A conceptual framework is presented to portray how Fe, S and other elements (Ca, Si, K) are geologically and pedologically cycled between minerals that are formed and are stable in land-based aerobic environments and those that are formed and are stable in anaerobic sea-based environments.
Her mother cycled between drinking and sobriety.
The "classic" Rho GTPases cycle between two forms, GDP- or GTP-bound.
Iron will cycle between the two forms during LDL oxidation, and it was therefore of interest to examine the oxidation of LDL with ferrous and ferric iron.
Foremost among the elements discussed are Fe and S, which cycle between Fe sulfides, formed by sulfidization in the anaerobic sea-based environments of tidal marsh and subaqueous soils and sediments, and Fe oxides and jarosite, formed by sulfuricization in upland soils upon the exposure of the sulfide-mineral bearing sediments to oxidizing conditions.
Finally, an unidentified protein or group of proteins migrating at 100 to 116 kDa increase in tyrosine phosphorylation throughout maturation, are dephosphorylated or degraded within 10 min of fertilization, and appear to cycle between low-molecular-weight forms and high-molecular-weight forms during early embryogenesis.
ROPs cycle between the GTP-binding form and the GDP-binding form, thus regulating a variety of cellular responses [ 24].
In the environment, Mn cycles between the soluble reduced form Mn II) and the insoluble oxidized forms Mn III and IV) that can adsorb other trace metals from the environment and react as potent oxidizing agents.
The active site of thioredoxin consists of two neighboring cysteines, as part of a highly conserved CXXC motif, that can cycle between an active dithiol form (reduced) and an oxidized disulfide form.
Subsequent letters were presented immediately following each button press, forming a regular sequence that cycled through the alphabet, skipping two letters between each stimulus and the next.
These GTPases cycle between an active GTP-bound form and inactive GDP-bound form, and regulate a variety of cytoskeletal molecules [8], [9].
