Design and implementation of real-time seamless display

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1999.Includes bibliographical references (p. 49).by Ivan Gonzalez-Gallo.M.Eng

Aportes de la psicometría al ejercicio profesional e investigativo en ciencias de la salud

La psicometría es una disciplina cuyo fin es la construcción de pruebas que miden y evalúan rasgos y variables psicológicas teniendo como método principal la estadística y las funciones matemáticas (1). Se articula dentro del ejercicio científico entendido como una práctica, es decir, sirve como soporte para los fines de la aplicación científica en cuanto a su funcionalidad mediante la creación de instrumentos necesarios para el alcance de los objetivos de la ciencia. La primera teoría psicométrica que aún se utiliza dentro de los modelos de medición y evaluación psicológica actuales, la Teoría Clásica de los Tests, fue constituida a principios del siglo pasado, y en la segunda mitad de éste surgieron nuevas teorías que intentaban responder algunas preguntas cuyas respuestas superan el alcance de la primera (p.e. la Teoría de Respuesta al Ítem). Esto hace que, en la actualidad, la Psicometría sea un vasto conglomerado de métodos y técnicas que en la práctica sirven para recolectar un determinado número de datos empíricos acerca del rendimiento, el desempeño, la cantidad o el valor categórico de un grupo o individuo dentro de un contexto particular con el fin de contrastarlo con un constructo teórico específico, construyendo instrumentos que permiten ordenar dichos datos, calibrarlos y minimizar los errores de medición del rasgo en cuestión. En la práctica, esto es en sí mismo un proceso de investigación continua, pues estos procesos se realizan en muestras poblacionales y los instrumentos deben revisarse con cierta periodicidad, ajustándose a nuevas muestras a través del tiempo y en diferentes lugares geográficos

Representaciones sociales asociadas al consumo de servicios funerarios en la ciudad de Bogotá, D. C.

Las empresas de servicios funerarios en la ciudad de Bogotá, se encuentran en un proceso de transición en cuanto a su estrategia de mercadeo, con el objetivo de cambiar el concepto de la prestación de servicios funerarios tradicional por el de “homenajes” a los seres fallecidos. Su finalidad es generar un contacto más cercano de los familiares con sus difuntos, desde una mirada menos dolorosa. Debido a ello, se realizó una investigación con enfoque cualitativo, en la que se identificaron las principales representaciones sociales asociadas a los significados de duelo y muerte (tanto en sus componentes nucleares como periféricos) y se documentaron los principales significados asociados a la categoría “amor” en la muestra entrevistada. De esta manera se identifica una serie de categorías que podrían ser útiles para el mejoramiento de las estrategias de mercadeo de dichas empresas. Se discuten posibles sesgos y se dan recomendaciones para futuras investigaciones

Contribuições da psicometria para a prática profissional e investigativa em ciências da saúde

La psicometría es una disciplina cuyo fin es la construcción de pruebas que miden y evalúan rasgos y variables psicológicas teniendo como método principal la estadística y las funciones matemáticas (1). Se articula dentro del ejercicio científico entendido como una práctica, es decir, sirve como soporte para los fines de la aplicación científica en cuanto a su funcionalidad mediante la creación de instrumentos necesarios para el alcance de los objetivos de la ciencia. La primera teoría psicométrica que aún se utiliza dentro de los modelos de medición y evaluación psicológica actuales, la Teoría Clásica de los Tests, fue constituida a principios del siglo pasado, y en la segunda mitad de éste surgieron nuevas teorías que intentaban responder algunas preguntas cuyas respuestas superan el alcance de la primera (p.e. la Teoría de Respuesta al Ítem). Esto hace que, en la actualidad, la Psicometría sea un vasto conglomerado de métodos y técnicas que en la práctica sirven para recolectar un determinado número de datos empíricos acerca del rendimiento, el desempeño, la cantidad o el valor categórico de un grupo o individuo dentro de un contexto particular con el fin de contrastarlo con un constructo teórico específico, construyendo instrumentos que permiten ordenar dichos datos, calibrarlos y minimizar los errores de medición del rasgo en cuestión. En la práctica, esto es en sí mismo un proceso de investigación continua, pues estos procesos se realizan en muestras poblacionales y los instrumentos deben revisarse con cierta periodicidad, ajustándose a nuevas muestras a través del tiempo y en diferentes lugares geográficos.Psychometrics is a discipline whose purpose is the construction of tests that measure and evaluate psychological traits and variables, with statistics and mathematical functions as the main method (1). It is articulated within the scientific exercise understood as a practice, that is, it serves as a support for the purposes of scientific application in terms of its functionality by creating the necessary instruments to achieve the objectives of science. The first psychometric theory that is still used within current psychological measurement and evaluation models, the Classical Theory of Tests, was constituted at the beginning of the last century, and in the second half of this new theories arose that tried to answer some questions whose responses are beyond the scope of the first (eg Item Response Theory). This means that, at present, Psychometry is a vast conglomeration of methods and techniques that in practice serve to collect a certain number of empirical data about the performance, performance, quantity or categorical value of a group or individual within of a particular context in order to contrast it with a specific theoretical construct, building instruments that allow ordering said data, calibrating it and minimizing measurement errors of the trait in question. In practice, this is in itself a continuous research process, since these processes are carried out in population samples and the instruments must be reviewed with certain periodicity, adjusting to new samples over time and in different geographical locations

