other hand, have convex costs in quality and compete in a two-stage game, determining first quality and then lending rates. The main dimensions along which strategic interactions take place are the extent of diversification, as measured by size, the ability to screen and monitor, as measured by loan loss provisions, and the capacity to withstand adverse liquidity shocks, as measured by the capi...

Hajime Kayanne et al. (1) investigate diurnal changes in CO2 partial pressure (PC02) and community metabolism on Shiraho reef (Ishigaki Island, Japan) and conclude that "reefs might serve as a sink, not a source, for atmospheric CO2" because of high net organic production relative to net calcification (Table 1). This conclusion is at odds with recent reports (2, 3, 4) and data (5) suggesting th...

Shin Takasawa et al. (1) challenge the role of inositol 1,4,5-triphosphate (IP3) as an intracellular second messenger that mobilizes Ca21 in pancreatic P cells. They found that cyclic adenosine diphosphate-ribose (cADP-ribose), but not IP3, releases Ca2+ from islet microsomes. It is difficult to reconcile their results with many studies that establish IP3 as an intracellular Ca2+mobilizing seco...

To the Editor: Lamb and Stephenson (3) argue, based on reductionist approaches in isolated and skinned muscle fibers at rest, that lactate and proton accumulation during periods of contraction may augment force production by relieving inhibition of excitation-contraction coupling processes at the sarcolemma, SR and contractile apparatus. The reductionist approaches give insight to mechanisms th...