883 resultados para Nonlinear correlation coefficients
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A device and a specific procedure for simultaneous concentration of trace ele¬ments from sea water by co-precipitating them in precipitate of magnesium hydroxide obtained by electrolytic alkalization of samples in a two-chamber electrolyzer are described. Analyses of sea water samples for zinc, iron, copper, nickel and lead demonstrate that the method produces a thousand-fold concentration and gives results that agree well with those obtained by extractive concentration using diethyldithiocarbamate and 8-hydroxyquinoline in chloroform. Extracts were analyzed by flame atomic absorption. Correlation coefficients of results obtained with use of these two methods of concentration were 0.76-0.87 for zinc, iron, and copper at confidence levels of 0.05-0.07. Average zinc and iron concentrations determined by the method differed by less than 10%.
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As the length of marine cores increases and sampling intervals decrease, the need for rapid and inexpensive means of determining sediment composition has become apparent. In this study we examine one potentially useful technique for assessing compositional changes in marine cores, diffuse reflectance spectrophotometry. We examined near-ultraviolet, visible, and near-infrared reflectance spectra from five data sets. Each data set consists of calibration samples and test samples. The calibration samples' spectra were related to a sediment component using multiple linear regression. The resulting regression or calibration equations were then evaluated using the test samples. Calibration equations were written relating spectra to several sediment components incduding carbonate (Atlantic and east Pacific Rise ODP Site 847), organic carbon content (Atlantic and east Pacific Rise), and opal content (east Pacific Rise). The correlation coefficients for the regression equations ranged from a high of 0.99 for carbonate and opal at ODP Site 847 to a low of 0.97 for Atlantic carbonate indicating that spectral variations are highly correlated to sediment composition. All of the equations include a substantial number of variables from shorter visible and longer near ultraviolet wavelengths suggesting that these wavelengths are especially important for devices designed specifically to scan marine cores. Although equations for estimating organic and carbonate content appear independent of other sediment components, the opal equation is strongly dependent on carbonate content indicating that opal concentration is correlated to carbonate content. Tests of the calibration equations indicated that all our equations reasonably estimate the pattern of changes, either down core or in surface sediments. Where our spectral estimates have difficulty is with absolute values, frequently over or underestimating observed values by a substantial amount. Within these limitations diffuse reflectance spectrophotometry can be a useful tool for characterizing marine cores and as our understanding of the relationship between spectra and mineralogy improves so will estimates of absolute values.
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Sr contents in phosphorites on shelves of the Southwest Africa, and of Chile and Peru increase with degree of their lithification, from 0.05 to 0.28% and from 0.13 to 0.16% respectively. Phosphorites from Pacific submarine seamounts have the average Sr content 0.11%, and bone phosphate from Pacific floor 0.13%. Shelf phosphorites are characterized by high correlation coefficients between Sr and P2O5 (R = +0.82) and constant Sr/P2O5 ratio (0.0084). In phosphorites from submarine sea-mounts and in bones from the ocean floor Sr/P2O5 ratio is only a little higher than a half of that in shelf phosphorites. This indicates specific and different genesis of phosphorites from submarine mountains. Ba content in recent phosphorites from the shelf of the Southwest Africa changes with increasing degree of lithification. At first their Ba contents rise from 0.031 to 0.188%, then they diminish to 0.016%, and thereafter again increase to 0.070%. This is due to successive predominance of one of the following processes going in different directions: co-precipitation with phosphate gels or formation of true separate Ba phase, loss of phosphate in crystallization and "self-purification" of concentrations, and surface adsorption. In Peru-Chile shelf phosphorites the average Ba content is 0.017%, in phosphorites from Pacific seamounts 0.192%, and in fossilized bones 0.010%.
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We examine whether or not a relationship exists between the late Miocene carbon isotope shift (~7.6-6.6 Ma) and marine productivity at four sites from the Indian and Pacific Oceans (Ocean Drilling Program Sites 721, 1146, 1172, and 846). We use a multiproxy approach based on benthic foraminiferal accumulation rates, elemental ratios, and dissolution indices, and we compare these data to benthic foraminiferal d13C values measured on the same samples. Although some of these sites have been targeted previously in studies of either the late Miocene/early Pliocene "biogenic bloom" (Sites 721 and 846) or the late Miocene carbon isotope shift (Site 1172), our records are the first to establish paired proxy records of carbon isotopes and paleoproductivity allowing a direct assessment of a potential link. Our results indicate that at all sites, productivity increased sometime during the d13C shift; at three sites (721, 1146, and 846), productivity increased at the beginning of the shift. The correlation coefficients derived from linear regression between micropaleontologically derived productivity and foraminiferal d13C values are relatively high during the time interval containing the late Miocene d13C shift (and statistically significant at three of the sites). Carbon flux and isotope mass balance considerations illustrate that transfer of organic matter between the terrestrial and marine reservoirs together with enhanced oceanic upwelling best approximates observed changes in carbon isotope records and paleoproductivity. We note that long-term trend in the Site 846 paleoproductivity record can be correlated to the long-term trend in the Site 848 eolian flux reconstructions of Hovan (1995, doi:10.2973/odp.proc.sr.138.132.1995) hinting at a link between strengthened wind regime and productivity during the late Miocene.
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Integrated Ocean Drilling Program (IODP) Site U1308 (central North Atlantic) records paleomagnetic directional and relative paleointensity (RPI) variations for the last 1.5 Myr, in 110 m of the sediment sequence at a mean sedimentation rate of 7.3 cm/kyr. A detailed benthic oxygen isotope record was combined with RPI to produce an integrated, high-resolution magneto-isotopic stratigraphy for Site U1308. Apart from the well-known polarity reversals in this interval, the Punaruu excursion is recorded at 1092 ka and the Cobb Mountain Subchron in the 1182-1208 ka interval. The paleointensity proxies are determined as slopes of NRM versus ARM and NRM versus ARMAQ (ARM acquisition) with linear correlation coefficients to monitor the quality of the linear fit. The RPI record for Site U1308 is compared with the three other paleointensity records (one from the Western Equatorial Pacific and two from the North Atlantic) that cover the same time interval and have accompanying oxygen isotope records. The Match protocol of Lisiecki and Lisiecki (2002) is used to optimize the correlation of paleointensity records. Beginning with the original (published) age models for each record, the Match routine is used to optimize the RPI correlations to Site U1308, with checks to ensure compatibility with oxygen isotope records. Squared wavelet coherence (WTC) indicates significant improvement in RPI (and oxygen isotope) correlations after matching each RPI record to Site U1308, particularly for periods > 10 kyr. The level of coherence for the Atlantic RPI records and the lower resolution Pacific record implies synchronous global variability (at scales > 10 kyr) that can be attributed to the axial dipole geomagnetic field.