Sensation seeking and psychoactive substance consumption: differences between a consumer and a non-consumer sample

Introducción. En varios países se han realizado numerosos estudios para demostrar la relación entre un alto nivel de búsqueda de sensaciones y el abuso de drogas ilícitas. Sin embargo, pocos estudios en Colombia reproducen dichos resultados. El objetivo de este estudio es examinar las diferencias del rasgo de la personalidad conocido como “búsqueda de sensaciones” y sus subescalas relacionadas con el abuso de drogas en dos muestras en Colombia, consumidores y no consumidores, las cuales se medirán por medio de la metodología de escala de búsqueda de sensaciones (forma V). Metodología. La muestra se compone de 341 sujetos adultos, de ambos sexos. La mitad de ellos fueron consumidores de drogas ilícitas y la otra mitad fueron no consumidores; estos grupos se evaluaron por medio de los resultados de la escala de búsqueda de sensaciones (forma V). Resultados. Existe una diferencia significativa entre los consumidores y no consumidores en la escala general del rasgo y en tres subescalas (búsqueda de emociones y aventura, búsqueda de experiencias y desinhibición). Discusión. Las diferencias entre los puntajes de los consumidores y no consumidores con respecto al rasgo general y los subrasgos demuestran la importancia de los factores de personalidad en el abuso de sustancias, pese a que los factores sociales y de aprendizaje también influyen en esto. Conclusiones. Existe una relación entre la búsqueda de sensaciones y el abuso de sustancias, lo que demuestra la importancia del nivel del rasgo en el fenómeno multivariante de la dependencia de sustancias.Introduction. Internationally, there have been several studies carried out in order to demonstrate the relationship between a high level of Sensation Seeking and illegal drug abuse. However, few studies in Colombia replicate those results. The objective is to examine the difference of Sensation Seeking personality trait and its subscales in the behaviour of drug abuse on two Colombian samples, consumers and non-consumers, measured through the Sensation Seeking Scale-V (Zuckerman & Kulhman, 1980). Methodology. 341 adult subjects, from both genders, composed the sample, half of them were consumers of illegal drugs and half of them non-consumers, assessed through Sensation Seeking Scale Version V. Results. There is a significant difference between consumers and non-consumers within the general scale and three subscales of the trait (Thrill and Adventure Seeking, Experience Seeking and Disinhibition). Discussion. Differences between the scores of consumers and non-consumers sample regarding the general trait and subtraits show the relevance of personality factors regarding substance abuse, independently than social and learning factors are influential as well. Conclusions. There is a link between Sensation Seeking and substance abuse showing the importance of the level of the trait in the multivariate phenomenon of substance dependence

Paradoxes of the environmental behavior of university students in different academic disciplines

