Last year it was reported that there could soon be up to 123 boys aged 16 to 17 for every 100 girls the same age in Sweden. This disparity was thought to be caused by an influx of teenage boys claiming asylum in the country. We look at whether age testing of asylum seekers has had an impact and skewed the sex ratio in Sweden.

China's Livestreaming: The Super Fan: BBC Trending brings you the second half of a strange love story involving one of China's most well-known live streamers, and a fan who pays to watch her live stream every single day. Last week we introduced you to Lele Tao, a well-known live streamer in China. This week we meet Shage, who is a devoted fan of Lele's and witness their first ever face-to-face interaction.

Every country in the world has at least one Sign Language. Each is a complete communication system with its own grammar, lexicon and structure and has evolved over centuries, just like their verbal counterparts. Although many have legal status under disability legislation, only four have been given the status of a recognised official language. But not everyone who is deaf uses sign language, and not everyone who uses sign language is deaf. Some deaf rights campaigners say that Sign language is a signifier of belonging to a Deaf community, with a rich cultural legacy. But does the choice to use hearing aids and cochlear implants to help use verbal language really mean a rejection of deaf culture and a deaf identity?

(image: teenagers enjoying themselves outdoors. Credit: Shutterstock)

The only woman to win the maths world’s biggest prize has died at the age of 40. As the only female winner of the Fields Medal – the maths equivalent to the Nobel Prize – Iranian mathematician Maryam Mirzakhani inspired a generation of female mathematicians. We look at her life and her legacy.

The first of two special reports reveals a unique Chinese love story involving one of China's most well-known live streamers, and a fan who watches her on a screen every single day. Live streaming is big business in China, with half of the online Chinese community using livestreaming apps in 2016.

And why do some people crave the limelight? Jordan Dunbar undergoes an experiment to find out what the limelight does to our bodies, to get a chemical answer.

(Photo: Front pages of Iranian newspapers on 16 July 2017, bearing portraits of the top female mathematician Maryam Mirzakhani. Credit: Atta Kenare/Getty Images)

We discover how every shot at the Wimbledon tennis championships is counted, analysed and makes its way to our phones, desktops and TV screens. How useful is this information for players and their coaches? The statistics prove and disprove some of the received wisdom of the game.

New Chinese regulations have resulted in a crackdown on online videos. Chinese censors have banned around 84 categories of material including prostitution, drug addiction, and extra marital affairs, and the classification of homosexuality as an 'abnormal' sexual activity has caused anger online.

What drives women – and men – to choose to be childless, especially as they often face suspicion, abuse even, for being selfish or materialistic. Women, in particular, who decide not to have children can experience the full force of this near-universal stigma. Mary-Ann Ochota reports.

(image: Venus Williams plays a backhand during the Ladies Singles at Wimbledon. Credit: Getty Images)

The American basketballer Stephen Curry has just signed the biggest contract in NBA history for $200 million over 5 years but amazingly, according to fellow superstar player Lebron James, he’s probably being underpaid. We look at the economics of superstar sports salaries.

Rumours in football and the fake news generated by these rumours are nothing new, but we’ll be looking at the way these stories impact clubs, players and fans.

And what’s in a kiss? Charlotte McDonald examines the biochemistry, psychology, anthropology and history of kissing. Where does it come from and is it innately human?

(Image: NBA Finals: Game Four, Credit: Ronald Martinez/Getty Images)

UEFA, European football's governing body, is currently trialling a new system for penalty shoot-outs that is based on mathematical research. Currently 60% of penalty shoot-outs are won by the team going first, so can this unfairness be overcome?

The death of a teenager in India at the hands of a mob led to an online campaign, which within days sparked a trending hashtag and worldwide street protests. We pick apart the #NotInMyName campaign.

And when many people struggle to maintain one relationship, why do some people enter into multiple simultaneous marriages? Lucy Ash speaks to polygamists around the world to find out why they were drawn to these complex relationships and what impact they have on the people involved.

(Photo: Various numbers. Credit: Shutterstock)

Grenfell Tower, a residential block in London, made headlines around the world when at least 79 people died there in a fire while many are still missing. But how unusual are such lethal fires? Are tower blocks really dangerous? Or are they safer than houses?

We investigate some of the fake victim images which appear online in the wake of deadly attacks and disasters. Who are the victims and perpetrators, and why are these images circulated?

Why do foreign migrants yearn to go home and what happens when they do? Some have had no choice, but others are influenced by nostalgia for their early lives. When they go back, can the old country live up to their hopes and dreams? Shivaani Kohok hears emotional tales from those returning to Jamaica, Sierra Leone, India and Ghana.

(Photo: Smoke rises from the 24 story Grenfell Tower in West London. Photo: Leon Neal/Getty images)

The results of the UK general election are in – but what do they mean? Did more young people vote than expected? How many extra votes would the Labour leader Jeremy Corbyn have needed to become Prime Minister? Would planned boundary changes have made a difference? Tim Harford and team give the latest analysis.

(Photo: young voters arriving at a polling station in Glasgow to vote in the General Election. Credit Andy Buchanan/Getty Images)

Cheick Tiote, the much loved former Newcastle United player collapsed and died while training with Chinese side Beijing Enterprises earlier this month. His death and that of other black footballers have caused some commentators to ask if cardiac arrest – one of the most common causes of death on the field – is a greater risk factor for people of African heritage.

The conflict in Venezuela has now moved beyond the country’s borders – both on and offline. It involves Venezuelan exiles publicly shaming people living abroad who are connected to the government. We hear from those who are targeted and targeting.

(Photo: Cheick Tiote of Newcastle United in action during the Barclays Premier League match between Newcastle United and Southampton at St James Park Credit: Getty Images)

Can medical statistics be transformed into music? That was the challenge set by epidemiologist Elizabeth Pisani for composer Tony Haynes. The result was Song of Contagion to be performed this month by his Grand Union Orchestra with steel pans, saxophones and singers telling the story of diseases including Zika and AIDs.

What Is 4Chan? How an anonymous social network spawned some of the biggest and most recognisable online political movements. We look at the origins, the people who use it and where it’s going.

And why do we talk to ourselves? Matthew Sweet hears how it can calm us down, help us organise our thoughts, and in the case of Sarah Outen, who spent four and a half years rowing, cycling and kayaking around the planet, he hears how it saved her life on more than one occasion.

(Photo: Detail close up of French Horn musical instrument, part of the Brass family of instruments. Credit: Shutterstock)

Our entire education system is faulty, some experts claim, as it fails to prepare children for a future world of work in which 65 % of jobs have not yet been invented. We set off on a round-the-world sleuthing trip to trace this statistic that has been causing headaches for students, teachers and politicians alike.

Travelling without male consent: we unpick the case of Dina Ali, the 24-year-old Saudi national whose story triggered a viral hashtag challenging Saudi Arabia’s 'guardianship' rules, which give male guardians control over women. Where is Dina now? And why was the hashtag she inspired so significant?

Dotun Adebayo talks to people whose daily life can include verbal and even physical abuse. They include an 18 year old referee in Manchester and electricity workers in Lagos in Nigeria who are regularly beaten up as they disconnect disgruntled customers. And the plus side of doing a thankless job from a debt collector in Jamaica and death row lawyers in Trinidad and Tobago and Guyana.

(Photo: Classmates taking part in peer learning. Credit: Shutterstock)