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The jellyfish species from Foster City, San Francisco Bay, CA, probably originates from Japan. The Aurelia species medusae is morphologically different from those in Monterey Bay just 200 kms away but similar to the aquarium-cultured Aurelia species from Japan. Allozyme electrophoresis reveals differences at 12 of the 14 polymorphic loci, thereby indicating that Aurelia species from Foster City and Tokyo Bay are part of the same species most likely transported in ships' ballast water. Aurelia species from Monterey Bay and Vancouver Island, however, belong to another species.

This paper compares an extended conventional filter technique for automated detection and analysis of rapid eye movements (REM) in neonates, using amplitude, synchrony, velocity, and coherence threshold criteria, with a matched filtering technique using the morphology of the REM waveform. Analyses of both simulated and real data were carried out. Automated REM tabulations are compared with visual scoring by a trained observer. Both preterm and fullterm neonates were used to test these methods. Both the advantages and disadvantages of these two techniques are discussed as compared with conventional methods which use only amplitude and synchrony threshold criteria. The major advantage of the extended conventional over the conventional method, as well as the matched filtering over the extended conventional technique, is the increased REM detection rate for ten minute intervals of artifact-free sleep. More accurate methods of automated REM detection that can be applied over extended monitoring periods are still needed.

The objective of this study was to use high-fidelity animal data and numerical simulations to gain more insight into the reliability of the estimated relaxation constant derived from left ventricular pressure decays, assuming a monoexponential model with either a fixed zero or free moving pressure asymptote. Comparison of the experimental data with the results of the simulations demonstrated a trade off between the fixed zero and the free moving asymptote approach. The latter method more closely fits the pressure curves and has the advantage of producing an extra coefficient with potential diagnostic information. On the other hand, this method suffers from larger standard errors on the estimated coefficients. The method with fixed zero asymptote produces values of the time constant of isovolumetric relaxation ([Tau]) within a narrow confidence interval. However, if the pressure curve is actually decaying to a nonzero pressure asymptote, this method results in an inferior fit of the pressure curve and a biased estimation of [Tau]. hemodynamics; left ventricular relaxation constant; simulation

The first step of any molecular study should be to confirm the species of interest, ruling out contamination and/or DNA collection or extraction error. Despite a recent wealth of genetic and sequence data on humans and great apes, few molecular techniques are available for easily and efficiently distinguishing between hominoid species. We have developed a single-PCR assay for identifying hominoid species using lineage-specific LINE-1 (Long Interspersed Element) insertions. LINE-1 (L1) elements belong to a family of retrotransposons that have influenced the evolution of eukaryotic species for over 600 million years. L1s that inserted into the genome of a species after its divergence from its Last Common Ancestor ate unique to that species. Thus, the presence of a species-specific L1 insertion in a DNA sample positively identifies the species origin of the sample. There are 500,000 L1s in the human genome but virtually nothing is known about the L1s in other primates. We developed a technique to construct 'LOAF' libraries that contain recent L1 insertions from primate genomes. From LOAF libraries, we identified insertions that are unique to each of the great ape species. For each species-specific insertion, we developed a PCR assay capable of detecting both the presence ('occupied allele') and the absence ('empty allele') of the L1 insertion. These assays are capable of rapidly and unambiguously identifying the species of origin of a DNA sample. We are currently extending this approach to develop assays for distinguishing between Old and New World monkeys, and prosimians.