17 April 2018: Dinosaurs Ended, And Started, With a Bang

In the news today: the dinosaurs in the UK government struggle with the notion of decency, and the dinosaurs in the American government struggle with the notion of honesty.

Which is why it’s best to turn off the radio, put down the newspaper, log off the computer and give the phone to the dog to play with for a while. Here’s a science story about actual dinosaurs.

Before they were wiped out by a meteor, Dinosaurs ruled the earth for over a hundred and fifty million years,. The footprints they left behind show that their ecological dominance across the world may also have been due to a major extinction event.

During the Jurassic and Cretaceous periods, dinosaurs flourished across every continent on earth, from enormous herbivores, to ferocious raptors, to tiny bird-like therapods. And while the catastrophic cau se of their demise is widely accepted, exactly how dinosaurs became so dominant, comprising over 90% of the fauna in some regions, has been unclear.

In a study published in Nature Communications this week, researchers from the University of Bristol in the UK and the Universities of Padova and Ferrara in Italy believe they have found the answer in the footprints dinosaurs left behind.

The researchers examined dinosaur footprints in rock strata in the Dolomites, a mountain range in Northern Italy. In rocks dated to be over 200 million years old, they found only a small number and diversity of footprints, showing that dinosaurs existed at that time in the early Triassic, but comprised less than 5% of the fauna.

Following a succession of rock strata, the scientists then found evidence for a period of dramatic climate upheaval known as the Carnian Pluvial Episode, or CPE, around 230 million years ago. During the CPE the climate shifted from arid to humid and back again several times in just a million years or so, and a large number of the world’s animal species became extinct as a result.

In the rocks dated after this period, the researchers found a sudden explosion of dinosaur footprints or all shapes and sizes. They conclude that the CPE extinction event left behind a wide array of ecological niches that dinosaurs quickly exploited, spreading and diversifying to become the dominant animals across the globe.

The results agree with evidence from dinosaur fossils in Argentina and Brazil, which show an explosion in diversity around the same period.

These findings show that the age of the dinosaurs may have started and ended with a bang.

Original Paper: https://www.nature.com/articles/s41467-018-03996-1

16 April 2018: Bacteria Beaten by Graphene Blades

The US, France and the UK have bombed Syria. UK PM Teresa May says it was all legal and morally sound. It’s legally questionable, and Macron says he convinced Trump to do it. It’s morally dubious, and sacked FBI director James Comey says Trump is morally unfit to lead anyway. 

So, you know, sounds legit.
[Sigh.]

Look, turn off the news about dubious airstrikes, here’s a happier story about warfare, this time on a microscopic scale in the medical battle against surgical infections. 

Material science researchers in Sweden have used Graphene, the world’s thinnest substance, to fight bacterial infections in surgical implants, such as hip and knee replacements. The material’s antibacterial effect isn’t because it’s acting as a drug: the researchers created a layer of tiny graphene blades to slice open and destroy invading bacteria.

When bacteria infect a surgical implant, they first form a skin at the surface of the implant known as a biofilm. In a paper published in the journal Advanced Materials Interfaces this week, researchers from Chalmers University of Technology in Sweden reported that a layer of tiny graphene spikes at the implant surface stopped the formation of a biofilm by slice through the invading bacterial cells’ outer membranes. 

Graphene is a form of carbon in which the atoms join together into a two-dimensional sheet, just one atom thick. Sheets of graphene have a suite of unique electrical and structural properties; in this case, however, the antibacterial value of graphene comes from its single-atom width: layers of graphene are the sharpest blades ever created.

The material scientists used a method known as plasma-enhanced chemical vapour deposition to grow a layer of tiny graphene spikes about 100 nm high — long enough to be deadly to tiny bacteria cells, but harmless to the much larger human cells. 

Importantly, the bacteria did not seem to develop resistance to the graphene blades over time. Because the graphene is only used locally at the site of the surgical implant, it has no broader impact on the vital friendly bacteria throughout the body.

Thin layers of Graphene have been trialled before as a barrier against surgical infections, with mixed results. The Chalmers team realised that the key to graphene’s potency is the angle of the flakes: when the graphene layers grow parallel to the surface or at a low angle, bacteria can easily attach and infect the site. 

