On 4 July, NASA intends to finish a job that started with the agency’s Galileo mission 21 years ago. At 8:18 p.m. Pacific time, the Juno spacecraft will ignite its main engine for 35 minutes and nudge itself into orbit around Jupiter. If all goes well, it will eventually slip into an even tighter path that whizzes as close as 4,200 kilometres above the planet’s roiling cloud-tops — while dodging as much of the lethal radiation in the planet’s belts as possible.

It was the result that most scientists didn’t want. The United Kingdom’s vote to leave the European Union has plunged it into political and economic uncertainty — and left researchers worried over the future of their funding and collaborations, the UK’s participation in major European research programmes, and the freedom of movement and employment status of thousands of scientists.

Zika virus is a member of the flavivirus genus that had not been associated with severe disease in humans until the recent outbreaks, when it was linked to microcephaly in newborns in Brazil and to Guillain-Barré syndrome in adults in French Polynesia.

Worldwide heavy oil and bitumen deposits amount to 9 trillion barrels of oil distributed in over 280 basins around the world, with Canada home to oil sands deposits of 1.7 trillion barrels. The global development of this resource and the increase in oil production from oil sands has caused environmental concerns over the presence of toxic compounds in nearby ecosystems and acid deposition. The contribution of oil sands exploration to secondary organic aerosol formation, an important component of atmospheric particulate matter that affects air quality and climate, remains poorly understood.

About half of present-day cloud condensation nuclei originate from atmospheric nucleation, frequently appearing as a burst of new particles near midday. Atmospheric observations show that the growth rate of new particles often accelerates when the diameter of the particles is between one and ten nanometres. In this critical size range, new particles are most likely to be lost by coagulation with pre-existing particles, thereby failing to form new cloud condensation nuclei that are typically 50 to 100 nanometres across.

Atmospheric aerosols and their effect on clouds are thought to be important for anthropogenic radiative forcing of the climate, yet remain poorly understood. Globally, around half of cloud condensation nuclei originate from nucleation of atmospheric vapours. It is thought that sulfuric acid is essential to initiate most particle formation in the atmosphere, and that ions have a relatively minor role. Some laboratory studies, however, have reported organic particle formation without the intentional addition of sulfuric acid, although contamination could not be excluded.

New guidelines for the surgical treatment of type 2 diabetes bolster hopes of finding a cure, writes Francesco Rubino, but long-standing preconceptions must be put aside.

What are we to do about antibiotic resistance? Last week, another government report repeated stark warnings about the crisis, and offered some suggestions to improve the situation. The UK report, prepared by a panel chaired by the economist Jim O'Neill, naturally focused on financial incentives, including US$1-billion prizes for pharmaceutical firms that develop new antimicrobial drugs.

Original Source

The stability of the East Antarctic Ice Sheet and its contribution to past sea-level rise are not well defined; in this paper, airborne geophysical data and ice-sheet models are used to show that the Totten Glacier has undergone large-scale retreats and advances, and that it could contribute several metres of sea-level rise in a fully retreated scenario.

A reconstruction of atmospheric CO2 concentration from boron isotopes recorded in planktonic foraminifera examines climate–carbon interactions over the past tens of millions of years and confirms a strong linkage between climate and atmospheric CO2.