FIML estimation of an endogenous switching model for count data

We develop FIML code for estimating a Poisson Count data model with lognormal unobserved heterogeneity and an endogenous dummy variable as proposed by Terza (1998). Gauss-Hermite quadrature is used for calculating the log-likelihood and a -ml d0- method is employed. We present an example and discuss the problems found during the development of the code.

An analysis of fertility behaviour in Mexico

In the last few decades female permanent sterilization became the most used contraception method in Mexico. During this time the demand for short-term contraceptives fell consistently. The shift in the demand for contraceptives raises concerns among demographers that the timing of children may remain unchanged regardless of the observed reductions in period fertility rates. After presenting a brief discussion of the economic theory on fertility behaviour (Chapter 2) and introducing the reader to the main demographic issues of modem Mexico (Chapter 3), Chapter 4 assesses these ideas in the context of modelling the timing of a first child, using duration models as main analysis tool. Findings suggest that young cohorts of women are effectively delaying first birth relative to the experience of older generations. Chapter 5 reports a study of the determinants of completed fertility. Special attention is given to studying how characteristics such as religion and ethnic group affect the likelihood of transition from low to high order parities. An innovative Double-Hurdle count model is developed for the analysis. Findings indicate that education and Catholicism are associated with reductions in the likelihood of transition from parities lower than four to high order parities. Being an indigenous language speaker increases the odds of a large family. Chapter 6 enquires how fertility plans of young individuals who live in intact families (i.e., those where both biological parents are present) differ from fertility plans of young individuals who live in non-intact families. The role of family background in the formation of fertility plans is studied. Count data models are used in the analysis, including an innovative technique for estimating quantile regression for count data. Findings suggest that an absent father reduces planned fertility, especially when women have weak preferences towards children. Education decreases planned fertility if strong preferences towards children are felt

Cardiac fluid dynamics anticipates heart adaptation

Hemodynamic forces represent an epigenetic factor during heart development and are supposed to influence the pathology of the grown heart. Cardiac blood motion is characterized by a vortical dynamics, and it is common belief that the cardiac vortex has a role in disease progressions or regression. Here we provide a preliminary demonstration about the relevance of maladaptive intra-cardiac vortex dynamics in the geometrical adaptation of the dysfunctional heart. We employed an in vivo model of patients who present a stable normal heart function in virtue of the cardiac resynchronization therapy (CRT, bi-ventricular pace-maker) and who are expected to develop left ventricle remodeling if pace-maker was switched off. Intra-ventricular fluid dynamics is analyzed by echocardiography (Echo-PIV). Under normal conditions, the flow presents a longitudinal alignment of the intraventricular hemodynamic forces. When pacing is temporarily switched off, flow forces develop a misalignment hammering onto lateral walls, despite no other electro-mechanical change is noticed. Hemodynamic forces result to be the first event that evokes a physiological activity anticipating cardiac changes and could help in the prediction of longer term heart adaptations

Left ventricular pacing vector selection by novel echo-particle imaging velocimetry analysis for optimization of quadripolar cardiac resynchronization device: A case report

Background: The availability of pacing configurations offered by quadripolar left ventricular leads could improve patients\u2019 response to cardiac resynchronization therapy; however, the selection of an optimal setting remains a challenge. Echo-particle imaging velocimetry has shown that regional anomalies of synchrony/synergy of the left ventricle are related to the alteration, reduction, or suppression of the physiological intracavitary pressure gradients. These observations are also supported by several numerical models of the left ventricle that have shown the close relationship between wall motion abnormalities, change of intraventricular flow dynamics, and abnormal distribution of forces operating on the ventricular endocardium. Case presentation: A 73-year-old white man in New York Heart Association III functional class with an ejection fraction of 27.5 % did not improve after 1 month of cardiac resynchronization therapy. Five configurations were tested and settings were defined by optimizing intraventricular flow. After 6 months, he became New York Heart Association II class with left ventricular ejection fraction of 53.2 %. Conclusions: The abnormal dynamic of pressure gradients during the cardiac cycle, through biohumoral endocrine, autocrine, and paracrine transduction, may lead to structural changes of the myocardial walls with subsequent left ventricular remodeling. The echo-particle imaging velocimetry technique may be useful for elucidating the favorable effects of cardiac resynchronization therapy on intraventricular fluid dynamics and it could be used to identify appropriate pacing setting during acute echocardiographic optimization of left pacing vector

