The ability of human and rat D2(short) and D2(long) dopamine receptors to activate microtubule‐associated protein (MAP) kinase (Erk1/2) and p70 S6 kinase has been investigated in recombinant cells expressing these receptors. In cells expressing the D2(short) receptor, dopamine activated both enzymes in a transient manner but with very different time courses, with activation of Erk being much quicker. Activation of both enzymes by dopamine was dose‐dependent and could be prevented by a range of selective dopamine antagonists. Excellent correlations were observed between the potencies of the antagonists for blocking enzyme activation and their affinities for the D2 dopamine receptor. Activation of Erk and of p70 S6 kinase via the D2 dopamine receptors was prevented by pretreatment of the cells with pertussis toxin, indicating the involvement of G proteins of the Gi or Go family. Inhibitors of phosphatidylinositol 3‐kinase (PI 3‐kinase) were found to block substantially, but not completely, activation of p70 S6 kinase by dopamine, suggesting the involvement of PI 3‐kinase‐dependent and ‐independent signalling pathways in its control by dopamine. p70 S6 kinase activation was completely blocked by rapamycin. In the case of Erk, activation was partially blocked by wortmannin or LY294002, indicating a possible link with PI 3‐kinase.

Ocean warming is transforming the world’s coral reefs, which are governed by the growth of marine calcifiers, most notably branching corals. Critical to skeletal growth is the corals’ regulation of their internal chemistry to promote calcification. Here we investigate the effects of temperature and light on the calcifying fluid chemistry (using boron isotope systematics), calcification rates, metabolic rates and photo-physiology of Acropora nasuta during two mesocosm experiments simulating seasonal and static temperature and light regimes. Under the seasonal regime, coral calcification rates, calcifying fluid carbonate chemistry, photo-physiology and metabolic productivity responded to both changes in temperature and light. However, under static conditions the artificially prolonged exposure to summer temperatures resulted in heat stress and a heightened sensitivity to light. Our results indicate that temperature and light effects on coral physiology and calcification mechanisms are interactive and context-specific, making it essential to conduct realistic multi-variate dynamic experiments in order to predict how coral calcification will respond to ocean warming.

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The book argues that the invention and popularization of the shopping cart from the 1940s onward provided the final link in the chain for the new system of industrialized food flow. First in the United States and then around the world, these carts enabled supermarkets to move their goods even faster off their shelves—in a sense, completing the revolution in mechanized farming, electric refrigeration, and road distribution that had occurred during the 1930s. Yet the cart, a basic machine among modernity’s new systems, also recast the work of food shopping in ways that attracted ambivalence and unease. In urging customers to buy all their groceries at once, it radically accelerated the consumerist experience of self-service, creating a new mode of accelerated shopping on impulse that often felt, ironically, far from “convenient.” Above all, as a host of U.S. cultural responses have suggested, the sheer uniformity of the shopping cart has unsettled the individualistic rhetoric of the supermarket industry. Increasingly omnipresent in online shopping, its basic form, defined as a void waiting to be filled, uncomfortably reveals the parallels that exist between human and nonhuman participants in the modern circuit of food flow.