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Based on structural information, we have analyzed the mechanism of mature HIV-1 core assembly and the contributions of structural elements to the assembly process. Through the use of several in vitro assembly assay systems, we have examined details of how capsid (CA) protein helix 1, ß-hairpin and cyclophilin loop elements impact assembly-dependent protein interactions, and we present evidence for a contribution of CA helix 6 to the mature assembly-competent conformation of CA. Additional experiments with mixtures of proteins in assembly reactions provide novel analyses of the mature core assembly mechanism. Our results support a model in which initial assembly products serve as scaffolds for further assembly by converting incoming subunits to assembly proficient conformations, while mutant subunits increase the probability of assembly termination events., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Dinosaur extinction in Montana, Alberta, and Wyoming was a gradual process that began 7 million years before the end of the Cretaceous and accelerated rapidly in the final 0.3 million years of the Cretaceous, during the interval of apparent competition from rapidly evolving immigrating ungulates. This interval involves rapid reduction in both diversity and population density of dinosaurs. The last dinosaurs known are from a channel that contains teeth of Mantuan mammals, seven species of dinosaurs, and Paleocene pollen. The top of this channel is 1.3 meters above the likely position of the iridium anomaly, the Cretaceous/Tertiary boundary.

The advantages and disadvantages of different methods of creating an age-sex register are described. The cost of setting up such a register in a NHS practice with 10,000 patients is shown, and it is suggested that financial advantages may cover the costs involved.

A portable battery-powered device was used to measure temperature in the external aural canal by a thermistor while keeping the temperature of the outer ear, monitored by a second thermistor at the same level by servo-controlled heating. Aural canal temperature then always stabilized within 0.35 degrees C of esophageal in moving air at between 18 and 45 degrees C. It often did so in colder air, but stabilization was slow even after brief exposure to the cold air. Aural temperature then paralleled esophageal within 0.35 degrees C during rapid changes in deep body temperature while rectal temperature was seriously depressed in cold air. These conclusions were based on 30 experiments on 11 male and 7 female subjects.

Sublingual and oesophageal temperatures were compared at various air temperatures in 16 subjects. In warm air (25-44 degrees C) sublingual temperatures stabilized within plus or minus 0-45 degrees C of oesophageal temperatures, but in air at room temperature (18-24 degrees C) they were sometimes as much as 1-1 degrees C below and in cold air (5-10 degrees C) as much as 4-4 degrees C below oesophageal readings. The sublingual-oesophageal temperature difference in cold air was greatly reduced by keeping the face warm, but it was not reduced in two patients breathing through tracheostomies and thereby eliminating cold air flow from the nose and pharynx. Parotid saliva temperature was low and saliva flow high during exposure, and cold saliva seemed to be mainly responsible for the erratic depression of sublingual temperature in the cold. These results indicate hazards in the casual use of sublingual temperatures, and indicate that external heat may have to be supplied to enable them to give reliable clinical assessments of body temperature.

The known range of the Primates is extended down from the middle Paleocene to the early Paleocene and late Cretaceous by a new genus and two new species from Montana, Purgatorius unio and P. ceratops. These species approach condylarths and leptictid and erinaceoid insectivores in structure. Purgatorius is referred to a new subfamily, Purgatoriinae, of the Paromomyidae, but is probably not the stem primate. The fauna of Purgatory Hill indicates a late early Paleocene age.

A series of Cretaceous mammal faunas, beginning with standard late Cretaceous faunas and continuing with three of Paleocene aspect, are summarized. Four families (Eucosmodontidae, Taeniolabididae, Leptictidae, Arctocyonidae) and one order (Condylarthra) of Tertiary mammals are extended into the Cretaceous. New genera Cimexomys, Stygimys, Procerberus, and Protungulatum are described, as is a small species of Catopsalis. The skeleton of a multituberculate is restored and multituberculate classification is revised.