Toward the development of a feature-space representation for a complex natural category domain.

This article reports data sets aimed at the development of a detailed feature-space representation for a complex natural category domain, namely 30 common subtypes of the categories of igneous, metamorphic, and sedimentary rocks. We conducted web searches to develop a library of 12 tokens each of the 30 subtypes, for a total of 360 rock pictures. In one study, subjects provided ratings along a set of 18 hypothesized primary dimensions involving visual characteristics of the rocks. In other studies, subjects provided similarity judgments among pairs of the rock tokens. Analyses are reported to validate the regularity and information value of the dimension ratings. In addition, analyses are reported that derive psychological scaling solutions from the similarity-ratings data and that interrelate the derived dimensions of the scaling solutions with the directly rated dimensions of the rocks. The stimulus set and various forms of ratings data, as well as the psychological scaling solutions, are made available on an online website (https://osf.io/w64fv/) associated with the article. The study provides a fundamental data set that should be of value for a wide variety of research purposes, including: (1) probing the statistical and psychological structure of a complex natural category domain, (2) testing models of similarity judgment, and (3) developing a feature-space representation that can be used in combination with formal models of category learning to predict classification performance in this complex natural category domain.

Podoconiosis: enfermedad olvidada por la sociedad y la comunidad médica / Podoconiosis, a society and medical community neglected disease

La podoconiosis, o «elefantiasis endémica no filariásica», es una enfermedad geoquímica que produce un tipo de linfedema de los miembros inferiores relacionado directamente con caminar descalzo por terrenos de origen volcánico en áreas con un alto índice pluviométrico anual. Posee una distribución geográfica concreta, afecta aproximadamente a un 5% de la población de las áreas endémicas, es debilitadora y desfigurante y con frecuencia lleva a la marginación social de los que la sufren. Es una enfermedad prevenible y, una vez establecida, puede mejorar con medidas terapéuticas sencillas (AU)

Podoconiosis, mossy foot or endemic non-filarial elephantiasis, is a geochemical disease that causes lower limb lymphedema; it is directly related to walking barefoot over soils of volcanic origin, in areas with a high pluviometric annual index. It has a specific geographical distribution, affecting around 5% population in areas where it is endemic. It is debilitating and disfiguring disease, which frequently leads to social margination. Podoconiosis is totally preventable and, once a diagnosis is established, it may improve with simple therapeutic measures (AU)

Demarcation of potentially mineral-deficient areas in central and northern Namibia by means of natural classification systems.

Mineral deficiencies that lead to production losses often occur concurrently with climatic and management changes. To diagnose these deficiencies in time to prevent production losses, long-term monitoring of mineral status is advisable. Different classification systems were examined to determine whether areas of possible mineral deficiencies could be identified, so that those which were promising could then be selected for further monitoring purposes. The classification systems addressed differences in soil, vegetation and geology, and were used to define the cattle-ranching areas in the central and northern districts of Namibia. Copper (Cu), Iron (Fe), zinc (Zn), manganese (Mn) and cobalt (Co) concentrations were determined in cattle livers collected at abattoirs. Pooled faecal grab samples and milk samples were collected by farmers, and used to determine phosphorus (P) and calcium (Ca), and iodine (I) status, respectively. Areas of low P concentrations could be identified by all classification systems. The lowest P concentrations were recorded in samples from the Kalahari-sand area, whereas faecal samples collected from cattle on farms in the more arid areas, where the harder soils are mostly found, rarely showed low P concentrations. In the north of the country, low iodine levels were found in milk samples collected from cows grazing on farms in the northern Kalahari broad-leaved woodland. Areas supporting animals with marginal Cu status, could be effectively identified by the detailed soil-classification system of irrigation potential. Copper concentrations were lowest in areas of arid soils, but no indication of Co, Fe, Zn, or Mn deficiencies were found. For most minerals, the geological classification was the best single indicator of areas of lower concentrations. Significant monthly variation for all minerals could also be detected within the classification system. It is concluded that specific classification systems can be useful as indicators of areas with lower mineral concentrations or possible deficiencies.

Geografia y recursos naturales

CONTENIDO: Geografia; geografia politica; geografia humana; geografia de comunicaciones; climatologia; fisiografia; orografia; geologia; recursos hidricos; recursos energeticos; recursos no renovables; yacimientos de hidrocarburos; yacimientos minerales; recursos agricolas; ecologia; uso actual de la tierra; recursos forestales, recursos ganaderos, avicolas y piscicolas; recursos de la vida silvestre