What new technologies are being developed to minimise the long-term storage of spent nuclear fuels?

Nuclear power is very clean and carbon neutral. But spent nuclear fuel has a storage lifetime of 300,000 years.

Reprocessing used nuclear fuel is currently carried out on large scale using the “Plutonium Uranium Reduction and Extraction” (PUREX) process. During this process, the fuel is reduced to 15% of its original weight and the extracted uranium and plutonium are used as “Mixed Oxide Fuel”. This has been carried out at scale by the UK at Sellafield (now curtailed) and continues in France at La Hague.

The residual high-level waste has a storage lifetime of 9,000 years. Much of the remainder of the long-term radiotoxicity of the residual waste is due to traces (0.1%of the original fuel) of the minor actinides. Separating these minor actinides from the chemically very similar lanthanides and other fission products is the next key step in the future reprocessing of spent nuclear fuel.

So, what’s the challenge? The actinides can be used as a fuel in the next generation of nuclear reactors and converted into benign products. But the accompanying lanthanides would “poison” the reactor, causing it to shut down.

In this recording of an online talk, Laurence Harwood reports on the important progress that has been made in the advanced reprocessing of spent nuclear fuel. The used fuel need not be a liability but a source of yet more power.

Whilst we can often successfully treat those that are diagnosed at an early stage, depending on the type of cancer, even the most effective treatments are often not effective when cancer is diagnosed at an advanced stage. For these reasons, great efforts are made to diagnose cancers as early as possible.

There is only so much that can be done to make the public and clinicians aware of the signs and symptoms. To make real progress, we need better tests and to use them in screening programs targeting seemingly healthy people.

Up until now, screening tests have been designed to look for one specific type of cancer at a time. And a significant problem is posed by the unreliability of these tests. For every early detection of cancer, several others receive a false-positive. If we were to have 20 different screening programs (one for each type of cancer), most people would receive a false-positive result once every few years. These false-positive tests cause anxiety, can lead to invasive further testing and are expensive to the NHS.

But there is hope on the horizon. Recent technological advances allow for the detection of tiny fragments of genetic material present in the blood. This, for the first time, offers the possibility of having a single blood test for many different types of cancer. One such test can detect 50 different types of cancer, with varying success, and it only very rarely gives a false positive result. If this test can find cancer early enough, it could revolutionize the way we approach cancer control.

Professor Peter Sasieni explains this ground-breaking development in cancer research.

Since its discovery in 1840, polar scientists have gone to great lengths to explore Antarctica’s depths. An ice-covered continent the size of the United States and Mexico combined, it has been the site and subject of revelatory scientific studies and awe-inspiring adventures. In its vastness and mysteriousness, it has captured imaginations and has been the source of inspiration for centuries.

The significance of Antarctica’s role in the maintenance of ideal life conditions across the entire planet has since been established. Its ice, ocean and ecosystem play a vital role in the regulation of the global climate. Although many questions remain about its past and its present, particular attention has been turned to the future of its ice sheet. Concerns about its diminishing size have been at the heart of the polarising climate change debate.

In this recording of an online event, Professor Helen Fricker speaks of the physical processes which determine the state of the ice, the transformational impact of satellite observation on her studies as well as the effects that the atmosphere and the oceans have on the ice.

As getting to grips with Antarctica involves a range of specialisms and extensive international collaboration, Helen goes beyond her background in geophysics to provide a comprehensive understanding of the continent. As one of an increasing number of women polar scientists, it’s a privilege to hear from someone who has first-hand experience of seeing the effects of climate change.

This online event was organised in collaboration with the Institute of Physics.

Find out more about the IoP here: https://www.iop.org

Multi-award-winning scientist Sir Paul Nurse considers the most fundamental question in biology, “What is Life?”

In a highly anticipated talk, Sir Paul seeks to answer this profound question by first exploring five great ideas in biology:

The cell – the fundamental unit of all living things

The gene – how do cells store, preserve and pass on information?

Evolution by natural selection – how is genetic information accurately transmitted to subsequent generations, whilst at the same time introducing sufficient variability for natural selection to operate and for new species to arise?

Life as chemistry – how do cells host myriad simultaneous chemical reactions in a minute space? What is the central role of carbon polymer chemistry?

Life as information – how do cells and organisms regulate and coordinate their internal environment? And how do they respond to stimuli and conditions in their external environment?

From consideration of these five fundamental concepts, Sir Paul then relates a number of principles which set a direction of travel towards a definition of life – something that requires more than just a description of what living things do.

His book “What is Life” has been published in 22 countries.