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Mineralogical, chemical, and spectroscopic properties of chrysoberyl crystals recovered from sapphire placer deposits, related to Tertiary volcanic rocks, in the New England gem fields in New South Wales (NSW), Australia, are presented. The samples appeared yellow, yellowish brown, or brown in transmitted light, and some crystals revealed a distinct sectorial zoning between brown i (011) and yellow o (111) growth areas. In reflected light, the i sectors showed a whitish appearance, and cabochon-cut samples with larger whitish i sectors displayed chatoyancy. On the basis of morphological properties, trace-element contents, and absorption spectra, the chrysoberyl samples were subdivided into four different groups, possibly originating from different host rocks. The largest such group, comprised of samples with distinct sectorial color zoning, also revealed a pronounced variation in trace-element levels of titanium, niobium, and tantalum between the different growth sectors. Smaller variations were found for boron, magnesium, and iron, and almost no variation was observed for gallium. [ABSTRACT FROM AUTHOR]

ABSTRACT We have mapped 20 spectral lines in the Central Molecular Zone (CMZ) around the Galactic Centre, emitting from 85.3 to 93.3 GHz. This work used the 22-m Mopra radio telescope in Australia, equipped with the 8-GHz bandwidth University of New South Wales-Mopra Spectrometer (UNSW-MOPS) digital filter bank, obtaining ∼2 km s−1 spectral and ∼40 arcsec spatial resolution. The lines measured include emission from the c-C3H2, CH3CCH, HOCO+, SO, H13CN, H13CO+, SO, H13NC, C2H, HNCO, HCN, HCO+, HNC, HC3N, 13CS and N2H+ molecules. The area covered is Galactic longitude −07 to 18 and latitude −03 to 02, including the bright dust cores around Sgr A, Sgr B2, Sgr C and G1.6−0.025. We present images from this study and conduct a principal component analysis on the integrated emission from the brightest eight lines. This is dominated by the first component, showing that the large-scale distribution of all molecules is very similar. We examine the line ratios and optical depths in selected apertures around the bright dust cores, as well as for the complete mapped region of the CMZ. We highlight the behaviour of the bright HCN, HNC and HCO+ line emission, together with that from the 13C isotopologues of these species, and compare the behaviour with that found in extragalactic sources where the emission is unresolved spatially. We also find that the isotopologue line ratios (e.g. HCO+/H13CO+) rise significantly with increasing redshifted velocity in some locations. Line luminosities are also calculated and compared to that of CO, as well as to line luminosities determined for external galaxies. [ABSTRACT FROM AUTHOR]

Abstract: Mid-infrared diffuse reflectance spectroscopy (MIR-DRS, 2500 to 25000 nm) can provide rapid, cheap and relatively accurate predictions for a number of soil properties. This paper examines the ability of MIR-DRS to predict various soil chemical properties with emphasis on the elucidation of possible mechanisms of prediction. Three datasets from the states of Queensland, New South Wales, and Victoria, Australia were used in this study. MIR is able to predict fundamental soil properties related to soil matrix or solid constituents and soil solution concentrations which are in equilibrium with the solid phases. Basic soil organic and mineral constituents are well predicted: cation exchange capacity, clay content, organic and total C, and total N. Chemical properties that are related to the mineral and organic components can also be predicted, including: total K, total P, elemental Fe, Si, and Al. Soil pH appears to be related to the soil constituents from its relationship with the exchange sites. Due to the differences in the origins of the soil and in the laboratory measurement procedures, calibration functions from one region do not perform well on another one. Local calibration is preferred to avoid the measurement biases between laboratories, and the calibrated functions are more specific to the soil types in an area. [Copyright &y& Elsevier]

