Book Reviews

Review of Prehistory, by Derek Roe; Aspects of Prehistory, by Grahame Clark; World Prehistory, by Grahame Clark; Introductory Readings in Archaeology, by Brian M. Fagan, ed.; The Origins of Civilization, by Carroll L. Riley; The Archaeology of Early Man, by J. M. Coles and E. S. Higgs; Shipwrecks and Archaeology, by Peter Throckmorton; A History of Dyed Textiles, by Stuart Robinson; Food in Antiquity, by Don and Patricia Brothwell; World Archaeology, Vol. 1, nos. 1, 2, 3, by Roy Hodson and Colin Platt, eds.; The Structure and Growth of Australia's Aboriginal Population, by F. Lancaster Jones; Attitudes and Social Conditions, by Ronald Taft, John L. M. Dawson, and Pamela Beasley; Aboriginal Settlements, by J. P. M. Long; The Destruction of Aboriginal Society, by C. D. Rowley; Aboriginal Advancement to Integration, by H. P. Schapper

Clarifying plasma melatonin profiles in domestic pigs: a critical and comparative evaluation of two radioimmunoassay systems

The results of a direct radioimmunoassay (RIA) for porcine plasma melatonin, suggesting a relationship among plasma melatonin, feed intake and photoperiod, were investigated by comparison with the results of an extracted RIA. These findings were further examined by analysis of a small number of samples using gas chromatography-mass spectrometry (GCMS). The results identified inadequacies in the specificity of the direct RIA and failed to provide evidence for an effect of feed intake on melatonin secretion. Instead, it appeared that feed restriction exacerbated nonspecificity in the direct RIA. The cause of nonspecificity, and its effect on analysis of daily plasma melatonin profiles, were examined. The plasma component(s) responsible for nonspecificity was (were) not identified. However, the results suggest that characteristics of the antiserum used in the direct RIA are involved in the mechanism by which nonspecificity is induced. Results obtained using the extracted assay revealed that plasma melatonin concentrations in prepubertal gilts and pregnant sows exhibit a diurnal pattern, in which concentrations are low during daylight and modestly increased during darkness. Using the direct RIA, the same profiles exhibited highly variable melatonin concentrations showing little association with the light-dark cycle. Thus, assay specificity was identified as a factor contributing to inconsistencies in the literature describing plasma melatonin in the domestic pig and the importance of rigorous validation of RIAs was demonstrated. Furthermore, the results indicate that plasma melatonin concentrations in domestic pigs, as in other mammalian species, are entrained by the light-dark cycle

Spins, parity, excitation energies, and octupole structure of an excited superdeformed band in 194^{194}Hg and implications for identical bands

An excited superdeformed band in 194Hg, observed to decay directly to both normal-deformed and superdeformed yrast states, is proposed to be a Kπ = 2− octupole vibrational band, based on its excitation energies, spins, and likely parity. The transition energies are identical to those of the yrast superdeformed band in 192Hg, but originate from levels with different spins and parities. The evolution of transition energies with spin suggests that cancellations between pairing and particle alignment are partly responsible for the identical transition energies