Relationship between the morphology of the maxillary central incisor and horizontal and vertical measurements of the face

Purpose: In order to assist in the selection of artificial teeth for complete dentures, this study aimed to assess the relationship between horizontal and vertical measurements of the face and the morphology of the maxillary central incisor. Materials and Methods: This was a study of 50 plaster casts and 100 teleradiographs - 50 in lateral norm and 50 in frontal norm, belonging to 50 individuals, Caucasian, with a naturally optimal occlusion, matching at least four of the six keys of Andrews. Images of the upper central incisors were obtained by scanning the plaster casts (three-dimensional) and subjectively classified by three examiners as oval, triangular or quadrangular. Facial measures (vertical and horizontal) were defined by means of teleradiographs. In order to check inter-examiner agreement on the classification of central incisor, the Kappa test was used. To verify whether data had normal distribution, the Kolmogorov-Smirnov test was used ( P > 0.2) was used. One-way analysis of variance was employed to assess the association between variables (P > 0.05). Results: When vertical measurements were compared with the three incisor shapes, there was no statistically significant difference (P > 0.05): Triangular (0.54), oval (0.63) and quadrangular (0.51). Similarly, no difference (P > 0.05) was found for facial width (139.08, 143.37, 141.65), maxillary width (76.68, 78.99, 76.91) and mandibular width (103.47, 105.50, 103.11). Conclusions: The majority of cases showed that horizontal and vertical measurements of the face cannot be used as a reference for determining the morphology of the maxillary central incisor crown. It is relevant to analyze and compare other morphological structures to improve the oral health-related quality of life for the conventional denture wearer.

Alteração da impulsão vertical após o período competitivo em atletas de profissionais de futebol

Change on vertical jump after competitive period in professionals soccer players. Brazilian Journal of Biomotricity, v. 4, n. 2, p. 140-147, 2010. Soccer is a sport that demands different intensities of run, with decisive actions of a match being held in maximum intensity. Vertical jump test is widely used in soccer players due to the strong relationship with speed and agility. Futhermore, there are little information about change on vertical jump after the competitive season in soccer players. The aim of this study was to analyze change on vertical jump after the competitive season in professional soccer players. Took part in this study 21 male athletes (20.82 ± 3.16 years, 72.28 ± 8.74 kg and 179.91 ± 6.14 cm) subscribers to the 4th division of the Paulista championship of 2009. The competitive season had a duration of 20 weeks, with a total of 20 official matchs done. The test used was the counter-movement vertical jump (VJ), that was performed in the first (PRE) and last (POS) training session of the competitive period. After confirmation of data normality by Kolmogorov-Smirnov, the inferential analysis of the results of VJ between PRE and POS was performed using the paired t-test, considering the significance level of 5%. There was a significant increase (p<0,05) on VJ after the competitive period (PRE=54,19±4,46 and POS=57,94±5,23). According to the results of this study, it is possible to increase the performance of VJ in professional soccer players after the competitive period of 20 weeks duration.

Sistema baseado em regras fuzzy do tipo Takagi-Sugeno aplicado a ecos de radares meteorológicos

Pós-graduação em Ciências Ambientais - Sorocaba

Hipomineralização molar incisivo: qualidade de vida relacionada à saúde bucal e percepção estética em escolares de 8 a 12 anos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Fatores de risco relacionados à perda de produtividade laboral e aumento dos custos ambulatoriais de pacientes atendidos por unidades básicas de saúde

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Biomechanical and histologic evaluation of non-washed resorbable blasting media and alumina-blasted/acid-etched surfaces

Objectives: To compare the biomechanical fixation and histomorphometric parameters between two implant surfaces: non-washed resorbable blasting media (NWRBM) and alumina-blasted/acid-etched (AB/AE), in a dog model. Material and methods: The surface topography was assessed by scanning electron microscopy, optical interferometry and chemistry by X-ray photoelectron spectroscopy (XPS). Six beagle dogs of similar to 1.5 years of age were utilized and each animal received one implant of each surface per limb (distal radii sites). After a healing period of 3 weeks, the animals were euthanized and half of the implants were biomechanically tested (removal torque) and the other half was referred to nondecalcified histology processing. Histomorphometric analysis considered bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Following data normality check with the Kolmogorov-Smirnov test, statistical analysis was performed by paired t-tests at 95% level of significance. Results: Surface roughness parameters Sa (average surface roughness) and Sq (mean root square of the surface) were significantly lower for the NWRBM compared with AB/ AE. The XPS spectra revealed the presence of Ca and P in the NWRBM. While no significant differences were observed for both BIC and BAFO parameters (P>0.35 and P>0.11, respectively), a significantly higher level of torque was observed for the NWRBM group (P = 0.01). Bone morphology was similar between groups, which presented newly formed woven bone in proximity with the implant surfaces. Conclusion: A significant increase in early biomechanical fixation was observed for implants presenting the NWRBM surface.