Raman spectroscopy is used to identify minerals in isolated sealed inclusion chambers in some New South Wales (Australia) diamonds and to determine the remnant internal pressure on each inclusion with values of each: 3.03, 3.31 and 3.54 - 3.62 GPa for coesite, 0.42, 1.36 and 2.3 GPa for diopsidic omphacite, and 0.8 GPa for grossular garnet, each determination for a different uncut stone. The diamond stress due to remnant pressure was found to be proportional to the maximum strain birefringence around each inclusion, as measured by the Berek compensator, with the constant (K = 1000 / 5.8, R2 = 0.93) independent of the inclusion mineral, size, orientation and shape within the limits of error. Thus, simple birefringence measurements of diamond adjacent to inclusions can be used to estimate remnant pressures on inclusions. The calibration shows that one of the stressed diamonds has an anomalously low strain birefringence. [ABSTRACT FROM AUTHOR]

Integrating imaging spectroscopy (445­2543 nm) and geographic information systems for post-disaster management: a case of hailstorm damage in Sydney S. BHASKARAN Faculty of Engineering and Surveying, University of Southern Queensland, Toowoomba, Queensland 4350, Australia; e-mail: bhaskar@usq.edu.au B. DATT Office of Space Science & Applications and Earth Observation Centre, CSIRO, Sydney, Australia B. FORSTER School of Surveying and Spatial Information Systems, University of New South Wales, Australia T. NEAL and M. BROWN Corporate Strategy Division, New South Wales Fire Brigades, Sydney, Australia (Received 7 January 2002; in final form 21 August 2003 ) Abstract. This paper demonstrates a methodology for the analysis and integration of airborne hyperspectral sensor data (445­2543 nm) with GIS data in order to develop a vulnerability map which has the potential to assist in decision making during post-disaster emergency operations. Hailstorms pose a threat to people as well as property in Sydney, Australia. Emergency planning demands current, large-scale spatio-temporal information on urban areas that may be susceptible to hailstones. Several regions, dominated by less resistant roofing materials, have a higher vulnerability to hailstorm damage than others. Post-disaster operations must focus on allocating dynamic resources to these areas. Remote sensing data, particularly airborne hyperspec- tral sensor data, consist of spectral bands with narrow bandwidths, and have the potential to quantify and distinguish between urban features such as roofing materials and other man-made features. A spectral library of surface materials from urban areas was created by using a full range spectroradiometer. The image was atmospherically corrected using the empirical line method. A spectral angle mapper (SAM) method, which is an automated method for comparing image spectra to laboratory spectra, was used to develop a classification map that shows the distribution of roofing materials with different resistances to hailstones. Surface truthing yielded high percentage accuracy. Spatial overlay technique was performed in a GIS environment where several types of cartographic data such as special hazard locations, population density, data about less mobile people and the street network were overlaid on the classified geo-referenced hyperspectral image. The integrated database product, which merges high quality spectral information and cartographic GIS data, has vast potential to assist emergency organizations, city planners and decision makers in formulating plans and strategies for resource management. International Journal of Remote Sensing ISSN 0143-1161 print/ISSN 1366-5901 online # 2004 Taylor & Francis Ltd http://www.tandf.co.uk/journals DOI: 10.1080/01431160310001642331 INT . J . REMOTE SENSING , 10 JULY , 2004, VOL . 25, NO. 13, 2625­2639. 1. Introduction Hailstorms can cause substantial damage to property anywhere in the world. For instance, on 14 April 1999, a thunderstorm was detected forming approxi- mately 115 km south of Sydney, Australia, near Nowra. Within 25 minutes the storm unleashed a maelstrom of icy fury, as the largest hailstones ever recorded in Sydney crashed down from the skies at over 200 km h2 1 . The storm carved a path of destruction resulting in an estimated damage bill of 1.5 billion dollars (Fire News 1999). Table 1 shows the total estimated financial losses incurred by hailstorms and other catastrophes from 1967 to 1998. While the prevention of hailstorms is a myth, the management of dynamic resources for rescue and post disaster operations is an important issue. From a disaster management perspective it is vital to develop a database that shows areas with different degrees of vulnerability from hailstorms. Hailstorm vulnerability can be assessed in different ways, one of which is by mapping the type of roofing material used for constructions, since different roofing materials have varying degrees of resistance to hailstones. There is a high correlation of damaged roofs to the material composition of the roofing material, which in turn determines their resistance to hailstones (Andrews and Blong 1997, Vorobieff et al. date unknown). The roof is the first point of impact from the hailstorm and thereafter severe damage is caused to the houses and property. Various studies indicate that tiles, gutters, windows, brittle cladding materials and metal sheeting are all at risk during heavy hail. Thin metal sheeting is dented or even penetrated, while tiles develop hairline cracks and are often shattered under the impact of hailstones. Age and impact location are important factors for many roofing materials (Vorobief et al. date unknown). A study carried out by Andrews and Blong (1997) reported that tile roofs were the most commonly damaged roof type. The study ranked roof materials in decreasing order of vulnerability to damage: aluminium, fibro, slate, tiles and iron. Roofs contributed as one of the major cost items accounting for 22% of the total cost. Research in the past has explored the use of remote sensing data to study urban surfaces mainly by means of classification of multi-spectral data materials (Lo 1997, Forster 1983, Heiden et al. 2001). All these studies confirmed the inadequacy of spectral resolution of broadband sensors to detect and map urban features. Bhaskaran et al. (2001a) demonstrated a methodology that used airborne remote sensor data to map vulnerability from hailstorms in Sydney. Furthermore, urban Table 1. Largest Australian insured catastrophic losses 1967­1998 (Insurance Council of Australia). Event Location Date Insured loss (A$ million) Earthquake Newcastle 1989 1125 Cyclone Tracy Darwin 1975 835 Hailstorm Sydney 1990 385 Cyclone Wanda Brisbane 1974 330 Bushfires Victoria, South Australia 1983 325 Hailstorm Brisbane 1985 300 Thunderstorm Sydney 1991 225 Hailstorm Sydney 1986 160 Hailstorm NSW 1976 130 Cyclone Madge Northern Australia 1973 150 Cyclone Althea Townsville 1971 150 2626 S. Bhaskaran et al. [ABSTRACT FROM AUTHOR]