The objective of the present study was to establish the characteristics of the pro environmental behavior of Colombian university students; that is, to identify the attitudes, beliefs, valuations, practices and environmental knowledge of Colombian students from different university careers. For this purpose, a cross-sectional descriptive-correlational study was carried out with a sample of 1503 students from different university careers in five Colombian cities, with an incidence probability of .5, 95 % confidence and an error of 2.5 %. The participants were randomly selected within each university and the questionnaires applied were the Pro environmental Behaviour Inventory (ICP) and the Environmental Knowledge Test (TCA); the latter was developed specifically for the purposes of this research. The students surveyed were found to have positive environmental attitudes and beliefs in most dimensions. The level of environmental awareness of students in the five selected cities is low. Although no significant differences were observed between the careers with respect to beliefs, valuations, actions and environmental knowledge, paradoxically the students of environmental sciences occupied inferior places to those who study economic and administrative sciences. Thus, in the analysis of specific items it was evidenced that the students of environmental sciences develop diverse anti environmental actions, in a similar way to the behavior patterns of the students of the other researched careers. With respect to the region, the results show that it is possible to conclude that there are differences according to the city with respect to the beliefs, valuation, knowledge and environmental actions of the students surveyed. Among the findings it is worth highlighting the results of Bucaramanga in terms of the report of environmental actions and the highest average in the TCA observed in that city. Similarly, Cali stands out along with Bucaramanga in its results, while Medellín obtained the lowest scores in environmental knowledge. Finally, in the report on environmental actions in university students, contradictory results are observed, given that it presents a controversial profile because people perform pro-environmental and anti-environmental behaviors at the same time, with positive environmental attitudes and beliefs in accordance with these attitudes. Regarding the knowledge about the environment, in the descriptive results the average of the test was 12 points, which means that the students failed the test. The multivariate analysis showed that the theoretical model on which the construction of the ICP was based and the instruments from which items were selected for its conformation, apparently has great predictive power with respect to the verbal report of environmental actions; however, the TCA, a test constructed specifically for this research, would covariate with almost all the factors of the ICP but does not predict causally the actions reported by the students. In general, this study shows that university institutions and the Colombian government have the challenge of ensuring that environmental education achieves the expected results for the fulfillment of both the country and the world’s environmental goals. The results also demonstrates the need to articulate policies, actions and regulations to improve the quality of environmental education in universities, as well as to implement citizen behavior programs that promote responsible consumption, given that knowledge does not correlate with effective actions in terms of public services, green brands and solid urban waste management, among other areas.El objetivo del presente estudio fue establecer las características del comportamiento proambiental de los estudiantes universitarios colombianos, esto es, identificar las actitudes, creencias, valoraciones, prácticas y conocimientos ambientales de estudiantes colombianos de diferentes carreras universitarias. Para ello se realizó un estudio descriptivo-correlacional de corte transversal con una muestra de 1503 estudiantes de diferentes carreras universitarias en cinco ciudades colombianas, con una probabilidad de incidencia de .5, 95 % de confianza y un error del 2.5 %. Los participantes fueron seleccionados aleatoriamente al interior de cada universidad y se les aplicaron el Inventario de Comportamiento Proambiental (ICP) y el Test de Conocimiento Ambiental (TCA), este último desarrollado específicamente para propósitos de la presente investigación. Se encontró que los estudiantes encuestados poseen actitudes y creencias ambientales positivas en la mayoría de las dimensiones. El nivel de conocimiento ambiental de los estudiantes en las cinco ciudades seleccionadas es bajo. Si bien no se observaron diferencias significativas entre las carreras respecto a las creencias, valoraciones, acciones y conocimientos ambientales, paradójicamente los estudiantes de ciencias ambientales ocuparon lugares inferiores a los que estudian ciencias económicas y administrativas. Se puede concluir que existen diferencias según la ciudad en las creencias, valoración, conocimiento y acciones ambientales de los estudiantes encuestados. El reporte de acciones ambientales presenta un perfil controversial pues al mismo tiempo las personas realizan comportamientos proambientales y antiambientales. Las instituciones universitarias y el gobierno tienen el desafío de lograr que la educación ambiental muestre los resultados esperados para el cumplimiento de las metas ambientales del país y del mundo

Average daily ischemic versus bleeding risk in patients with ACS undergoing PCI: Insights from the BleeMACS and RENAMI registries