STATISTICAL TEST FOR GENOTYPE AND ENVIRONMENT CONTRIBUTION IN THE GENOTYPES x ENVIRONMENTS INTERACTION MATRIX

The objective of the present work was to propose a method for testing the contribution of each level of the factors in a genotypes x environments (GxE) interaction using multi-environment trials analyses by means of an F test. The study evaluated a data set, with twenty genotypes and thirty-four environments, in a block design with four replications. The sum of squares within rows (genotypes) and columns (environments) of the GxE matrix was simulated, generating 10000 experiments to verify the empirical distribution. Results indicate a noncentral chi-square distribution for rows and columns of the GxE interaction matrix, which was also verified by the Kolmogorov-Smirnov test and Q-Q plot. Application of the F test identified the genotypes and environments that contributed the most to the GxE interaction. In this way, geneticists can select good genotypes in their studies.

Estimation of lung vital capacity before and after coronary artery bypass grafting surgery: a comparison of incentive spirometer and ventilometry

Abstract Background Measurement of vital capacity (VC) by spirometry is the most widely used technique for lung function evaluation, however, this form of assessment is costly and further investigation of other reliable methods at lower cost is necessary. Objective: To analyze the correlation between direct vital capacity measured with ventilometer and with incentive inspirometer in patients in pre and post cardiac surgery. Methodology Cross-sectional comparative study with patients undergoing cardiac surgery. Respiratory parameters were evaluated through the measurement of VC performed by ventilometer and inspirometer. To analyze data normality the Kolmogorov-Smirnov test was applied, for correlation the Pearson correlation coefficient was used and for comparison of variables in pre and post operative period Student's t test was adopted. We established a level of ignificance of 5%. Data was presented as an average, standard deviation and relative frequency when needed. The significance level was set at 5%. Results We studied 52 patients undergoing cardiac surgery, 20 patients in preoperative with VC-ventilometer: 32.95 ± 11.4 ml/kg and VC-inspirometer: 28.9 ± 11 ml/Kg, r = 0.7 p < 0.001. In the post operatory, 32 patients were evaluated with VC-ventilometer: 28.27 ± 12.48 ml/kg and VC-inspirometer: 26.98 ± 11 ml/Kg, r = 0.95 p < 0.001. Presenting a very high correlation between the evaluation forms studied. Conclusion There was a high correlation between DVC measures with ventilometer and incentive spirometer in pre and post CABG surgery. Despite this, arises the necessity of further studies to evaluate the repercussion of this method in lowering costs at hospitals.

SEM analysis and push-out bond strength of fiberglass posts luted with different cements of glass-ionomer in humid environment: pilot test

The objective of this study was to evaluate the push-out bond strength of fiberglass resin reinforced bonded with five ionomer cements. Also, the interface between cement and dentin was inspected by means of SEM. Fifty human canines were chose after rigorous scrutiny process, endodontically treated and divided randomly into five groups (n = 3) according to cement tested: Group I – Ionoseal (VOCO), Group II – Fugi I (GC), Group III – Fugi II Improved (GC), Group IV – Rely X Luting 2 (3M ESPE), Group V – Ketac Cem (3M ESPE). The post-space was prepared to receive a fiberglass post, which was tried before cementation process. No dentin or post surface pretreatment was carried out. After post bonding, all roots were cross-sectioned to acquire 3 thin-slices (1 mm) from three specific regions of tooth (cervical, medium and apical). A Universal test machine was used to carry out the push-out test with cross-head speed set to 0.5mm/mim. All failed specimens were observed under optical microscope to identify the failure mode. Representative specimens from each group was inspected under SEM. The data were analyzed by Kolmogorov-Smirnov and Levene’s tests and by two-way ANOVA, and Tukey’s port hoc test at a significance level of 5%. It was compared the images obtained for determination of types of failures more occurred in different levels. SEM inspection displayed that all cements filled the space between post and dentin, however, some imperfections such bubles and voids were noticed in all groups in some degree of extension. The push-out bond strength showed that cement Ketac Cem presented significant higher results when compared to the Ionoseal (P = 0.02). There were no statistical significant differences among other cements.

