Bathymetry and frontal system interactions influence seasonal foraging movements of lactating subantarctic fur seals from Marion Island

Sixteen lactating subantarctic fur seals Arctocephalus tropicalis were satellite-tracked during the winter of 2006 (n = 6), summer of 2006/07 (n = 6) and autumn/winter (n = 4) of 2007, from Marion Island, Southern Ocean. Despite varied individual movement patterns, a favoured foraging area lay to the northeast of the island. In contrast to findings for populations at similar latitudes, seals from Marion Island did not undertake short overnight foraging trips, but trips consistently went beyond 300 km from the island. This aligns with the at-sea duration of lactating seals’ foraging trips from temperate Amsterdam Island, but differs from subantarctic Crozet and Macquarie islands. Time spent at sea, maximum distances travelled and movement variation of tracks from the island varied seasonally. Faecal analysis suggests the diet comprised primarily myctophid fish with limited seasonal variation. Well-defined areas of restricted movement coincided with significant bathymetric features to the west/northwest of the Crozet Plateau, with the Del Caño Rise clearly being important. Positive and negative sea-surface height anomalies (compared to the mean) appeared to be preferred by most seals across seasons. Higher summer sea-surface temperatures correlated with the movements of some seals. Higher chlorophyll a concentrations dictated transit and foraging areas during summer. Bathymetrically influenced oceanographic variables likely explain these preferred long-distance eastward movements. The Îles Crozet and Marion island subantarctic fur seals differ in their foraging ecology despite being neighbours. Conversely, the subantarctic fur seal populations from the distant Amsterdam and Marion islands appear to be similarly influenced by such environmental factors.

Gradient edge map features for frontal face recognition under extreme illumination changes

Our aim in this paper is to robustly match frontal faces in the presence of extreme illumination changes, using only a single training image per person and a single probe image. In the illumination conditions we consider, which include those with the dominant light source placed behind and to the side of the user, directly above and pointing downwards or indeed below and pointing upwards, this is a most challenging problem. The presence of sharp cast shadows, large poorly illuminated regions of the face, quantum and quantization noise and other nuisance effects, makes it difficult to extract a sufficiently discriminative yet robust representation. We introduce a representation which is based on image gradient directions near robust edges which correspond to characteristic facial features. Robust edges are extracted using a cascade of processing steps, each of which seeks to harness further discriminative information or normalize for a particular source of extra-personal appearance variability. The proposed representation was evaluated on the extremely difficult YaleB data set. Unlike most of the previous work we include all available illuminations, perform training using a single image per person and match these also to a single probe image. In this challenging evaluation setup, the proposed gradient edge map achieved 0.8% error rate, demonstrating a nearly perfect receiver-operator characteristic curve behaviour. This is by far the best performance achieved in this setup reported in the literature, the best performing methods previously proposed attaining error rates of approximately 6–7%.

Phineas Gage

In 1848, as the result of a bizarre accident, Phineas Gage had most of the left frontal lobe of his brain destroyed. Although his surviving the injury by some 11.5 years made him a considerable medical curiosity, it was the changes to his behavior that made him important in the neurosciences. Gage's is actually one of the most important cases in the history of the neurosciences: it revealed for the first time that complex functions might be localized in the brain. Its status is indexed by its still being cited in about two-thirds of all psychology and related neuroscience textbooks and by the fact that studies were still being undertaken some 150 years after the accident to establish which parts of Gage's brain were damaged.

Revision of tertiary species of Anaskopora Wass (Bryozoa: Cribrimorpha)

The subgenus Anaskopora Wass, 1975 is raised to generic rank, separated from the genus Corbulipora, and redefined. The type species, Cribrilina elevata MacGillivray, 1895, is a Tertiary fossil from Victoria with small globular colonies formed principally by a special kind of interzooidal frontal budding. Other Tertiary fossil species with a similar colony structure, here assigned to Anaskopora, are Cribrilma cornuta MacGIllIvray, 1895 and Lepralia rotundata MacGillivray, 1895. Two further new Tertiary species, A. simplex and A. mesa, from Victoria and South Australia have small encrusting colonies. A key to species is given.

