Surgeons often have to deal with the consequences of violent attacks - becoming all too familiar with patterns of public violence, and peaks around weekends, alcohol-infused events and occasions that bring together groups with conflicting ideals.

Professor Jonathan Shepherd not only recognised the link between public violence and emergency hospital admissions, he actually did something about it.

As a senior lecturer in Oral and Maxillofacial Surgery in the early 1980s, Jonathan started looking into this trend - and his research revealed that most violent assaults resulting in emergency hospital treatment are not reported to police.

As a result, he devised the ‘Cardiff Model for Violence Prevention’: a programme where hospitals share data about admissions relating to violent attacks with local authorities. He also went on to study various aspects of violent assault and deliver evidence-based solutions - from alcohol restrictions in hotspots, to less breakable beer glasses in pubs.

The impacts have been significant, delivering reductions in hospital admissions and in violent attacks recorded by police; not only in Cardiff, but in cities around the world where the model is used. Today, as an Emeritus Professor of Oral and Maxillofacial Surgery at Cardiff University - where he’s also Director of their Crime, Security and Intelligence Innovation Institute - Jonathan continues to bring together the medical sector with local authorities, finding practical ways to make cities and their residents safer.

But his career, straddling the worlds of practise, science and policy, is an unusual one; here he talks to Professor Jim Al-Khalili about what drove him to make a difference.

Presentedby Jim Al-Khalili

Doyne Farmer is something of a rebel. Back in the seventies, when he was a student, he walked into a casino in Las Vegas, sat down at a roulette table and beat the house. To anyone watching the wheel spin and the ball clatter to its final resting place, his choice of number would’ve looked like a lucky guess. But knowing the physics of the game and armed with the world’s first wearable computer, which he’d designed, a seemingly random win was actually somewhat predictable.

Doyne is an American scientist and entrepreneur who pioneered many of the fields that define the scientific agenda of our time, from chaos theory and complex systems to wearable computing. He uses big data and evermore powerful computers to apply complex systems science to the economy, to better predict our future. Much like roulette, economics can appear random but, with the right tools and understanding, it is anything but.

Now Director of the Complexity Economics Programme at the Institute for New Economic Thinking at Oxford, Doyne says there’s a real need to act, to use these powers of prediction to help resolve one of the most pressing questions of our time - how best to prevent climate change.

Presented by Jim Al-Khalili

Elephants are the largest living land mammal and today our plant is home to three species: the African bush elephant, the African forest elephant, and the Asian elephant.

But a hundred thousand years ago, in the chilly depths of the Ice Age, multiple species of elephant roamed the earth: from dog-sized dwarf elephants to towering woolly mammoths.

These gentle giants' evolutionary story and its parallels with that of humankind has long fascinated Dr Tori Herridge, a senior lecturer in evolutionary biology at the University of Sheffield, where - as a seasoned science broadcaster - she's also responsible for their Masters course in Science Communication.

Tori has spent much of her life studying fossil elephants and the sites where they were excavated; trying to establish facts behind relics that are far beyond the reach of Radio Carbon Dating. To date she's discovered dwarf mammoths on Mediterranean islands, retraced the groundbreaking Greek expedition of a female palaeontologist in the early 1900s, and even held an ancient woolly mammoth’s liver. (Verdict: stinky.)

But as she tells Profesor Jim Al-Khalili, this passion for fossil-hunting is not just about understanding the past: this information is what will help us protect present-day elephants and the world around them for future generations.

Presented by Jim Al-Khalili

What does it take to earn the nickname, ‘The Leonardo da Vinci of heart surgery’?

That's the moniker given to today's guest - a man who pioneered high-profile and often controversial procedures, but also helped drive huge medical progress; carrying out around 2,000 heart transplants and 400 dual heart-lung transplants during his 60-year career.

Sir Magdi Yacoub is Emeritus Professor of Cardiothoracic Surgery at Imperial College London, and Director of Research at Harefield Hospital’s Magdi Yacoub Institute.

But it hasn't always been plain sailing. At times, his work – such as early, unsuccessful transplant attempts, or using a baboon as a life-support system for a baby – attracted serious public criticism.