Analysis of surface hardness of artificially aged resin composites

This study evaluated the effect of artificially accelerated aging (AAA) on the surface hardness of eight composite resins: Filtek Z250, Filtek Supreme, 4 Seasons, Herculite, P60, Tetric Ceram, Charisma, and Filtek Z100. Sixteen specimens were made from the test piece of each material, using an 8.0 × 2.0 mm teflon matrix. After 24 hours, eight specimens from each material were submitted to three surface hardness readings using a Shimadzu Microhardness Tester for 5 seconds at a load of 50 gf. The other eight specimens remained in the artificially accelerated aging machine for 382 hours and were submitted to the same surface hardness analysis. The means of each test specimen were submitted to the Kolmogorov-Smirnov test (p > 0.05), ANOVA and Tukey test (p < 0.05). With regard to hardness (F = 86.74, p < 0.0001) the analysis showed significant differences among the resin composite brands. But aging did not influence the hardness of any of the resin composites (F = 0.39, p = 0.53). In this study, there was interaction between the resin composite brand and the aging factors (F = 4.51, p < 0.0002). It was concluded that notwithstanding the type of resin, AAA did not influence surface hardness. However, with regard to hardness there was a significant difference among the resin brands.

Stima della fecondità del lotto in una specie ittica a deposizione parziale (Engraulis encrasicolus): due aree a confronto, il Mar Tirreno e lo Stretto di Sicilia.

L'importanza dell'acciuga europea (Engraulis encrasicolus) come risorsa ittica, sia a livello economico che ecologico, nel Mar Mediterraneo, ha portato alla necessità di monitorare la biomassa deponente di questa specie per cercare di dare un limite al suo sovrasfruttamento (rappresentando il 22% delle catture nazionali). Lo studio effettuato riguarda le stime di fecondità dell'acciuga europea tramite l'applicazione di un metodo di analisi d'immagine, Whole Mount, su campioni di gonadi di adulti maturi e pronti alla deposizione. Il campionamento degli esemplari è avvenuto durante due campagne oceanografiche, organizzate dall'U.O.S di Capo Granitola dell'Istituto per l'Ambiente Marino Costiero del CNR, che hanno coperto l'area dello Stretto di Sicilia e del Mar Tirreno, durante i mesi estivi che rappresentano il picco di deposizione della specie. Nel presente lavoro sono stati analizzati in totale 76 ovari di acciuga, provenienti da entrambe le aree di campionamento e che presentassero ovociti maturi e risultassero, quindi, in una fase di deposizione nota come "deposizione imminente". Per entrambe le aree di studio è stata stimata una relazione lunghezza-peso con andamento esponenziale. I test statistici non parametrici di Kolmogorov-Smirnov e di Mann-Whitney hanno permesso di stimare se vi fossero differenze tra la fecondità, l'indice gonadosomatico (IGS) e il fattore di condizione (CF) nelle due aree, Stretto di Sicilia e piattaforma settentrionale siciliana. I valori di CF sono risultati significativamente differenti tra le due aree se valutati con il test di Kolmogorov-Smirnov, tuttavia tale differenza non è stata confermata dal test di Mann-Whitney. L'IGS e la fecondità, invece, sono risultati significativamente diversi nelle due aree per entrambi i test. Si può ipotizzare che valori di fecondità differenti nelle due aree, nonostante in entrambi i casi il campionamento sia avvenuto durante il picco di riproduzione della specie, possono essere dovuti alla variabilità dei fattori abiotici, quali temperature e nutrienti, differenti nello Stretto di Sicilia e nell'area lungo le coste settentrionali siciliane. Temperatura e nutrienti possono essere differenti, poiché vi è un diverso movimento delle masse d'acqua causato da correnti distinte nelle due aree. Conoscere la variabilità dei parametri riproduttivi di una specie di rilevanza commerciale così alta, come l'acciuga, rappresenta uno strumento fondamentale per scegliere le misure di gestione sostenibile degli stock più appropriate per aree differenti.

Integration of Truncated Distributions in Exponential Family with Simulation Models of Logistics and Supply Chain Management

Truncated distributions of the exponential family have great influence in the simulation models. This paper discusses the truncated Weibull distribution specifically. The truncation of the distribution is achieved by the Maximum Likelihood Estimation method or combined with the expectation and variance expressions. After the fitting of distribution, the goodness-of-fit tests (the Chi-Square test and the Kolmogorov-Smirnov test) are executed to rule out the rejected hypotheses. Finally the distributions are integrated in various simulation models, e. g. shipment consolidation model, to compare the influence of truncated and original versions of Weibull distribution on the model.

Development and testing of a procedure for systematically assigning gestational age for clinical and research use

A graphing method was developed and tested to estimate gestational ages pre-and postnatally in a consistent manner for epidemiological research and clinical purposes on feti/infants of women with few consistent prenatal estimators of gestational age. Each patient's available data was plotted on a single page graph to give a comprehensive overview of that patient. A hierarchical classification of gestational age determination was then applied in a systematic manner, and reasonable gestational age estimates were produced. The method was tested for validity and reliability on 50 women who had known dates for their last menstrual period or dates of conception, and multiple ultrasound examinations and other gestational age estimating measures. The feasibility of the procedure was then tested on 1223 low income women with few gestational age estimators. The graphing method proved to have high inter- and intrarater reliability. It was quick, easy to use, inexpensive, and did not require special equipment. The graphing method estimate of gestational age for each infant was tested against the last menstrual period gestational age estimate using paired t-Tests, F tests and the Kolmogorov-Smirnov test of similar populations, producing a 98 percent probability or better that the means and data populations were the same. Less than 5 percent of the infants' gestational ages were misclassified using the graphing method, much lower than the amount of misclassification produced by ultrasound or neonatal examination estimates. ^

Modelos de evolución de masas de pinus sylvestris l.