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The MBT-CBT proxy for the reconstruction of paleotemperatures and past soil pH is based on the distribution of branched glycerol dialkyl glycerol tetraether (brGDGT) membrane lipids. The Methylation of Branched Tetraether (MBT) and the Cyclisation of Branched Tetraether (CBT) indices were developed to quantify these distributions, and significant empirical relations between these indices and annual mean air temperature (MAT) and/or soil pH were found in a large data set of soils. In this study, we extended this soil dataset to 278 globally distributed surface soils. Of these soils, 26% contains all nine brGDGTs, while in 63% of the soils the seven most common brGDGTs were detected, and the latter were selected for calibration purposes. This resulted in new transfer functions for the reconstruction of pH based on the CBT index: pH = 7.90-1.97 × CBT (r**2 = 0.70; RMSE = 0.8; n = 176), as well as for MAT based on the CBT index and methylation index based on the seven most abundant GDGTs (defined as MBT'): MAT = 0.81-5.67 × CBT + 31.0 × MBT' (r**2 = 0.59; RMSE = 5.0 °C; n = 176). The new transfer function for MAT has a substantially lower correlation coefficient than the original equation (r**2 = 0.77). To investigate possible improvement of the correlation, we used our extended global surface soil dataset to statistically derive the indices that best describe the relations of brGDGT composition with MAT and soil pH. These new indices, however, resulted in only a relatively minor increase in correlation coefficients, while they cannot be explained straightforwardly by physiological mechanisms. The large scatter in the calibration cannot be fully explained by local factors or by seasonality, but MAT for soils from arid regions are generally substantially (up to 20 °C) underestimated, suggesting that absolute brGDGT-based temperature records for these areas should be interpreted with caution. The applicability of the new MBT'-CBT calibration function was tested using previously published MBT-CBT-derived paleotemperature records covering the last deglaciation in Central Africa and East Asia, the Eocene-Oligocene boundary and the Paleocene-Eocene thermal maximum. The results show that trends remain similar in all records, but that absolute temperature estimates and the amplitude of temperature changes are lower for most records, and generally in better agreement with independent proxy data.
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To investigate the geochemistry of trace elements in coals from the Dingji Mine of the Huainan Coalfield, Anhui province, China, 416 borehole samples of coal, one parting, two floor and two roof mudstones were collected from 9 minable coal seams in 24 boreholes drilled during exploration. The abundances of 47 elements in each sample were determined by various instruments. The boron concentration in the coals suggests that marine influence decreased from coal seam 1 to 13-1. The geometric means of the elements Sn, Bi, Sb, and B are higher than the average for the corresponding elements in the coals from China, the U.S., and world. The enrichment of certain elements in the Shanxi or Upper Shihezi Formations is related to their depositional environment. The roof, floor and parting samples have higher contents of some elements than coal seams. The mineral matters in the coals from the Dingji Mine were found to consist mainly of granular quartz, clay minerals, and carbonate minerals. The elements are classified into two groups based on their stratigraphic distribution from coal seam 1 to 13-1, and the characteristics of each group are discussed. Based on the correlation coefficients of elemental concentrations with ash yield, four groups of elements with different affinities were identified.
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La Organización Mundial de la Salud (OMS) prevé que para el año 2020, el Daño Cerebral Adquirido (DCA) estará entre las 10 causas más comunes de discapacidad. Estas lesiones, dadas sus consecuencias físicas, sensoriales, cognitivas, emocionales y socioeconómicas, cambian dramáticamente la vida de los pacientes y sus familias. Las nuevas técnicas de intervención precoz y el desarrollo de la medicina intensiva en la atención al DCA han mejorado notablemente la probabilidad de supervivencia. Sin embargo, hoy por hoy, las lesiones cerebrales no tienen ningún tratamiento quirúrgico que tenga por objetivo restablecer la funcionalidad perdida, sino que las terapias rehabilitadoras se dirigen hacia la compensación de los déficits producidos. Uno de los objetivos principales de la neurorrehabilitación es, por tanto, dotar al paciente de la capacidad necesaria para ejecutar las Actividades de Vida Diaria (AVDs) necesarias para desarrollar una vida independiente, siendo fundamentales aquellas en las que la Extremidad Superior (ES) está directamente implicada, dada su gran importancia a la hora de la manipulación de objetos. Con la incorporación de nuevas soluciones tecnológicas al proceso de neurorrehabilitación se pretende alcanzar un nuevo paradigma centrado en ofrecer una práctica personalizada, monitorizada y ubicua con una valoración continua de la eficacia y de la eficiencia de los procedimientos y con capacidad de generar conocimientos que impulsen la ruptura del paradigma de actual. Los nuevos objetivos consistirán en minimizar el impacto de las enfermedades que afectan a la capacidad funcional de las personas, disminuir el tiempo de incapacidad y permitir una gestión más eficiente de los recursos. Estos objetivos clínicos, de gran impacto socio-económico, sólo pueden alcanzarse desde una apuesta decidida en nuevas tecnologías, metodologías y algoritmos capaces de ocasionar la ruptura tecnológica necesaria que permita superar las barreras que hasta el momento han impedido la penetración tecnológica en el campo de la rehabilitación de manera universal. De esta forma, los trabajos y resultados alcanzados en la Tesis son los siguientes: 1. Modelado de AVDs: como paso previo a la incorporación de ayudas tecnológicas al proceso rehabilitador, se hace necesaria una primera fase de modelado y formalización del conocimiento asociado a la ejecución de las actividades que se realizan como parte de la terapia. En particular, las tareas más complejas y a su vez con mayor repercusión terapéutica son las AVDs, cuya formalización permitirá disponer de modelos de movimiento sanos que actuarán de referencia para futuros desarrollos tecnológicos dirigidos a personas con DCA. Siguiendo una metodología basada en diagramas de estados UML se han modelado las AVDs 'servir agua de una jarra' y 'coger un botella' 2. Monitorización ubícua del movimiento de la ES: se ha diseñado, desarrollado y validado un sistema de adquisición de movimiento basado en tecnología inercial que mejora las limitaciones de los dispositivos comerciales actuales (coste muy elevado e incapacidad para trabajar en entornos no controlados); los altos coeficientes de correlación y los bajos niveles de error obtenidos en los corregistros llevados a cabo con el sistema comercial BTS SMART-D demuestran la alta precisión del sistema. También se ha realizado un trabajo de investigación exploratorio de un sistema de captura de movimiento de coste muy reducido basado en visión estereoscópica, habiéndose detectado los puntos clave donde se hace necesario incidir desde un punto de vista tecnológico para su incorporación en un entorno real 3. Resolución del Problema Cinemático Inverso (PCI): se ha diseñado, desarrollado y validado una solución al PCI cuando el manipulador se corresponde con una ES humana estudiándose 2 posibles alternativas, una basada