New merycodonts from the upper Miocene of Nevada

In an Upper Miocene assemblage of mammals recently brought together, occur remains of numerous individuals referable to the genus Merycodus. The collection represents several seasons of palaeontological field work by parties from the California Institute of Technology in the vicinity of Tonopah, Nevada. The specimens of Merycodus exhibit characters that are not common to those of species described from other localities in the Great Basin Province or from West Coast Miocene and Pliocene deposits. In some respects, the new Nevada forms combine characters seen in M. furcatus and M. necatus, found in deposits of similar age. Differences of structure among the materials represented indicate the presence of two distinct species of Tonopah merycodonts. In a study of the new types, an analysis of the morphologic characters of the genus emphasizes the essentially constant premolar tooth pattern for Merycodus. As may be expected, greater diversity occurs among merycodont horn-core structures, particularly as to shape and size. However, the supraorbital position of the horn-cores is apparently constant within specific groups. In the present comparative studies, I am particularly indebted to Dr. Charles L. Camp and to Mr. R. A. Stirton of the Museum of Palaeontology, University of California, for the loan of Merycodus material. Mr. John L. Ridgway has prepared the drawings and has arranged the plates

A lifting surface computer code with jet-in-crossflow interference effects. Volume 1: Theoretical description

A method is proposed to combine a numerical description of a jet in a crossflow with a lifting surface panel code to calculate the jet/aerodynamic-surface interference effects on a V/STOL aircraft. An iterative technique is suggested that starts with a model for the properties of a jet/flat plate configuration and modifies these properties based on the flow field calculated for the configuration of interest. The method would estimate the pressures, forces, and moments on an aircraft out of ground effect. A first-order approximation to the method suggested is developed and applied to two simple configurations. The first-order approximation is a noniterative precedure which does not allow for interactions between multiple jets in a crossflow and also does not account for the influence of lifting surfaces on the jet properties. The jet/flat plate model utilized in the examples presented is restricted to a uniform round jet injected perpendicularly into a uniform crossflow for a range of jet-to-crossflow velocity ratios from three to ten

Distribution and description of skull remains of the Pliocene antelope Sphenophalos from the northern Great Basin Province

With the progress of paleontological explorations in the later Tertiary deposits of the northern Great Basin Province by the California Institute of Technology in cooperation with Carnegie Institution of Washington additional materials of the antilocaprid genus Sphenophalos have been found. Of particular interest is the discovery of remains of this mammal in new Pliocene faunas of eastern Oregon, thus extending the known range of Sphenophalos. While no complete skull is available, the specimens collected include a number of horn-cores whose structure is of considerable significance in a determination of the genetic relationships of the genus

The Occurrence and Phylogenetic Status of Merycodus from the Mohave Desert Tertiary

The collections of the University of California Museum of Paleontology contain a fairly representative assemblage of Merycodus skeletal elements from the Great Basin province. During the collecting seasons of 1925 and 1926, Miss Annie M. Alexander and Miss Louise Kellogg discovered in the Barstow and the Ricardo deposits of the Mohave Desert unusually complete series of limb bones associated with Merycodus skulls. The associated skeletal remains, with the numerous dissociated limb bones, cranial bones, and teeth from these and other localities, afford opportunity to observe the constancy of osteological characters within this group as well as a sound basis for morphological comparison with other genera of the Antilocapridae and Cervidae

Capromeryx minor Taylor from the McKittrick Pleistocene, California

The occurrence of a Pleistocene vertebrate fauna in an asphalt deposit near McKittrick, California, has been reported by J. C. Merriam and C. Stock. Since the publication of the provisional list of mammals from this locality, several types new to the assemblage have been discovered in the deposit. Among these should be recorded the small antilocaprid, Capromeryx minor. This species occurs here in association with the prong-horn antelope Antilocapra. Three species of the genus Capromeryx are now known from the Pleistocene of North America. The type, C. furcifer, was described by Matthew from Hay Springs, Nebraska. C. minor Taylor occurs at Rancho La Brea, and C. mexicana Furlong is recorded from Tequixquiac, Mexico. The occurrence of C. minor at McKittrick extends the range of this species during the Pleistocene from the Los Angeles basin to the Great Valley of California. Members of the family Antilocapridre are apparently sparsely represented in the McKittrick fauna, as only one individual of Capromeryx has been found, while several individuals of Antilocapra are known to occur

ACUTE EFFECTS OF WHOLE-BODY VIBRATION ON ELASTIC CHARGE TIME IN TRAINED MALE ATHLETES

Whole-body vibration (WBV) has been shown to increase jump height, power and strength but the mechanisms behind these changes are not fully understood. The aim of this study was to investigate the influence of WBV on elastic charge time, a surrogate measure of tendon and aponeurosis stiffness. 7 trained males were exposed to 10 vibrations at 30 Hz ± 4 mm with 60 seconds rest between each exposure. Pre and post-tests were conducted immediately, 5, 10, 15, 20, 30 and 40 minutes following vibration exposure. A significant increase in elastic charge times of both vibrated (p=0.004) and control (p=0.024) limbs suggest whole-body vibration decreases tendon and aponeurosis stiffness, possibly due to a warm-up effect of the lower limbs. Further study of the muscle stiffness response to vibration will improve understanding of the mechanisms behind performance improvements following vibration exposure

Trading off Time, Carbon, Active Travel, and Health: What do People Really Think about Traffic-reduction Measures?

An online survey polled a socio-demographically representative sample of approximately 2,000 UK residents concerning their attitudes to traffic restrictions that lead to longer car trips. Specifically, to what extent would respondents accept delays to everyday local car journeys if these were offset by reductions in NO2, greenhouse gas emissions or vehicular traffic, or by increases in active travel? Responses suggested high levels of acceptance of delay but this varied by nature of impact (less openness to increased active travel) and socio-demographic attribute (gender, educational attainment, car ownership, ethnicity, housing tenure, prior presence of local traffic restrictions). In particular, there were lower levels of delay acceptance amongst men, respondents without degree-level qualifications, and those in households with two or more cars. These findings are relevant to those communicating about traffic restrictions, in terms of which audiences they target and how they present impacts

Functional localisation of human sensory-motor cortex using magnetoencephalography

The 19 channel Neuromagnetometer system in the Clinical Neurophysiology Unit at Aston University is a multi-channel system, unique in the United Kingdom. A bite bar head localisation and MRI co-registration strategy which enabled accurate and reproducible localisation of MEG data into cortical space was developed. This afforded the opportunity to study magnetic fields of the human cortex generated by stimulation of peripheral nerve, by stimulation of visceral sensory receptors and by those evoked through voluntary finger movement. Initially, a study of sensory-motor evoked data was performed in a healthy control population. The techniques developed were then applied to patients who were to undergo neurosurgical intervention for the treatment of epilepsy and I or space occupying lesions. This enabled both validation of the effective accuracy of source localisation using MEG as well as to determine the clinical value of MEG in presurgical assessment of functional localisation in human cortex. The studies in this thesis have demonstrated that MEG can repeatedly and reliably locate sources contained within a single gyrus and thus potentially differentiate between disparate gyral activation. This ability is critical in the clinical application of any functional imaging technique; which is yet to be fully validated by any other 'non-invasive' functional imaging methodology. The technique was also applied to the study of visceral sensory representation in the cortex which yielded important data about the multiple cortical representation of visceral sensory function