En el capítulo dedicado a la calidad de la estación, como primera etapa se realiza una exhaustiva revisión bibliográfica a partir de la cual se comprueba que los métodos más precisos para determinar esta calidad, en términos generales, son aquellos basados en la relación de la altura con la edad. En base a los datos que se encuentran disponibles y como fruto de esta revisión bibliográfica, se decide probar tres métodos: uno de ellos que estudia la evolución de la altura en función del diámetro (MEYER) y los otros dos en función de la edad (BAILEY y CLUTTER y GARCÍA). Para probar estos métodos, se utilizan datos de parcelas de producción distribuidas en los tres principales sistemas montañosos de España: Ibérico, Central y Pirenaico. El modelo de MEYER implica una clasificación previa de las parcelas en función de su clase de sitio y los ajustes se realizan para cada clase, con lo que se obtienen cuatro curvas polimórficas. La ecuación que describe este modelo es: H = 1.3 + s(1-e-bD) El modelo de BAILEY y CLUTTER genera también un sistema de curvas polimórficas y se genera a partir de la relación entre el 1og de la altura y la inversa de la edad: log H = a + b¡(1/AC) Este método implica una agrupación o estratificación de las parcelas en clases de sitio. Por último, se prueba el modelo de GARCÍA que se basa en una ecuación diferencial estocástica: dHc(t) = b(ac-Hc(t)) + a(t)dw(t) y se prueba la siguiente estructura paramétrica: a b c °"0 o *o H0 global 1 oca 1 g1obal 0.00 global 0.00 0.0 Posteriormente se hace un análisis de los residuos en que se aplica la prueba de Durbin-Watson que detecta la presencia de correlación serial. Se verifica la forma aproximada a un "cometa" en los residuos, lo que es frecuente en series de tiempo cuando la magnitud analizada (en nuestro caso, la altura dominante) se acumula en el tiempo. Esta prueba no es concluyente en el sentido de que no aclara que modelo es el más apropiado. Finalmente, se validan estos modelos utilizando datos de las parcelas de clara. Para esto se utiliza información de arboles tipo sometidos a análisis de tronco. Esta validación permite concluir que el modelo de GARCÍA es el que mejor explica la evolución del crecimiento en altura. En el capítulo dedicado a las distribuciones diamétricas, se pretende modelizar dichas distribuciones a través de variables de estado. Para esto, como primera etapa, se prueban para 45 parcelas y tres inventarios, las siguientes funciones: - Normal - Gamma - Ln de dos parámetros - Ln de tres parámetros - Beta I I - Wei bul 1 Mediante el uso de chi-cuadrado como estimador de la bondad del ajuste, se determina que la función de Weibull es la que mejor responde a la distribución diamétrica de nuestras parcelas. Posteriormente, se comprueba la bondad de dicho ajuste, mediante la prueba de Kolmogorov-Smirnov, el que determina que en el 99X de los casos, el ajuste es aceptable. Luego se procede a la recuperación de 1 os*parámetros de la función de Weibull; a, b y c. En esta etapa se estratifica la información y se realizan análisis de varianza (ANOVA) y pruebas de medias de TUKEY que dan como resultado el que se continúe trabajando por tratamiento y por inventario quedando la diferencia entre sitios absorbida por la altura dominante. Para la recuperación de los parámetros, se utilizan las variables de estado que definen a nuestras parcelas; edad, densidad, altura dominante, diámetro medio cuadrático y área basimétrica. El método seguido es la obtención de ecuaciones de regresión con las variables de estado como independientes para predecir los valores de los parámetros antes mencionados. Las ecuaciones se obtienen utilizando distintas vías (STEPWISE, ENTER y RSQUARE) lo que nos proporciona abundante material para efectuar la selección de éstas. La selección de las mejores ecuaciones se hace en base a dos estadísticos conocidos: - Coeficiente de determinación ajustado: R2 a - Cp de MALLOWS Estos elementos se tratan en forma conjunta considerando, además, que el número de parámetros esté en concordancia con el número de datos. El proceso de selección implica que se obtengan 36 ecuaciones de regresión que posteriormente se validan en dos sentidos. Por una parte, se calcula el valor de cada parámetro según la ecuación que le corresponda y se compara con el valor de los parámetros calculados en el ajuste de Weibull. Lo que se puede deducir de esta etapa es que la distorsión que sufren los parámetros al efectuar ecuaciones de regresión, es relativamente baja y la diferencia se produce debido a errores que se originan al realizar los modelos. Por otra parte, con las parcelas que se encuentren disponibles, se valida el modelo en el sentido de hacer el proceso inverso al anterior, es decir a partir de sus variables de estado, fácilmente medibles, se obtienen los valores de los parámetros que definen a la función de Weibull. Con esto se reconstruye la distribución diamétrica de cada función. Los resultados que se obtienen de esto indican que los ajustes son aceptables a un nivel del 1X en el caso de tres parcelas.

