Differences in perception of barriers in higher education and the completion of a degree among Latinos in the U.S.

Presented at the Society for Social Work and Research Conference, January 16, 2009, New Orleans, Louisiana

Perceptions of barriers to K-12 academic achievement among Latinos in the U.S.

Presented at the Society for Social Work and Research Conference, January 16-18, 2009, New Orleans, Louisiana

A simple and objective method for reproducible resting state network (RSN) detection in fMRI

Spatial Independent Component Analysis (ICA) decomposes the time by space functional MRI (fMRI) matrix into a set of 1-D basis time courses and their associated 3-D spatial maps that are optimized for mutual independence. When applied to resting state fMRI (rsfMRI), ICA produces several spatial independent components (ICs) that seem to have biological relevance - the so-called resting state networks (RSNs). The ICA problem is well posed when the true data generating process follows a linear mixture of ICs model in terms of the identifiability of the mixing matrix. However, the contrast function used for promoting mutual independence in ICA is dependent on the finite amount of observed data and is potentially non-convex with multiple local minima. Hence, each run of ICA could produce potentially different IC estimates even for the same data. One technique to deal with this run-to-run variability of ICA was proposed by Yang et al. (2008) in their algorithm RAICAR which allows for the selection of only those ICs that have a high run-to-run reproducibility. We propose an enhancement to the original RAICAR algorithm that enables us to assign reproducibility p-values to each IC and allows for an objective assessment of both within subject and across subjects reproducibility. We call the resulting algorithm RAICAR-N (N stands for null hypothesis test), and we have applied it to publicly available human rsfMRI data (http://www.nitrc.org). Our reproducibility analyses indicated that many of the published RSNs in rsfMRI literature are highly reproducible. However, we found several other RSNs that are highly reproducible but not frequently listed in the literature.Comment: 54 pages, 13 figure

SMART: A statistical framework for optimal design matrix generation with application to fMRI

The general linear model (GLM) is a well established tool for analyzing functional magnetic resonance imaging (fMRI) data. Most fMRI analyses via GLM proceed in a massively univariate fashion where the same design matrix is used for analyzing data from each voxel. A major limitation of this approach is the locally varying nature of signals of interest as well as associated confounds. This local variability results in a potentially large bias and uncontrolled increase in variance for the contrast of interest. The main contributions of this paper are two fold (1) We develop a statistical framework called SMART that enables estimation of an optimal design matrix while explicitly controlling the bias variance decomposition over a set of potential design matrices and (2) We develop and validate a numerical algorithm for computing optimal design matrices for general fMRI data sets. The implications of this framework include the ability to match optimally the magnitude of underlying signals to their true magnitudes while also matching the "null" signals to zero size thereby optimizing both the sensitivity and specificity of signal detection. By enabling the capture of multiple profiles of interest using a single contrast (as opposed to an F-test) in a way that optimizes for both bias and variance enables the passing of first level parameter estimates and their variances to the higher level for group analysis which is not possible using F-tests. We demonstrate the application of this approach to in vivo pharmacological fMRI data capturing the acute response to a drug infusion, to task-evoked, block design fMRI and to the estimation of a haemodynamic response function (HRF) response in event-related fMRI. Our framework is quite general and has potentially wide applicability to a variety of disciplines.Comment: 68 pages, 34 figure

Assessing emotional reactivity: psychometric properties of the Perth emotional reactivity scale and the development of a short form

The Perth Emotional Reactivity Scale (PERS) is a 30-item self-report measure of trait levels of emotional reactivity. In this article, we examine the psychometric properties of the PERS subscale and composite scores in an adult community sample (N = 428), and develop an 18-item short form of the measure (PERS–S). The PERS and PERS–S are designed to assess the typical ease of activation, intensity, and duration of one\u27s emotional responses, and do so for positive and negative emotions separately. Our confirmatory factor analyses supported that the PERS and PERS–S both had the same theoretically congruent factor structure, and that all subscale and composite scores displayed high internal consistency reliability. Correlations with scores from established measures of psychopathology and emotion regulation also supported the validity of PERS and PERS–S scores. Our data therefore suggest that the PERS–S subscale and composite scores retain the psychometric strengths of their longer PERS counterparts. We conclude that both forms of the measure have good utility. Clinical and research applications are discussed

Fear vs. Facts: Examining the Economic Impact of Undocumented Immigrants in the U.S.

