ABSTRACT Introduction: Preventing teenage pregnancy and pregnancy-related mortality is critical to achieving positive health outcomes throughout life and it is essential to achieving the Sustainable Development Goals. Objective: To describe obstetric mortality and its causes in adolescents in Cuba in 2007 to 2020. Methods: A descriptive study of chronological series was carried out. The universe was the 60 maternal deaths in adolescents in 2007 to 2020 in Cuba. The variable maternal death due to obstetric causes was used according to the international classification of diseases. The maternal mortality ratio, average, maximum and minimum values were calculated. Correlation analysis was carried out with the Box Ljung statistic to test for autocorrelation. P ≤ 0.05 was considered significant. Results: On average, four maternal deaths occurred annually with the highest load in 2015 (16.7%). The mean mortality ratio was 23.7 per 105 live births. The highest corresponded to 2015 (56.0) and the lowest was in 2012 with no deaths. The correlogram did not show a trend or correlation and the probabilities associated with Box Ljung were not significant (p > 0.05). The highest values were in postpartum complications (5.1 per 105 live births), followed by abortions. Conclusions: The excess risk of maternal mortality in adolescents in Cuba is not negligible and its main causes are puerperal sepsis and medical abortions.

RESUMEN Introducción: La prevención del embarazo entre las adolescentes y la mortalidad relacionada con este embarazo son fundamentales para lograr resultados positivos en la salud a lo largo de la vida y son imprescindibles para alcanzar los Objetivos de Desarrollo Sostenible. Objetivo: Describir la mortalidad obstétrica y sus causas en adolescentes en Cuba entre 2007-2020. Métodos: Se realizó un estudio descriptivo de series cronológicas. El universo fueron las 60 muertes maternas en adolescentes entre 2007-2020 en Cuba. Se utilizó la variable muerte materna por causas obstétricas según la clasificación internacional de enfermedades. Se calcularon la razón de mortalidad materna, promedio, valores máximos y mínimos. Se efectuó análisis de correlación con el estadístico Box Ljung para probar autocorrelación. Se consideró significativo p ≤ 0,05. Resultados: Como promedio ocurrieron cuatro muertes maternas anuales con mayor peso en 2015 (16,7 %). La media de la razón de mortalidad fue de 23,7 por 105 nacidos vivos. La más elevada correspondió al año 2015 (56,0) y el mínimo fue en 2012 sin decesos. El correlograma no evidenció tendencia ni correlación y las probabilidades asociadas a Box Ljung no fueron significativas (p > 0,05). Los valores más altos fueron en las complicaciones del puerperio (5,1 por 105 nacidos vivos), seguida de abortos Conclusiones: El exceso de riesgo de mortalidad materna en adolescentes en Cuba no resulta despreciable y sus principales causas son la sepsis puerperal y los abortos médicos.

RESUMEN El propósito de este trabajo es desarrollar soluciones técnicas que permitan proporcionar los parámetros especificados de la precisión de la forma de las piezas en la sección transversal durante el procesamiento en una máquina CNC. Se realizaron estudios experimentales en un torno de tornillo. Se usó una señal acústica en el rango de 6 a 12 kHz como señal de diagnóstico para evaluar el desgaste de la herramienta de corte, ya que durante los estudios preliminares se descubrió que este rango es más sensible a los cambios en los modos de procesamiento. Los estudios se realizaron a diferentes valores de desgaste de la herramienta de corte (estimado por el ancho del chaflán de desgaste). Se ha desarrollado un modelo neuro-difuso para estimar la vida de una herramienta de corte. El uso de modelos de esta clase permite ajustarse a condiciones específicas (máquina, herramienta) y evaluar correctamente la vida útil de la herramienta. El error del modelo para la muestra de prueba no supera el 10%. Los resultados de la prueba mostraron que el uso de las soluciones propuestas permite aumentar la precisión de la fabricación de piezas de la válvula de cierre en un 20-30%.

ABSTRACT This work aims to develop technical solutions that allow providing the specified parameters of the accuracy of the shape of parts in the cross-section during processing on a CNC machine. Experimental studies were performed on a screw-cutting lathe. An acoustic signal in the range from 6 to 12 kHz was used as a diagnostic sign to assess the wear of the cutting tool, since during preliminary studies, it was found that this range is most sensitive to changes in processing modes. Studies were performed at different values of wear of the cutting tool (estimated by the width of the wear chamfer). For estimating the life of a cutting tool, a neuro-fuzzy model has been developed. Using models of this class allows adjusting to specific conditions (machine, tool), and correctly evaluating the tool life. The model error for the test sample does not exceed 10%. The test results showed that using the proposed solutions makes it possible to increase the accuracy of the manufacturing of shut-off valve parts by 20-30%.