A numerical study was conducted to investigate the sediment dynamics in a geographically complex estuary, the Sydney Harbour Estuary (SHE). The SHE is a good example of a microtidal estuary, with irregular shorelines and a complex bathymetry, characterized by many headlands and islands forming a meandering main channel. Horizontal sediment transport showed a local estuarine turbidity maximum (ETM) as a result of complex topography, independent of salinity fields and river flows during dry weather. The along-estuary advection of sediment was mainly driven by the mean advection, with a minor contribution by tidal pumping. Mean advection associated with barotropic forcing drives sediment flux seaward in the upper estuary and landward in the middle estuary, leading to a longitudinal convergence of sediment transport, without upstream or downstream migration of ETM during high river flows. The interactions between tidal currents, complex topography and asymmetric vertical mixing led to spring-neap and flood-ebb variations in sediment distribution. The Singular Spectrum Analysis (SSA) method was used to calculate the relative contributions of the identified environmental forcing frequencies (tidal range, tidal frequency, river discharges, wind stress) to the variability in suspended-sediment concentration. Tidal frequency and river discharges were the major contributors to this variability. Tidal range made the highest contribution in the middle estuary, where the ETM was located, driving the spring-neap cycle of the ETM. • Sediment flux variability was induced by the interactions between channel topography, tidal forcing and vertical mixing. • Mean advection induced sediment flux results in a spatially fixed estuary turbidity maximum. • Contributions of identified environmental forcing frequencies on SSC variability were evaluated over the whole estuary. [ABSTRACT FROM AUTHOR]