en la utilización de un Perceptrón Multicapa (PMC) y otra basada en sistemas Artificial Neuro-Fuzzy Inference Systems (ANFIS). La validación, llevada a cabo utilizando información relativa a los modelos disponibles de AVDs, indica que una solución basada en un PMC con 3 neuronas en la capa de entrada, una capa oculta también de 3 neuronas y una capa de salida con tantas neuronas como Grados de Libertad (GdLs) tenga el modelo de la ES, proporciona resultados, tanto de precisión como de tiempo de cálculo, que la hacen idónea para trabajar en sistemas con requisitos de tiempo real 4. Control inteligente assisted-as-needed: se ha diseñado, desarrollado y validado un algoritmo de control assisted-as-needed para una ortesis robótica con capacidades de actuación anticipatoria de la que existe un prototipo implementado en la actualidad. Los resultados obtenidos demuestran cómo el sistema es capaz de adaptarse al perfil disfuncional del paciente activando la ayuda en instantes anteriores a la ocurrencia de movimientos incorrectos. Esta estrategia implica un aumento en la participación del paciente y, por tanto, en su actividad muscular, fomentándose los procesos la plasticidad cerebral responsables del reaprendizaje o readaptación motora 5. Simuladores robóticos para planificación: se propone la utilización de un simulador robótico assisted-as-needed como herramienta de planificación de sesiones de rehabilitación personalizadas y con un objetivo clínico marcado en las que interviene una ortesis robotizada. Los resultados obtenidos evidencian como, tras la ejecución de ciertos algoritmos sencillos, es posible seleccionar automáticamente una configuración para el algoritmo de control assisted-as-needed que consigue que la ortesis se adapte a los criterios establecidos desde un punto de vista clínico en función del paciente estudiado. Estos resultados invitan a profundizar en el desarrollo de algoritmos más avanzados de selección de parámetros a partir de baterías de simulaciones Estos trabajos han servido para corroborar las hipótesis de investigación planteadas al inicio de la misma, permitiendo, asimismo, la apertura de nuevas líneas de investigación. Summary The World Health Organization (WHO) predicts that by the year 2020, Acquired Brain Injury (ABI) will be among the ten most common ailments. These injuries dramatically change the life of the patients and their families due to their physical, sensory, cognitive, emotional and socio-economic consequences. New techniques of early intervention and the development of intensive ABI care have noticeably improved the survival rate. However, in spite of these advances, brain injuries still have no surgical or pharmacological treatment to re-establish the lost functions. Neurorehabilitation therapies address this problem by restoring, minimizing or compensating the functional alterations in a person disabled because of a nervous system injury. One of the main objectives of Neurorehabilitation is to provide patients with the capacity to perform specific Activities of the Daily Life (ADL) required for an independent life, especially those in which the Upper Limb (UL) is directly involved due to its great importance in manipulating objects within the patients' environment. The incorporation of new technological aids to the neurorehabilitation process tries to reach a new paradigm focused on offering a personalized, monitored and ubiquitous practise with continuous assessment of both the efficacy and the efficiency of the procedures and with the capacity of generating new knowledge. New targets will be to minimize the impact of the sicknesses affecting the functional capabilitiies of the subjects, to decrease the time of the physical handicap and to allow a more efficient resources handling. These targets, of a great socio-economic impact, can only be achieved by means of new technologies and algorithms able to provoke the technological break needed to beat the barriers that are stopping the universal penetration of the technology in the field of rehabilitation. In this way, this PhD Thesis has achieved the following results: 1. ADL Modeling: as a previous step to the incorporation of technological aids to the neurorehabilitation process, it is necessary a first modelling and formalization phase of the knowledge associated to the execution of the activities that are performed as a part of the therapy. In particular, the most complex and therapeutically relevant tasks are the ADLs, whose formalization will produce healthy motion models to be used as a reference for future technological developments. Following a methodology based on UML state-chart diagrams, the ADLs 'serving water from a jar' and 'picking up a bottle' have been modelled 2. Ubiquitous monitoring of the UL movement: it has been designed, developed and validated a motion acquisition system based on inertial technology that improves the limitations of the current devices (high monetary cost and inability of working within uncontrolled environments); the high correlation coefficients and the low error levels obtained throughout several co-registration sessions with the commercial sys- tem BTS SMART-D show the high precision of the system. Besides an exploration of a very low cost stereoscopic vision-based motion capture system has been carried out and the key points where it is necessary to insist from a technological point of view have been detected 3. Inverse Kinematics (IK) problem solving: a solution to the IK problem has been proposed for a manipulator that corresponds to a human UL. This solution has been faced by means of two different alternatives, one based on a Mulilayer Perceptron (MLP) and another based on Artificial Neuro-Fuzzy Inference Systems (ANFIS). The validation of these solutions, carried out using the information regarding the previously generated motion models, indicate that a MLP-based solution, with an architecture consisting in 3 neurons in the input layer, one hidden layer of 3 neurons and an output layer with as many neurons as the number of Degrees of Freedom (DoFs) that the UL model has, is the one that provides the best results both in terms of precission and in terms of processing time, making in idoneous to be integrated within a system with real time restrictions 4. Assisted-as-needed intelligent control: an assisted-as-needed control algorithm with anticipatory actuation capabilities has been designed, developed and validated for a robotic orthosis of which there is an already implemented prototype. Obtained results demonstrate that the control system is able to adapt to the dysfunctional profile of the patient by triggering the assistance right before an incorrect movement is going to take place. This strategy implies an increase in the participation of the patients and in his or her muscle activity, encouraging the neural plasticity processes in charge of the motor learning 5. Planification with a robotic simulator: in this work a robotic simulator is proposed as a planification tool for personalized rehabilitation sessions under a certain clinical criterium. Obtained results indicate that, after the execution of simple parameter selection algorithms, it is possible to automatically choose a specific configuration that makes the assisted-as-needed control algorithm to adapt both to the clinical criteria and to the patient. These results invite researchers to work in the development of more complex parameter selection algorithms departing from simulation batteries Obtained results have been useful to corroborate the hypotheses set out at the beginning of this PhD Thesis. Besides, they have allowed the creation of new research lines in all the studied application fields.