Inhibition and Phineas Gage : repression and Sigmund Freud

The similarities between the theories of thinking as inhibited action developed by David Ferrier and Sigmund Freud are examined in the context of the changes in the behavior of Phineas Gage, which Ferrier tried to explain with his inhibitory-motor theory. Johannes Müller's concept of will, its development by Alexander Bain, and Bain's influence on Ferrier's conceptualization of inhibitory centers localized in the frontal lobes are traced. Elements of the Bain-Ferrier theory found in Freud's theory of thinking, which do not derive from Brücke, Meynert, or Jackson, are itemized, and the implications of Freud's opting for a mechanism of inhibition that was basically excitatory is examined. Possible reasons for Ferrier's abandoning his concept of inhibitory centers are discussed and are contrasted with the reasons that Freud had for keeping to an excitatory conceptualization. The sensory-motor physiology of the day and its application to willing and thinking as inhibited action provide reasonably certain connections between Phineas Gage, David Ferrier, and Sigmund Freud.

Finite element modelling of metallic tubular crash structures with an explicit code

Numerous experimental studies have been carried out to investigate the collapse of tubular metallic crash structures under axial compression. Some simple theoretical models have been developed but these often assume one type of progressive collapse, which is not always representative of the real situation. Finite Element (FE) models, when further refined, have the potential to predict the actual collapse mode and how it influences the load-displacement and energy absorption characteristics. This paper describes an FE modelling investigation with the explicit code LS−DYNA. An automatic mesh generation programme written by the authors is used to set up shell and solid element tube models. Mesh specification issues and features relating to the contact and friction models are discussed in detail. The crush modes, load-deflection characteristics and energy absorption values found in the simulations are compared with a reasonable degree of correlation to those observed in a physical testing programme; however, improvements are still required.

Exechonella (Exechonellidae: Bryozoa, Cheilostomata) from the recent and miocene of Southern Australia

The cheilostome family Exechonellidae Harmer, 1957 is widely distributed in time and space. The genus Exechonella Duvergier, 1924 has a pan-tropical to subtropical distribution from the Eocene to the Recent and is represented by several Australian species from the Tertiary of Victoria and the Recent ofthe southern and eastern coasts. Some species exhibit a wide range of variation in morphological characters, and one, Exechonella papillata, "appears to be new, and is described here. Nearly all specimens are encrusting, but one Tertiary Victorian species has erect, cylindrical, branching colonies. Recent samples, from a depth range of 40-190 metres, include large colonies of several thousand zooids. Frontal wall structures include marginal septular pores connecting between the visceral and hypostegal coeloms, and frontal foramina. Avicularia and homologous structures derived from frontal septular pores are illustrated. The structure of the frontal foramina in different populations of Tertiary E. marginata, demonstrates a major development of hypostegal coelom not found in other species, but resembling that found in another exechonellid genus, Stephanopora Kirkpatrick, 1888.