Abstract INTRODUCTION The recent emergence and rapid spread of Zika and Chikungunya fevers in Brazil, occurring simultaneously to a Dengue fever epidemic, together represent major challenges to public health authorities. This study aimed to identify and compare the 2015-2016 spatial diffusion pattern of Zika, Chikungunya, and Dengue epidemics in Salvador-Bahia. METHODS We used two study designs comprising a cross-sectional-to-point pattern and an ecological analysis of lattice data. Residential addresses involving notified cases were geocoded. We used four spatial diffusion analysis techniques: (i) visual inspection of the sequential kernel and choropleth map, (ii) spatial correlogram analysis, (iii) spatial local autocorrelation (LISA) changes analysis and, (iv) nearest neighbor index (NNI) modeling. RESULTS Kernel and choropleth maps indicated that arboviruses spread to neighboring areas near the first reported cases and occupied these new areas, suggesting a diffusion expansion pattern. A greater case density occurred in central and western areas. In 2015 and 2016, the NNI best-fit model had an S-curve compatible with an expansion pattern for Zika (R2 = 0.94; 0.95), Chikungunya (R2 = 0.99; 0.98) and Dengue (R2 = 0.93; 0.99) epidemics, respectively. Spatial correlograms indicated a decline in spatial lag autocorrelations for the three diseases (expansion pattern). Significant LISA changes suggested different diffusion patterns, although a small number of changes were detected. CONCLUSIONS These findings indicate diffusion expansion, a unique spatial diffusion pattern of Zika, Chikungunya, and Dengue epidemics in Salvador-Bahia, namely. Knowing how and where arboviruses spread in Salvador-Bahia can help improve subsequent specific epidemic control interventions.

ABSTRACT: There is an increasing interest in the application of geophysical surveys to assess the soil water content (SWC) variation in both spatial and temporal scales. In this work, a geophysical survey was carried out at an experimental farm in dry and wet conditions. We determined the SWC data measured with the gravimetric method, apparent electrical conductivity by electromagnetic induction (EMI) and amplitude of Ground Penetrating Radar (GPR) data at different frequencies. Geophysical sensors are an efficient tool for soil mapping at high resolution; however; there is a need to improve the knowledge on their capabilities and limitations under field conditions, especially for GPR. The geophysical survey provides an example of the application of these techniques to evaluate the spatial variability of SWC in two different water conditions. The contribution of geophysical data in understanding the spatial variability of SWC was investigated applying both the traditional analysis and spatial techniques. The results indicated that the geophysical data captured the spatial variation of SWC in non-invasively way especially in dry condition. However, they also showed the complex interplay between factors controlling SWC and geophysical responses and the drawbacks of geophysical sensors under inhomogeneous water conditions. Our findings also highlighted that EMI survey provides the potential to map the SWC variability within a relatively short time. The results obtained in this research are important from the agronomical viewpoint, since they allow increasing efficiency of irrigation practices, which is important in times characterized by climate change.

In mineral resource evaluations, geostatistical methods known as global change of support allow prediction of the theoretical histogram and gradetonnage curves prior to interpolations or simulations of grades. Two methods commonly used by professionals to guide the choice of interpolation parameters and assess results are the discrete Gaussian model (DGM) and the indirect lognormal correction (IndLog). These models rely upon an estimate of the dispersion variance of the blocks, which is derived by numerical integration of the variogram model over a discretized block. Due to difficulties in obtaining well-formed traditional experimental variograms (especially in the presence of outliers and limited clustered data), many professionals prefer to use 'normalized' variograms such as correlogram (non-ergodic variogram), pairwise-relative, or variogram of the normal score transform. A series of simulations with different grade distributions and variogram models are used to assess the performances and robustness of the various variogram estimators with respect to the DGM and IndLog global change of support. Our results show that the traditional variogram, the correlogram, and normal score variogram have better performances, compared to pairwise, for both DGM and IndLog. Moreover, DGM provided better results than IndLog for the grade distributions that are not strictly lognormal. These findings provide valuable guides for geostatistics practitioners.