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The aim of the study was to evaluate the inter-operator reliability of OPTA Client System which is used to collect live football match statistics by OPTA Sportsdata Company. Two groups of experienced operators were required to analyze a Spanish league match independently. Results showed that team events coded by independent operators reached a very good agreement (kappa values were 0.92 and 0.94) and average difference of event time was 0.06±0.04 s. The reliability of goalkeeper actions was also at high level, kappa values were 0.92 and 0.86. The high intra-class correlation coefficients (ranged from 0.88 to 1.00) and low standardized typical errors (varied from 0.00 to 0.37) of different match actions and indicators of individual outfield players showed a high level of inter-operator reliability as well. These results suggest that the OPTA Client System is reliable to be used to collect live football match statistics by well trained operators.
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The present paper describes the advancement and evaluation of air quality-related impacts with the Atmospheric Evaluation and Research Integrated system for Spain (AERIS). In its current version, AERIS is able to provide estimates on the impacts of air quality over human health (PM2.5 and O3), crops and vegetation (O3). The modules that allow quantifying the before mentioned impacts were modeled by applying different approaches (mostly for the European context) present in scientific literature to the conditions of the Iberian Peninsula. This application was supported by reliable data sources, as well as by the good predictive capacity of AERIS for ambient concentrations. For validation purposes, the estimates of AERIS for impacts on human health (change in the statistical life expectancy-PM2.5) and vegetation (loss of wheat crops-O3) were compared against results from the SERCA project and GAINS estimates for two emission scenarios. In general, good results evidenced by reasonable correlation coefficients were obtained, therefore confirming the adequateness of the followed modeling approaches and the quality of AERIS predictions.
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El análisis del rendimiento en deportes juega un papel esencial en el fútbol profesional. Aunque el estudio del análisis del juego en fútbol se ha utilizado desde diferentes ámbitos y situaciones, todavía existen diferentes aspectos y componentes del juego que siguen sin estar estudiados. En este sentido existen diferentes aspectos que deben de superar los estudios previos centrados en el componente descriptivo tales como el uso de variables/ indicadores de rendimiento que no se han definido ni estudiado, la validez de los métodos observaciones que no han sido testados con los softwares específicos en fútbol, la aplicación y utilidad de los resultados, así como las limitaciones del estudio de las variables situacionales/contextuales. Con el objetivo de cubrir las citadas limitaciones se han diseñado 6 estudios independientes e inter-relacionados que tratan de estudiar los aspectos anteriormente referidos. El primer estudio evalua la fiabilidad inter-observadores de las estadísticas de juego de la empresa privada OPTA Sportsdata, estos datos son la muestra de estudio de la presente tesis doctoral. Dos grupos de observadores experimentados se requieren para analizar un partido de la liga española de manera independiente. Los resultados muestran que los eventos de equipos y porteros codificados por los inter-operadores alcanzan un acuerdo muy bueno (valores kappa entre 0.86 y 0.94). La validez inter-observadores de las acciones de juego y los datos de jugadores individuales se evaluó con elevados niveles de acuerdo (valores del coeficiente de correlación intraclase entre 0.88 hasta 1.00, el error típico estandarizado variaba entre 0.00 hasta 0.37). Los resultados sugieren que las estadísticas de juego registradas por los operadores de la empresa OPTA Sportsdata están bien entrenados y son fiables. El segundo, tercer y cuarto estudio se centran en resaltar la aplicabilidad del análisis de rendimiento en el fútbol así como para explicar en profundidad las influencias de las variables situacionales. Utilizando la técnica de los perfiles de rendimiento de jugadores y equipos de fútbol se puede evaluar y comparar de manera gráfica, fácil y visual. Así mismo, mediante esta técnica se puede controlar el efecto de las variables situacionales (localización del partido, nivel del equipo y del oponente, y el resultado final del partido). Los perfiles de rendimiento de porteros (n = 46 porteros, 744 observaciones) y jugadores de campo (n = 409 jugadores, 5288 observaciones) de la primera division professional de fútbol Española (La Liga, temporada 2012-13), los equipos (n = 496 partidos, 992 observaciones) de la UEFA Champions League (temporadas 2009-10 a 2012-13) fueron analizados registrando la media, desviación típica, mediana, cuartiles superior e inferior y el recuento de valores de cada indicador de rendimiento y evento, los cuales se presentaron en su forma tipificada y normalizada. Los valores medios de los porteros de los equipos de diferentes niveles de La Liga y de los equipos de diferente nivel de la UEFA Champions League cuando jugaban en diferentes contextos de juego y situaciones (variables situacionales) fueron comparados utilizando el ANOVA de un factor y la prueba t para muestras independientes (localización del partido, diferencias entre casa y fuera), y fueron establecidos en los perfiles de red después de unificar todos los registros en la misma escala derivada con valores estandarizados. Mientras que las diferencias de rendimiento entre los jugadores de los mejores equipos (Top3) y los peores (Bottom3) fueron comparados mediante el uso de diferencias en la magnitud del tamaño del efecto. El quinto y el sexto estudio analizaban el rendimiento del fútbol desde un punto de vista de predicción del rendimiento. El modelo linear general y el modelo lineal general mixto fue empleado para analizar la magnitud de las relaciones de los indicadores y estadísticas de juego con el resultado final del partido en función del tipo de partido (partidos ajustados o todos los partidos) en la fase de grupos de la Copa del Mundo 2014 de Brasil (n = 48 partidos, 38 partidos ajustados) y La Liga 2012-13 (n = 320 partidos ajustados). Las relaciones fueron evaluadas mediante las inferencias en la magnitud de las diferencias y se expresaron como partidos extra ganados o perdidos por cada 10 partidos mediante la variable calculada en 2 desviaciones típicas. Los resultados mostraron que, para los 48 partidos de la fase de grupos de la Copa del Mundo 2014, nueve variables tuvieron un efecto positive en la probabilidad de ganar (tiros, tiros a puerta, tiros de contraataque, tiros dentro del área, posesión