Background: The risk of recurrent ischemia and bleeding after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) may vary during the first year of follow-up according to clinical presentation, and medical and interventional strategies. Methods: BleeMACS and RENAMI are 2 multicenter registries enrolling patients with ACS treated with PCI and clopidogrel, prasugrel, or ticagrelor. The average daily ischemic and bleeding risks (ADIR and ADBR) in the first year after PCI were the primary end points. The difference between ADBR and ADIR was calculated to estimate the potential excess of bleeding/ischemic events in a given period or specific subgroup. Results: A total of 19,826 patients were included. Overall, in the first year after PCI, the ADBR was 0.008085%, whereas ADIR was 0.008017% (P =.886). In the first 2 weeks ADIR was higher than ADBR (P =.013), especially in patients with ST-segment elevation myocardial infarction or incomplete revascularization. ADIR continued to be, albeit non-significantly, greater than ADBR up to the third month, whereas ADBR became higher, although not significantly, afterward. Patients with incomplete revascularization had an excess in ischemic risk (P =.003), whereas non–ST-segment elevation ACS patients and those on ticagrelor had an excess of bleeding (P =.012 and P =.022, respectively). Conclusions: In unselected ACS patients, ADIR and ADBR occurred at similar rates within 1 year after PCI. ADIR was greater than ADBR in the first 2 weeks, especially in ST-segment elevation myocardial infarction patients and those with incomplete revascularization. In the first year, ADIR was higher than ADBR in patients with incomplete revascularization, whereas ADBR was higher in non–ST-segment elevation ACS patients and in those discharged on ticagrelor

Gene geography of Chile. Regional distribution of American, European and African genetic contributions

Background: The geographical distribution of genes plays a key role in genetic epidemiology. The Chilean population has three major stem groups (Native American, European and African). Aim: To estimate the regional rate of American, European and African admixture of the Chilean population. Subjects and Methods: Forty single nucleotide polymorphisms (SNP´s) which exhibit substantially different frequencies between Amerindian populations (ancestryinformative markers or AIM´s), were genotyped in a sample of 923 Chilean participants to estimate individual genetic ancestry. Results: The American, European and African individual average admixture estimates for the 15 Chilean Regions were relatively homogeneous and not statistically different. However, higher American components were found in northern and southern Chile and higher European components were found in central Chile. A negative correlation between African admixture and latitude was observed. On the average, American and European genetic contributions were similar and significantly higher than the African contribution. Weighted mean American, European and African genetic contributions of 44.34% ± 3 9%, 51.85% ± 5.44% and 3.81% ± 0 .45%, were estimated. Fifty two percent of subjects harbor African genes. Individuals with Aymara and Mapuche surnames have an American admixture of 58.64% and 68.33%, respectively. Conclusions: Half of the Chilean population harbors African genes. Participants with Aymara and Mapuche surnames had a higher American genetic contribution than the general Chilean population. These results confirm the usefulness of surnames as a first approximation to determine genetic ancestr

Gene geography of Chile. Regional distribution of American, European and African genetic contributions

Artículo de publicación SciELOBackground: The geographical distribution of genes plays a key role in genetic epidemiology. The Chilean population has three major stem groups (Native American, European and African). Aim: To estimate the regional rate of American, European and African admixture of the Chilean population. Subjects and Methods: Forty single nucleotide polymorphisms (SNP´s) which exhibit substantially different frequencies between Amerindian populations (ancestryinformative markers or AIM´s), were genotyped in a sample of 923 Chilean participants to estimate individual genetic ancestry. Results: The American, European and African individual average admixture estimates for the 15 Chilean Regions were relatively homogeneous and not statistically different. However, higher American components were found in northern and southern Chile and higher European components were found in central Chile. A negative correlation between African admixture and latitude was observed. On the average, American and European genetic contributions were similar and significantly higher than the African contribution. Weighted mean American, European and African genetic contributions of 44.34% ± 3 9%, 51.85% ± 5.44% and 3.81% ± 0 .45%, were estimated. Fifty two percent of subjects harbor African genes. Individuals with Aymara and Mapuche surnames have an American admixture of 58.64% and 68.33%, respectively. Conclusions: Half of the Chilean population harbors African genes. Participants with Aymara and Mapuche surnames had a higher American genetic contribution than the general Chilean population. These results confirm the usefulness of surnames as a first approximation to determine genetic ancestry.Trabajo financiado por proyecto Network for Study of Latin American Populations