Calculation of precision in isotope dilution experiments.
Abstract Equations are derived for the composite error of isotope dilution measurements in three types of experiment viz. simple dilution, saturation analysis (sub-stoichiometric dilution) and adsorbed ion measurement; the latter two yielding equations of the same form. Errors for each type are derived in terms of radiometric errors, chemical errors and a factor related to the extent of isotope dilution. In general, dilution is the most critical factor which controls error; chemical errors are usually less important than radiometric errors. A nomogram for calculating dilution errors is given.
The influence of the statistical error in radioactivity counting on the precision of isotope dilution analysis, II
Three types of direct isotope dilution analysis (IDA) are mathematically treated: substoichiometric dilution analysis, the determination of sorbent capacity, and direct IDA with a constant amount of substance lost in the separation step. Tables and graphs are given for an easy determination of the amount of radioisotopeW0 to be added and for the estimated error involved.
Morpho-biometric Relationship, Relative Condition Factor and Meat Yield of Distant Scallop Bractechlamys vexillum (Reeve, 1853) in Asid Gulf, Philippines
Understanding the relationships of morphometric and biometric characters of a species allows the prediction of one trait from the other and generate a measure of relative condition. These relationships were studied for the Distant scallop Bratechlamys vexillum (Reeve, 1853) in Asid Gulf. Representative samples collected during the dry season (May 2018, n = 99) and wet season (September 2018, n = 100) were used to analyse these relationships through models of simple linear and power regression analyses, revealing allometric growth patterns. For both periods, it was revealed that shell width (SW) is a slightly better predictor than the height (SH) for total weight (TW) (R2 = 0.90 and 0.92) and the adductor muscle weight (AW) (R2 = 0.78 and 0.80). The strong functional relationship was also observed between TW and AW (R2 = 0.80 and 0.81). The relative condition factors (Kn) were high in both seasons. High meat yields were also observed in May (12.77 %) and September (14.26 %). The significant difference in meat yields (P < 0.05) can be a result of the seasonal difference manifested by the dynamics of energy partitioning during gametogenesis and spawning. These biological metrics are vital inputs in analysing mariculture prospects for the resource and a contribution to the scarce information on the biology of the species.