Life in the gut: microbial responses to stress in the gastrointestinal tract.
The complex physical and chemical conditions encountered in the gut present a range of physiological challenges to both the commensal microbiota and to pathogenic microorganisms attempting to colonise the gut. The innate immune system of the host, the host's diet and the microbial population present in the gut all contribute to the chemical complexity of the environment. The huge population of microorganisms in the gut also has a significant impact on the physicochemical properties of the gut environment. By focussing on some of the key physical and chemical stresses encountered by microorganisms in the gut, some of the molecular responses are described. Some promising new experimental approaches are outlined for studying the behaviour of microorganisms and theirSouth Korea's vice foreign minister issued an urgent plea about the threat from Pyongyang, warning the United Nations Security Council that North Korea was “in the final stages of nuclear weaponization”.

“It will fundamentally alter the security landscape in the region and beyond” if the North is able to equip a missile with a nuclear warhead, Cho Hyun warned.

In the past few months, North Korea has rattled the world with a series of weapons tests. It detonated a hydrogen bomb and has launched multiple ballistic missiles, saying after the latest firing that it now has the capability to attack the US mainland and had devised a missile capable of carrying “super-large heavy nuclear warhead”.

The late-November launch soared higher than any previous test, US Secretary of Defence James Mattis said,