Speaking to Professor Jim Al-Khalili, Sir Magdi reflects on the highs and lows of his cardio career, and offers his advice to the next generation of surgeons and researchers hoping to make their mark in heart medicine.

Presented by Jim Al-Khalili

What's it like living underwater for two weeks? What's the trickiest part of training to be an astronaut? What are the most memorable sights you see from space?

After a childhood packed with outdoor adventures, via the Cub Scouts and school Cadet Force, Tim joined the British Army Air Corps and became a military flying instructor then a test pilot; before eventually being selected as a European Space Agency (ESA) astronaut.

In 2015, Tim became the first British ESA astronaut to visit the International Space Station. Over the course of a six-month mission, he took part in more than 250 scientific experiments and worked with more than two million schoolchildren across Europe.

In a special New Year’s episode recorded in front of an audience at London’s Royal Society, Professor Jim Al-Khalili talks to Tim about his lifelong passion for adventure, the thrill of flight and why scientific experiments in space are so important.

Presented by Jim Al-Khalili

As the famous frog once said, it's not easy being green. And when it comes to decarbonising industry, indeed, reducing emissions of all sorts, the task is a complex one.

Fossil fuels are used to manufacture some of mankind’s most ubiquitous products, from plastics to cement to steel; and even in areas where we’re trying to improve our footprint, there are repercussions. Mining lithium for electric car batteries isn’t exactly without impact. Add to the mix stories of corporations prioritising profits, and governments focusing on short-term popular policies – and it would be easy to feel disheartened.

Professor Anna Korre says her role is to be the champion of science in this debate: providing clear evidence to help reduce environmental impacts, while allowing vital production processes to continue.

Anna is an environmental engineer at Imperial College London and Co-Director of the university’s Energy Futures Lab. Her work has led to a risk model that's now used in mining operations around the world – and her current research into sub-surface CO2 storage could hold the key to decarbonising British industry. But as she tells Jim Al-Khalili, social and familial expectations when she was growing up in her native Greece meant her succesful career in engineering very nearly didn't happen...

Presented by Jim Al-Khalili

Rosalie David is a pioneer in the study of ancient Egypt. In the early 1970s, she launched a unique project to study Egyptian mummified bodies using the techniques of modern medicine. Back then, the vast majority of Egyptologists regarded mummies as unimportant sources of information about life in ancient Egypt. Instead they focussed on interpreting hieroglyphic inscriptions, the written record in papyrus documents and archaeological remains and artefacts. Rosalie David proved that the traditionalists were quite wrong.

Professor David’s mummy research started at the Manchester Museum when she began to collaborate with radiologists at the nearby Manchester Royal Infirmary, taking the museum’s mummies for x-rays at the hospital. Her multi-disciplinary team later moved to a dedicated institute at the University of Manchester, the KNH Centre for Biomedical Egyptology. Over the decades, the team there has made remarkable discoveries about disease and medicine in ancient Egyptian society, providing a new perspective on the history of medicine and giving extraordinary insights into the lives of individuals all those years ago.

Rosalie tells Jim Al-Khalili about her journey from classics and ancient history to biomedicine, including some of her adventures in Egypt in the 1960s. She talks about some of her most significant research projects, and the 21st Century forensic detective work on the mummy of a young woman which revealed a gruesome murder 3,000 years ago...

Presented by Jim Al-Khalili

In the summer of 2003, Europe experienced its most intense heatwave on record - one that saw more than 70,000 people lose their lives.

That’s exactly what he went on to do - and, through this work and more, Peter has helped to shine a light on the causes and effects of climate change.

But the biggest challenge remains: Peter talks to Jim Al-Khalili about whether humanity can adapt quickly enough to deal with the increasingly dangerous effects of our warming world...

Presented by Jim Al-Khalili

Imagine a nanoparticle, less that a thousandth of the width of a human hair, that is so precise that it can carry a medicine to just where it’s needed in the body, improving the drug’s impact and reducing side effects.

Presented by JIm Al-Khalili

Darren Croft studies one of the ocean’s most charismatic and spectacular animals – the killer whale. Orca are probably best known for their predatory behaviour: ganging up to catch hapless seals or attack other whales. But for the last fifteen years, Darren Croft’s focus has been on a gentler aspect of killer whale existence: their family and reproductive lives .

Presented by Jim Al-Khalili