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321.
Helen Ruth Aspaas 《The Professional geographer》1998,50(2):192-204
The dynamics of intra-household economics among sedentary farmers in rural Kenya suggest that women, whether or not they have a male household head, are responsible for providing basic resources to insure the daily survival of household members. Many rural Kenyan women operate small businesses in rural market centers in order to meet these obligations, and many of these women are also heads of their households. This paper examines women's resource bases for establishing and maintaining small-scale businesses. Compared to women who are associated with male-headed households, women who head households have fewer resources for establishing businesses which in turn generate lower earnings. At the same time, these women are almost completely dependent on their businesses for meeting the household's needs. 相似文献
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Effects of the North American polychaete Marenzelleria cf. viridis on a simple shallow-water benthic community of the northern Baltic Sea were studied in a field experiment combining natural densities of dominating macrofaunal species. The presence of M. cf. viridis increased benthic production (chlorophyll a) and reduced the survival of the native polychaete Nereis diversicolor. Adult Macoma balthica caused a significant mortality on M. cf. viridis whereas adult Cerastoderma glaucum had no effect on M. cf. viridis. We suggest that the competitive interactions between M. cf. viridis and M. balthica are a possible key factor determining the distribution pattern of M. cf. viridis in the Baltic Sea. 相似文献
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Perelet Alexei O. Ward Helen C. Stoll Rob Mahaffee Walter F. Pardyjak Eric R. 《Boundary-Layer Meteorology》2022,184(3):479-504
Boundary-Layer Meteorology - Scintillometry is a non-invasive measurement technique for acquiring spatially-averaged surface heat and moisture fluxes in areas where setting up arrays of instruments... 相似文献
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The Cane Run Bed is a prominent unit of micrograined limestone and shale of distal storm origin in the lower part of the Late Ordovician (late Chatfieldian; late Caradoc) Lexington Limestone (Trenton) in central Kentucky, USA. The unit's prominence relates to presence of up to three horizons of penecontemporaneous, soft-sediment deformation that form a distinctive event bed; equivalent horizons of different lithology are also deformed. Concurrence of four lines of evidence, including deformation consistent with a seismogenic origin, widespread distribution in temporally and stratigraphically constrained horizons, a pattern of increasing frequency or deformation intensity toward likely epicentral areas, and the ability to exclude other likely causes, points strongly to a seismogenic origin for each horizon. This interpretation is bolstered by the facts that the deformation contains random fold axes, crosses facies boundaries, is associated with a periodically reactivated basement structural lineament, and crosscuts undeformed beds from both above and below. Moreover, mapping the distribution of deformation intensity allows for the interpretation of possible epicentral areas. The association of Cane Run deformation with other sedimentologic-stratigraphic anomalies related to reactivated basement faults, as well as their coincidence with the inception of a Taconian tectophase, suggest that Cane Run seismites are one of several responses to the distal transmission of far-field forces from the coeval Taconian orogeny into the foreland, largely via zones of basement structural weakness. Units like the Cane Run Bed and its equivalents, whose seismogenic origins can be confidently demonstrated, suggest that seismicity must have had a substantial influence at times on epicontinental sedimentation, even in seas far removed from orogenic sources of stress. 相似文献
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