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551.
This article considers wage?–?labour activities by agricultural households in Nicaragua. It analyses the role of: (1) comparative advantage as determined by individual and household characteristics; and (2) agricultural conditions and market imperfections, in shaping wage?–?labour supply. An econometric specification is developed which allows for random household-specific effects. Results reveal that non-agricultural wage work is largely determined by comparative advantages, whereas agricultural wage work is used to deal with a number of agricultural conditions and market imperfections. 相似文献
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Elisabeth L. Øiestad Ph.D. Ritva Karinen M.Sc. Asbjørg S. Christophersen Ph.D. Vigdis Vindenes Ph.D. Liliana Bachs Ph.D. 《Journal of forensic sciences》2014,59(1):208-210
In drug‐facilitated sexual assault (DFSA) cases, drug residues may be detected in beverage remains found in cups or glasses known to have been used by the victims. In this small naturalistic study, the possibility of beverages being contaminated, either by drug concentrated oral fluid or by oral cavity contained tablets, was investigated. Analysis of residues from cups containing soft drinks was performed by immunoassay and ultra‐performance liquid chromatography‐mass spectrometry (UPLC‐MS/MS). Beverage with both added tablets and spiked oral fluid was investigated, as well as simulation of swallowing tablets. Only the residues from added tablets were positive with immunoassay, while drugs were detectable in all cups using more sensitive UPLC‐MS/MS. In conclusion, the possibility of detecting drug residues in beverages due to a contamination, from either drug concentrated oral fluid or oral cavity contained tablets at a time of consumption, should be kept in mind when performing sensitive analysis. 相似文献