Using quality models in software package selection

The growing importance of commercial off-the-shelf software packages requires adapting some software engineering practices, such as requirements elicitation and testing, to this emergent framework. Also, some specific new activities arise, among which selection of software packages plays a prominent role. All the methodologies that have been proposed recently for choosing software packages compare user requirements with the packages' capabilities. There are different types of requirements, such as managerial, political, and, of course, quality requirements. Quality requirements are often difficult to check. This is partly due to their nature, but there is another reason that can be mitigated, namely the lack of structured and widespread descriptions of package domains (that is, categories of software packages such as ERP systems, graphical or data structure libraries, and so on). This absence hampers the accurate description of software packages and the precise statement of quality requirements, and consequently overall package selection and confidence in the result of the process. Our methodology for building structured quality models helps solve this drawback.Peer ReviewedPostprint (published version

Transport Policies in Latin America

The issues of air pollution and traffic congestion in Latin America have been growing increasingly important since the end of the 20th century. The latter may help explain why several cities around the continent have tried different combination of public policies with vary-ing degrees of success. We describe the policies that outline the Latin American experience in this matter and hope to be a useful reference to subsequent research in the area.Transport policies, driving restrictions, public transport, air pollution, car use

International sorghum trade: United States beyond the Mexican dependency?

This research proposes the estimation of a partial equilibrium econometric and simulation international trade model for sorghum: United States and Mexico component. Sixteen equations were simultaneously estimated and validated as a system using seemingly unrelated regression. Results on parameter estimates agree with economic theory and a working model for simulation and forecast was obtained. Forecast scenarios suggest that the dependency of sorghum trade between US and Mexico will continue.Supply, Demand, NAFTA, International trade, Sorghum, International Relations/Trade,

Distributed Resources Shift Paradigms on Power System Design, Planning, and Operation: An Application of the GAP Model

Power systems have evolved following a century-old paradigm of planning and operating a grid based on large central generation plants connected to load centers through a transmission grid and distribution lines with radial flows. This paradigm is being challenged by the development and diffusion of modular generation and storage technologies. We use a novel approach to assess the sequencing and pacing of centralized, distributed, and off-grid electrification strategies by developing and employing the grid and access planning (GAP) model. GAP is a capacity expansion model to jointly assess operation and investment in utility-scale generation, transmission, distribution, and demand-side resources. This paper conceptually studies the investment and operation decisions for a power system with and without distributed resources. Contrary to the current practice, we find hybrid systems that pair grid connections with distributed energy resources (DERs) are the preferred mode of electricity supply for greenfield expansion under conservative reductions in photovoltaic panel (PV) and energy storage prices. We also find that when distributed PV and storage are employed in power system expansion, there are savings of 15%-20% mostly in capital deferment and reduced diesel use. Results show that enhanced financing mechanisms for DER PV and storage could enable 50%-60% of additional deployment and save 15 /MWh in system costs. These results have important implications to reform current utility business models in developed power systems and to guide the development of electrification strategies in underdeveloped grids

Factores que afectan el desempeño de los alumnos mexicanos en edad de educación secundaria. Un estudio dentro de la corriente de eficacia escolar

El presente estudio analiza las tres principales bases de datos disponibles, de pruebas estandarizadas aplicadas a alumnos en edad de educación secundaria, como lo son las pruebas nacionales del INEE, el EXANI I del CENEVAL y PISA de la OCDE. Todas ellas incluyen numerosas variables tanto de los antecedentes de los alumnos, como de la escuela y sus profesores. Gracias a ellas, utilizando modelos jerárquico-lineales, es posible identificar, cuantificar y jerarquizar los diferentes factores que afectan el desempeño académico. Los resultados encontrados en muchos casos son consistentes con lo indicado por la literatura internacional, más existen diferencias que deben resaltarse, en particular para la escuela particular

Efficiency and Foreign Ownership in Banking: An International Comparison

This paper estimates cost and profit efficiency for Latin American and the Caribbean banking sectors. This study also conducts a comparative analysis of the performance of foreign and domestic banks operating in these counties. Using a model proposed by Battese and Coelli (1995), a common cost and profit frontiers with country-specific environmental variables have been estimated for a panel of 427 banking firms from sixteen countries. The empirical analysis reveals the importance of the environmental variables in explaining the efficiency differences among countries. The results show that profit efficiency levels are well below those corresponding to cost efficiency, implying that the most important inefficiency is on the revenue side. The results further indicate that on average foreign banks are more efficient than domestic banks.Banking, efficiency, foreign ownership

A diplomatic view for research integrity

The difficulty of implementing scientific integrity on an international scale is not just a factual problem: it expresses an internal tension in the globalisation of science faced with the pluralism of disciplines, cultures and institutions. A divide is often drawn between scientific integrity, which should be universal, and research ethics, which are always specific because they are encumbered by cultural values. However, the irreducibility of cultural differences obliges us to leave behind an idealistic or sovereignist vision of scientific integrity: it rather indicates a difference in degree between ethics and integrity, which requires the deployment of diplomacy to collectively elaborate international rules in research

Neumonía necrotizante inducida por Escherichia coli extraintestinal patogénica (ExPEC) en felinos

La Escherichia coli extraintestinal patogénica (ExPEC) es una de las bacterias más comunes encontradas enel tracto gastrointestinal de humanos y animales. ExPEC se caracteriza por producir enfermedad en otrosórganos fuera del tracto gastrointestinal. Este grupo ha sido implicado en infecciones del tracto urinario,meningitis, septicemia y neumonía en humanos y animales. En este estudio se muestran las implicancias dedistintas ExPEC en el desarrollo de neumonía en un refugio para gatos, en donde mueren de manera abrupta13 de 35 gatos; y en un tigre recientemente destetado y transportado en una caja para un programa detelevisión. En todos los casos, se observa neumonía necrotizante y fibrinosa, con la presencia de coloniasbacterianas intralesionales. El cultivo y la tipificación de los genotipos de virulencia demuestran la presenciade factores que son comunes para estas bacterias, como son hemolisina D, papGI y papGIII y cnf-1. Comopatogenia, se propone que una vez inhalada la bacteria, la presencia de hemolisina y cnf-1 reduce larespuesta inflamatoria aguda en pulmón, bloqueando la llegada e induciendo muerte de neutrófilos,disparando además edema, necrosis e inflamación. Interesantemente, hemolisinas y cnf-1 son encontrados enExPEC aisladas de humanos que padecen infecciones del tracto urinario y otros sitios extraintestinales. Enconclusión, Las infecciones por ExPEC en felinos es una entidad emergente, que se caracteriza por eldesarrollo de neumonía necrotizante que es frecuentemente fatal, y que este agente tiene un potencialzoonótico debido a su similitud entre las bacterias aisladas en humanos y animales, sumado a la cercaníaentre ambas especies.  

Análisis de los resultados obtenidos en estudios de eficacia escolar en México, comparados con los de otros países

Gracias a la disponibilidad de información proveniente de evaluaciones estandarizadas de aplicación masiva, durante los últimos años se han generado importantes estudios acerca de eficacia escolar en México, utilizando tanto metodologías tradicionales, modelos jerárquico-lineales y otras innovadoras técnicas. La cantidad de resultados disponibles permite hacer una comparación entre estos productos de la investigación en eficacia escolar en México con los resultados internacionales. Para ello se toman varios meta-análisis internacionales como base. En general, los resultados obtenidos son consistentes con lo que indica el estado del conocimiento internacional, puntualizándose las diferencias