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Using ethnographic data collected in a second grade classroom over the course of a school year, this paper describes the ways in which one school's discourse of liberalism is deleteriously deployed. We view the school's discipline creed as emblematic of the school's liberal curriculum, and interrogate the effects on four African American boys in the classroom when the school enacts this creed. Despite the agency that these boys obviously had, they were unable to control the ways in which they were placed at a structural disadvantage and manipulated by a system far more powerful than they were. The results were that these four boys suffered. Not only did the intended liberal curriculum fail to be translated fully into the enacted curriculum, the liberal underpinnings of this curriculum precluded teachers and students from taking any critical stance. 相似文献
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Richard W. Joy IV Kamlesh R. Patel Trevor A. Thorpe 《Plant Cell, Tissue and Organ Culture》1988,13(3):219-228
The effect of ascorbic acid on growth and shoot formation in callus cultures of tobacco (Nicotiana tabacum L.) was investigated, using young (4–12 subcultures) and old (more than 30 subcultures) tissue. It was found that ascorbate, at levels of 4–8×10-4M, enhanced shoot formation in both young and old callus. Treatment with ascorbate also speeded up the shoot-forming process. In addition, ascorbate completely reversed the inhibition of shoot formation by gibberellic acid in young callus, but was less effective in old callus. 相似文献
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TRANSFORMATION of allogenic lymphocytes in mixed cultures depends chiefly on an incompatibility between the lymphocyte donors at the major histocompatibility locus in man (HL-A), mouse (H-2) and rat (H-l)1. Although the mouse H-2 locus can be divided into several regions each of which controls one or more antigenic specificities2 and two or more subloci control HL-A antigens in man3, it is not known whether all parts of the major histocompatibility locus are equally important in eliciting transformation in mixed lymphocyte cultures. We now show that capacity to elicit lymphocyte transformation is different for different parts of the mouse H-2 locus. 相似文献
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Pathways and rates of metabolism of three 14C1-compounds (methanol, formaldehyde, and formic acid) were investigated by means of the heterogeneous population of activated sludge microorganisms. For the above microbial population formaldehyde was the primary or preferential substrate. During an hour aeration it was processed by activated sludge 6 times faster than by sodium formiate and 2 times faster than by methanol. The basic pathways of its transformation were oxidation via formiate to CO2 with its partial reutilization and direct incorporation into the sludge biomass via the primary formation of serine. An addition of methanol increased the incorporation of 14C-formadehyde into biomass and decreased the formation of free 14CO2. The main mechanism of the transformation of 14C-formiate in activated sludge was its oxidation to CO2. An addition of methanol and formaldehyde induced no essential changes in the rate or pattern of their metabolism. 相似文献
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Richard W. Joy IV 《In vitro cellular & developmental biology. Plant》1995,31(3):176-177