A decade ahead of their time, von Schantz et al. united sexual selection and free radical biology by identifying causal links between deep-rooted physiological processes that dictate resistance to toxic waste from oxidative metabolism (reactive oxygen species, ROS), and phenotypic traits, such as ornaments. Ten years later, these ideas have still only been tested with indirect estimates of free radical levels (oxidative stress) subsequent to the action of innate and dietary antioxidants. Here, we measure net superoxide (a selection pressure for antioxidant production) and experimentally manipulate superoxide antioxidation using a synthetic mimetic of superoxide dismutase (SOD), Eukarion 134 (EUK). We then measure the toxic effect of superoxide in terms of DNA erosion and concomitant loss of male breeding coloration in the lizard, Ctenophorus pictus. Control males suffered more DNA damage than EUK males. Spectroradiometry showed that male coloration is lost in relation to superoxide and covaries with DNA erosion; in control males, these variables explained loss of color, whereas in EUK males, the fading of coloration was unaffected by superoxide and unrelated to DNA damage. Thus, EUK's powerful antioxidation removes the erosion effect of superoxide on coloration and experimentally verifies the prediction that colors reflect innate capacity for antioxidation., (© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.)

Australian crab spiders Thomisus spectabilis ambush pollinating insects, such as honeybees (Apis mellifera) on flowers, and can change their body colour between yellow and white. It is traditionally assumed that the spiders change their colour to match the flower colour, thus rendering them cryptic to insect prey. Here, we test this assumption combining state-of-the-art knowledge of bee vision and behavioural experiments. In the field, yellow spiders are only found on yellow daisies (Chrysanthemum frutescens), whereas white spiders are found on yellow and white daisies. These field patterns were confirmed in the laboratory. When given the choice between white and yellow daisies, yellow spiders preferred yellow daisies, whereas white spiders showed only a slight but non-significant preference for white flowers. Thus, T. spectabilis select background colours according to their own body colour. When viewed from a distance, bees use an achromatic signal produced by their green receptors for target detection. Through this visual channel, white spiders on white flowers, and yellow spiders on yellow flowers are virtually undetectable. From a closer distance of a few centimetres, when bees evaluate colour contrast, the combination of spider colour against different flower backgrounds affected the response of honeybees, but not in ways predicted by a classical crypsis/conspicuousness interpretation. Yellow spiders on yellow flowers are not perfectly matched when interpreted through the colour vision of a honeybee. Nevertheless, honeybees showed indifference to the presence of a spider, equally landing on vacant or spider-occupied flowers. Likewise, white spiders are poorly hidden on white flowers, as white spiders reflect ultraviolet light strongly, while white flowers do not. Surprisingly, bees are attracted to this contrast, and significantly more honeybees preferred white flowers occupied by white spiders. White spiders on yellow flowers produce the highest colour contrast and bees again preferred spider-occupied flowers. Yellow spiders on white flowers were the only pairing where bees rejected spider-occupied flowers, especially in cases where the contrast between the two was relatively strong. Thus, T. spectabilis select flower colours adaptively in a way that deceives honeybees, or at least does not deter them.

Light-induced plasticity in plant morphology is considered adaptive in terrestrial habitats that vary in light, but remains unexplored for marine habitats. This is despite similar modes of growth, development and photosynthetic equipment in terrestrial and marine photoautotrophs and similarly dynamic light environments. We tested whether manipulations of light quantity and quality induce morphological plasticity in the marine macroalga, Asparagopsis armata. Using multivariate analyses (principal components analyses and multivariate analyses of covariance), we show that correlated morphological traits underlie a fundamental growth strategy characterized by the production of phalanx and guerrilla phenotypes in environments that mimic light and shade respectively. This foraging response is not under simple genetic or environmental control, but influenced by interactions between genotype and environment. Evidence of plasticity and genetic variation in plasticity in a marine modular organism generates additional, testable hypotheses on the ecological consequences of variation in growth form that may further explain the evolution of plasticity.