Abstract: A new geotechnical zoning map for the subsoil of Mexico Valley is presented. This proposal is based on a Geographic Information System for Geotechnical Borings (GIS-GB), which contains over 10000 soil profiles. In addition to the geotechnical information, available topographic and geological data on the studied area were taken into account. Geostatistical techniques were used to assess the spatial distribution of the thickness of the lacustrine clay deposits within the area down to the so-called deep deposits. As a result, a contour map was obtained that was used to update the current geotechnical zoning map for Mexico Valley. It has been proposed to include this new map into the Building Code for the Federal District (Mexico City).

Resumen: Se presenta una nueva zonificación geotécnica para el subsuelo del valle de México. Esta propuesta se basa en un Sistema de Información Geográfica para sondeos geotécnicos (SIG-GB), que almacena más de 10000 perfiles de suelo. Además de la información geotécnica, se tomaron en cuenta los datos topográficos y geológicos disponibles relativos a la zona estudiada. Se aplicaron técnicas geoestadísticas para evaluar la distribución espacial del espesor de los depósitos arcillosos del área hasta los llamados depósitos profundos. Como resultado se obtuvo un mapa de contornos que se utilizó para actualizar la zonificación geotécnica para el Valle de México. Se ha propuesto que este nuevo mapa de zonificación geotécnica se incorpore en el nuevo Reglamento de Construcciones para el Distrito Federal.

In order to understand the processes that trigger landslides and the factors that may influence their generation such as geomorphology and climatology, this paper presents a new database of landslide processes compiledfor Bogotá, constructedfrom technical reports elaborated by the Instituto Distrital de Gestión del Riesgo y Cambio Climático IDIGER (formerly known as FOPAE). This database includes 2208 landslide events that occurred between 1996 and 2013. Because of the many features described in the technical reports, it was necessary to categorize in a systematic way variables like soil type, type of movement, possible cause that triggered the event, ground cover, average inclination of the slope, and the volume of sliding material, in order to condense the largestpossible amount of information. The database allows to infer relationships between precipitation and the occurrence of landslides in Bogotá. Analysis of the database shows a strong relationship between monthly rainfall and monthly amount of landslides, marked by a bimodal regime with the maximum recorded occurrence of slides between April-May and November-December. The time series of slides shows a hint of relationship with the Oceanic Niño Index ONI series, since for some Niña periods (more rain) the amount of recorded landslides increases. In addition, the correlogram of the time series of landslides is calculated, showing that the occurrence of landslide events may be associated with the reactivation of events that previously took place (six months in the past).

Con el objetivo de tener mayores insumos para mejorar el entendimiento del problema de detonación de los procesos de remoción en masa y los factores que influyen sobre éstos, el presente artículo introduce una base de datos de procesos de remoción en masa para Bogotá, construida a partir de informes técnicos elaborados por el Instituto Distrital de Gestión del Riesgo y Cambio Climático IDIGER (antiguo FOPAE) tras la ocurrencia de cada evento de remoción de masa en la ciudad. Esta base de datos incluye 2208 eventos de movimientos en masa ocurridos en el perímetro urbano de Bogotá entre 1996y 2013. Debido a las múltiples características reportadas en los informes, se recopilaron de forma sistemática variables como tipo de suelo, tipo de movimiento, posible causa detonante del evento, cobertura del suelo, pendiente promedio del lugar de la inestabilidad y el volumen de material deslizado, con el fin de condensar la mayor cantidad de información posible. Se exploró la relación entre el régimen de lluvias de Bogotá y la ocurrencia de movimientos en masa, encontrando una fuerte interrelación entre estas dos variables, marcado por un régimen bimodal con los máximos para los meses de abril-mayo y noviembre-diciembre. La serie histórica de movimientos en masa muestra una tendencia en la relación con el Indice Oceánico del Niño ONI, con algunas observaciones especiales para algunos años Niña en cuanto al incremento de ocurrencia de procesos de remoción en masa. Se elabora el autocorrelograma de la serie histórica de deslizamientos, con lo que se puede inferir que los eventos de remoción en masa están asociados a nivel temporal con la reactivación de procesos ocurridos 6 meses antes, lo que ratifica la relación lluvia deslizamiento de carácter bimodal.