de balón, pases en corto, media de secuencia de pases, duelos aéreos y entradas), cuatro tuvieron efectos negativos (tiros bloqueados, centros, regates y tarjetas amarillas), y otras 12 variables tenían efectos triviales o poco claros. Mientras que los 38 partidos ajustados, el efecto de duelos aéreos y tarjetas amarillas fueron triviales y claramente negativos respectivamente. En la La Liga, existió un efecto moderado positive para cada equipo para los tiros a puerta (3.4 victorias extras por cada 10 partidos; 99% IC ±1.0), y un efecto positivo reducido para tiros totales (1.7 victorias extrsa; ±1.0). Los efectos de la mayoría de los eventos se han relacionado con la posesión del balón, la cual obtuvo efectos negativos entre equipos (1.2 derrotas extras; ±1.0) pero un efecto positivo pequeño entra equipos (1.7 victorias extras; ±1.4). La localización del partido mostró un efecto positive reducido dentro de los equipos (1.9 victorias extras; ±0.9). Los resultados obtenidos en los perfiles y el modelado del rendimiento permiten ofrecer una información detallada y avanzada para el entrenamiento, la preparación previa a los partidos, el control de la competición y el análisis post-partido, así como la evaluación e identificación del talento de los jugadores. ABSTRACT Match performance analysis plays an important role in the modern professional football. Although the research in football match analysis is well-developed, there are still some issues and problems remaining in this field, which mainly include the lack of operational definitions of variables, reliability issues, applicability of the findings, the lack of contextual/situational variables, and focusing too much on descriptive and comparative analysis. In order to address these issues, six independent but related studies were conducted in the current thesis. The first study evaluated the inter-operator reliability of football match statistics from OPTA Sportsdata Company which is the data resourse of the thesis. Two groups of experienced operators were required to analyse a Spanish league match independently in the experiment. Results showed that team events and goalkeeper actions coded by independent operators reached a very good agreement (kappa values between 0.86 and 0.94). The inter-operator reliability of match actions and events of individual outfield players was also tested to be at a high level (intra-class correlation coefficients ranged from 0.88 to 1.00, standardised typical error varied from 0.00 to 0.37). These results suggest that the football match statistics collected by well-trained operators from OPTA Sportsdata Company are reliable. The second, third and fourth study aims to enhance the applicability of football match performance analysis and to explore deeply the influences of situational variables. By using a profiling technique, technical and tactical performances of football players and teams can be interpreted, evaluated and compared more easily and straightforwardly, meanwhile, influences and effects from situational variables (match location, strength of team and opposition, and match outcome) on the performances can be properly incorporated. Performance profiles of goalkeepers (n = 46 goalkeepers, 744 full match observations) and outfield players (n = 409 players, 5288 full match observations) from the Spanish First Division Professional Football League (La Liga, season 2012-13), teams (n = 496 matches, 992 observations) from UEFA Champions League (seasons 2009-10 to 2012-13) were set up by presenting the mean, standard deviation, median, lower and upper quartiles of the count values of each performance-related match action and event to represent their typical performances and spreads. Means of goalkeeper from different levels of team in La Liga and teams of different strength in UEFA Champions League when playing under different situational conditions were compared by using one-way ANOVA and independent sample t test (for match location, home and away differences), and were plotted into the same radar charts after unifying all the event counts by standardised score. While differences between the performances of outfield players from Top3 and from Bottom3 teams were compared by magnitude-based inferences. The fifth and sixth study aims to move from the descriptive and comparative football match analysis to a more predictive one. Generalised linear modelling and generalised mixed linear modelling were undertaken to quantify relationships of the performance-related match events, actions and variables with the match outcome in different types of games (close games and all games) in the group stage of 2014 Brazil FIFA World Cup (n = 48 games, 38 close games) and La Liga 2012-13 (n = 320 close games). Relationships were evaluated with magnitude-based inferences and were expressed as extra matches won or lost per 10 matches for an increase of two standard deviations of a variable. Results showed that, for all the 48 games in the group stage of 2014 FIFA World Cup, nine variables had clearly positive effects on the probability of winning (shot, shot on target, shot from counter attack, shot from inside area, ball possession, short pass, average pass streak, aerial advantage, and tackle), four had clearly negative effects (shot blocked, cross, dribble and red card), other 12 variabless had either trivial or unclear effects. While for the 38 close games, the effects of aerial advantage and yellow card turned to trivial and clearly negative, respectively. In the La Liga, there was a moderate positive within-team effect from shots on target (3.4 extra wins per 10 matches; 99% confidence limits ±1.0), and a small positive within-team effect from total shots (1.7 extra wins; ±1.0). Effects of most other match events were related to ball possession, which had a small negative within-team effect (1.2 extra losses; ±1.0) but a small positive between-team effect (1.7 extra wins; ±1.4). Game location showed a small positive within-team effect (1.9 extra wins; ±0.9). Results from the established performance profiles and modelling can provide detailed and straightforward information for training, pre-match preparations, in-match tactical approaches and post-match evaluations, as well as for player identification and development. 摘要 比赛表现分析在现代足球中起着举足轻重的作用。尽管如今对足球比赛表现分析的研究已经相对完善,但仍有很多不足之处。这些不足主要体现在:研究中缺乏对研究变量的清晰定义、数据信效度缺失、研究结果的实用性受限、比赛情境因素缺失以及过于集中在描述性和对比性分析等。针对这些问题,本论文通过六个独立而又相互联系的研究,进一步对足球比赛表现分析进行完善。 第一个研究对本论文的数据源--OPTA Sportsdata公司的足球比赛数据的信效度进行了实验检验。实验中,两组数据收集人员被要求对同一场西班牙足球甲级联赛的比赛进行分析。研究结果显示,两组收集人员记录下的球队比赛事件和守门员比赛行为具有高度的一致性(卡帕系数介于0.86和0.94)。收集人员输出的外场球员的比赛行为和比赛事件也具有很高的组间一致性(ICC相关系数介于0.88和1.00,标准化典型误差介于0.00和0.37)。实验结果证明了OPTA Sportsdata公司收集的足球比赛数据具有足够高的信效度。 第二、三、四个研究旨在提升足球比赛表现分析研究结果的实用性以及深度探讨比赛情境因素对足球比赛表现的影响。通过对足球运动员和运动队的比赛技战术表现进行档案创建,可以对运动员和运动队的比赛表现进行简直接而直观的呈现、评价和对比,同时,情境变量(比赛场地、球队和对手实力、比赛结果)对比赛表现的影响也可以被整合到表现档案中。