Sun cream vs multiple sclerosis

That multiple sclerosis (MS) is less common near the equator than it is in upper latitudes has led teams in recent years to explore this oddity and led one group to find that ultraviolet light (UV) suppresses the disease. Keen to take a closer look at this, a researchers applied sun cream to mice with the rodent version of MS just before exposing them to UV light. They fully expected the sun cream to block the protective effect of the light but this is not what happened. Instead, the cream granted further protection against the disease.

This surprising discovery led the researchers to run a follow up experiment with many sun creams. They found that not all were equal in their ability to suppress MS but that the few that did have a beneficial effect worked even when the mice were not exposed to UV light. Fascinated, the team broke the MS suppressing sun creams into their component parts and applied them one by one to the mice. You can read more in The Economist article that I wrote on this here.

Better training bomb sniffing dogs

Are we sure that box isn't tainted?

Image courtesy of US Navy.

One of the key arguments made for replacing bomb sniffing dogs with electronic noses is that the dogs are fallible and have the potential to be distracted by the presence of sausages whereas electronic noses are not. Yet defenders of the dogs argue that it is not so much that the dogs are making mistakes as they are being poorly taught by their handlers. Canines are currently judged during training and testing by how well they find intentionally hidden explosives. This method makes intuitive sense because handlers cannot see the odours themselves and certainly cannot smell them, so their intention is used as a surrogate for whether or not an odour is actually there. However, unintentional explosive odours can easily be presented and damage dog training. Now a team is revealing the invention of a vapour analysis device with real-time detection capabilities that will allow handlers to visualise the odours they are exposing to their dogs and vastly improve training.

The new technology has a detection library of nine explosives and explosive-related materials including some of the big baddies like nitroglycerin, triacetone triperoxide (used in the Brussels blasts) and cyclohexanone. It has detection limits in the parts-per-trillion to parts-per-quadrillion range and has the ability to reveal vapour plume dynamics. The team used the device as expert trainers were training and testing their dogs and the technology revealed that handlers were making mistakes during training. For example, in one test where the handlers believed they were presenting their dogs with 28 envelopes that were tainted with traces of the potent explosive RDX (trinitroperhydrotriazine) and 68 untainted controls, the researchers found that only 27 of the envelopes were actually tainted with the explosive and that six of the controls were carrying enough of the explosive residue to be detected by the dogs. This meant that on six occasions when dogs (correctly) identified the presence of the explosive on control envelopes they were treated as if they had made an error when they truly had not. You can read more in The Economist article that I wrote on this here.  

Origin of filter feeding in whales

Once sharp and pointy.

Image courtesy of NOAA.

Archaeopteryx played a pivotal part in revealing one of the greatest transitions in the history of life when dinosaurs took to the skies and fluttered away. There are not many transitions that can quite rival that evolutionary moment but, if there is one, it is the journey that the terrestrial ancestors of whales made into the sea. How the largest mammals on the planet came to lead the lives that they do today is a matter that is much shrouded in mystery. More specifically, how the blue whale and its kin ended up filtering tiny organisms out of the water with fibrous baleen when they started with sharp and pointed teeth is a subject of tremendous debate. Now a new fossil find is doing for baleen whales what Archaeopteryx did for birds by providing the first glimpse of an animal that was in the midst of a remarkable transition.

To say that the origins of baleen are controversial is an understatement. One hypothesis suggests that teeth were lost during a suction-feeding stage of whale evolution and that baleen evolved thereafter. The other suggests that baleen evolved before teeth were lost. The new fossil solidly supports the second argument. The new species, named Coronodon havensteini, dates to the Oligocene epoch roughly 30 million years ago and has an astonishing mouth. While most of its teeth indicate that it captured large prey, its broad lower molars frame narrow slots that look like that had to have been used for filter-feeding. This notion is further supported by the fact that, structurally, the rest of specimen looks like an ancient relative of the filter feeding branch of the whale family. Given this, the researchers are arguing that filter-feeding was preceded by predatory feeding, and that suction-feeding (which is seen in a few whales) evolved separately within a group that was removed from modern baleen whales. You can read more in The Economist article that I wrote on this here.

Antarctic monster

That antibiotic use fuels the rise of resistance in bacterial populations is well understood. What is less well understood is where the antibiotic resistant genes come from in the first place. Some have argued that modern antibiotic resistant traits have evolved when bacterial populations come under intense selective pressure from drugs. Others have argued that antibiotic resistant traits have always been present in wild bacterial populations and that as human use of drugs has increased this has driven the distribution of these traits to dramatically rise. Now the discovery of a worryingly resistant bacterium from Antarctica is providing strong support for the argument that resistant traits have always been around.

Antibiotic contamination in Antarctica is almost nothing. Yes, it is possible that a bacterium from a more antibiotic contaminated region of the world could migrate there through the sea, the rain or human activity but this is widely viewed as unlikely. It is for this reason that the discovery of an unstoppable bacterium on the frozen continent is so surprising.  

The species that has been found belongs to the genus Pseudomonas, the group that contains the highly troublesome Pseudomonas aeruginosa that routinely causes lethal resistant infections in nursing homes and hospitals. Yet, while P. aeruginosa is found all over the developed world and has had ample exposure to antibiotics over the years, the new species, creatively named 6A1, has never been seen by science before and appears to only occur in Antarctica. 

If 6A1 was only resistant to one or two antibiotics, that would not be particularly noteworthy but this is not the case. The bug is resistant to a lot of antibiotics and extremely resistant to a number of the best drugs on the market today. I won't get into all the details here, but its resistance to the common antibiotics amoxicillin and cefoxitin was far greater than that seen in P. aeruginosa. Resistance to erythromycin was ten times greater than that seen in P. aeruginosa. Worse, against ertapenem, a state of the art last resort antibiotic, the new species proved 180 times more resistant than P. aeruginosa.

Let us all hope that 6A1 remains sequestered in Antarctica for a very very long time.

This research published online in Polar Biology and, while I could not weave it into the science section of The Economist, you can view the original peer reviewed paper here. 

Stand at attention

He's paying more attention this way.

Image courtesy of Rama.

A new study is revealing that people are able to more quickly solve problems that test their ability to pay attention while standing up than when sitting down. This flies in the face of the long held notion that standing up requires us to pay a little bit of attention to keep our balance and that this, in turn, interferes with our ability to entirely pay attention to other matters. It is also this wrongheaded logic that has guided important exams to be taken sitting down. As it turns out, if we were take such exams standing up we'd probably perform better.

Academically, this finding suggests that a great many psychological experiments that have been conducted in the past would yield different results if participants in them were take engage in such experiments while sitting down. It will be interesting to see how the psychological community responds to this. You can read more in The Economist article that I wrote on this here,