Evaluación del tiempo de reacción en velocistas con y sin discapacidad auditiva: aplicaciones para la inclusión

Este trabajo de investigación trata de aportar luz al estudio del tiempo de reacción (TR) en velocistas con y sin discapacidad auditiva desde las Ciencias del Deporte. El planteamiento del presente estudio surgió al cuestionarnos la existencia de las diferencias en cuanto al TR visual y auditivo aplicado a velocistas con y sin discapacidad auditiva, pensando en el desarrollo futuro de competiciones inclusivas entre ambos colectivos. Por ello, este estudio trata de resolver las dificultades que los velocistas con discapacidad se encuentran habitualmente en las competiciones. A priori, los atletas con discapacidad auditiva compiten en inferioridad de condiciones como consecuencia de una salida que no parece la más adecuada para ellos (desde los tacos, han de mirar hacia la pistola del juez o el movimiento de un rival). El documento se divide en tres partes. En la primera parte se realiza la pertinente revisión del marco teórico y justificación del estudio. La segunda parte se centra en los objetivos de la investigación, el material y el método, donde se muestran los resultados, discusión y conclusiones del estudio realizado, así como las limitaciones del presente trabajo y sus futuras líneas de investigación. La tercera parte corresponde a la bibliografía y la cuarta parte a los anexos. En la primera parte, presentamos el marco teórico compuesto por cinco capítulos organizan la fundamentación que hemos realizado como revisión sobre los aspectos más destacados del TR, determinado por las características de la tarea y otros factores que influyen en el TR como objeto de nuestro estudio. Después exponemos los principales aspectos estructurales y funcionales del sistema nervioso (SN) relacionados con el TR visual y auditivo. Tras ello se expone la realidad del deporte para personas con discapacidad auditiva, indagando en sus peculiaridades y criterios de elegibilidad que tiene ese colectivo dentro del ámbito deportivo. A continuación abordamos el estudio de la salida de velocidad en el atletismo, como aspecto clave que va a guiar nuestra investigación, especialmente los parámetros determinantes en la colocación de los tacos de salida para atletas con y sin discapacidad auditiva, la posición de salida y la propia colocación de los estímulos en dicha situación. Es la segunda parte se desarrolla el trabajo de investigación que tiene como objetivos estudiar los valores de TR visual simple manual, TR en salida de tacos y los tiempos de desplazamiento a los 10m y 20m de velocistas con y sin discapacidad auditiva, así como analizar las posibles diferencias en TR según posición y tipo de estímulo luminoso, respecto a ambos grupos de atletas. Como tercer objetivo de estudio se evalúa cualitativamente, por parte de los propios atletas, el dispositivo luminoso utilizado. La toma de datos de este estudio se llevó a cabo entre los meses de febrero y mayo del 2014, en el módulo de atletismo del Centro de Alto Rendimiento Joaquín Blume (Madrid), con dos grupos de estudio, uno de 9 velocistas con discapacidad auditiva (VDA), conformando éstos el 60% de toda la población en España, según el número de las licencias de la FEDS en la modalidad de atletismo (velocistas, pruebas de 100 y 200 m.l.), en el momento del estudio, y otro de 13 velocistas sin discapacidad (VsDA) que se presentaron de manera voluntaria con unos mismos criterios de inclusión para ambos grupos. Para la medición y el registro de los datos se utilizaron materiales como hoja de registro, Medidor de Tiempo de Reacción (MTR), tacos de salida, ReacTime®, dispositivo luminoso conectado a los tacos de salida, células fotoeléctricas, ordenador y software del ReacTime, y cámara de video. La metodología utilizada en este estudio fue de tipo correlacional, analizando los resultados del TR simple manual según vía sensitiva (visual y auditiva) entre los dos grupos de VDA y VsDA. También se estudiaron los TR desde la salida de tacos en función de la colocación del dispositivo luminoso (en el suelo y a 5 metros, vía visual) y pistola de salida atlética (vía auditiva) así como el tiempo de desplazamiento a los 10m (t10m) y 20m (t20m) de ambos grupos de velocistas. Finalmente, se desarrolló y llevó a cabo un cuestionario de evaluación por parte de los atletas VDA con el objetivo de conocer el grado de satisfacción después de haber realizado la serie de experimentos con el dispositivo luminoso y adaptado para sistemas de salida en la velocidad atlética. Con el objetivo de comprobar la viabilidad de la metodología descrita y probar en el contexto de análisis real el protocolo experimental, se realizó un estudio piloto con el fin de conocer las posibles diferencias del TR visual desde los tacos de salida en velocistas con discapacidad auditiva, usando para dicha salida un estímulo visual mediante un dispositivo luminoso coordinado con la señal sonora de salida (Soto-Rey, Pérez-Tejero, Rojo-González y Álvarez-Ortiz, 2015). En cuanto a los procedimientos estadísticos utilizados, con el fin de analizar la distribución de los datos y su normalidad, se aplicó la prueba de Kolmogorov-Smirnof, dicha prueba arrojó resultados de normalidad para todas las variables analizadas de