A calibration of cellulose isotopes in modern prostrate Nothofagus and its application to fossil material from Antarctica.

Carbon and oxygen isotopes (δC and δO) in tree rings are widely used to reconstruct palaeoclimate variables such as temperature during the Holocene (12 thousand years ago - present), and are used increasingly in deeper time. However, their use is largely restricted to arboreal trees, which excludes potentially important data from prostrate trees and shrubs, which grow in high latitude and altitude end-member environments. Here, we calibrate the use of δC and δO as climatic archives in two modern species of southern beech (Nothofagus) from Tierra del Fuego, Chile, at the southern limit of their current range.

Temperate rainforests near the South Pole during peak Cretaceous warmth.

The mid-Cretaceous period was one of the warmest intervals of the past 140 million years, driven by atmospheric carbon dioxide levels of around 1,000 parts per million by volume. In the near absence of proximal geological records from south of the Antarctic Circle, it is disputed whether polar ice could exist under such environmental conditions. Here we use a sedimentary sequence recovered from the West Antarctic shelf-the southernmost Cretaceous record reported so far-and show that a temperate lowland rainforest environment existed at a palaeolatitude of about 82° S during the Turonian-Santonian age (92 to 83 million years ago).

Macrofossil evidence for a rapid and severe Cretaceous-Paleogene mass extinction in Antarctica.

Debate continues about the nature of the Cretaceous-Paleogene (K-Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low latitudes towards the poles.

Medication to prevent breast cancer--too much to swallow?

Selective oestrogen receptor modulators effectively reduce breast cancer in women at moderate to high risk, so why aren't they being discussed routinely?

Reducing time to diagnosis does not improve outcomes for women with symptomatic ovarian cancer: a report from the Australian Ovarian Cancer Study Group.

Purpose: To determine if time to diagnosis is associated with stage of disease at diagnosis or survival among women with symptomatic ovarian cancer.

Methods: A representative sample of Australian women (n = 1,463) with ovarian cancer diagnosed between 2002 and 2005 who participated in a population-based case-control study were interviewed regarding the events leading to their diagnosis and were observed for mortality for 5 years.

Results: Of the 1,318 women (90%) who presented to a medical practitioner with symptoms, 55% presented within 1 month, 70% in less than 2 months, and 92% within 6 months of symptom onset.

Are there pre-Quaternary geological analogues for a future greenhouse warming?

Given the inherent uncertainties in predicting how climate and environments will respond to anthropogenic emissions of greenhouse gases, it would be beneficial to society if science could identify geological analogues to the human race's current grand climate experiment. This has been a focus of the geological and palaeoclimate communities over the last 30 years, with many scientific papers claiming that intervals in Earth history can be used as an analogue for future climate change. Using a coupled ocean-atmosphere modelling approach, we test this assertion for the most probable pre-Quaternary candidates of the last 100 million years: the Mid- and Late Cretaceous, the Palaeocene-Eocene Thermal Maximum (PETM), the Early Eocene, as well as warm intervals within the Miocene and Pliocene epochs.

Pathways to the diagnosis of epithelial ovarian cancer in Australia.

Objective: To describe the diagnostic pathways experienced by a large, representative group of Australian women with ovarian cancer, and to document the time between first presentation to a medical professional and clinical diagnosis.

Design, Setting And Participants: 1463 women with epithelial ovarian cancer from an Australia-wide population-based study (2002-2005) completed a telephone interview in which they described the events that led to the diagnosis of their cancer.

Main Outcome Measures: Number and type of doctors consulted, investigations performed, referral patterns and the time from first presentation to diagnosis.

Population screening and early detection of ovarian cancer in asymptomatic women.

The National Breast and Ovarian Cancer Centre position statement: 'Population screening and early detection of ovarian cancer in asymptomatic women', was developed and agreed following a Forum in February 2009 attended by key Australian stakeholders. The final position statement and supporting background information have been endorsed by key Australian colleges and agencies. Position statement on population screening and early detection of ovarian cancer in asymptomatic women: 1) There is currently no evidence that any test, including pelvic examination, CA125 or other biomarkers, ultrasound (including transvaginal ultrasound), or combination of tests, results in reduced mortality from ovarian cancer.

Introduction. Pliocene climate, processes and problems.

Climate predictions produced by numerical climate models, often referred to as general circulation models (GCMs), suggest that by the end of the twenty-first century global mean annual surface air temperatures will increase by 1.1-6.4 degrees C.