[en] The object of this short contribution is to highlight briefly some of the areas of Tropical Haematology in which the use of radioisotopic techniques are likely to advance our basic knowledge of the pathophysiology and aetiology of anaemias in the tropics, thereby providing a better rational basis for their clinical management

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No abstract available

[en] The pattern shown by dasometric variables was analyzed with tree biomass to estimate it by using data from two tropical forests in Costa Rica. Four possible models that estimate biomass in tropical forests were identified through a bibliographic review. 907 trees with diameter at breast height (dbh) greater than 10 cm were evaluated. Dasometric variables (wood density, total height and dbh) were used to analyze their relationship with biomass in order to finding a model that could predict it. The dbh and density were used as independent variables in the final model. A segmented regression technique (due to the relationship between the dap and the total height with the transformed biomass variable) and weighted mean squares to solve the heterocedasticity problem were used to estimate this model. The statistical assumptions of a general linear regression were evaluated by the behavior of the residuals and other parametric tests. A coefficient of determination of 0.992 was obtained. A methodological approach was proposed to estimate biomass at a general level in forests

[en] Some physical properties of wetland soils are reviewed with reference to the tropical regions. The soils have a common feature periodic flooding during the year. They exhibit wide variability in mechanical composition in accordance with their genesis and location. Bulk densities range from 1.0 to 1.9 Mg m^-3 for mineral soils with moderate organic matter content and from about 0.02 to 0.2 Mg m^-3 for organic soils. Total porosities are generally high with dominance of micropores in organic and clayey wetland soils. Shrink-swell potential is also generally high in many of these wetland types with consequent problems of crack formation. Anaerobiosis condition is a common feature in wetland soils. Also carbon dioxide levels may be excessive for normal crop development. Water-retentivity has been found to be high to very high to in a number of tropical wetland soils of medium to fine texture. In some organic soils values of over 100% (mass basis) are not uncommon. In particular, a value of up to 3000% has been reported. Water infiltration and percolation are highly variable. The heat capacities are generally high with resultant reduced temperatures. Land use and management strategies are proferred in the light of the properties. (author). 44 refs, 9 tabs

[en] La Chola Reef is located at the easternmost sector of the Eastern Tropical Pacific. Branching corals of the genus Pocillopora ha dominate this coral formation of 11. The main goal of this study was to evaluate changes in coral cover over time, by comparing data collected in 2002 and 2013, implementing the chain transect methodology. Additionally, we generated an up-to-date map of this reef using field data collected with a GPS and present the first in-situ water temperature data. The reef exhibited a 20% coral cover decline during the study period, with associated increases in algal cover (mainly coralline algae). Total extension of the reef seems to have remained stable during the last 30 years. Besides the usual stressors commonly associated with limitations in coral reef development in this region of the Pacific, seasonal decreases in temperature are proposed as a potential cause of coral cover loss on the deeper sectors of the reef.

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No abstract available

[en] Studies designed to evaluate the publication and research trends of Third World countries in areas related to cattle reproduction in the tropics have shown a marked tendency for publication in such forms as national journals, proceedings, annual reports and theses, which are not readily available for evaluation and assimilation by the scientific community in general. This, coupled with the fact that reports are published preferentially in the native language of the country concerned, contributes to the limited impact of these studies at international level. In addition, research is concentrated on topics which require relatively simple methods important for establishing local reproductive parameters. With regard to the publication output of researchers, it was found that the majority publish only one document, with less than 3% producing more than ten, over a 15 year period. On average, researchers publish over a period of less than five years, indicating a lack of continuity in the research effort in this field. A detailed analysis of the research carried out in Mexico revealed a considerable degree of repetition of studies, as well as the publishing of duplicate results. (author). 14 refs, 1 fig., 4 tabs

[en] Our paper examines the impact of the dynamical core on the simulation of tropical cyclone (TC) frequency, distribution, and intensity. The dynamical core, the central fluid flow component of any general circulation model (GCM), is often overlooked in the analysis of a model's ability to simulate TCs compared to the impact of more commonly documented components (e.g., physical parameterizations). The Community Atmosphere Model version 5 is configured with multiple dynamics packages. This analysis demonstrates that the dynamical core has a significant impact on storm intensity and frequency, even in the presence of similar large-scale environments. In particular, the spectral element core produces stronger TCs and more hurricanes than the finite-volume core using very similar parameterization packages despite the latter having a slightly more favorable TC environment. Furthermore, these results suggest that more detailed investigations into the impact of the GCM dynamical core on TC climatology are needed to fully understand these uncertainties. Key Points The impact of the GCM dynamical core is often overlooked in TC assessments The CAM5 dynamical core has a significant impact on TC frequency and intensity A larger effort is needed to better understand this uncertainty