Latin America: incorporating environmental factors into the measurement of production efficiency and technical change

Includes bibliography

Alleviation of the debt burden: historical experience and present need

Includes bibliography

Historical biogeography and cryptic diversity in the Callichthyinae (Siluriformes, Callichthyidae)

The family Callichthyidae, divided into the subfamilies Corydoradinae and Callichthyinae, contains more than 200 species of armoured catfishes distributed throughout the Neotropics, as well as fossil species dating from the Palaeocene. Both subfamilies are very widely distributed throughout the continent, with some species ranges extending across multiple hypothesized biogeographical barriers. Species with such vast geographical ranges could be made up of multiple cryptic populations that are genetically distinct and have diverged over time. Although relationships among Callichthyinae genera have been thoroughly investigated, the historical biogeography of the Callichthyinae and the presence of species complexes have yet to be examined. Furthermore, there is a lack of fossil-calibrated molecular phylogenies providing a time frame for the evolution of the Callichthyinae. Here, we present a novel molecular data set for all Callichthyinae genera composed of partial sequences of mitochondrial and nuclear markers. These data were used to construct a fossil-calibrated tree for the Callichthyinae and to reconstruct patterns of spatiotemporal evolution. All phylogenetic analyses [Bayesian, maximum likelihood and maximum parsimony (MP)] resulted in a single fully resolved and well-supported hypothesis for the Callichthyinae, where Dianema is the sister group of all the remaining genera. Results suggest that the ancestry of most Callichthyinae genera originated in the Amazonas basin, with a number of subsequent ancestral dispersal events between adjacent basins. High divergences in sequences and time were observed for several samples of Hoplosternum littorale, Megalechis picta and Callichthys callichthys, suggesting that these species may contain cryptic diversity. The results highlight the need for a taxonomic revision of species complexes within the Callichthyinae, which may reveal more diversity within this relatively species-poor lineage. © 2013 Blackwell Verlag GmbH.

Las mujeres y el cambio demográfico: estadísticas e indicadores = Women and demographic change: statistics and indicators

Analiza a traves del examen de las estadisticas e indicadores existentes, los cambios demograficos mas relevantes para el conocimiento de la situacion de la mujer que han tenido lugar durante el periodo 1950-1980.

La sustentabilidad ambiental del desarrollo y el cambio tecnológico en América Latina y el Caribe = The environmental sustainability of development and technological change in Latin America and the Caribbean

Incluye Bibliografía

Cycles of economic growth and structural change in Venezuela 1950- 1974

Paper presented at the LASA Association, 14-16 November 1975, San Francisco, California

Urban transport planning in a context of demographic, social, economic and technological change

Transport planning necessarily takes into account more than just the immediate time-frame. In the case of urban transport, planning needs to come up with solutions in regard to infrastructure which is expensive and may have a useful life extending over several decades. Therefore, planning must take note of economic, technological, social and demographic changes that influence trips undertaken.The purpose of this article is to explore some of the trends that may well be observed in upcoming decades. The article arrives at the conclusion that, in a period of considerable change and uncertainty, failure to take heed of recent trends may result in the construction of infrastructure that is not always the most appropriate and, what is more, that urban development militates against the efficient operation of public transport and, as a result, is likely to jeopardize the sustainability of cities in the long term.

Mineral loss and color change of enamel after bleaching and staining solutions combination

Pigments of food and beverages could affect dental bleaching efficacy. The aim of this investigation was to evaluate color change and mineral loss of tooth enamel as well as the influence of staining solutions normally used by adolescent patients undergoing home bleaching. Initial hardness and baseline color were measured on enamel blocks. Specimens were divided into five groups (n = 5): G1 (control) specimens were kept in artificial saliva throughout the experiment (3 weeks); G2 enamel was exposed to 10% carbamide peroxide for 6 h daily, and after this period, the teeth were cleaned and stored in artificial saliva until the next bleaching session; and G3, G4, and G5 received the same treatments as G2, but after bleaching, they were stored for 1 h in cola soft drink, melted chocolate, or red wine, respectively. Mineral loss was obtained by the percentage of hardness reduction, and color change was determined by the difference between the data obtained before and after treatments. Data were subjected to analysis of variance and Fisher's test (a = 0.05). G3 and G5 showed higher mineral loss (92.96 +/- 5.50 and 94.46 +/- 1.00, respectively) compared to the other groups (p = 0.05). G5 showed high-color change (9.34 +/- 2.90), whereas G1 presented lower color change (2.22 +/- 0.44) (p = 0.05). Acidic drinks cause mineral loss of the enamel, which could modify the surface and reduce staining resistance after bleaching. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)

Cerrado vegetation and global change: the role of functional types, resource availability and disturbance in regulating plant community responses to rising CO2 levels and climate warming

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)