本部分对2012-13赛季西班牙足球甲级联赛的参赛守门员(n = 46球员人次,744比赛场次)和外场球员(n = 409球员人次, 5288比赛场次)以及2009-10至2012-13赛季欧洲足球冠军联赛的参赛球队(n = 496比赛场次)的比赛技战术表现进行了档案创建。在表现档案中,各项比赛技战术指标的均值、标准差、中位数和大小四分位数被用来展现守门员、外场球员和球队的普遍表现和表现浮动性。方差分析(ANOVA)被用来对西甲不同水平球队的守门员、欧冠中不同水平球队在不同比赛情境下的普遍表现(各项指标的均值)进行对比,独立样本t检验被用来对比主客场比赛普遍表现的差异。数据量级推断(magnitude-based inferences)的方法则被用来对西甲前三名和最后三名球队外场球员的普遍表现进行对比分析。所有来自不同水平球队的运动员和不同水平运动队的各项比赛指标皆被转换成了标准分数,从而能把他们在各种不同比赛情境下的普遍表现(各项比赛指标的均值)投到相同的雷达图中进行直观的对比。 第五和第六个研究目的在于进行预测性足球比赛表现分析,从而跨越之前固有的描述性和对比性分析。广义线性模型和广义混合线性模型被用来对2014年巴西世界杯小组赛(n = 48 比赛场次,38小分差场次)和2012-13赛季西甲联赛(n = 320小分差场次)的比赛中各表现相关比赛事件、行为和变量与比赛结果(胜、平、负)的关系进行建模。模型中的关系通过数据量级推断(magnitude-based inferences)的方法来界定,具体表现为某个变量增加两个标准差对比赛结果的影响(每10场比赛中额外取胜或失利的场数)。研究结果显示,在2014年巴西世界杯小组赛的所有48场比赛中,9个变量(射门、射正、反击中射门、禁区内射门、控球、短传、连续传球平均次数、高空球争抢成功率和抢断)与赢球概率有清晰的正相关关系,4个变量(射门被封堵、传中、过人和红牌)与赢球概率有清晰的负相关关系,其他12个被分析的变量与赢球概率的相关关系微小或不清晰。而在38场小分差比赛中,高空球争抢成功率由正相关变为微小关系,黄牌则由微小关系变为清晰的负相关。在西甲联赛中,每一支球队增加两个标准差的“射正球门”可以给每10场比赛带来3.4场额外胜利(99%置信区间±1.0场),而所有球队作为一个整体,每增加两个标准差的“射正球门”可以给每10场比赛带来1.7场额外胜利(99%置信区间±1.0场)。其他大多数比赛相关事件与比赛结果的相关关系与“控球”相关联。每一支球队增加两个标准差的“控球”将会给每10场比赛带来1.2场额外失利(99%置信区间±1.0场),而所有球队作为一个整体,每增加两个标准差的“控球”可以给每10场比赛带来1.7场额外胜利(99%置信区间±1.4场)。与客场比赛相对,主场能给球队带来1.9 /10场额外胜利(99%置信区间±0.9场)。 比赛表现档案和模型中得出的研究结果可以为俱乐部、足球队、教练组、表现分析师和运动员提供详细而直接的参考信息。这些信息可用于训练指导、赛前备战、赛中技战术调整和赛后技战术表现分析,也可运用于足球运动员选材、培养和发展。
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Sudamérica es una de las zonas con mayor cantidad de bosque seco tropical a nivel mundial. No obstante, estos bosques han sido poco conocidos y la mayoría de estudios han estado orientados hacia los bosques húmedos tropicales. Los bosques secos se han reducido drásticamente y siguen muy amenazados, corriendo el riesgo de desaparecer en los próximos años. Por ello, es fundamental, generar investigación aplicada para la conservación inmediata de los ecosistemas secos tropicales. En Ecuador, la situación no es diferente y las zonas secas catalogadas como biodiversas están en constante amenaza. Los pocos estudios realizados en Ecuador sobre zonas secas, han permitido mejorar nuestro conocimiento referente a la diversidad y abundancia de las especies, relaciones planta-planta y síndromes de dispersión. No existen estudios sobre caracteres morfológicos en frutos y semillas de las especies leñosas de bosque seco. Sin embargo, nuestra comprensión de la dinámica y estructura de las comunidades ecológicas de zonas secas poco estudiadas, puede mejorar rápidamente mediante el estudio y enfoque de rasgos morfofisiológicos funcionales. El objetivo general del presente estudio fue aportar al conocimiento de la ecología y biología de semillas de zonas secas tropicales mediante el análisis y evaluación de rasgos morfofisiológicos de frutos y semillas de una comunidad de especies leñosas. El estudio se realizó en una zona de bosque y matorral seco, ubicados al sur occidente del Ecuador, a una altitud comprendida entre los 250 a 1 200 m s.n.m. caracterizada por una marcada estacionalidad ambiental, con lluvias desde diciembre a abril y una estación seca de mayo a noviembre. Precipitación media anual de 500 mm con una temperatura media anual de 20° a 26 °C. La zona de estudio forma parte de la región Tumbesina compartida entre el sur del Ecuador y el norte del Perú con gran diversidad de especies vegetales endémicas. Para el estudio se colectaron frutos con semillas maduras previamente a su dispersión de entre ocho y diez individuos de 80 especies entre árboles y arbustos más representativos de los bosques secos ecuatorianos. De los frutos colectados se utilizó una muestra al azar de 50 frutos y semillas por especie para los diferentes análisis. Se midió y evaluó 18 rasgos morfológicos y fisiológicos cuantitativos y cualitativos de frutos, semillas y de la especie. Se realizaron diferentes análisis de asociación y correlación entre los rasgos evaluados, con cinco variables ambientales registradas de las 109 parcelas establecidas en el área de estudio, además analizamos el tipo de dormición y comparamos la respuesta germinativa a la deshidratación relacionada con dos comunidades secas, matorral y bosque seco. Los resultados mostraron que las especies presentan gran heterogeneidad en rasgos continuos de las semillas. La variabilidad fue más evidente en rasgos como tamaño, volumen, masa y número de semillas por fruto. Sin embargo, una alta proporción de las especies tiende a producir una semilla por fruto. Además, la mayoría de las especies de bosque seco se caracterizan por no poseer algún tipo de apéndices o areola en sus semillas, forma ovalada y sin endospermo. La reserva nutritiva de las semillas se encuentra especialmente en los cotiledones de los embriones. Se encontraron seis tipos diferentes de embriones y la mayoría de las especies presentó embriones gruesos e invertidos. La dispersión de semillas está dominada por zoocoria en un 38 %, con relación a anemocoria (22 %) y autocoria (19 %). Sin embargo, encontramos que el 70 % de las especies posee frutos secos. Los análisis de dormición en las semillas de bosque seco, mostraron que el 60 % de las especies de bosque seco presentaron semillas con algún tipo de latencia, menor a la encontrada en especies de bosque deciduo tropical y sabanas, sin embargo, la dormición de las especies de bosque seco fue mayor al porcentaje de especies con dormición de bosque semiperenne y selva lluviosa tropical. La dormición física constituyó el 35 % de las especies de bosque seco, seguido del 12 % con dormición fisiológica, mientras que solamente una especie tuvo dormición morfológica. Encontramos que la dormición de las semillas de las especies en estudio se relaciona significativamente con el tipo y función del embrión y con el endospermo. Existieron relaciones significativas entre los rasgos morfológicos de los frutos, semillas, embriones y atributos de los individuos de 46 especies, aunque en algunos casos con coeficientes de correlación bajos. Hubo pocas relaciones entre los rasgo morfológicos de las semillas con las variables ambientales registradas. Solamente el tipo de testa y la presencia de apéndices en las semillas mostraron relación con el pH y la temperatura media del suelo. No obstante usando el modelo fouth corner-RLQ, no se encontraron asociaciones claras ni significativas entre rasgos morfológicos de semillas y frutos con variables ambientales. Al medir el efecto de la deshidratación en las semillas de los dos hábitats secos tropicales: bosque y matorral seco, los resultados determinaron que tanto las semillas de las especies leñosas de ambientes más áridos (matorral seco) están en gran medida pre-adaptadas a la desecación que las especies de ambientes menos áridos (bosque seco). Los tratamientos de deshidratación ejercieron un efecto negativo en los porcentajes de germinación en todas las especies, excepto para C. platanifolia. Los resultados más sorprendentes se registraron para Senna alata que mostró germinación extremadamente baja o incluso sin