Term Litters

Deciphering the code. The language of computational chemistry is littered with acronyms, what do these abbreviations stand for in terms of underlying assumptions and approximations ... 

Particulate organic matter LF — 2-18% of organic C, 1-16% of total N SSF - 20 45% of organic C and 13-40% of total N Partially decomposed plant litter isolated by density fractionation (LF) or sieving (SSF). Substrate and centre for soil microbial activity, short-term reservoir of nutrients, food source for earthworms and other soil fauna and focci for formation of water stable aggregates. 

The persistence of polymers in the environments is useful for long term durability of structures such as buildings, vehicles, docks, boats and navigation aids. Unfortunately, when the polymers are unintentional byproducts of recreational or commercial activities, collateral wildlife loss may result from entanglement in packaging materials, lost nets, lines and ropes. These wildlife losses due to litter have received significant public visibility. The critical degradation to address this... 

Peat was far superior in terms of absoption capacity to the other litters. Litter should retain its absorption capacity even when under pressure, for example in a hydraulic manure press. 

The concentrations of phenolic and polyphenollc allelochemlcals that inhibited the various reactions of Isolated chloroplasts and mitochondria have been reported to occur, either singularly or in combination, in organic litter ( ). The studies conducted herein were short-term, on the order of several minutes, in which immediate responses were measured. Preincubation of the allelochemlcals with the test systems could be expected to lower the concentrations required to produce inhibition. 

The prenatal developmental toxicity study design includes sacrifice of the rodent or rabbit dam one day prior to expected delivery, in order to ensure that malformed fetuses are not lost to maternal cannibalism. .. Nevertheless, even the prenatal developmental toxicity study does not allow the researcher to distinguish the source or cause of prenatal mortality. Intrauterine deaths may be the result of malformations that are incompatible with continuing viability... The contribution of malformed fetuses to overall effect on litter viability can be appropriately analysed by combining the litter incidence of conceptuses that are malformed, resorbed (early and late), and dead (full term but nonviable at caesarean section) and performing appropriate statistical analyses of group values (13). 

In terms of toxicology and long-term side effects, data in humans are not available and data from animal studies are informative but not definitive. Prenatal exposure of rats to fluoxetine has yielded mixed findings, as reviewed elsewhere (Emslie et ah, 1999). Vorhees et ah (1994) reported reduced litter sizes at high doses, but no significant effects on locomotor activity or per-... 

Excipients are thus one of the three components that in combination produce the medicine that the patient will take. In therapeutic terms, the API is of primary importance because without it there is no treatment and no product. However, in terms of the development and manufacture of the product, all three components are equally important, and we neglect any one of them at our peril. The annals of formulation development in most companies, both large and small, are probably littered with examples where some aspect of one of these three components has been neglected in some way, with unfortunate consequences for the project. The interactions between excipients and the other two components (the API and the manufacturing process), and/or between two or more excipients, are fundamental to the transformation of an API into a medicinal product. 

Harmon, M. E., Nadelhoffer, K. J., and Blair, J. M. (1999). Measuring decomposition, nutrient turnover, and stores in plant litter. In Standard Soil Methods for Long-Term Ecological Research. Robertson, G. R, Bledsoe, C. S., Coleman, D. C., and Sollins, R, eds., Oxford University Press, New York, pp. 202-240. 

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