Changes in electrical activation modify the orientation of left ventricular flow momentum: novel observations using echocardiographic particle image velocimetry

Changes in electrical activation sequence are known to affect the timing of cardiac mechanical events. We aim to demonstrate that these also modify global properties of the intraventricular blood flow pattern. We also explore whether such global changes present a relationship with clinical outcome

Graduation evaluation of the BA in Physical Activity and Sports of the UABC: A comprehensive achievement

Con la intención de contar con información que permita retroalimentar el programa educativo de la Licenciatura en Actividad Física y Deportes de la Universidad Autónoma de Baja California se realizó un ejercicio de evaluación al egreso. A través de un enfoque de evaluación comprensiva se diseñaron dos instrumentos. El primero de ellos enfocado en identificar los conocimientos y habilidades profesionales de los egresados en concordancia con el currículum del programa educativo en cuestión, y, el otro, centrado en conocer las habilidades interpersonales relacionadas con un egreso exitoso de este nivel de estudios. Se muestran los resultados psicométricos de los instrumentos, así como los resultados generales de los participantes en los diferentes campus de la universidad. Se concluye la relevancia de los resultados como un insumo para procesos de planeación didáctica y mejora curricular de la Licenciatura en Actividad Física y Deportes; así como la importancia del enfoque de evaluación utilizado, el cual antepone la participación de la comunidad académica en la conformación de la información generada, así como los alcances y limitaciones de una evaluación de este tipoWith the intention of having information to support evaluation of the educational program of the Bachelor Degree on Physical Activity and Sports of the Autonomous University of Baja California an assessment exercise was performed at the end of the undergraduate education. Through a comprehensive evaluation approach, two instruments were designed. The first of them focused on identifying the knowledge and professional skills of the graduates in accordance with the curriculum of the educational program in question, and the other, focused on identifying the interpersonal skills related to a successful exit from this level of studies. The article shows psychometric results of the instruments, as well as the general results of the participants in the different campuses of the university. Conclusions addresses the relevance of the results as an input for didactic planning processes and curricular improvement of the Degree in Physical Activity and Sports. As well, the article addresses the importance of the evaluation approach used, which highlights the participation of the academic community in the formation of the information generated, as well as the scope and limitations of an evaluation of this typ

Fast Detection of Two Smenamide Family Members Using Molecular Networking.

Caribbean sponges of the genus Smenospongia are a prolific source of chlorinated secondary metabolites. The use of molecular networking as a powerful dereplication tool revealed in the metabolome of S. aurea two new members of the smenamide family, namely smenamide F (1) and G (2). The structure of smenamide F (1) and G (2) was determined by spectroscopic analysis (NMR, MS, ECD). The relative and the absolute configuration at C-13, C-15, and C-16 was determined on the basis of the conformational rigidity of a 1,3-disubstituted alkyl chain system (i.e., the C-12/C-18 segment of compound (1). Smenamide F (1) and G (2) were shown to exert a selective moderate antiproliferative activity against cancer cell lines MCF-7 and MDA-MB-231, while being inactive against MG-63

Monitoring of misalignment in low speed geared shafts with acoustic emission sensors