germinación a contenidos de humedad de la semillas de 0,10 g H2O g de peso seco. Las curvas de germinación difirieron significativamente entre los tratamientos de deshidratación en cada especie. Aportar al conocimiento la fisiología de la deshidratación y los límites de tolerancia de las semillas de bosque y matorral seco ayudará a entender mejor el papel de este rasgo en la ecología de las semillas y dinámica de las comunidades áridas tropicales. El estudio demostró, que la adaptación ecológica de las semillas de las especies leñosas de bosque seco a factores ambientales extremos, puede verse reflejada en una red de interacciones y correlaciones complejas entre los propios rasgos morfológicos y fisiológicos continuos y cuantitativos, sobre todo en rasgos internos de las semillas, quienes ejercerían una mayor influencia en toda la red de interacciones. Si bien, los rasgos de las semillas no mostraron fuertes relaciones con las variables ambientales, posiblemente las asociaciones presentes entre rasgos morfológicos pudiesen predecir en cambio interacciones entre especies y comportamientos y procesos relacionados con la tolerancia a la deshidratación y dormición de las semillas. ABSTRACT South America is one of the areas with the largest number of tropical dry forest in the world. However, these forests have been poorly understood and most studies have been directed to tropical rainforests. Dry forests have been drastically reduced and are very threatened, risking desaparecerer in the next years. It is therefore essential, generate applied research for conservation of tropical dry ecosystems. In Ecuador the situation is no different and dry areas classified as biodiverse are under constant threat. The few studies made in Ecuador on drylands have improved our knowledge concerning the diversity and abundance of species, plant-plant relationships and dispersion syndromes. Morphological studies on fruits and seeds of woody dry forest species do not exist. However, our understanding of the dynamics and structure of ecological communities dryland little studied, may improve quickly through the study and functional approach morphophysiological traits. The overall objective of this study was to contribute to the knowledge of the ecology and biology of tropical dry seeds through analysis and evaluation of morphophysiological traits of fruits and seeds of a community of woody species. The study was conducted in an area of dry scrub forest, located at the southwest of Ecuador, at an altitude between 250 to 1200 m asl. Environmental characterized by a marked seasonality, with rainfall from December to April and a dry season from May to November. Annual rainfall of 500 mm with an average annual temperature of 20° to 26 °C. The study area is part of the shared Tumbesina region between southern Ecuador and northern Peru with a great diversity of endemic plant species. For the study, we collected fruit and seed madure of eight and ten individuos of 80 species of trees and shrub most representated of the Ecuador dry forest. We selected a sample of 50 fruits and seeds for different analysis. We measure and evaluate 18 morphological and physiological traits of fruits, seeds and species. We perform analysis and correlation between traits associated with five environmental variables taken from the 109 plots established in the study area also analyze and compare the germination response to dehydration related to two dry communities, scrub and dry forest. The results showed that the species have great heterogeneity in continuous seed traits. Variability was more evident in features such as size, volume, mass, and number of seeds per fruit. However, a high proportion of species tends to produce a seed per fruit. In addition, most of the species of dry forest is characterized by not having some sort of ppendices or areola in its seeds, oval form and without endosperm. The nutrient reserves of seeds are especially in the cotyledons of the embryos. Six different embryos were found and most of the species presented thick and inverted embryos. Seed dispersal zoochory is dominated by 38 %, relative to anemochory (22 %) and autochory (19 %). However, we found that 70 % of the species has dried fruits. The analysis of dormancy from tropical dry forest, showed that 60 % of species showed seed dormancy, down from species found in tropical deciduous forest and savanna, however dormancy dry forest species was higher than the percentage of forest species dormancy semi-evergreen and tropical rain forest. Physical dormancy corresponds to 35 % of species, followed by 12 % with physiological dormancy, while only one species had morphological dormancy. We found that dormancy of the seeds was significantly related to the type and function of the embryo and the endospemo. There were significant relationships between morphological traits of fruits, seeds, embryos and attributes of individuals of 46 species, although in some cases with low correlation coefficients. There was little relationship between the morphologic traits of the seeds with the registered environmental variables. Only the type of tesla and the presence of appendages on the seeds showed relation to pH and the mean soil temperature. However, using the fourth corner-RLQ model, neither clear nor significant between morphological traits of seeds and fruits associations with environmental variables were found. The effect of dehydration on seeds of two tropical dry forest habitats was evident in dry scrub. The results determined that both the seeds of woody species forest and dry scrub are pre-adapted to drier conditions. Dehydration treatments exerted a negative effect on germination percentage in all species, except for C. platanifolia. However, all species germinated in treatments of extreme dryness, but in low percentages. The most striking results were recorded for Senna alata showed no germination when its moisture content was 0.10 g H2O g dry weight. Germination curves differ significantly between the treatments of dehydration in each species. Contribute to the knowledge of physiology and dehydration tolerance limits seeds dry scrub forest and help you better understand the role of this trait in seed ecology and dynamics of tropical arid communities. The study showed that the ecological adaptation of seeds of woody species of dry forest to extreme environmental factors may be reflected in a complex web of interactions and correlations between morphological and physiological traits continuous and quantitative themselves, especially in internal seed traits, who exerted a major influence on the entire network of interactions. While the seed traits showed strong relationships with environmental variables possibly present associations between morphological traits could predict interactions between species and change behaviors related to desiccation tolerance and seed dormancy processes.
