Sunday Science 24/09/17

Here are today’s Sunday Science links, for stories you may have missed in the mainstream media.

Today’s featured image is that iconic mammal the snow leopard, which has been downgraded from “endangered” to “vulnerable” on the IUCN Red List of endangered species. Its fellow mammal, the Christmas island pipistrelle bat, was not so fortunate: it is the first Australian mammal in 50 years to be declared extinct. [Leopard photo Vincent J Musi/NGC, from Nature.]

Defects in next generation solar cells, made of perovskite, can be repaired using light. Perovskite is abundant and cheap, but tends to have flaws which affect its efficiency in solar cells, so this is an important step forward.

A new analysis indicates that achieving the target of limiting global warming to 1.5C set by the Paris Agreement might be more feasible than thought (if still tough going). For a far less technical report on this, there’s a decent news article here.

A dinosaur called Chilesaurus may be the missing link between the plant eaters and theropod dinosaurs, which includes the famous carnivorous ones such as T. rex.

Finally, a sweet little piece on the science in Conan Doyle’s Sherlock Holmes stories, including a couple of neat examples of fiction predicting scientific advances (although the psychology stuff I think is a bit unconvincing). Trivia: Holmes is the only fictional character to be made an honorary Fellow of the Royal Society of Chemistry.

 

CCR5 delta 32: the story of a gene, a mutation, and two of the worst diseases in human history

During the 1980s, there was widespread fear of the AIDS epidemic that was sweeping Northern Europe and America. I was a young child at the time and don’t remember much about it, but by the 1990s my fellow teenagers and I were certainly very well aware of this terrible disease and the importance of safe sexual practices. It seems rather strange (and alarming) to me that there is a whole generation of people here who have grown up without that spectre hanging over them. Modern treatment for HIV, the virus that causes AIDS, has transformed it from a certain death sentence to a something that, with combination antiviral therapy, can be lived with for (so far) a normal lifespan. This is a scientific triumph. The story in less wealthy countries of the world, particularly the ongoing pandemic in Africa, is far less rosy, with a million people worldwide dying of the disease last year.

During those turbulent times, stories emerged of people – usually European or American homosexual men, who were the main victims among those populations at that time – who never got the disease, despite repeated exposure. Of course, it’s usually the case that there are resistant individuals to diseases in human populations, but this was a brand new disease spreading, and mutating, incredibly rapidly. Whatever was different about their genes, it was present at their birth, long before the pandemic started. What was this genetic change that meant they could survive what was then unsurvivable, and even not to catch it all? 

Sunday Science 17/09/17

Another “proper” post will be coming soon, but in the meantime, here’s my Sunday Science links. You’ll have noticed by now that when I say “science” in this context I mean everything even tangentially related to it.

It’s the 30th anniversary of the Montreal Protocol on Substances that deplete the ozone layer. (Link includes a youtube video). It’s worth noting that implementing the protocol not only saved the ozone layer, it saved thousands of lives, and billions of pounds. We can see the same principle applying to the problem of climate change now: not doing something will cost far more than doing something (probably it already is). The featured image shows the thickness of the ozone layer over time, with warmer colours indicating greater thickness (credit NASA/NOAA: for full details see bottom of post).

Directly following on from that, I’m pleased to see that the UK has become the first nation to commit to the Kigali amendment to the Montreal Protocol, committing us to reducing hydrofluorocarbon greenhouse gases (HFCs) by 85% between 2019 and 2036. These don’t harm the ozone layer, but have a global warming potential thousands of times more potent than carbon dioxide. (Thanks for doing something good for once, Michael Gove MP).

And while I’m on climate change, here’s an interesting idea about an insurance levy to fund climate adaptation and mitigation. I confess I’m not enough of an economist to know if this is viable, but it sounds like an interesting idea.

Another potential use for AI: detecting Alzheimer’s-related changes in the brain years before symptoms emerge.

Yet more evidence of the complicated inter-relationships between microbes, our immune systems and us. Two studies in mice have provided evidence that certain infections can provoke an immune response which affects the developing embryo, increasing the risk of autism.

