Hello. Here's your morning briefing:

Image copyright EPA

Trump's cognitive ability 'normal'

Donald Trump's White House doctor has said he has "no concern" about the US president's mental health, following questions raised in a recent book. Ronny Jackson said Mr Trump had undergone a three-hour examination and was in excellent overall condition. He added that the president had benefited from a lifetime of abstaining from tobacco and alcohol, but said the 71-year-old could do with more exercise and a lower-fat diet.

According to the book Fire and Fury, by journalist Michael Wolff, Mr Trump's staff see him as a "child" who needs "immediate gratification". But the president has described Mr Wolff's work as "full of lies". Here's the full medical report.

NHS 'haemorrhaging' nurses

One in 10 NHS nurses in England is leaving every year, figures provided to the BBC show. More than 33,000 walked away from the service last year, according to NHS Digital, a rise of 20% since 2012/13. Other parts of the UK are also experiencing problems retaining nurses, writes BBC health correspondent Nick Triggle. The regulator, NHS Improvement, is rolling out a programme to help reduce the number of leavers. One nurse, Mary, reveals her reasons for going.

Most new cars must be electric by 2030, ministers told

Three-fifths of new cars must be electric within the next 12 years if the government is going to reach its targets on greenhouse gas emissions, a report says. The Committee on Climate Change, which offers independent advice to ministers, also wants more energy-efficient homes to be built - and more trees to be planted to absorb carbon dioxide. The government says the UK is cutting greenhouse gas emissions faster than any other G7 nation and that its strategy "will continue to evolve".

Get news from the BBC in your inbox, each weekday morning

Drivers sleep in cars as snow blocks roads

Heavy snow in Scotland has forced hundreds of motorists to spend the night in their cars. Mountain rescue teams have helped people stuck on the M74 in Dumfries and Galloway, with several lorries having jack-knifed. The snow has also caused problems in Northern Ireland, where schools are closed and public transport is disrupted. More heavy snow showers are forecast in some parts of Scotland and Northern Ireland, while snow and ice are also expected in much of England and Wales.

'Superheroes don't work 90-hour weeks'

By Michael Cowan, Victoria Derbyshire programme

Staff at Normally Design in London work a four-day week but are paid as if they were doing the traditional five days. The days remain eight hours long. Designer Basil Safwat said the shorter weeks didn't mean cramming five days of work into four and he had only worked long hours a couple of times in two years. "There's a social encouragement to make sure you use that fifth day for yourself and not to do work. You're not going to get Brownie points for replying to emails on the fifth day."

Read the full article

What the papers say

The collapse of construction giant Carillion garners much coverage. The Financial Times says the firm was left with just £29m in cash, showing the extent of its "financial black hole". Metro says the development means thousands of companies could "go to the wall". Elsewhere, the i reports that doctors offered jobs at short-staffed UK hospitals are being prevented from taking them up by "immigration red tape". And the Daily Mail leads on the appointment of Tracey Crouch to deal with the "social epidemic" of personal isolation, calling her "minister for the lonely".

Daily digest

Actress's death Home and Away star Jessica Falkholt dies three weeks after car crash

'I survived gaslighting' Three readers share their stories of psychological abuse by partners

Bayeux Tapestry Famous record of 1066 and all that to come to the UK for the first time

33,000 calories Wild dolphins burn up lots of energy - but how many salmon portions does that equate to?

BBC Ideas Is individualism a good thing?

If you see one thing today

Image copyright Julius Nielsen

The shark that could live for hundreds of years

If you listen to one thing today

Herodotus: Father of history or lies?

If you read one thing today

When you can and can't eat carbohydrates

Lookahead

10:30 A large fragment of the Union Jack believed to have flown from HMS Victory during the Battle of Trafalgar is expected to reach up to £100,000 when it goes for auction at Sotheby's.

19:30 US Secretary of State Rex Tillerson gives a speech on his country's policy towards Syria at Stanford University, California.

On this day

1983 BBC Breakfast Time - UK television's first breakfast news programme - launches, hosted by Frank Bough and Selina Scott.

From elsewhere

The women who took on the mafia (New Yorker)

What happens to your body during Dry January? (Independent)

Who gave most to charity in 2017? (Daily Telegraph)

The emotional legacy of The Breakfast Club (The Atlantic)