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Because the deep Earth is not directly accessible, geoscientists rely on laboratory experiments and computer models in order to understand the properties of minerals at the extreme pressure and temperature conditions of deep crust, the mantle and the core. In the field of high-pressure mineral physics and chemistry, we use our understanding of mineral properties, stress–strain relationships in multiphase rocks, and processes such as partial melting at high pressures and temperatures, to interpret geophysical observations of the deep Earth. Studies have constrained the pressure sensitivity of deformation of minerals such as olivine under subduction zone conditions, and the effect of pressure on slip systems in high-pressure minerals such as wadsleyite and perovskite. These results have important implications for the variation of mantle viscosity with depth, the geodynamic interpretation of seismic anisotropy, and changes in mantle rheology as a function of composition. However, the rheology and dynamics of the deep Earth are still poorly understood. Fortunately, technical development has been undertaken over the past 10 years in the USA, and scientific advances have been helped by the development of high-P–T deformation apparatus, such as the large volume multi-anvil deformation apparatus known as the D-DIA. This has opened up the possibility of determining physical and chemical processes in the upper mantle, and into the mantle transition zone. To participate in this exciting new area of research, we are now developing a high-pressure facility at the Australian Synchrotron. In this overview paper, we describe the background and current research that is being conducted in other synchrotron high-pressure facilities and what will now be possible for the Australian Synchrotron. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Few therapies are currently available to treat keratosis pilaris atrophicans (KPA), a spectrum of disorders which includes ulerythema ophryogenes and atrophoderma vermiculata. OBJECTIVE: To evaluate the response of KPA to treatment with the pulsed dye laser (PDL) with regard to improvements in erythema and skin roughness, treatment tolerability, and side effects. METHODS: Treatment of all facial areas involved with KPA with the PDL at 585 nm was evaluated in 12 patients. Prior to and after each treatment skin erythema was estimated using an erythema meter, and skin roughness was analysed using micrometer evaluation of a skin surface biopsy taken from the same mapped area and anaysed by computer to calculate the roughness profile. RESULTS: Patients received 2 to 8 treatments with the PDL with energies ranging from 6.0 to 7.5 J/cm[sup 2]. Clinical improvement was noted in all patients with significant reduction in erythema scores. Pre-treatment scores ranged from 4 to 13 (mean 8.3) and post-treatment 0 to 8 (mean 3.1) (P < 0.05). Improvements in skin roughness were clinically apparent in all but two patients, but these were not significant on evaluation of skin surface biopsies. Treatment was generally well tolerated, and side effects other than local pain during treatment were very few. CONCLUSION: PDL treatment appears to be a safe and effective treatment for the erythema associated with KPA but does not give significant improvement in associated skin roughness. [ABSTRACT FROM AUTHOR]

This paper demonstrates how remote sensing can be used to aid the general approach of landscape archaeology. The methodology and results of a project attempting to elucidate links and controls between environmental change and long-term social change in southern Madagascar are outlined. Multi-seasonal Landsat TM images, SPOT panchromatic and ERS-1 SAR images are used to produce a number of outputs. These include a general landcover map, a detailed map of forest extent and type (split into primary, secondary, and regenerative), field pattern maps, and predictions of archaeological site locations based on spectral properties of known sites. From these maps it has been possible to predict possible former settlements, archaeological sites, and forests of sacred significance. [ABSTRACT FROM AUTHOR]

Accidental hypothermia and heatstroke are more common in aged populations. While peripheral factors are undoubtedly important to the high incidence of dysthermia in the aged, alterations in central temperature controls associated with aging may be primarily responsible. It has been shown that the sensitivity of the hypothalamus to neurotransmitters is changed in aged animals, and it may be that similar alterations in central temperature controls underlie the increased susceptibility to dysthermia. As a first step in testing this hypothesis the responsiveness of central temperature controls of aged squirrel monkeys to taurine, a putative inhibitory neurotransmitter or neuromodulator, was tested. Intracerebroventricular (i.c.v.) administration of this sulfonated amino acid (0.5-4.0 mg) produced dose-related hypothermia in squirrel monkeys over nine years of age in a thermoneutral environment (23°C). Younger animals had significantly smaller hypothermias. In a hot environment (30°C) there were no significant differences between the temperature decreases of the two age groups after any dose. However, in a cold environment (17°C), in which young animals developed slightly larger hypothermias than in the thermoneutral environment, core temperature of the aged squirrel monkeys dropped so rapidly in response to even the lowest dose that they had to be removed and warmed to prevent death by hypothermia. The temperature controls of the aged squirrel monkey appear to be extrememly sensitive to taurine. The findings indicate that a rise in central taurine concentration in old primates can, in a cold environment, produce an effect very much like accidental hypothermia in aged man. [ABSTRACT FROM PUBLISHER]

The Advanced Light Source (ALS) is a 1.9-GeV, third-generation synchrotron optimized for the production of VUV and soft X-rays from undulators. There is also a hard X-ray program at the ALS, which is based around three 6-T superconducting bending magnets [1] that shift the critical energy from 3 keV to 12 keV. The extreme conditions beamline at the ALS is situated on Beamline 12.2.2, which benefits from radiation produced by one of these superbend sources. The beamline is designed for X-ray diffraction, X-ray spectroscopy, and X-ray imaging of samples held in diamond-anvil high-pressure cells (DACs). In a DAC, samples are on the order of 10 to 50 μm in diameter and 10 to 30 μm thick and are contained in a metal gasket of typical inner diameters of 100 to 150 μm. For high-quality diffraction patterns with little or no contamination from diffraction from the gasket, the X-ray beam size needs to be on the order of 10 μm × 10 μm. [ABSTRACT FROM AUTHOR]