las situaciones experimentales EA, EVsuelo y EV5m. Es por ello que en el presente trabajo de investigación se utilizó estadística paramétrica. Como medidas descriptivas, se calcularon el máximo, mínimo, media y la desviación estándar. En relación a las situaciones experimentales, para estudiar las posibles diferencias en las variables estudiadas dentro de cada grupo de velocistas (intragrupo) en la situación experimental 1 (MTR), se empleó una prueba T de Student para muestras independientes. En las situaciones experimentales 2, 3 y 4, para conocer las diferencias entre ambos grupos de velocistas en cada situación, se utilizó igualmente la prueba T para muestras independientes, mientras que un ANOVA simple (con post hoc Bonferroni) se utilizó para analizar las diferencias para cada grupo (VDA y VsDA) por situación experimental. Así mismo, se utilizó un ANOVA de medidas repetidas, donde el tipo de estímulo (situación experimental) fue la variable intra-grupo y el grupo de velocistas participantes (VDA y VsDA) la entre-grupo, realizándose esta prueba para evaluar en cada situación el TR, t1m0 y t20m y las interacciones entre las variables. Para el tratamiento estadístico fue utilizado el paquete estadístico SPSS 18.0 (Chicago, IL, EEUU). Los niveles de significación fueron establecidos para un ≤0.05, indicando el valor de p en cada caso. Uno de los aspectos más relevantes de este trabajo es la medición en diferentes situaciones, con instrumentación distinta y con situaciones experimentales distintas, del TR en velocistas con y sin discapacidad auditiva. Ello supuso el desarrollo de un diseño de investigación que respondió a las necesidades planteadas por los objetivos del estudio, así como el desarrollo de instrumentación específica (Rojo-Lacal, Soto-Rey, Pérez-Tejero y Rojo-González, 2014; Soto-Rey et al., 2015) y distintas situaciones experimentales que reprodujeran las condiciones de práctica y competición real de VsDA y VDA en las pruebas atléticas de velocidad, y más concretamente, en las salidas. El análisis estadístico mostró diferencias significativas entre los estímulos visuales y sonoros medidos con el MTR, siendo menor el TR ante el estímulo visual que ante el sonoro, tanto para los atletas con discapacidad auditiva como para los que no la presentaron (TR visual, 0.195 s ± 0.018 vs 0.197 s ± 0.022, p≤0.05; TR sonoro 0.230 s ± 0.016 vs 0.237 s ± 0.045, p≤0.05). Teniendo en cuenta los resultados según población objeto de estudio y situación experimental, se registraron diferencias significativas entre ambas poblaciones, VDA y VsDA, siendo más rápidos los VDA que VsDA en la situación experimental con el estímulo visual en el suelo (EVsuelo, 0.191 ±0.025 vs 0.210 ±0.025, p≤0.05, respectivamente) y los VsDA en la situación experimental con el estímulo auditivo (EA, 0.396 ±0.045 vs 0.174 ±0.021, p≤0.05), aunque sin diferencias entre ambos grupos en la situación experimental con el estímulo visual a 5m de los tacos de salida. Es de destacar que en el TR no hubo diferencias significativas entre EA para VsDA y EVsuelo para VDA. El ANOVA simple registró diferencias significativas en todas las situaciones experimentales dentro de cada grupo y para todas las variables, por lo que estadísticamente, las situaciones experimentales fueron diferentes entre sí. En relación al de ANOVA medidas repetidas, la prueba de esfericidad se mostró adecuada, existiendo diferencias significativas en las varianzas de los pares de medias: el valor de F indicó que existieron diferencias entre las diferentes situaciones experimentales en cuanto a TR, incluso cuando éstas se relacionaban con el factor discapacidad (factor interacción, p≤0,05). Por ello, queda patente que las situaciones son distintas entre sí, también teniendo en cuenta la discapacidad. El η2 (eta al cuadrado, tamaño del efecto, para la interacción) indica que el 91.7% de la variación se deben a las condiciones del estudio, y no al error (indicador de la generalización de los resultados del estudio). Por otro lado, la evaluación del dispositivo luminoso fue positiva en relación a la iluminación, comodidad de uso, ubicación, color, tamaño, adecuación del dispositivo y del equipamiento necesario para adaptar al sistema de salida. La totalidad de los atletas afirman rotundamente que el dispositivo luminoso favorecería la adaptación al sistema de salida atlética para permitir una competición inclusiva. Asimismo concluyen que el dispositivo luminoso favorecería el rendimiento o mejora de marca en la competición. La discusión de este estudio presenta justificación de las diferencias demostradas que el tipo de estímulo y su colocación son clave en el TR de esta prueba, por lo que podríamos argumentar la necesidad de contar con dispositivos luminosos para VDA a la hora de competir con VsDA en una misma prueba, inclusiva. El presente trabajo de investigación ha demostrado, aplicando el método científico, que el uso de estos dispositivos, en las condiciones técnicas y experimentales indicadas, permite el uso por parte del VDA, usando su mejor TR visual posible, que se muestra similar (ns) al TR auditivo de VsDA, lo que indica que, para competiciones inclusivas, la salida usando el semáforo (para VDA) y la salida habitual (estímulo sonoro) para VsDA, puede ser una solución