An algorithm for extracting tachograms for Heart Rate Variability (HRV) analysis on the basis of Photoplethysmographic (PPG) signals (instead of electro cardiograms) has been proposed. The main feature of this proposal is to detect peaks from correlograms between a pattern waveform and a sliding time window in the PPG signal. Analysis was carried out with a set of two groups of patients (young and elderly).HRV variables were estimated using the publicly available Kubios HRV package. Results showed that both the sympathetic component of the autonomous nervous system (assessed by LF/HF) and the cardiovascular complexity (assessed by correlation dimension) are reduced with age. These results are supported by literature and may be taken as a support for the validity of the proposed algorithm. Since oximeters for getting PPG signals are affordable even in poor settings, this allows extending autonomic nervous system studies into remote areas of developing countries.

Se propone un algoritmo para obtener tacogramas con la finalidad de realizar estudios de variabilidad de la frecuencia cardiaca, partiendo de registros de señales fotopletismográficas (PPG). La principal peculiaridad de esta propuesta lo es la detección de los picos en las ondas de la señal PPG a partir de un correlograma obtenido como una secuencia de correlaciones entre una onda patrón y una ventana deslizante de la señal PPG. Se realizó un análisis de variabilidad de frecuencia cardiaca sobre dos grupos de pacientes (jóvenes y de avanzada edad). Las variables de variabilidad de frecuencia cardiaca seleccionadas se obtuvieron a partir del programa "Kubios HRV", de acceso público y gratuito. Los resultados mostraron que tanto el componente simpático del Sistema Nervioso Autónomo (evaluado a través de la variable LF/HF) como la complejidad cardiovascular (evaluada a través de la dimensión de correlación) disminuyeron con la edad. Estos resultados encuentran apoyo en datos de la literatura que apoyan así la validez del algoritmo propuesto. Por cuanto el oxímetro utilizado para obtener las señales PPG está al alcance de instituciones primarias de salud se hace posible de esta manera extender estudios del sistema nervioso autónomo hacia áreas remotas de países en desarrollo.

RESUMO Este trabalho investigou atributos de assembleias (composição, abundância, riqueza, diversidade e equitabilidade) e os gêneros mais representativos de Odonata, Anisoptera nos riachos Água Boa e Perobão, bacia do rio Iguatemi, MS, Brasil. Os riachos são de primeira ordem, apresentam extensão similar e são impactados pela remoção da mata ripária e assoreamento. As amostragens foram realizadas trimestralmente de março a dezembro/2008 nos trechos superior, intermediário e inferior de ambos os riachos. O teste de Mantel foi utilizado para verificar a influência da autocorrelação espacial sobre a composição de Odonata. Variações espaciais na composição foram sumarizadas através da Análise de Coordenadas Principais (PCoA) utilizando-se os resíduos do teste de Mantel. Os efeitos da correlação espacial na riqueza e abundância foram investigados através do correlograma espacial dos coeficientes do I de Moran. Para identificar os gêneros mais representativos em cada riacho foi utilizado o Método do Valor Indicador. As variações espaciais dos atributos das assembleias foram avaliadas por meio de análises de variância de modelos nulos. Foram coletados 500 indivíduos imaturos distribuídos em 23 gêneros e três famílias. Dentre os atributos analisados, apenas a composição e abundância apresentaram diferenças espaciais significativas, sendo o maior valor médio do último atributo registrado no riacho Perobão. Miathyria e Zenithoptera foram os gêneros indicadores do riacho Água Boa e Erythrodiplax, Libellula, Macrothemis, Progomphus e Tramea do Perobão.

ABSTRACT This study investigated the assemblages attributes (composition, abundance, richness, diversity and evenness) and the most representative genera of Odonata, Anisoptera at Água Boa and Perobão Streams, Iguatemi River basin, Brazil. Both are first order streams with similar length that are impacted by riparian forest removal and silting. Quarterly samplings were conducted from March to December 2008 in the upper, intermediate and lower stretch of each stream. The Mantel test was used to check the influence of spatial autocorrelation on the Odonata composition. Spatial variations in the composition were summarized by the Principal Coordinates Analysis (PCoA) using Mantel test residuals. The effects of spatial correlation on richness and abundance were investigated by the spatial correlogram of Moranʼs I coefficients. The most representative genera in each stream were identified by the Indicator Value Method. The spatial variations in the attributes of the assemblages were assessed using analysis of variance of null models. We collected 500 immature individuals of 23 genera and three families. Among the attributes analyzed only the composition and abundance showed significant spatial differences, with the highest mean abundance found in the Perobão Stream. Miathyria and Zenithoptera were the indicator genera of the Água Boa Stream and Erythrodiplax, Libellula, Macrothemis, Progomphus and Tramea were the indicator genera of the Perobão Stream.