But when the graphene is deposited as flakes perpendicular to the surface, the array of atom-thick knives easily slices through any bacteria cells that come too close.

12 April 2018: Frogs Bouncing Back with Surprising Secretions

The Americans are basically now playing a game of chicken with Russia over Syria, the UK is hacking ISIS, and China wins the prize for World’s Top Executioner. Important stuff, but for your own sanity, take a break from the news for a few minutes for some positivity from the science desk.

Frog populations have been in decline for decades around the world, in many cases from to an epidemic of the deadly amphibian chytrid fungus. Some Central American frog populations are bouncing back in an unexpected way: they appear to be developing better skin resistance to the fungus pathogen.

The finding should assist frog conservation programs against future disease outbreaks, and could even aid the fights against some human diseases.

Associate Professor Louise Rollins-Smith at Vanderbilt University and her international team of researchers tracked the deadly fungus as it spread across central America from Costa Rica through Panama over ten years, to test the strength of the fungus’s pathogens over time. 

Frogs defend against the fungal disease by secreting chemicals through their skin. The researchers measured the effectiveness of this defence response in areas where the fungus was established, in recently invaded areas, and in regions free of the disease. 

The finding that some frog species were winning the battle against the fungus was a welcome discovery, but also surprising.

The scientists expected the frog populations to be recovering because the fungus was becoming less toxic. Instead, they found that the frogs themselves were the cause: where the disease was established, the frogs’ skin secretions were more effective against the fungus, compared with secretions from frogs in unaffected regions.

It isn’t clear yet whether this is because the frogs that survive the disease already had stronger defences, or if the frogs were chasing their secretions in response to the infection.

Understanding how these frog populations have adapted to the fungal epidemic can aid researchers in dealing with future disease outbreaks and assist conservation efforts. 

The research may also provide new pathways for understanding and treating human diseases. Past research by Professor Rollins-Smith’s team identified frog skin secretions could be effective against some human pathogens, such as HIV and gonorrhoea.

Source: https://www.eurekalert.org/pub_releases/2018-04/vumc-srd041118.php

Original Paper: http://science.sciencemag.org/content/359/6383/1517

11 April 2018: Breaking Quantum Records

When the US and Russia are backing up their twitter feud over Syria with actual missiles, and the head of the International Monetary Fund describes the outlook for global trade with the words “Dark” and “Clouds”, clearly this is a day to fold up the newspaper and leave it on the park bench for someone else to angst over.

Instead, here’s a cheery news story from the science desk:

A team of physicists in Germany and Austria have set a new record for quantum entanglement, using a laser ion trap to create a system of twenty caesium atoms in a single, entangled quantum state. The result brings the tantalising promise of novel technologies such as quantum computing closer to reality.

The previous entanglement record, held since 2011 by members of the same research team, was 14 atoms. The new record required innovative experimental and theoretical advances, and the researchers are confident they can set much higher quantum records in the future.

The research group, led by Ben Lanyon and Rainer Blatt at the Institute of Quantum Optics and Quantum Information of the Austrian Academy of Sciences, with colleagues from the University of Ulm and the Institute of Quantum Optics and Quantum Information in Vienna, published their record-breaking results in Physical Review X this week.

Quantum entanglement is a mysterious but critical concept in the very modern technologies of quantum information and quantum computing. Particles in an entangled state lose their individuality; instead, their behaviour can only be described as a whole system, even when the entangled particles are separated by very large distances.

The idea goes back more than eighty years to a famous paper by Einstein, Podolsky and Rosen, and was a subject of theoretical debate for decades. In recent years, with advances in both theory and experimental ability to trap and control atoms, quantum entanglement has become a very hot field.

Entanglement leads to strange and often counter-intuitive applications, such as quantum teleportation, where information can be instantly sent from one location to another, and quantum computing, which uses entangled quantum bits, or qubits, to solve problems beyond the capability of a conventional computer.

These applications are constrained by the difficulty in producing and measuring quantum effects in systems larger than just a few atoms. Intrusions from the surrounding environment, such as heat, quickly wipes out the connections between the entangled particles, a process known as quantum decoherence.

