Reeves effect

An anomeric carbon with an axial hydroxy group usually resonates at higher field than the corresponding C-1 with an equatorial hydroxy group (rule (5)). This rule allows one to prove, experimentally, that arabinose exists in the C4 and not in the 4C, conformation, in which most sugars occur in solution [88, 726]. However, rule (5) is not valid for the mannose, rhamnose and talose anomers. This was attributed to the presence of three closely spaced dipoles (Reeves effect) present in the /J-anomeric configuration of these three sugars [683, 684] (Fig. 5.7). 

Thomas, F. I. M. and Atkinson, M. J. (1997). Ammonium uptake by coral reefs effects of water velocity and surface roughness on mass transfer, Limnol. Oceanogr., 42, 81-88. 

Hay ME (1991) Fish-seaweed interactions on coral reefs effects of herbivorous fishes and adaptations of their prey. In Sale PF (ed) The ecology of fishes on coral reefs. Academic, San Diego, CA, pp 96-119... 

Hearn, C.J., Atkinson, M.J. and Falter, J.L. (2001) A physical derivation of nutrient-uptake rates in coral reefs effects of roughness and waves. Coral Reefs, 20, 347-356. 

In addition to climate change, the increased atmospheric concentration of C02 is likely to have wide-spread ecological effects in various environments, since C02 is a physiologically active gas, in plants as well as animals. The acidic nature of C02 will also lead to changes in the chemistry of the ocean s surface, which is in equilibrium with the atmosphere. Once the shift in the oceanic chemical balance becomes significant, it will affect ecosystems. It has been shown, for example, that doubling C02 concentration in the atmosphere will reduce the rate of calcium carbonate deposition in coral reefs by 30-40% (Langdon et al., 2000). 

Langdon, C., Takahashi, T., Sweeney, C., Chipman, D., Goddard, J., Marubini, F., Aceves, H., Barnett, H., and Atkinson, M.J., Effect of calcium carbonate saturation state on the calcification rate of an experimental coral reef, Global Biogeochem. Cy., 14, 639-654,2000. 

Human activities have resulted in exposure of Antarctic fishes to petroleum-derived PAHs (McDonald et al. 1992). Fish captured near Palmer station on the Antarctic peninsula had induced EROD activities and elevated concentrations of biliary PAH metabolites of phenanthrene and naphthalene when compared to conspecifics from reference sites (McDonald et al. 1995). Artificial reefs consisting of oil and coal flyash stabilized with cement and lime in Florida waters near Vero Beach contained elevated PAH levels ranging from as high as 1.2 mg fluoranthene/kg and 0.25 mg naphthalene/kg. But there is negligible leaching because seawater is not an effective medium for removing PAHs from reef bricks or the ash (Frease and Windsor 1991). 

Most of the current commercial operations that treat PGM from sulphide-dominated deposits are located in South Africa (Morensky Reef), Stillwater mines (Montana, USA) and Lac des Hies (Ontario, Canada). From a processing point of view, most of these ore types contain hydrophobic gangue minerals, including talc, which has a negative effect on PGM recoveries. Other major factor that affects flotation recovery of PGM is the presence of a variety of sulphide minerals, including pyrrhotite, pentlandite, chalcopyrite, violarite and pyrite, where... 

Patterson, M. R., Sebens, K. P. and Olson, R. R. (1991). In situ measurements of flow effects on primary production and dark respiration in reef corals, Limnol. Oceanogr., 36, 936-948. 

Atkinson, M. J. and Bilger, R. W. (1992). Effects of water velocity on phosphate-uptake in coral reef-flat communities, Limnol. Oceanogr., 37, 273-279. 

Carpenter RC (1986) Partitioning herbivory and its effects on coral reef algal communities. Ecol Monogr 56 345-346... 

Hay ME, Duffy JE, Fenical W, Gustafson K (1988a) Chemical defense in the seaweed Dictyopteris delicatula. differential effects against reef fishes and amphipods. Mar Ecol Prog Ser 48 185-192... 

Paul VJ, Hay ME, Duffy JE, Fenical W, Gustafson K (1987) Chemical defense in the seaweed Ochtodes secundiramea (Montague) Howe (Rhodophyta) effects of its monoterpenoid components upon diverse coral-reef herbivores. J Exp Mar Biol Ecol 114 249-260 Paul VJ, Cruz-Rivera E, Thacker RW (2001) Chemical mediation of macroalgal-herbivore interactions ecological and evolutionary perspectives. In McClintock JB, Baker BJ (eds) Marine chemical ecology. CRC, pp 227-265... 

The point is also made [134] that the very high surface areas and the richly interconnected three-dimensional networks of these micron-sized spaces, coupled with periods of desiccation, could together have produced microenvironments rich in cat-alytically produced complex chemicals and possibly membrane-endosed vesides of bacterial size. These processes would provide the proximate concatenation of lipid vesicular precursors with the complex chemicals that would ultimately produce the autocatalytic and self-replicating chiral systems. A 2.5 km2 granite reef is estimated to contain possibly 1018 catalytic microreactors, open by diffusion to the dynamic reservoir of organic molecules. .. but protected from the dispersive effects of flow and convection [134] as well as protected from the high flux of ultraviolet radiation impinging on the early Earth. [123,137]... 

Inhibition of cytochromes of electron transport system can be caused by cyanogenic glycosides, such as amygdalin (Fig. 11.14) in bitter almonds, Prunus amygdalus, linamarin and lotaustralin in clover and birdsfoot trefoil, or dhurrin (Fig. 11.14) in Sorghum vulgare. The potent effect of cyanide on cell respiration has given rise to a recent serious conservation problem. In Southeast Asia, divers stun fish on coral reefs with a blast of cyanide to collect them for the aquarium trade. In the process, many fish are killed and the corals bleached, because their symbionts die (e.g. Payne, 2001). 

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