The Box-Jenkins methodology was used to select an ARMA model to forecast beef production in Baja California, Mexico. The series of bovine carcasses processed monthly in the state's slaughterhouses between 2003 and 2010 was used. Because the inspection of the series graph and correlogram did not determine a stationary behavior, an augmented Dickey-Fuller test was performed and it was found that the series was stationary. As a result of identification procedure, an AR (1) and an ARMA (2, 1) models were selected and estimated using ordinary least squares. The estimated models were compared using the significance of the regression coefficient and the Akaike information and Schwartz Bayesian criteria. A diagnostic check was done examining the goodness of fit of the models by plotting the residuals; the Q statistic was used to test for autocorrelation. Because the results were similar, a predictive efficacy evaluation of two models was carried out using a group of forecast error statistics. The result of these tests indicated that the ARMA (2,1) had a better forecasting capability, this was supported by plotting together a forecasted series with the actual series and the out-of sample prediction for January of 2011. The results support the use of ARMA models to obtain reliable short term forecasts of beef production in Baja California.

Con el fin de pronosticar la producción de carne de bovino en Baja California, México, se utilizó el método de Box-Jenkins para seleccionar un modelo autorregresivo de promedios móviles (ARMA). Para ello se usó la información de canales de bovinos procesadas mensualmente en los rastros del estado durante el periodo de 2003 a 2010. Debido a que la inspección de la gráfica de la serie y el correlograma de la misma no permitieron establecer la estacionariedad, se aplicó la prueba de Dickey-Fuller aumentada, en la que se encontró que la serie era estacionaria. Como resultado del procedimiento de identificación se seleccionaron los modelos AR(1) y ARMA (2,1), los cuales se estimaron utilizando mínimos cuadrados; se compararon ambos modelos con base en la significancia de sus coeficientes de regresión y los estadísticos de Akaike y Schwartz. Se llevó a cabo una evaluación diagnóstica para revisar la bondad de ajuste de los modelos mediante la gráfica de los residuales; el valor de los estadísticos Q se utilizó para determinar la ausencia de autocorrelación en los modelos propuestos. Debido a que los resultados fueron similares, se llevó a cabo una evaluación de la eficiencia predictiva de ambos modelos utilizando una serie de estadísticos. Los resultados de estas pruebas indicaron que el modelo ARMA (2,1) presentaba una mejor capacidad predictiva, que fue corroborada mediante una gráfica conjunta de la serie actual y la pronosticada, y una predicción para el mes de enero de 2011. Los resultados respaldan el uso de modelos ARMA para obtener, a corto plazo, predicciones de la producción de carne en Baja California.

A descrição dos padrões espaciais é importante para se elaborar hipóteses sobre a dinâmica de populações vegetais. Nosso objetivo foi verificar diferenças nos padrões espaciais de classes de tamanho de Q. grandiflora dentro e entre fragmentos com diferentes fisionomias de cerrado. Para isso descrevemos e comparamos os padrões espaciais do número de plantas por subparcela (5 x 5 m) em seis parcelas de 0,5 ha em quatro fragmentos. Descrevemos os padrões para duas classes de tamanho utilizando correlogramas com o índice I de Moran e testamos associações espaciais entre classes pelo teste de Mantel parcial. A abundância variou de 18 a 319 plantas 0,5 ha-1. Plantas maiores (altura > 1,5 m) tiveram padrões agregados em todos os casos, com números e tamanhos das escalas de agregação variando independentemente da fisionomia. Somente em três parcelas foi possível descrever os padrões espaciais de plantas menores, onde foram aleatórios. Nesses casos, houve duas associações significativas positivas entre classes e uma não significativa. As diferenças de abundância e padrão espacial entre parcelas foram tão grandes no mesmo fragmento quanto entre fragmentos, indicando que a estrutura espacial de Q. grandiflora é imprevisível com base na fisionomia. A transição aleatório-agregado e a associação espacial entre classes indicam que mortalidade dependente de densidade não parece ser importante na dinâmica de Q. grandiflora, sendo a estrutura espacial dos locais adequados ao recrutamento para maturidade um possível fator mais importante.