The great challenge physicists face is creating systems with a sufficient number of entangled particles or atoms, and maintaining the systems for sufficiently long periods of time. Using laser light to trap and control twenty caesium atoms, Lanyon and Blatt’s team were able to entangle pairs of atoms, and then use novel theoretical and experimental methods to detect the spread of entanglement effects across the remainder of the system.

They have set an ambitious goal of producing an entanglement of fifty atoms. A fifty-quit quantum computer would allow physicists to solve certain classes of problems that would cause the most powerful supercomputers on the planet to choke.

Original Source: https://www.alphagalileo.org/en-gb/Item-Display/ItemId/162049

Research paper: https://journals.aps.org/prx/abstract/10.1103/PhysRevX.8.021012

10 April 2018: Choose Your Vape Wisely

In the news today, Zuckerberg says he’s sorry that Facebook is such a cesspit, Bill Cosby’s back in court ... and speaking of sexual assaulters, is it bad news for a President when his personal lawyer is raided by the FBI?

Never mind. Close your browser tabs, put on your vintage smoking jacket and fire up your battery powered cigarette substitute of choice and have a listen to a science story instead — but choose your liquidised flavour wisely.

The huge popularity of e-cigarettes has produced an explosion in the number of flavoured liquids available to consumers, from menthol to rhubarb and custard. New research shows that the ingredients used to create many of these flavours increase the production of chemicals called free radicals, which are linked to cancer and other diseases. 

Inhaling e-cigarette vapour, or just vaping, has been hailed as a harmless alternative to smoking — after all, users are just breathing in flavoured water vapour, and the flavours have been tested and approved as safe by the appropriate authorities. 

Research published this week in the Journal Free Radical Biology and Medicine by scientists at Penn State College of Medicine shows there is a flaw in this approval process: the chemicals are not tested when heated, which is what happens inside an electronic cigarette. Heating can change the chemistry taking place inside the liquid, producing different amounts of free radicals.

The researchers measured the levels of free radicals produced by 50 flavours of e-cigarette liquids, and found that almost half of them increase the amount of free radicals compared with unflavoured liquid. They also identified a few flavours that reduced free radical levels.

The research team used these results to isolat six specific flavour ingredients that produce significantly higher levels of free radicals, and one that almost halved free radical production. 

The findings suggest that e-liquid flavours could be carefully designed to minimise health risks. With vaping rapidly increasing in popularity across the world, and with many flavours like bubblegum and sherbet clearly marketed to children, this research provides important data to help authorities understand the risks of vaping and regulate potentially harmful e-liquids.

Source: https://www.eurekalert.org/pub_releases/2018-04/ps-tpb040918.php

Original Paper: Free Radical Biology and Medicine, Volume 120, 20 May 2018, Pages 72-79 https://www.sciencedirect.com/science/article/pii/S0891584918301230?via%3Dihub

6 April 2018: Vampire Bats!

Vampire bats are infamous blood suckers, and they are the only mammals on earth that feed exclusively on blood. It’s a peculiar diet, very low in carbs and high in protein, and biologists have long puzzled over just how these little chiroptera evolved to live on such an unbalanced diet.

Research published in Nature Ecology and Evolution this week showed that to understand the bats, you have to understand their gut microbes as well: to survive on their meagre diet the vampire bats evolved in tandem with their internal microorganisms.

Led by Professor Tom Gilbert at the Centre for GeoGenetics at the University of Copenhagen, the international team of biologists showed that, to understand how a species adapts to its environment, it’s vital to consider both the genetics of the species itself, and of the organisms that live in symbiosis with it — collectively known as the hologenome. 

Blood is around 80% water. Of the rest, most is protein, and a fraction of a percent is carbohydrate. Most animals would not survive on blood alone, but vampire bats have evolved specialised immune systems to deal with blood-borne diseases, and kidneys able to manage the high protein levels.

The researchers knew, however, that this wasn’t enough. They demonstrated that vampire bats became blood-suckers through close co-evolution with their own gut microbes.

By examining the bats’ hologenome, including the genetic code of the bats and their gut microbes, the researchers identified that the bats and microbes evolved together to live on blood. The microbes have adapted to help the bats get rid of waste, and compensate for the lack of dietary carbs and fats.

