Ancient climates on Earth may have been more sensitive to carbon dioxide than was previously thought, according to an analysis of nahcolite crystals found in Colorado's Green River Formation, formed 50 million years old during a hothouse climate.

Scientists found that CO2 levels during this time may have been as low as 680 parts per million (ppm), nearly half the 1,125 ppm predicted by previous experiments. The new data suggests that past predictions significantly underestimate the impact of greenhouse warming and that Earth's climate may be more sensitive to increased carbon dioxide than was once thought

Scientists have found that people infected by the dengue virus but showing no clinical symptoms can actually infect mosquitoes that bite them. It appears that these asymptomatic people - who, together with mildly symptomatic patients, represent three-quarters of all dengue infections - could be involved in the transmission chain of the virus. 

The ice-covered Arctic Ocean is a more important factor concerning the concentration of the greenhouse gas methane in the atmosphere than previously assumed. Experts from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI) report on the newly discovered interactions between the atmosphere, sea ice and the ocean in a recent online study in the journal Nature's Scientific Reports.

The National Institutes of Natural Sciences National Institute for Fusion Science applied the "Momentary Heating Propagation Method" to the DIII-D tokamak device operated for the United States Office of Science, Department of Energy, by the General Atomics and made the important discovery of a new plasma confinement state. This discovery was introduced in the November 4, 2015, issue of Scientific Reports, a journal of the British science journal Nature group, in an article titled "Self-regulated oscillation of transport and topology of magnetic islands in toroidal plasmas."

Researchers have found more than half of the public datasets provided with scientific papers are incomplete, which prevents reproducibility tests and follow-up studies.

However, slight improvements to research practices could make a big difference.

Lead researcher Dr Dominique Roche from The Australian National University (ANU) said many peer-reviewed biological journals now require authors to publicly archive their data when a paper is published.

This is professor Loeske Kruuk. Credit: Stuart Hay, ANU

A new study strengthens growing evidence that Mycoplasma genitalium (MG) is a sexually transmitted infection (STI). The findings are recently published in the International Journal of Epidemiology.

Analyses of over 4500 of urine samples from Britain's third National Survey of Sexual Attitudes and Lifestyles (Natsal-3) showed that MG was prevalent in up to 1% of the general population aged 16-44, who had reported at least one sexual partner. Prevalence was much higher in those who had reported more than four sexual partners in the past year -- 5.2% in men and 3.1% in women. Absence of the infection in over 200 16-17 year olds who had not had vaginal, anal, or oral sex provided further evidence that MG is transmitted sexually.