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Tenascin-X is a large extracellular matrix glycoprotein that is widely distributed within connective tissues and is associated with an autosomal recessive type of Ehlers-Danlos syndrome (EDS). Tenascin-X represents the first EDS susceptibility gene that does not code for a fibrillar collagen or collagen-processing enzyme. We describe a paediatric case of tenascin-X deficiency and review the literature. [ABSTRACT FROM AUTHOR]

X-ray diffraction measurements of natural talc plus water at combined pressures and temperatures of 0-15 GPa and 23-400 °C reveal the presence of a structural change that could be interpreted as a new high-pressure phase at 4.0 (±0.5) GPa, and raise the possibility that the newly inferred phase transition takes place in cold subducting slabs as a precursor to appearance of the 10 Å phase of talc. [ABSTRACT FROM AUTHOR]

A tensonometer for stretching metal foils has been constructed for the study of strain broadening in X-ray diffraction line profiles. This device, which is designed for use on powder diffractometers and was tested on Station 2.3 at Daresbury Laboratory, allows in situ measurements to be performed on samples under stress. It can be used for data collection in either transmission or reflection modes using either symmetric or asymmetric diffraction geometries. As a test case, measurements were carried out on an 18 µm-thick copper foil experiencing strain levels of up to 5% using both symmetric reflection and symmetric transmission diffraction. All the diffraction profiles displayed peak broadening and asymmetry which increased with strain. The measured profiles were analysed by the fundamental-parameters approach using the TOPAS peak-fitting software. All the observed broadened profiles were modelled by convoluting a refineable diffraction profile, representing the dislocation and crystallite size broadening, with a fixed instrumental profile predetermined using high-quality LaB6 reference powder. The deconvolution process yielded `pure' sample integral breadths and asymmetry results which displayed a strong dependence on applied strain and increased almost linearly with applied strain. Assuming crystallite size broadening in combination with dislocation broadening arising from f.c.c. a/2〈110〉{111} dislocations, the variation of mechanical property with strain has been extracted. The observation of both peak asymmetry and broadening has been interpreted as a manifestation of a cellular structure with cell walls and cell interiors possessing high and low dislocation densities. [ABSTRACT FROM AUTHOR]

Crisp expanded wafers were produced from extruded pellets containing specialty starches and flours derived from peas, lentils, corn and blends of lentils and corn. The density, hardness and consumer acceptability of the wafers varied with the different ingredients. The most acceptable products were produced from corn, lentils and blends of these two ingredients. The weight, density, stiffness and hardness of the wafers increased with the proportion of lentil flour used to make them. Sensory analysis suggested that consumer acceptability was optimal for blends containing between 40 and 80% of lentil flour. Stiffness and fracture force measured by texture profile analysis were correlated with the sensory attributes of hardness and toughness. The glycemic potential measured by in vitro digestion of the wafers was lower for the 100% lentil wafers compared with the 100% corn wafers because of the amount of starch in the grain. For combinations of corn and lentils, the carbohydrate digestion rate, and hence the glycemic potential, was lower than for either 100% corn or 100% lentil wafers. Blending of selected cereal flour ingredients should be a useful method for reducing the glycemic impact of cooked starchy snacks. [ABSTRACT FROM AUTHOR]

Examines equation of state measurements of chlorite, pyrophyllite and talc. Room temperature compressibility of chlorite; Thermal expansivity of chlorite; Implications of data for phase stabilities in the earth.

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]