The study of spatial patterns is a helpful approach to formulating hypotheses about plant population dynamics. Our aim was to search for variation in spatial patterns of Q. grandiflora height classes at different scales within and among fragments of different cerrado physiognomies. Spatial patterns of the number of plants in subplots (5 x 5 m) were described and compared among six 0.5-ha plots placed in four fragments. We performed Moran's I correlogram analysis to describe spatial patterns and tested spatial correlations of height classes by partial Mantel tests. We found 18 to 319 plants 0.5 ha-1. Larger plants (height >1.5 m) had a clumped pattern in all plots, varying in numbers and magnitudes of scales independently of the physiognomy. Correlogram analysis for smaller plants was possible in only three plots, where patterns were random. In two of these cases there was significant positive correlation of size classes but in the third it was not significant. Abundance and spatial patterns were as different within the same fragment as in different ones. These results show that Q. grandiflora spatial patterns cannot be predicted based on overall characteristics of cerrado physiognomy. The random-to-clumped transition with size and the spatial association of classes suggest that density dependent mortality does not seem to be an important driver of Q. grandiflora dynamics, and that spatial structure of suitable sites for recruitment to maturity may be more important.

Seasonal variation is a component of time series identified in a number of health events and describied in morbidity, mortality among others. Identification of seasonality, the analysis of its variability and detection of its period are key elements to discover deviations from the regular behaviour of health phenomena, which allows early alert in the face of possible outbreaks or epidemics and adequate health surveillance. Graphic methods are useful tools to examine seasonality since they provide a more rapid general overview than the simple direct data observation. This paper showed the results of the application of various graphs to detect and analyze seasonality, that is, the box and moustache graphs, the correlogram or autocorrelation function graph and the periodgram that is the main detecting tool of the significant spectral analysis frequencies. A descriptive study was performed to scrutinize seasonal variation in monthly series of infant mortality (rate per 1000 live births), births(absolute number), Aedes Aegypti infestation (absolute number of foci) in Cuba from 1998 to 2005. These three examined health events exhibited manifest seasonality with different variability degrees and similar periods. The graphs were advantageous for health surveillance since they offered an improved visual representation and demonstrated more clearly the short-term variation within the times series

La variación estacional es una componente de las series temporales identificada en numerosos eventos de salud. Se ha descrito en la morbilidad, la mortalidad, entre otros eventos. La identificación de la estacionalidad, el análisis de su variabilidad y la detección de su período son elementos cardinales para la identificación oportuna de desviaciones del comportamiento habitual de fenómenos de salud que permiten la alerta temprana ante la existencia de posibles brotes o epidemias y la realización de una adecuada vigilancia en salud. Los métodos gráficos son herramientas útiles para el estudio de la estacionalidad pues ofrecen una visión de conjunto más rápidamente perceptible que la simple observación directa de los datos. En este trabajo se muestran los resultados de la aplicación de varios gráficos para identificar y analizar la estacionalidad: el gráfico de cajas y bigotes, el correlograma o gráfico de las funciones de autocorrelación y el periodograma, principal herramienta para la identificación de frecuencias significativas del análisis espectral. Se realizó un estudio descriptivo donde se analizó la variación estacional en las series mensuales de la mortalidad infantil (tasa por 1 000 nacidos vivos), nacimientos (número absoluto), infestación por Aedes aegypti (número absoluto de focos) en Cuba, del período 1998-2005. Los tres eventos de salud analizados presentaron una estacionalidad manifiesta, con diferentes grados de variabilidad y períodos similares. Los gráficos resultaron útiles para la vigilancia pues proporcionaron una representación visual mejorada y mostraron de manera más clara la variación a corto plazo que se produjo dentro de la serie temporal

Seasonal variation is a component of time series identified in a number of health events and describied in morbidity, mortality among others. Identification of seasonality, the analysis of its variability and detection of its period are key elements to discover deviations from the regular behaviour of health phenomena, which allows early alert in the face of possible outbreaks or epidemics and adequate health surveillance. Graphic methods are useful tools to examine seasonality since they provide a more rapid general overview than the simple direct data observation. This paper showed the results of the application of various graphs to detect and analyze seasonality, that is, the box and moustache graphs, the correlogram or autocorrelation function graph and the periodgram that is the main detecting tool of the significant spectral analysis frequencies. A descriptive study was performed to scrutinize seasonal variation in monthly series of infant mortality (rate per 1000 live births), births(absolute number), Aedes Aegypti infestation (absolute number of foci) in Cuba from 1998 to 2005. These three examined health events exhibited manifest seasonality with different variability degrees and similar periods. The graphs were advantageous for health surveillance since they offered an improved visual representation and demonstrated more clearly the short-term variation within the times series