Undocumented immigration has become a contentious issue in the U.S. over the past decade. Opponents of undocumented immigration have argued that undocumented immigrants are a social and financial burden to the U.S. which has led to the passage of drastic and costly policies. This paper examined existing state and national data and found that undocumented immigrants do contribute to the economies of federal, state, and local governments through taxes and can stimulate job growth, but the cost of providing law enforcement, health care, and education impacts federal, state, and local governments differently. At the federal level, undocumented immigrants tend to contribute more money in taxes than they consume in services, however, the net economic costs or benefits to state and local governments varies throughout the U.S

La corrupción en los diferentes niveles de gobierno en el estado peruano y sus implicancias

El propósito de la investigación es determinar cuáles son las implicancias de la corrupción perpetrada por los altos funcionarios en los diferentes niveles de gobierno en el Estado peruano, para ello se constituyó tres líneas de investigación, la primera, explicar la importancia de la organización, funciones y el rol del Estado peruano, la segunda, identificar las causas de la corrupción de los altos funcionarios en los diferentes niveles del Estado desde el año 1990 hasta 2006, y por último la tercera, explicar las implicancias que trae la corrupción de los altos funcionarios en el Estado peruano. El segundo capítulo de nuestra investigación, desarrollaremos el marco teórico del objeto de estudio, en tal sentido procedemos a analizar lo concerniente al Estado peruano y la importancia de su rol; las causas de la corrupción de altos funcionarios, y, finalmente, las implicancias que trae la corrupción de los altos funcionarios en nuestro país. Respecto al tercer capítulo, se desarrolló la parte de métodos y materiales, asimismo se estableció que la investigación de tipo descriptiva. Y finalmente se concluye, que las implicancias de la corrupción perpetrada por los altos funcionarios en los diferentes niveles de gobierno en el Estado peruano, perjudican al directamente a la ciudadanía en razón de que estas acciones repercuten en los aspectos económicos, políticos, jurídicos y sociales de nuestro país.The purpose of the investigation is to determine what are the implications of corruption perpetrated by senior officials at different levels of government in the Peruvian State, for this three lines of research were established, the first, to explain the importance of organization, functions and the role of the Peruvian State, the second, to identify the causes of corruption of senior officials at different levels of the State from 1990 to 2006, and finally the third, to explain the implications of corruption of senior officials in the Peruvian State. The second chapter of our research, we will develop the theoretical framework of the object of study, in this sense we proceed to analyze what concerns the Peruvian State and the importance of its role; the causes of the corruption of high officials, and, finally, the implications that the corruption of the high officials in our country brings. With respect to the third chapter, the part of methods and materials was developed, as well as the descriptive research was established. And finally, it is concluded that the implications of corruption perpetrated by high-level officials at different levels of government in the Peruvian State, directly harm the citizenry because these actions have an impact on the economic, political, legal and social aspects of our country.Tesi

Estudio del déficit habitacional en el barrio San Miguel del Tejar parroquia de Yaruquí (prov. Pichincha)

El presente estudio analiza el déficit habitacional en el barrio San Miguel del Tejar. Para esto ha sido necesario realizar un análisis de la situación socioeconómica y entorno del barrio, además de investigar el presupuesto de los hogares y núcleos para financiamiento de vivienda. El crecimiento constante de la población y la mala distribución del ingreso ha hecho que la vivienda propia sea un bien cada vez más escaso. Todos los habitantes del barrio deberían involucrarse de una forma proactiva, para buscar soluciones y construír una realidad distinta para acceder a una vivienda propia y digna. El esfuerzo constante de todos los sectores permitirá acercarnos a ese gran sueño colectivo que es el Buen Vivir. Mediante esta investigación se pretende brindar posibles soluciones al problema de déficit que sufre este barrio.This study analyzes the housing shortage in the San Miguel del Tejar. To this has been necessary to conduct an analysis of socioeconomic status and neighborhood environment, in addition to investigating the household budget and cores for home financing. The continued population growth and poor distribution of income has made home ownership is an increasingly scarce resource. Everyone in the neighborhood should be involved in a proactive manner, to seek solutions and build a different reality to access homeownership and decent. The constant effort of all sectors will approach that collective dream is the Good Life. Through this research is to provide solutions to the problem of deficits experienced by this neighborhood