equitativa en base a la evidencia demostrada en este estudio. De esta manera, y como referencia, indicar que la media de los TR de los velocistas en la final de los 100 m.l. en los Juegos Olímpicos de Londres 2012 fue de 0.162 ±0.015. De esta manera, creemos que estos parámetros sirven de referencia a técnicos deportivos, atletas y futuros trabajos de investigación. Las aplicaciones de este trabajo permitirán modificaciones y reflexiones en forma de apoyo al entrenamiento y la competición para el entrenador, o juez de salida en la competición que, creemos, es necesaria para proporcionar a este colectivo una atención adecuada en las salidas, especialmente en situaciones inclusivas de práctica. ABSTRACT This research aims to study of reaction time (RT) in sprinters with and without hearing impairment from the Sports Science perspective. The approach of this study came asking whether there were differences in the visual and auditory RT applied to sprinters with and without hearing impairment, thinking about the future development of inclusive competition between the two groups. Therefore, this study attempts to resolve the difficulties commonly founded by sprinters with hearing impairments during competitions. A priori, sprinters with hearing impairment would compete in a disadvantage situation as a result of the use of a staring signal not suitable for them (from the blocks, they have to look to the judge´s pistol or the movement of an opponent). The document is divided into three parts. In the first part of the review of relevant theoretical framework and justification of the study is presented. The second part focuses on the research objectives, material and method, where results, discussion and conclusions of the study, as well as the limitations of this study and future research are presented. The third part contains references and the fourth, annexes. In the first part, we present the theoretical framework consisting of five chapters, organizing the state of the art of RT, determined by the characteristics of the task and other factors that influence the RT as object of our study. Then we present the main structural and functional aspects of the nervous system associated with visual and auditory RT. After that, sport for people with hearing disabilities is presented, investigating its peculiarities and eligibility criteria is that group within the deaf sport. Finally, we discuss the theoretical foundation of the study of start speed in athletics as a key aspect that will guide our research, especially the determining parameters in placing the starting blocks for athletes with and without hearing impairment, the starting position and the actual placement of stimuli in such a situation. The second part of the research aims to study the values of simple manual visual RT, RT start from blocks and travel times up to 10m and 20m of sprinters with and without hearing impairment, and to analyze possible differences in RT as position and type of light stimulus with respect to both groups of athletes. The third objective of the study is to assess the pertinence of the lighting device developed and used in the study, in a qualitatively way by athletes themselves. Data collection for this study was carried out between February and May 2014, in the Athletics module at the High Performance Centre Joaquin Blume (Madrid) with the two study groups: 9 sprinters with hearing impairments(VDA, reaching 60% of the population in Spain, according to the number of licenses for athletics at FEDS: sprint, 100 and 200 m.l., at the time of the study), and another 13 sprinters without disability (VsDA) who voluntarily presented themselves, with same inclusion criteria for both groups. For measuring and data collection materials such as recording sheet, gauge reaction time (MTR), starting blocks, ReacTime®, luminous device connected to the starting blocks, photocells, computer and software ReacTime, and video camera were used. The methodology used in this study was correlational, analyzing the results of simple manual RT according sensory pathway (visual and auditory) between the two groups (VsDA and VDA). Also auditory and visual RT was studied depending the placement of the start light signal (on the ground and 5 meters, visual pathway) and athletic start gun signal (auditory pathway, conventional situation) and travel time up to 10m (t10m) and 20m (t20m) for both groups of sprinters. Finally, we developed and carried out an evaluation questionnaire for VDA athletes in order to determine the degree of satisfaction after completing the series of experiments with lighting device and adapted to start systems in athletic speed. In order to test the feasibility of the methodology described and tested in the context of real analysis of the experimental protocol, a pilot study in order to know the possible differences visual RT from the starting blocks in sprinters with hearing impairments was performed, to said output using a visual stimulus coordinated by a lighting device with sound output signal (Soto-Rey Perez-Tejero, Rojo-González y Álvarez-Ortiz, 2015). For the statistical procedures, in order to analyze the distribution of the data and their normality, Kolmogorov-Smirnov test was applied, this test yielded normal results for all