Shot of Science: Microbiome, Bees, Kgs, Molecules & Babies

What’s a kilogram?

We’d like fewer on our waistline but, at the greengrocer’s we want more (and for less money). If they’re gold, they cost tens of thousands of euros (each). They’re the first thing mentioned about a new baby. But what’s a kilogram?

It’s the only unit in the SI (International System of Units) which is still based on a physical object: a cylinder of platinum and iridium closely guarded in a high-security vault at Sèvres, near Paris.

The quest for a reliably constant (objects lose and gain atoms all the time and can potentially be stolen or destroyed) and worldwide accessible definition of the unit of mass dates back to the 1970s.  But only in the last year have scientists come close to a reaching a definition based on mathematical constants rather than a physical object.

The new definition would be in terms of Planck’s constant, which relates a particle’s energy to its frequency and – through E=mc^² – to its mass. They now have until the 1^st of July of 2017 to fix the exact value of the Plank’s constant (they must get three independent measurements to agree, using at least two different methods) and, all being well, in 2018 the venerable platinum-iridium cylinder (‘Le Grand K’) will finally be granted – after 126 years of tireless work – a well-earned  retirement. 

Birth-cohort study cancelled

An ambitious and far-reaching birth-cohort study has been cancelled only eight months into its life. The Life Study project, which aimed to find associations between factors early in life (such as maternal diet or economic status during pregnancy) and outcomes later in life (disease, cognition, earnings, etc.), was planning to collect information on 80,000 British babies throughout their lives.

The cancellation comes as a result of an extremely disappointing recruitment rate. Of the 16,000 expectant mothers the researchers were hoping to recruit by July 2016, only 249 had materialised from January until September. Falling participation rates are plaguing many other surveys and population studies (less than one year ago a similar study in the US was also cancelled), leaving scientists to wonder about the future of these useful studies. If the reason for their dwindling recruitment rates is people’s increasingly busy lifestyle, one alternative would be that of using the abundant data on people’s health, educational and income which can be found in many national databases. But – and we are back in a full circle – only with the consent of those concerned.

Wonderful gut

With ten times as many bacterial cells as human cells in our body, it’s not surprising that we seem to be obsessed with our microbial lodgers, judging by the number of scientific papers published on the topic every week. Scientists are studying links between our gut-dwelling bacteria and just about anything under the sun. The latest news are that our gut dwellers protects us from muscle wasting during intestinal inflammation and infection by harmful bacteria and that they influence our behaviour and brain development.

Our fascination with microbial lodgers is not confined to the ones inhabiting our bodies: among the recently published articles is one on the nasopharyngeal microbiome of cattle and its importance for the bovines’ health.

If these little darlings are the good guys, the baddies are definitely the antibiotics and scientists are busy studying the effects of antibiotics usage on our microscopic friends (and, as a consequence, our health). Scouring through the health records of around 150,000 children aged 3 to 18 from Jan. 2001 to Feb. 2012, they found that children who had taken more antibiotics had put on more weight by the time they were 15 years old, which was not surprising, as a similar effect has already been confirmed on animals, hence their use in animal feeds.

Even if, one day, the hype around gut microbiota turned out to be unfounded, if it’ll have helped curb our irresponsible use of antibiotics, we (and our microbial guests) will have gained better health all the same.

[5]radialene, the molecule that shouldn’t exist

It took two years and the help of a supercomputer but these chemists have succeeded: they’ve created [5] radialene.  The ring-shaped molecule, which is 10,000 times more reactive than others in the same family, – themselves very reactive: [6]radialene spontaneously combusts in air –  was considered too unstable to ever exist.

To create something that should not possibly exist, scientists also have to be very…well… creative (of course): instead of preparing the molecule in a pure state, they made it as a crystalline metal complex, using the metal to shield the molecule from reaction.

The reason for our interest in [5]radialene is not just its powerful reactivity. The hydrocarbon contains a ring similar to that of other chemicals which are widely used in the chemical industry (a sector worth nearly $1 trillion worldwide) to manufacture anything from cosmetics to drugs.  The discovery, then, could possibly lead to better ways to synthesise drugs. If our chemistry heroes can manage to tame this little beast…

Plants cheat bees with caffeine

Caffeine has long been considered a plant’s chemical weapon against herbivores. Now a team of scientists has discovered that plants use caffeine also to cheat their pollinators.

Intrigued by the presence of caffeine in plants’ nectar, which is not an herbivore’s forage, scientists have conducted field studies and discovered that the caffeine in nectar tricks the bees into perceiving a higher content of sugar. The bees foraging on caffeine-laced nectar returned to the same plant more often than the bees feeding on caffeine-free nectar. Perhaps it’s time to start calling cheaterbugs ‘cheaterplant’ instead.