I’m including this random link here as I find it an interesting study, but it’s behind Science’s paywall, annoyingly. Is an environmental pollutant masculinising crocodiles? 

Finally, this isn’t really a science story, but it’s a stonking piece about the crazy week one scientist had that led to her being awarded the grant for the work that would lead to the discovery of the BRCA1 inherited breast cancer gene. There’s a youtube video of her telling her story here if you prefer. Hat tip to Dr Laura Flinn Whitworth for linking that.

Featured image credit NASA/NOAA
This shows the thickness of the Earth’s ozone layer on January 27th from 1982 to 2012. This atmospheric layer protects Earth from dangerous levels of solar ultraviolet radiation. The thickness is measured in Dobson units, in this image, smaller amounts of overhead ozone are shown in blue, while larger amounts are shown in orange and yellow.  These ozone measurements begin with the Nimbus 7 satellite; continue with the Earth Probe Total Ozone Mapping Spectrometer (EP TOMS); the Ozone Monitoring Instrument (OMI) aboard the Aura satellite; and the most recent, the Ozone Mapper Profiler Suite (OMPS) aboard the satellite Suomi National Polar-orbiting Partnership (NPP). Suomi NPP is a partnership between NASA, NOAA and the Department of Defense.

Sunday Science links, 10/09/17

Does some music send a chill down your spine and give you goosebumps? If so, you may have a special brain architecture. A study has shown that people that report experiencing “chills” whilst listening to music have higher white matter connectivity between the parts of their brains responsible for hearing and those involved in emotional and social processing. Interestingly, it didn’t correlate with ethnicity, gender, personality or musical training. Link is the to the full open access study.

Are humans still evolving? It’s a thorny question that still vexes researchers. A new study (open access) suggests that gene variants that shorten lifespan, such as the APOE4 variant, which is associated with Alzheimer’s risk, are being selected against. The most interesting – and surprising – finding is that genes for delayed puberty and childbearing are associated with longevity. There’s a readable news summary of it here.

I’m putting a link here to a fascinating and illuminating essay on pseudoscience. Unfortunately it’s not open access, but if you do have institutional access, it’s well worth a read.

Finally, in light of the recent unprecedented hurricane activity in the Caribbean (pictured), I thought I’d put some links up about the supporting science from reliable sources. There’s a quick piece at FactCheck here about Hurricane Harvey, and how much can be attributed to climate change, and an extensive site with data and links to original research from the Geophysical Fluid Dynamics Laboratory here. It has an executive summary on the front page which is good. Regarding that extensive data…the language of scientists is always cautious, which is perhaps why many people find them unconvincing, compared to the certain, simplistic soundbites of politicians and the media. This is because the nature of our work demands accuracy. We don’t say something is certain when it’s 90% probability, because only 100% is certain. The fact remains though, that increased hurricane strength and frequency due to rising global temperatures has been predicted for many years, for sound theoretical reasons as well as being apparent from trends in the recorded data. What we are seeing now we were warned against. It’s up to us what we do about it.

Satellite image from NASA.

Sunday Science stories 03/09/17

This week in Sunday Science links…

(1) Doubts have been raised about that Nature paper that used CRISPR to correct a lethal heart mutation in human embryos. Whenever a landmark paper is published, you often get some hard questions – significant breakthroughs require significant evidence. The criticisms raise valid questions, but I suspect the answer will be: “We need more evidence..and we’ll get it.”

(2) Where is all the plastic in the oceans going? The amount of plastic we discard and that ends up in the oceans is vast and horrifying. This is why some governments are mooting ideas such as a desposit-return scheme for plastic bottles. However, we still don’t know where in the oceans it’s all ending up. This article had a number of surprises for me: I did not know such a vast amount of the plastic in the ocean was discarded fishing gear, for example.

(3) And finally, this week’s featured image is a still from NASA’s grand finale short video of the Cassini spacecraft over Saturn. The spacecraft is nearing the end of it’s epic mission and will execute a planned burnout in the atmosphere of Saturn on September 15th. There is more information, including that video short, which is like a trailer for an epic scifi movie and is absolutely beautiful, here. The video linked below is the much longer NASA news conference:

 

Image credit: NASA/JPL