La variación estacional es una componente de las series temporales identificada en numerosos eventos de salud. Se ha descrito en la morbilidad, la mortalidad, entre otros eventos. La identificación de la estacionalidad, el análisis de su variabilidad y la detección de su período son elementos cardinales para la identificación oportuna de desviaciones del comportamiento habitual de fenómenos de salud que permiten la alerta temprana ante la existencia de posibles brotes o epidemias y la realización de una adecuada vigilancia en salud. Los métodos gráficos son herramientas útiles para el estudio de la estacionalidad pues ofrecen una visión de conjunto más rápidamente perceptible que la simple observación directa de los datos. En este trabajo se muestran los resultados de la aplicación de varios gráficos para identificar y analizar la estacionalidad: el gráfico de cajas y bigotes, el correlograma o gráfico de las funciones de autocorrelación y el periodograma, principal herramienta para la identificación de frecuencias significativas del análisis espectral. Se realizó un estudio descriptivo donde se analizó la variación estacional en las series mensuales de la mortalidad infantil (tasa por 1 000 nacidos vivos), nacimientos (número absoluto), infestación por Aedes aegypti (número absoluto de focos) en Cuba, del período 1998-2005. Los tres eventos de salud analizados presentaron una estacionalidad manifiesta, con diferentes grados de variabilidad y períodos similares. Los gráficos resultaron útiles para la vigilancia pues proporcionaron una representación visual mejorada y mostraron de manera más clara la variación a corto plazo que se produjo dentro de la serie temporal.

O presente estudo avalia a sazonalidade da ascensão de peixes na escada experimental localizada junto à barragem da hidrelétrica de Itaipu e as relações com a reprodução, temperatura, nível do rio e suas vazões. As amostragens de peixes e de fatores abióticos foram obtidas de fevereiro de 1995 a janeiro de 1997, em dois tanques de descanso, aqui denominados Caixas, sendo o primeiro, Caixa A, localizado na altura de 10 m da cota média do rio Paraná, e o segundo, Caixa B, ao final da escada, a 27 m de altura. Modelos autoregressivos foram empregados com o objetivo de remover a dependência temporal entre as observações. Posteriormente, os resíduos dos modelos foram utilizados para relacionar, através do coeficiente de correlação de Pearson, as densidades de peixes com as variáveis ambientais. Padrões claros de sazonalidade foram observados para a variável temperatura. As variáveis cota, vazão turbinada e vazão vertida, embora não tenham apresentado dinâmicas sazonais claras, foram temporalmente dependentes, tendo em vista que os coeficientes de autocorrelação, para diferentes k, foram significativos. Na amostragem de peixes de maior porte foram registradas 23 espécies ao longo dos dois anos de estudo, sendo que a maior parte dos indivíduos não se encontrava em reprodução e cerca de 90% dos indivíduos amostrados pertenciam a apenas seis espécies. A variabilidade temporal da abundância total, considerando o conjunto das espécies, indicou um padrão de variação sazonal, permitindo evidenciar que os maiores valores de abundância foram observados sistematicamente nos meses de outubro a fevereiro (75%) e na caixa A (61% dos 1343 indivíduos amostrados). Os menores valores foram registrados nos meses de inverno. O correlograma da densidade total confirma essa tendência. Nas amostragens destinadas às espécies de pequeno porte, foram registradas seis espécies, todas presentes em ambas as caixas, sendo mais freqüentes na primeira (64%). Entre essas espécies, Bryconamericus stramineus contribuiu com 99% do total amostrado. A variabilidade temporal da abundância total das espécies de pequeno porte indicou um padrão distinto de variação sazonal entre dois períodos anuais analisados.

