Comparison of Extraction Protocols To Determine Differences in Wine-Extractable Tannin and Anthocyanin in <i>Vitis vinifera</i> L. cv. Shiraz and Cabernet Sauvignon Grapes

Cabernet Sauvignon and Shiraz grapes were sourced from different regions within Australia, and microvinified with a skin contact period of 6 days. Grape samples were extracted using two protocols: a 15% v/v ethanol, 10 g/L tartaric acid extract of gently crushed berries (wine-like, WL) and a 50% v/v ethanol, pH 2 extract of grape berry homogenate. It was found that in WL extracts, grape tannin and anthocyanin concentrations were strongly related to wine tannin, anthocyanin and color density achieved during the skin contact period. No relationship was observed for grape tannin concentration analyzed in homogenate extracts and wine tannin, but a strong, positive relationship was found for anthocyanin concentration. When the data obtained from homogenate extraction was treated separately by grape variety, a stronger relationship between grape and wine tannin concentration was observed. Tannin compositional analysis in wines indicated that higher tannin concentrations were due to the extraction of tannin of higher molecular mass during fermentation, most likely from grape skins

Assessing the geochemical and tectonic impacts of fluid-rock interaction in mid-crustal shear zones: a case study from the intracontinental Alice Springs Orogen, central Australia

The Reynolds–Anmatjira Ranges, central Australia, form part of a high-grade basement terrane dissected by intensely metasomatized transpressional shear zones active during the Ordovician–Carboniferous Alice Springs Orogeny. Unlike typical retrograde structures associated with discrete fluid flow, the mid-crustal setting and intracontinental nature of these shear systems present significant problems for the source and ingress mechanism of the fluid involved in their rehydration. To address these issues, we describe two detailed traverses across deformed and metasomatized basement rocks in this region, and interrogate their record of fluid–rock interaction from various perspectives. Both traverses combine structural and petrological observations with Zr-in-rutile and Ti-in-quartz thermobarometry, oxygen and hydrogen stable isotope analysis, and major, trace and rare earth element mobility trends. Each technique is critically evaluated for its utility in this study and its more widespread applicability to alternative field areas, providing a strategic framework for the general investigation of fluid-affected shear zones. Ultimately, the integrated data sets specify pressure–temperature conditions of ∼530 °C and 4–5 kbar, implying average apparent thermal gradients of 29–36 °C km−1 and depths of 14–18 km. Other characteristic features to emerge include strongly variable element mobilities and pronounced isotopic depletion fronts consistent with the alteration effects of an externally derived, non-equilibrium fluid. This is confirmed by calculated fluid compositions indicative of contributions from a fluid of meteoric origin, with estimated δ18O and δD values as low as 2.3‰ and −59.8‰, respectively. We propose that these surficial fluid signatures are imposed on the mid-crust by the prograde burial and dehydration of hydrothermally altered fault panels produced during pre-orogenic basin formation. Progressive fluid release with continued subsidence then leads to the accumulation of increasing fluid volumes in the vicinity of the brittle–ductile transition, promoting extensive hydration, metasomatism and reaction softening at the locus of stress transmission from plate-boundary sources. The sustained injection of externally derived fluids into refractory crustal material may thus stimulate a critical reduction in the long-term strength of the lithosphere, providing strong impetus for the initiation and advancement of intracontinental orogenesis.T. Raimondo, C. Clark, M. Hand and K. Faur

A new national chlamydia sentinel surveillance system in Australia: evaluation of the first stage of implementation

The Australian Collaboration for Chlamydia Enhanced Sentinel Surveillance (ACCESS) was established with funding from the Department Health and Ageing to trial monitoring the uptake and outcome of chlamydia testing in Australia. ACCESS involved 6 separate networks; 5 clinical networks involving sexual health services, family planning clinics, general practices, antenatal clinics, Aboriginal community controlled health services, and 1 laboratory network. An evaluation of ACCESS was undertaken in early 2010, 2 years after the program was funded. At the time of the evaluation, 76 of the 91 participating sites were contributing data. The jurisdictional distribution of the 76 sites generally matched the jurisdictional distribution of the Australian population. In 2008, the chlamydia testing rates in persons aged 16–29 years attending the 26 general practices was 4.2% in males and 7.0% in females. At the 25 sexual health services, the chlamydia testing rates in heterosexuals aged less than 25 years in 2008 was 77% in males and 74% in females. Between 2004 and 2008, the chlamydia positivity rate increased significantly in heterosexual females aged less than 25 years attending the sexual health services, from 11.5% to 14.1% (P < 0.01). Data completeness was above 85% for all core variables except Aboriginal and/or Torres Strait Islander status and country of birth, which ranged from 68%–100%, and 74%–100%, respectively, per network. There were delays in establishment of the system due to recruitment of 91 sites, multiple ethics applications and establishment of automated extraction programs in 10 different database systems, to transform clinic records into a common, pre-defined surveillance format. ACCESS has considerable potential as a mechanism toward supporting a better understanding of long-term trends in chlamydia notifications and to support policy and program delivery