The book provides a practical guide to the application of Critical Realism (CR), an increasingly popular philosophy of social science, in empirical research projects. Each purpose-written chapter reviews major social science research methods and contains extended illustration of how to conduct inquiry using CR.

This paper considers what realist social theory can add to existing knowledge about black and minority ethnic entrepreneurs and outlines a methodology for exploring the role of the BME entrepreneur. For this group, embodied signifiers such as skills and abilities, cultural characteristics, social norms, and value systems combine with structural antecedents, such as financial, contractual, professional, and other national and regional institutional arrangements to create impediments on the progression of BME enterprises. Understanding such complex social arrangements presents significant ontological and (...) methodological challenges. We argue that previous research has failed to capture the richness of the forms of agency BME entrepreneurs display and that, as a consequence, RST has much to offer this debate. The paper ends with a discussion of the methodological implications of analysing BME entrepreneurs in terms of their social agency. (shrink)

Interest in the role of nitric oxide (NO) in the nervous system began with the demonstration that glutamate receptor activation in cerebellar slices causes the formation of a diffusible messenger with properties similar to those of the endothelium-derived relaxing factor. It is now clear that this is due to the Ca2+/calmodulin-dependent activation of the enzyme NO synthase, which forms NO and citrulline from the amino acid L-arginine. The cerebellum has very high levels of NO synthase, and although it has low (...) levels of guanylyl cyclase, cerebellar cyclic guanosine monophosphate (cGMP) levels are an order of magnitude higher than in other brain regions. A transcellular metabolic pathway is also present in the cerebellar cortex to recycle citrulline back to arginine. The NO formed binds to and activates soluble guanylyl cyclase to elevate cGMP levels in target cells. Studies employing NADPH-diaphorase, a selective histochemical marker for NO synthase, together with immunohistochemistry, in situ hybridization and biochemical studies have indicated that NO production occurs in granule and basket cells in the cerebellar cortex, whereas cGMP formation appears to occur largely in other cells, including Purkinje cells. Given that a long-term depression of AMPA currents can be seen in isolated Purkinje cells, this anatomical localization suggests that NO cannot play an essential role in the induction of this form of synaptic plasticity. (shrink)