We evaluated the seasonality of the ascent of fish in an experimental ladder located close to Itaipu Dam, and its relationships to reproduction, temperature, river level and discharge. Samplings of fish and measurements of abiotic factors were performed from February, 1995 through January, 1997, in two resting pools of the ladder. Pool A was located 10 m above the mean level of the Paraná River; Pool B was located at the upper end of the ladder, at a height of 27 m. Autoregressive models were used to remove the temporal dependence between observations. Residuals of the models were used to relate, using Pearson's correlation coefficient, the densities of fish to the environmental variables. Clear patterns of seasonality were observed for temperature. River level, turbine discharge and spillway discharge, although they showed no clear seasonal dynamics, were time-dependent, because the autocorrelation coefficients for different k values were significant. In the samples of larger-sized fish, 23 species were recorded during the two years of study. Most of the individuals were in a non reproductive state, and about 90% of the individuals belonged to only six species. The temporal variability in total abundance, considering all species, indicated a pattern of seasonal variation; high abundances occurred from October through February (75%) and in Pool A (61% of the 1343 individuals sampled). Low abundances were recorded during winter, with the correlogram of total density confirming this tendency. In the samples of smaller-sized species, six species were recorded, with all six present in both pools, but more frequent in the first pool (64%). Bryconamericus stramineus comprised 99% of the total numbers of smaller fish in the samples. The total abundance of small species showed different temporal patterns of seasonal variation in the two years of study.

Pela análise de seis sistemas enzimáticos (ACP, ALP, CAT, GOT, PPO e PO), com 18 locos polimórficos, foram calculadas as freqüências alélicas de 24 alelos referentes a 141 indivíduos adultos de uma população natural de Cryptocarya moschata (noz-moscada-do-Brasil) do Parque Estadual Carlos Botelho (24º03'21" S, 47º59'36" W), São Miguel Arcanjo, SP, amostrados em uma área de cerca de 647 ha. A estrutura genética espacial foi investigada através do método de autocorrelação espacial, utilizando-se coeficientes I de Moran estimados para 10 classes de distância. Adicionalmente, para as mesmas classes de distância, estimaram-se os coeficientes r através de uma análise multivariada. Ambas as abordagens mostraram-se similares qualitativamente, sendo que 15 correlogramas de coeficientes I foram significativos ao nível de 95% de probabilidade. O correlograma total gerado pelos coeficientes r indicou estruturação espacial significativa para a classe de distância de 0 a 150 m. Pela subdivisão desta classe em intervalos de 10 m, detectou-se autocorrelação espacial positiva na maioria das classes, indicando que os agrupamentos de árvores de C. moschata, que se encontram separadas a distâncias menores que 50 m, são constituídos por indivíduos semelhantes geneticamente e provavelmente aparentados. Contudo, a maior similaridade genética ocorreu entre indivíduos distanciados em torno de 105 m, podendo estar associada à dispersão de sementes promovida por Brachyteles arachnoides (Primates - Cebidae). Pela análise dos resultados, conclui-se que para uma amostragem adequada, visando a detecção de diversidade genética, a coleta de indivíduos distanciados acima de 750 m seria recomendável.

Through the analysis of six enzyme systems (ACP, ALP, CAT, GOT, PPO and PO), with 18 polymorphic loci, allele frequencies of 24 alleles were calculated for 141 adult individuals of a natural population of Cryptocarya moschata (Brazilian nutmeg), from Carlos Botelho State Park (24º03'21" S, 47º59'36" W), São Miguel Arcanjo, SP, Brazil, which were sampled in an area ca. 647 ha. The spatial genetic structure was investigated by the spatial autocorrelation method, using Moran's I coefficients estimated for 10 distance classes. Additionally, for the same distance classes, coefficients r were calculated through a multivariate analysis. Both approaches were qualitatively similar, poiting out that 15 correlograms from Moran's I coefficients were significant at 95% probability level. The total correlogram from r coefficients indicated that there was a significant spatial structure for the distance class of 0 to 150 m. By subdividing this class into 10 m intervals, positive spatial autocorrelation was detected in the majority of classes, suggesting that clusters of C. moschata trees, which were shorter than 50 m apart, were constituted of individuals with greater genetic similarity and were probably related. However, the greatest genetic similarity occurred among individuals being 105 m apart, which could be related to the kind of seed dispersal promoted by Brachyteles arachnoides (Primates - Cebidae). Results showed that for an adequate sampling, aiming to detect genetic diversity, the collection of individuals separated by a distance of 750 m, or more, from each other, would be advisable.