This article is a preview from the Autumn 2017 edition of New Humanist.

Physics – Ceri Brenner

Imagine a world where we don’t need to burn fossil fuels for electricity. Where the only waste product is helium, and half of the fuel can be extracted from seawater. Imagine the solution is to generate a miniature star, store it in a special magnetic bottle and use its burning output to replace the heat source of burning coal and gas. Physicists have been working on this creative vision of clean energy for all since the 1960s. The process is called fusion and it is the binding of two isotopes of hydrogen to form helium. This process releases energy by transforming mass – that sits still and does nothing – into movement energy which can be transformed into heat and used for electricity generation. An elegant demonstration of Einstein’s E = mc2 in action.

The quest for fusion is vital but horribly difficult. The centre of the Sun is a colossal 15 million degrees Celsius. We need to heat our blob of star power to more than 70 million degrees Celsius. There’s no material known that can withstand that temperature, so one way to contain the burning fuel is to use a magnetic structure that confines the blob away from direct contact with the container walls. And this works. Experiments all over the world have been demonstrating the fusion process for decades. The hurdle now is releasing more energy than you put in to get it going. That’s the point at which you have a design that can be used for commercial-scale electricity generation.

One of the many stumbling blocks is that energy is lost at the edges of the burning blob by it cooling down and causing a drop in the rate of the fusion process. However, a team of US fusion physicists have recently published results in Physical Review Letters showing that if the walls are coated with lithium then the temperature stays the same from the centre to the edge. Bingo! The lithium acts a barrier between the burning fuel and the walls by capturing any stray escaping fusion particles. This means that the wall is not subject to a particle bombardment that would otherwise spit out cold particles into the fuel. A lithe solution for star power.

Ceri Brenner is a physicist who works for the Science and Technology Facilities Council

Chemistry – Mark Lorch

As you daub yourself with antiperspirant of a morning, have you ever pondered what you are applying to your armpits? And if so, have you wondered how it keeps your underarms dry?

The first question is pretty easy to deal with. Ever since 1903 (when Everdry was launched in the US) the active ingredient in antiperspirants has invariably been aluminum salts. Other ingredients may kill sweat-eating bacteria and mask their unpleasant smells, but it’s the aluminum salts that stop the sweat. It has generally been thought that once applied, the salts react with water to form a gel of aluminum hydroxide, and this then plugs up your pores and seals in the sweat.

However, things aren’t actually that simple. A team from L’Oreal delved into the microscopic workings of the perspiration process by building a tiny, 50-micrometer, T-shaped model of a sweat duct. Antiperspirant was applied to the top of the T on the model, and sweat (harvested from the armpits of volunteers after a session in the sauna) was pumped through it. The researchers then observed how the artificial pore clogged up. First, proteins from the sweat mix with the aluminum salts to form a membrane around the walls of the pore, and then the membrane collects more proteins from the flowing sweat, slowly blocking up the channel. All this was confirmed by surprisingly detailed analysis of the pore-blocking plug.

The critical point here is that proteins are essential to the pore-forming process. Without them the aluminum salts flow right through the pore, without causing any blockage at all. Which means that your underarm roll-on or spray actually works in quite a different way than previously thought. This may seem rather trivial, but now that we know that reactions involving sweat proteins are a key to effective antiperspirants, it might be possible to improve the key ingredients of underarm roll-ons, which have remained unchanged since 1903. And when the worldwide market in antiperspirants is valued at almost $20 billion there is plenty of incentive to do just that.

Mark Lorch lectures in chemistry at Hull University

Biology – Lydia Leon

The free labour of bees maintains global biodiversity and contributes an estimated £650 million to the UK economy. But bees are declining at an alarming rate: 60 per cent of hives have been lost in the US since the 1940s. There is significant evidence that pesticides, specifically neonicotinoids (NNIs), have a role in bee population decline via effects on reproduction, productivity and honing abilities. NNIs are applied to seeds before sowing and spread systemically through the plant. Laboratory tests have been criticised for using unrealistic doses of the compounds. Some of this criticism is legitimate – but much originates from multi-million-dollar agro-chemical PR campaigns..

In 2013 the EU placed a temporary moratorium on the use of NNIs on flowering crops that attract bees, to give scientists time to investigate. The recommendations are expected in November. In June, the largest study to date conducted under real-world agricultural conditions was published in the journal Science. Ironically, the work was funded by two main NNI producers: Bayer and Syngenta. Perhaps unsurprisingly, the interpretation of the data by the scientists and commercial funders differed.

The publication describes the impact of seed sprays containing either NNIs or no NNIs across 33 sites in the UK, Hungary and Germany. The scientists concluded that, in line with the majority of previous research, exposure was harmful to bees. In sites where higher concentrations of NNIs were found, bee survival and productivity were worse. Interestingly, in Germany this negative impact was not observed. Whilst the commercial funders cited this as a limitation to the work, the researchers hypothesised that it could be due to the wider array of foods available to German bees, and the generally healthier state of the hives. These compelling yet at times inconsistent results show the difficulties of real-world research within complex ecological systems. Advocates of stricter control of NNIs have suggested this is the final nail in the coffin. Yet this is only the beginning of the fight to keep our bees alive

Lydia Leon is a research associate in women’s health at Kings College London and University College London