variables analyzed during EA, EVsuelo and EV5m experimental situations. Parametric statistics were used in this research. As descriptive measures, the maximum, minimum, mean and standard deviation were calculated. In relation to experimental situations, to study possible differences in the variables studied in each group sprinters (intragroup) in the experimental situation 1 (MTR), a Student t test was used for independent samples. Under the experimental situations 2, 3 and 4, to know the differences between the two groups of sprinters in every situation, the T test for independent samples was used, while a simple ANOVA (with post hoc Bonferroni) was used to analyze differences for each group (VDA and VsDA) by experimental situation. Likewise, a repeated measures ANOVA, where the type of stimulus (experimental situation) was variable intra-group and participants sprinters group (VDA and VsDA) the variable between-group, was performed to assess each situation for RT, t10m and t20m, and also interactions between variables. For the statistical treatment SPSS 18.0 (Chicago, IL, USA) was used. Significance levels were set for  ≤0.05, indicating the value of p in each case. One of the most important aspects of this work is the measurement of RT in sprinters with and without hearing impairment in different situations, with different instrumentation and different experimental situations. This involved the development of a research design that responded to the needs raised by the study aims and the development of specific instrumentation (Rojo-Lacal, Soto-Rey Perez-Tejero and Rojo-Gonzalez, 2014; Soto-Rey et al., 2015) and different experimental situations to reproduce the conditions of practical and real competition VsDA and VDA in athletic sprints, and more specifically, at the start. Statistical analysis showed significant differences between the visual and sound stimuli measured by the MTR, with lower RT to the visual stimulus that for sound, both for athletes with hearing disabilities and for those without (visual RT, 0.195 s ± 0.018 s vs 0.197 ± 0.022, p≤0.05; sound RT 0.230 s ± 0.016 vs 0.237 s ± 0.045, p≤0.05). Considering the results according to study population and experimental situation, significant differences between the two populations, VDA and VsDA were found, being faster the VDA than VsDA in the experimental situation with the visual stimulus on the floor (EVsuelo, recorded 0.191 s ± 0.025 vs 0.210 s ± 0.025, p≤0.05, respectively) and VsDA in the experimental situation with the auditory stimulus (EA, 0.396 s ± 0.045 vs 0.174 s ± 0.021, p≤0.05), but no difference between groups in the experimental situation with the 5m visual stimulus to the starting blocks. It is noteworthy that no significant differences in EA and EVsuelo between VsDA to VDA, respectively, for RT. Simple ANOVA showed significant differences in all experimental situations within each group and for all variables, so statistically, the experimental situations were different. Regarding the repeated measures ANOVA, the sphericity test showed adequate, and there were significant differences in the variances of the pairs of means: the value of F indicated that there were differences between the different experimental situations regarding RT, even when they were related to the disability factor (factor interaction, p≤0.05). Therefore, it is clear that the situations were different from each other, also taking into account impairment. The η2 (eta squared, effect size, for interaction) indicates that 91.7% of the variation is due to the conditions of the study, not by error (as indicator of the generalization potential of the study results). On the other hand, evaluation of the light signal was positively related to lighting, ease of use, location, color, size, alignment device and equipment necessary to adapt the start system. All the athletes claim strongly in favor of the lighting device adaptation system to enable athletic competition inclusive. Also they concluded that light device would enhance performance or would decrease their RT during the competition. The discussion of this study justify the type of stimulus and the start light positioning as key to the RT performance, so that we could argue the need for lighting devices for VDA when competing against VsDA the same competition, inclusive. This research has demonstrated, applying the scientific method, that the use of these devices, techniques and given experimental conditions, allows the use of the VDA, using his best visual RT, shown similar (ns) auditory RT of VsDA, indicating that for inclusive competitions, the start signal using the light (for VDA) and the usual start (sound stimulus) to VsDA can be an equitable solution based on the evidence shown in this study. Thus, and as a reference, indicate that the average of the RT sprinters in the 100 m. final at the 2012 Summer Olympic Games was 0.162 s ± 0.015. Thus, we believe that these parameters become a reference to sports coaches, athletes and future research. Applications of this work will allow modifications and reflections in the form of support for training and competition for the coach, or judge, as we believe is necessary to provide adequate attention to VDA in speed starts, especially in inclusive practice situations.