Diet and habitat of the powerful owl (Ninox strenua) living near Melbourne

The diet of Powerful Owls (Ninox strenua) living at Christmas Hills, 35km north-east of Melbourne was examined by analysis of 686 regurgitated pellets collected over two years. An aid was also developed to help identify potential mammalian prey species based on hair and skeletal characteristics. The following features were found to be most useful in distinguishing between the three species of arboreal marsupials - Common Ringtail Possum (Pseudocheirus peregrinus), Common Brushtail Possum (Trichosurus vulpecula) and Sugar Glider (Petaurus breviceps): - Cross-sectional width of primary guard hairs. - The size and shape of the nasal, frontal, parietal and squamosal bones of the skull. - Dentition. The size and shape of the upper incisor, canine and premolar teeth. The size and shape of the lower incisor and premolar teeth. - The size of the humerus. The Sugar Glider has a much smaller humerus than that of the Common Ringtail Possum and the Common Brushtail Possum. In the Common Brushtail Possum the entepicondyle ends in a very sharp point but the Common Ringtail Possum this point is not as sharp. - The Common Ringtail Possum’s femur has a very prominent trochanter which projects further than that in the Common Brushtail Possum. The femur of the Sugar Glider is distinguished by having a very large depression between the condyle and the trochanter. - The Common Brushtail Possum’s scapula has a narrower lower blade (relative to length) than that in the Common Ringtail Possum. The scapula of the Sugar Glider is smaller in size than that of the other two possums.The pelvic girdle Of the Common Brushtail Possum has a much wider ischium than those of the Common Brushtail Possum and the Sugar Glider. The ilium of the Sugar is much narrower and smaller than that of the other two possums Mammalian prey was found in 89%, insects in 13% and birds in 10% of the pellets. Of the mammals, Common Ringtail Possums occurred most frequently in the pellets over the year. There was no seasonal difference in the frequency of occurrence of Common Ringtail Possums and Sugar Gliders in pellets. However, Common Brushtail Possums were more likely to be taken in spring than in the other seasons. More adult Common Ringtail Possums were taken as prey than were other age classes over the year, except in summer when high numbers of young were consumed by the owls. The habitat of the Powerful Owl was examined by ground surveys and spotlight surveys in sixteen sites within the Warrandyte-Kinglake Nature Conservation Link. Four categories of survey sites were chosen with the following features. Category A - Sites with a dense understorey of shrubs and small trees, as well as many old trees (>10/ha) which might be suitable for nest hollows. Category B - Sites which lacked a dense understorey of shrubs and small trees and containing few or no old trees suitable for nest hollows. Category C - Sites with a dense understorey of shrubs and small trees but containing few or no old trees suitable for nest hollows. Category D - Sites which lacked a dense understorey of shrubs and small trees but having old trees (>10/ha) which might be suitable for nest hollows. High prey densities strongly correlated with the presence of hollows at these sites. In the light of the results, management recommendations were made for the future conservation of the Powerful Owls living at Christmas Hills. The following recommendations were particularly important: 1. Cleared or semi - cleared land within the Warrandyte Kinglake Nature Conservation Link be revegetated using indigenous species of eucalypts and waffles in order to provide a contiguous native forest corridor for the movement of possums and gliders between the Yarra River Valley and the Kinglake Plateau. 2. Continued planting of Eucalyptus spp. and Acacia spp. in the forested areas of the Warrandyte-Kinglake Nature Conservation Link. 3. Continued protection of healthy living trees to provide a continuous supply of hollow trees. 4. No falling of dead standing trees for firewood collecting as these can provide nest hollows for prey species of the Powerful Owl.

Spatial and temporal disparities in aurally aided visual search

Research over the last decade has shown that auditorily cuing the location of visual targets reduces the time taken to locate and identify targets for both free-field and virtually presented sounds. The first study conducted for this thesis confirmed these findings over an extensive region of free-field space. However, the number of sound locations that are measured and stored in the data library of most 3-D audio spatial systems is limited, so that there is often a discrepancy in position between the cued and physical location of the target. Sampling limitations in the systems also produce temporal delays in which the stored data can be conveyed to operators. To investigate the effects of spatial and temporal disparities in audio cuing of visual search, and to provide evidence to alleviate concerns that psychological research lags behind the capabilities to design and implement synthetic interfaces, experiments were conducted to examine (a) the magnitude of spatial separation, and (b) the duration of temporal delay that intervened between auditory spatial cues and visual targets to alter response times to locate targets and discriminate their shape, relative to when the stimuli were spatially aligned, and temporally synchronised, respectively. Participants listened to free-field sound localisation cues that were presented with a single, highly visible target that could appear anywhere across 360° of azimuthal space on the vertical mid-line (spatial separation), or extended to 45° above and below the vertical mid-line (temporal delay). A vertical or horizontal spatial separation of 40° between the stimuli significantly increased response times, while separations of 30° or less did not reach significance. Response times were slowed at most target locations when auditory cues occurred 770 msecs prior to the appearance of targets, but not with similar durations of temporal delay (i.e., 440 msecs or less). When sounds followed the appearance of targets, the stimulus onset asynchrony that affected response times was dependent on target location, and ranged from 440 msecs at higher elevations and rearward of participants, to 1,100 msecs on the vertical mid-line. If targets appeared in the frontal field of view, no delay of acoustical stimulation affected performance. Finally, when conditions of spatial separation and temporal delay were combined, visual search times were degraded with a shorter stimulus onset asynchrony than when only the temporal relationship between the stimuli was varied, but responses to spatial separation were unaffected. The implications of the results for the development of synthetic audio spatial systems to aid visual search tasks was discussed.

The neuroanatomical correlates of subjective wellbeing following head injury

The thesis found results supporting the involvement of the Right Frontal area of the brain in the subjective wellbeing (SWB) of individuals. Additional results suggested SWB is dependent upon Core Affect, itself dependent upon the Right Parietal area of the brain. These results provide evidence that SWB and Core Affect are based upon a neurological substrate. The portfolio investigated the association between chronic medical conditions and anxiety disorders, and how the occurence of anxiety issues can affect overall psychological adjustment to illness.