The most common condition monitoring method applied to rotating machines is vibration measurement, although recently it has been proposed that acoustic emission (AE) offers additional advantages in early fault detection and low speed rotation systems. Capturing the AE signals is conditioned by the severe attenuation with distance and the presence of material discontinuities between source and sensor, therefore measurement device placement is more important than in traditional accelerometry. In this study AE signals are measured in gearboxes at misalignment conditions for the revision of signal characteristics from the generated signal due to the interaction of shafts, bearings and gears. For this purpose, several tests are performed using combinations of speed and varying load, considering the effect of lubricating oil temperature. Fixed measurements are taken over the bench supports, and on-board, where the sensors are rotating with the shafts. In parallel to acoustic emission a vibration analysis is done in order to contrast and analyze differences between both technologies at different operation states. Acquired data is processed to obtain statistical parameters from measurements in order to verify the values and tendencies due to transient phenomena related to changes in speed and load. AE provides better results than vibration employing the same time domain condition indicators. On the contrary, vibration recognizes clearly the fault through frequency analysis.This work has been supported by project DPI2017-85390-P funded by the Spanish Ministry of Science and Technology and RM16-XX012 PredictEA project funded by SODERCAN

Evaluación de actividades de investigación y posgrado. Una experiencia bajo un modelo comprensivo

This article focuses on the development of a proposal for the academic evaluation in higher education. Based on the institutional need of the Autonomous University of Baja California (UABC), Mexico, we developed an evaluation mechanism for its academic staff in their research and postgraduate activities, focused on offering feedback to improve academic work. Considering the need to take into account more robust indicators than scientific productivity by itself, we decided to use the comprehensive evaluation model to define the evaluation areas, based on the experience and needs of the community. Through the participation of 579 academics based on an open survey, the categories and indicators to be evaluated were defined, which are intended to reflect the demands of the particular context of the participating academics. We performed an inductive content analysis of the responses obtained; derived from this, we defined an evaluation mechanism that suggests the use of three instruments: Self-assessment guide; interview guide; and, Questionnaire for students. Each instrument was reviewed by experts from the university community to assess its possibility of application in all university areas. As a result, we obtained a proposal for an evaluation mechanism based on collegiality, thus coinciding with the comprehensive perspective, which aims to reflect the diversity of the university community and the complexity involved in carrying out academic activities in the field of postgraduate and research.El presente artículo se centra en el desarrollo de una propuesta para el problema de evaluación académica en educación superior. A partir de la necesidad institucional de la Universidad Autónoma de Baja California (UABC), México, se desarrolló un mecanismo de evaluación para su personal académico en sus actividades de investigación y posgrado, enfocado en ofrecer retroalimentación para la mejora de las labores académicas. Considerando la necesidad de tomar en cuenta indicadores más robustos que la sola productividad científica, se decidió utilizar el modelo de evaluación comprensiva para definir las áreas de evaluación a partir de la experiencia y necesidades de la comunidad universitaria. A través de la participación de 579 académicos a partir de una encuesta abierta, se definieron las categorías por evaluar, mismas que pretenden reflejar las demandas del contexto particular de los académicos participantes. Se realizó un análisis de contenido inductivo de las respuestas obtenidas; derivado de ello se definió un mecanismo de evaluación que sugiere el uso de tres instrumentos: Guía de autoevaluación; Guía de entrevista; y, Cuestionario para estudiantes. Cada instrumento se sujetó a revisión de expertos de la propia comunidad universitaria para valorar su pertinencia de aplicación para las diferentes áreas de conocimiento. Como resultado, se obtuvo una propuesta de mecanismo de evaluación basada en la colegialidad y no en estándares, coincidiendo así con la perspectiva comprensiva, la cual pretende reflejar la diversidad de la comunidad universitaria y la complejidad que implica la realización de actividades académicas en el ámbito del posgrado y la investigación

Análisis de información y agenda en periódicos digitales

Los profesionales de los medios de comunicación, en particular de la prensa plana homogenizan la pluralidad de las demandas públicas. Lo anterior incide en la construcción de la agenda del medio de comunicación e implica un sesgo en la selección, procesamiento y jerarquización de las informaciones a socializar. Se plantea como objetivo: analizar la información del periódico Vanguardia (Cuba) a partir del uso de indicadores bibliométricos. Se identificó que el diseño de la agenda mediática en el periódico analizado no se corresponde con la agenda pública del territorio donde está enmarcado. Tal situación actúa en detrimento de la representación de las problemáticas desde los medios de comunicación y por ende su visibilidad ante autoridades gubernamentales y decisores que pueden contribuir a solucionarlas