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The relationship between the chemical composition and the multispectral reflectance values of chromite in the VNIR (Visible and Near-Infra-Red) realm is tested and mathematically analysed. Statisticaltools as Pearson's correlation coefficients, linear stepwise regression analysis and least-square adjustments are applied to two populations of data obtained from 14 selected samples 01 chromite multielemental microprobe analysis and multispectral reflectance values (400-1 000 nm). Results show that both data sets correlate, and suggest that the VNIR reflectance spectra can be used as a tool to determine the chemical composition of chromites.
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Introdução: Grande parte das ações para promover a atividade física no lazer em populações tem apresentado tamanhos de efeito pequenos ou inexistentes, ou resultados inconsistentes. Abordar o problema a partir da perspectiva sistêmica pode ser uma das formas de superar esse descompasso. Objetivo: Desenvolver um modelo baseado em agentes para investigar a conformação e evolução de padrões populacionais de atividade física no lazer em adultos a partir da interação entre atributos psicológicos dos indivíduos e atributos dos ambientes físico construído e social em que vivem. Métodos: O processo de modelagem foi composto por três etapas: elaboração de um mapa conceitual, com base em revisão da literatura e consulta com especialistas; criação e verificação do algoritmo do modelo; e parametrização e análise de consistência e sensibilidade. Os resultados da revisão da literatura foram consolidados e relatados de acordo com os domínios da busca (aspectos psicológicos, ambiente social e ambiente físico construído). Os resultados quantitativos da consulta com os especialistas foram descritos por meio de frequências e o conteúdo das respostas questões abertas foi analisado e compilado pelo autor desta tese. O algoritmo do modelo foi criado no software NetLogo, versão 5.2.1., seguindo-se um protocolo de verificação para garantir que o algoritmo fosse implementado acuradamente. Nas análises de consistência e sensibilidade, utilizaram-se o Teste A de Vargha-Delaney, coeficiente de correlação de postos parcial, boxplots e gráficos de linha e de dispersão. Resultados: Definiram-se como elementos do mapa conceitual a intenção da pessoa, o comportamento de pessoas próximas e da comunidade, e a percepção da qualidade, do acesso e das atividades disponíveis nos locais em que atividade física no lazer pode ser praticada. O modelo representa uma comunidade hipotética contendo dois tipos de agentes: pessoas e locais em que atividade física no lazer pode ser praticada. As pessoas interagem entre si e com o ambiente construído, gerando tendências temporais populacionais de prática de atividade física no lazer e de intenção. As análises de sensibilidade indicaram que as tendências temporais de atividade física no lazer e de intenção são altamente sensíveis à influência do comportamento atual da pessoa sobre a sua intenção futura, ao tamanho do raio de percepção da pessoa e à proporção de locais em que a atividade física no lazer pode ser praticada. Considerações finais: O mapa conceitual e o modelo baseado em agentes se mostraram adequados para investigar a conformação e evolução de padrões populacionais de atividade física no lazer em adultos. A influência do comportamento da pessoa sobre a sua intenção, o tamanho do raio de percepção da pessoa e a proporção de locais em que a atividade física no lazer pode ser praticada são importantes determinantes da conformação e evolução dos padrões populacionais de atividade física no lazer entre adultos no modelo.
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INTRODUÇÃO - A obesidade é uma preocupação de saúde pública cada vez mais importante, em todo o mundo. A obesidade infantil, por sua vez, vem sendo associada a um alto risco de agravos infantis e de obesidade e doenças crônicas não transmissíveis na fase adulta. Admite-se que o início da vida seja um momento crítico e determinante para o risco do indivíduo desenvolver sobrepeso ou obesidade. Entretanto, não está definido se existe algum período de maior vulnerabilidade na fase pós-natal e qual seria o melhor marcador do crescimento da criança para indicar uma possível intervenção precoce que possa minimizar o risco de desenvolver excesso de peso ou obesidade. OBJETIVO - Analisar as relações existentes entre indicadores antropométricos de crescimento no primeiro ano de vida e o desenvolvimento de excesso de peso no início da idade escolar. MÉTODOS - Estudo de uma coorte histórica de uma unidade básica de saúde em São Paulo, Brasil. Os momentos analisados foram aos três, seis e doze meses e aos sete anos de idade. Avaliou-se a velocidade de crescimento e o crescimento alcançado durante o primeiro ano de vida frente aos desfechos: excesso de peso e obesidade aos sete anos de idade. As variáveis foram analisadas estatisticamente através do Coeficiente de Correlação de Pearson e das curvas ROC, além de terem sido estimadas a sensibilidade, a especificidade e o risco relativo. RESULTADOS - Os Coeficientes de Correlação de Pearson do ganho de peso por ganho de comprimento nos períodos de 0 a 3 meses, 0 a 6 meses e 0 a 12 meses foram, respectivamente, 0,23 (IC 95 por cento : 0,13 a 0,33), 0,29 (IC 95 por cento : 0,19 a 0,39) e 0,34 (IC 95 por cento : 0,24 a 0,43), todos significantes estatisticamente. Os Coeficientes de Correlação de Pearson do escore z do Índice de Massa Corpórea (IMC) para 3, 6 e 12 meses foram, respectivamente, 0,39 (IC 95 por cento : 0,29 a 0,48), 0,41 (IC 95 por cento : 0,32 a 0,50) e 0,42 (IC 95 por cento : 0,33 a 0,51). Para excesso de peso na idade escolar, a utilização do marcador escore z do IMC aos 12 meses maior que 0,49 apresentou sensibilidade de 68,29 por cento (IC 95 por cento : 59,3 por cento a 76,4 por cento ), especificidade de 63,51 por cento (IC 95 por cento : 56,6 por cento a 70,0 por cento ) e risco relativo estimado de 2,31 (IC 95 por cento : 1,69 a 3,17). Para obesidade, o mesmo marcador apresentou sensibilidade de 76,47 por cento (IC 95 por cento : 62,5 por cento a 87,2 por cento ), especificidade de 56,89 por cento (IC 95 por cento : 50,9 por cento a 62,7 por cento ) e risco relativo estimado de 3,49 (IC 95 por cento : 1,90 a 6,43). CONCLUSÕES - O primeiro trimestre de vida se revelou como sendo o período mais crítico, entre os estudados, para o desenvolvimento de sobrepeso ou obesidade no início da idade escolar. No entanto, o escore z do IMC acima de 0,49 aos 12 meses de vida se mostrou como o melhor marcador para esses dois desfechos.