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1.
Environ Sci Pollut Res Int ; 20(10): 6917-33, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23340898

RESUMEN

In densely populated countries like China, clean water is one of the most challenging issues of prospective politics and environmental planning. Water pollution and eutrophication by excessive input of nitrogen and phosphorous from nonpoint sources is mostly linked to soil erosion from agricultural land. In order to prevent such water pollution by diffuse matter fluxes, knowledge about the extent of soil loss and the spatial distribution of hot spots of soil erosion is essential. In remote areas such as the mountainous regions of the upper and middle reaches of the Yangtze River, rainfall data are scarce. Since rainfall erosivity is one of the key factors in soil erosion modeling, e.g., expressed as R factor in the Revised Universal Soil Loss Equation model, a methodology is needed to spatially determine rainfall erosivity. Our study aims at the approximation and spatial regionalization of rainfall erosivity from sparse data in the large (3,200 km(2)) and strongly mountainous catchment of the Xiangxi River, a first order tributary to the Yangtze River close to the Three Gorges Dam. As data on rainfall were only obtainable in daily records for one climate station in the central part of the catchment and five stations in its surrounding area, we approximated rainfall erosivity as R factors using regression analysis combined with elevation bands derived from a digital elevation model. The mean annual R factor (R a) amounts for approximately 5,222 MJ mm ha(-1) h(-1) a(-1). With increasing altitudes, R a rises up to maximum 7,547 MJ mm ha(-1) h(-1) a(-1) at an altitude of 3,078 m a.s.l. At the outlet of the Xiangxi catchment erosivity is at minimum with approximate R a=1,986 MJ mm ha(-1) h(-1) a(-1). The comparison of our results with R factors from high-resolution measurements at comparable study sites close to the Xiangxi catchment shows good consistance and allows us to calculate grid-based R a as input for a spatially high-resolution and area-specific assessment of soil erosion risk.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Ríos/química , Contaminantes del Agua/análisis , Contaminación del Agua/estadística & datos numéricos , Agricultura , Altitud , China , Clima , Fenómenos Geológicos , Nitrógeno/análisis , Fósforo/análisis , Lluvia , Suelo/química , Análisis Espacial , Contaminación del Agua/análisis
2.
J Morphol ; 272(3): 259-79, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21312226

RESUMEN

The anatomy of five bathysciadiid limpets, the type species Bathysciadium costulatum (Locard, 1898), Bathysciadium sp. B (off New Zealand), Bathypelta pacifica (Dall, 1908), Bathypelta sp. A (off New Zealand), and Bathyaltum wareni n.g., n.sp. (deep East Atlantic Ocean Basins), which all feed on decaying cephalopod beaks, has been investigated by means of semithin serial sectioning and interactive, computer-aided 3D reconstructions. Bathyaltum wareni is described as a species new to science based on additional SEM photos of shell and radula. Differences between species are found in conditions of shell, protoconch, mantle papilla, copulatory organ, receptaculum openings, oral lappets, and rectal histology. The Bathysciadiidae share several synapomorphies with the Cocculinidae (s. str.), namely the pseudoplicatid gill, a single, left kidney, the hermaphroditic gonad with the single, glandular gonoduct, and the statocysts with single statoliths. Therefore, these families are united in a clade Cocculinoidea, which is considered to be highly modified offshoot of early gastropods independent of the likewise "cocculiniform" Lepetelloidea, which should be classified among the Vetigastropoda.


Asunto(s)
Gastrópodos/anatomía & histología , Animales , Océano Atlántico , Cefalópodos , Gastrópodos/ultraestructura , Nueva Zelanda
3.
Pflege Z ; 60(4): 206-9, 2007 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-17494428

RESUMEN

Nurses' attitudes influence decisions on physical restraints. A literature analysis was conducted on nurses', patients', and their families' attitudes towards physical restraint use in the elderly. While nurses' attitudes are characterized by ambivalence, patients and their relatives express mainly negative feelings towards the use of physical restraints. Knowledge about nurses', patients', and their relatives' attitudes is indispensable for the development of alternative interventions. Patients' dignity as well as their right to freedom and movement must be respected and protected.


Asunto(s)
Actitud del Personal de Salud , Cuidadores/psicología , Enfermería Geriátrica , Restricción Física/psicología , Accidentes por Caídas/prevención & control , Anciano , Anciano de 80 o más Años , Alemania , Humanos , Relaciones Profesional-Familia
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