares que llevan la mochila en un solo hombro presentaron mayor frecuencia de escoliosis (100 por ciento) a diferencia de los que llevan en los dos hombros (89.5 por ciento), los escolares que llevan la mochila en los dos hombros presentan mayor frecuencia de hiperlordosis (63.2 por ciento) en comparación en los que lo llevan en un solo hombro (31.2 por ciento) y por último los escolares que cargan un peso de 2,5 a 5 kilos hay mayor frecuencia de escoliosis en los escolares que usan el morral (100 por ciento) a diferencia de los que usan la mochila (90.7 por ciento). Conclusión: El morral es un factor que contribuye a una mayor frecuencia de escoliosis, y la mochila influye en las alteraciones de columna...

Objective: Determine spine alterations in relation to type of school bag. Design: Study Observational, descriptive, cross-sectional. Methods: The study was conducted in the college "Saco Oliveros" in the Los Olivos in Lima department. The study population was 107 students between 14-16 years of age, where 56 per cent of students used backpack. The data were collected through an assessment sheet, which was divided into student data (age, sex); school bag (type, mode of use, weight) and postural assessment. Statistical analysis was performed using Excel 2010 program is grouped into contingency tables and test confidence interval was used to find statistical significance. Results: the study found that there was a higher frequency of scoliosis in school using briefcase (100 per cent) compared to those using backpack (93.3 per cent), males more frequently presents hyperkyphosis (27.7) difference the female (6.7 per cent) in school children who were 14 years using backpack presented more frequent hyperkyphosis (28.6 per cent) in contrast to school wearing briefcase (0 per cent) carrying school backpack on one shoulder showed greater frequency scoliosis (100 per cent) unlike those who carry on both shoulders (89.5 per cent), school carrying backpack on both shoulders have a higher frequency of hyperlordosis (63.2 per cent) compared to those who carry in one shoulder (31.2 per cent) and finally the students who carry a weight of 2.5 to 5 kilos is no greater frequency of scoliosis in school wearing briefcase (100 per cent) as opposed to using the backpack (90.7 per cent). Conclusion: The briefcase is a contributing factor to increased frequency of scoliosis, and backpack influences spine alterations depending on how you take and how much weight is loaded into

Transporte do material escolar por escolares da rede municipal de ensino fundamental de Porto Alegre - RS / School supplies transportation for municipal elementary school children in Porto Alegre - RS

Transportar carga é uma ação realizada diariamente por todos os escolares. Mochilas, bolsas, pastas são as formas mais comuns observadas. Alguns desses equipamentos favorecem a manutenção de uma postura adequada, especialmente da coluna vertebral, outros, nem tanto. Além do meio como o material é transportado, seu peso (≥10% do peso corporal) é uma variável que pode interferir no deslocamento do centro de gravidade e na flexão do tronco. A associação de flexão da coluna e transporte de carga pode ser um fator desencadeante de patologias da coluna vertebral. O objetivo deste estudo foi verificar a forma como os escolares da Rede Municipal de Ensino Fundamental de Porto Alegre transportam o material escolar, bem como o peso transportado. Este é um estudo descritivo-exploratório transversal. A amostra foi composta de forma aleatória por 430 escolares, estratificados (faixa etária e sexo) pelas quatro regiões administrativas da cidade. Os participantes foram fotografados com o seu material escolar e foram pesados com e sem esses equipamentos. A diferença de peso serviu para identificar o peso transportado. Observou-se que os participantes utilizam majoritariamente a mochila nas costas com apoio sobre os dois ombros para a realização dessa tarefa, não havendo diferença entre meninos e meninas ou entre as faixas etárias. Esses resultados são equivalentes aos encontrados em estudos realizados com outras populações. Foi observado também que o peso médio do material escolar foi de 5,46% do peso corporal, sendo que 8,5% dos participantes transportavam mais de 10% do peso corporal. Esses resultados são inferiores aos observados em outros estudos com outros grupos. Apesar de valores inferiores aos dados internacionais, ações no âmbito da comunidade escolar devem ser realizadas com o objetivo de propor alternativas para diminuir a prevalência de escolares transportando uma carga que pode ser nociva a sua saúde.

Carrying a load is action taken daily by all students. Backpacks, purses, briefcases are the most common forms observed. Some of these items help to maintain a proper posture, especially the spine, others less so. In addition, its weight (≥ 10% of body weight) is a variable that can interfere with the displacement of the center of gravity and trunk flexion. The association of spinal flexion and heavy load can be a triggering factor for diseases of the spine. The objective of this study was to determine how the students of the Municipal Elementary School in Porto Alegre carry school supplies, as well as the weight carried. This is a cross-sectional descriptive exploratory study. The sample consisted of 430 participants randomly stratified (age and sex) by four administrative regions of the city. The participants were photographed with their school supplies and were weighed with and without the equipment. The weight difference was used to identify the weight carried. It was observed that the participants mainly use the backpack with support on both shoulders to this task, with no difference between boys and girls or between age groups. These results are equivalent to those found in studies of other populations. It was also observed that the average weight of school supplies was 5.46% of body weight, and 8.5% of participants carried over 10% of body weight. These results are lower than those observed in other studies with other groups. Eventhough these results are lower than international data reported, actions within the school community should be conducted in order to propose alternatives to reduce the prevalence of students carrying a load that can be harmful to your health.

Técnicas de controle de qualidade utilizadas na criaçäo de tilápia do nilo (Oreochromis niloticus) em caixas de amianto / Quality control techniques used in the breeding of nile tilapia (Oreochromis niloticus) in amianthus box

Este trabalho apresenta os resultados do monitoramento realizado durante 330 dias na Estaçäo de Piscicultura da Universidade Estadual de Londrina - UEL, com o objetivo de utilizar técnicas de controle de qualidade para atingir maior produtividade de tilápias. Foram utilizados 240 alevinos de tilápia do Nilo (Oreochromis niloticus), distribuídos num delineamento inteiramente casualizado. Os valores da temperatura média mensal revelaram estar "fora de controle estatístico" e mostraram através da aplicaçäo dos índices de capacidade (Cp e Cpk) que 39,74 por cento estäo abaixo do limite inferior de especificaçäo (LIE). A análise dos resultados obtidos, através da aplicaçäo das técnicas de Pareto e Problema da Mochila, evidenciaram a soluçäo ótima para resolver os problemas de Saprolenea sp-2 e Laerner sp-4 com a funçäo objetivo Z* maximizada