Vampire bats are an excellent species for this research because of their extreme diet, but the researchers state that the results are broadly applicable: to understand the animal, you have to understand its hologneome.

Original Paper: Nature Ecology & Evolution (2018) doi:10.1038/s41559-018-0476-8

Source: www.alphagalileo.org/ViewItem.aspx?ItemId=185088&CultureCode=en

5 April 2018: Draining the Swamp is No Laughing Matter

Drained swamps and wetlands across the world are bubbling with laughing gas, and it’s no joke: nitrous oxide, or N2O, is a potent ozone depleting gas and contributor to global warming. Nitrogen-rich fertilisers and the destruction of peatland for agricultural use are to blame.

A team of geographers led by Professor Ülo Mander at the University of Tartu in Estonia studied gas emissions from peatlands around the world, to build the first global database of N2O emission from organic soils. 

They published their findings in the journals Nature Communications and Scientific Reports this week, calling for the protection of existing peatlands, re-wetting of drained marshes and bogs, and the avoidance of nitrogen-rich fertilisers.

Nitrous Oxide, also known as laughing gas, is used in dentistry and surgery as an anaesthetic and analgesic. But N2O in the atmosphere is no laughing matter: it’s one of the most potent greenhouse gases, trapping around three hundred times more heat than CO2. It is also the most significant contributor to ozone depletion.

Peatlands doesn’t typically release N2O unless the water is drained or the soil turned over, according to the study. The researchers discovered that, clearing wetlands for crops, grazing or development triggers microbial processes that release significant quantities of Nitrous Oxide.

The effect is particularly strong where the soils are nitrogen rich due to past grazing, or from floodwaters carrying nitrates from fertilised land.

Original paper: www.nature.com/articles/s41467-018-03540-1
Source: www.eurekalert.org/pub_releases/2018-04/erc-asb040418.php

4 April 2018: Burning Wood in Norway

Today's news brings epic eye-rolling over gender pay gap excuses, Trump’s wall built from the flesh of military personnel, and Russia and Facebook vying for the world’s least-trusted institution.

Instead, ignore the front page and curl up in front of a warm fire while we consider the science of burning wood in Norway, published in the journal Scientific Reports recently. But don’t get too comfy there — this toasty-warm, carbon-neutral energy source may not be quite so climate-friendly after all.

The Norwegians have raised the chopping, stacking and burning of wood to an art form — they even make epic 12-hour TV shows about it. Statistics Norway estimates over a million households burned more than a million tonnes of wood in 2016.

Because the wood is sourced mostly from plantation forests, it’s considered to be a carbon-neutral energy source: the carbon released as the wood burns are absorbed by the next generation of growing trees. CO2 released from burning biomass aren’t even counted in measures of carbon emissions.

Not so fast, say a collaboration of researchers from the Norwegian University of Science and Technology, the Norwegian Institute of Bioeconomy Research, the Norwegian University of Life Sciences and SINTEF Energy. While the cycle of biofuel carbon emission and re-absorption is broadly true, the full impact of burning so much wood on the climate is a bit more complex, and may in fact be warming the planet a lot more than previously thought.

First, there’s the issue of logging. Cutting down and chopping up so many trees requires loads of machinery, which emits a lot of carbon. Then again, the warming caused by those emissions is offset by the cooling effect of the large, snow-covered areas uncovered by logging, which reflect sunlight back into space.

The researchers also measured many different kinds of carbon emissions coming out of Norway’s many chimneys, including soot, also known as black carbon, which has a double impact on climate. Not only does soot itself increase warming in the atmosphere, it settles on snowy ground and reduces reflectivity, decreasing the snow’s cooling effect.

Soot emissions have halved in the last few decades thanks to modern, efficient wood-burning stove technologies. But the size of the soot particles is an important factor in their warming effect, and the tiniest, nano-sized particles are the most challenging to filter out.

So while it’s not necessary to brick up the fireplace, lock away the axe, and binge-watch your scandi-noir dramas under a duvet, this research shows just how tricky it is to be Hygge and carbon neutral at the same time.

Original Paper: Scientific Reports volume 8, Article number: 3299 (2018)

Find it at: www.nature.com/articles/s41598-018-21559-8