Featured image is that of an interactive map of vaccine-preventable disease outbreaks across the globe, created by the Council on Foreign Relations. You can find it, and explore it yourself, at this link.
professor in molecular biology here at Princeton. His research focuses on immune responses to human pathogens – specifically those infecting the liver, including hepatitis B and C viruses, yellow fever and dengue viruses and parasites causing malaria in humans. His group combines methods in tissue engineering, molecular virology and pathogenesis, and animal construction, to create and apply technologies to study human liver diseases caused by infectious diseases and if possible intervene in them. Specifically, he works to create “humanized mice” so we can study in lab mice diseases that typically only infect humans (and other very related species like great apes). In this interview, he discusses how his lab does this and the importance of this research.
I asked Professor Ploss to come speak with us because this topic of infectious diseases is incredibly important. Almost a quarter of the all human deaths worldwide occur due to infectious diseases. And, according to the WHO, in high-income countries like the United States, 7 in every 10 deaths are among people aged 70 years and older, and we perish primarily due to non-communicable diseases like cardiovascular diseases and cancer.
In contrast, in low-income countries nearly 4 in every 10 deaths are among children under 15 years, with only 2 in every 10 deaths are among people aged 70 years and older. In low income countries people predominantly die of infectious diseases like the ones studied by Professor Ploss.
Featured Image: The sky, as viewed from New Mexico or Chile by Sloan Digital Sky Survey. Pointed out is a quasar at extreme redshift, almost 15 billion light years away.
Dr. Chuck Steidel, Caltech astrophysicist and former WPRB DJ, was kind enough to come into the studio during a visit to Princeton several weeks ago. He and his son Nicky (a current DJ at the station) were putting together a clash-of-generations show, so we snagged him for a talk about galaxy formation, extreme redshift, and next-generation telescopes. After that, Stevie brings us a highlight of recent LIGO results: more black-hole mergers have been detected!
Chuck is interested in the ancient universe. Back in those days, soon after the Big Bang, the first clouds of gas were clumping together to form rocks and stars. It was a chaotic time: stars were igniting at alarming rates, and UV radiation would have caused serious sunburns for creatures like us. But understanding this period can tell us how early stars formed–which helps us learn how stars progressed to form complicated elements like carbon and oxygen.
Of course, looking at something so old is not easy: it’s so far away that not much light reaches us, and the light that does has actually warped. Since the universe is expanding, the light gets redder and redder as it travels. If our telescopes on Earth can see enough light to detect these ancient star clusters, it can use how “red” the light gets as a measure of how far away the galaxy is. And this is a great tool: if a galaxy’s light is “redshifted” enough, Chuck knows it’s an old enough galaxy that it still has stars forming quickly.
Of course, when the light gets redder it gets harder to see. The signal starts to blend in with light emitted from our atmosphere. So, the best plan is to put giant telescopes up in space: they need to be large to collect lots of light, but also far above the Earth to avoid atmospheric defects. Keep in mind, sending telescopes to space costs money and takes time for organizations like NASA to coordinate. As they wait for these projects to develop, astrophysicists use ground telescopes to get initial observations of distant galaxies for hints about the better data to come.
One example of a next-generation telescope, steps beyond Hubble in many ways, is the upcoming James Webb Space Telescope. Not only will it have much finer resolution in the infrared for seeing distant galaxies, it’s fitted with a sensitive spectrometer to measure the precise colors of these objects. And Chuck is especially excited about that, because it will allow him to learn what elements are being churned up in these early galaxies. For now, the team takes measurements on two ground telescopes: Keck in Hawaii and Palomar in San Diego.
In the end, Chuck and I agree that science done just to satisfy human curiosity is a worthwhile pursuit. It may not lead to a better app or cure cancer, but most humans wonder about the universe outside our planet. Science for science’s sake might lead to technology we use elsewhere, but advancement is not the main point-and that’s OK. We close out with Chuck’s recollections of summers spent in the WPRB basement, where he hosted shows every day and often visited City Gardens in Trenton to interview alternative bands passing through.
After the interview, Stevie brings us more exciting news concerning our detection of gravity waves. You’ve heard in the news about LIGO’s first discovery, where they heard two black holes merge together from a billion light years away. The team has spent decades building and
perfecting a massive laser observatory, one that measures tiny shifts in laser light to detect small movements in the structure of space. Only massive gravitational events (like collisions between black holes and neutron stars) can cause movements this big. And it’s getting better, because LIGO just announced a second detection of gravitational waves that they found in December. With this development, it appears even more likely that we can use gravity-wave observations to tell us about the most massive things in our universe. So stay tuned for more revolutionary science from the scientists at LIGO!
As always, the playlist is either below or at WPRB.com.
In this week’s These Vibes, the great non-fiction writer and New York Times bestselling author Mary Roach called in to the studio to discuss her new book Grunt: The Curious Science of Humans at War. Her past works include Gulp: Adventures on the Alimentary Canal, Packing for Mars: The Curious Science of Life in the Void, and Stiff: The Curious Lives of Human Cadavers.
In Grunt, Roach tackles the varied and interesting science and scientists behind everything that could possibly be done to keep a human beings intact – in all meanings of the word – in the extreme and often bizarre circumstances of war. Of course, it can’t cover everything, but the many topics include heat exhaustion, sleep deprivation on submarines, using maggots to clean decaying wounds (beginning on the battlefield, but now extending to difficult to treat infections), the testing and careful choices made by military uniform designers, misadventures in shark repellant, and quite a bit more. One might think that a topic like how they make and test the fabric for an infantry uniform would be really dry – but it’s really…not. Roach has an informal style that somehow manages to handle dark and serious topics with care, but without being too over-bearing. Grunt is both light-hearted and big-hearted, while being outstandingly informative, and without ever – not for a second – being dry. (She has a similar style to Bill Bryson, an author I love dearly. He wrote A Walk in the Woods and A Shot History of Nearly Everything, just to name a couple.)
Clearly, I sincerely enjoyed reading this book. There’s this kind of interplay between what we naively think should be the case in a situation (e.g. maggots are gross and we should steer clear) and what’s actually going on when you (or Mary Roach) do a bit of research (maggots are outstanding for cleaning difficult wounds).
As I was reading I kind of came to think of it as a nerd’s beach read. Do pick it up!
Update: Mary Roach did a fun question/answer on the various terms she learned while researching for Grunt. Check it out here:
(Featured image above is from exeterstreethall.org.)
Today we discussed political psychology with Kabir Khanna, doctoral researcher in politics here at Princeton University. Kabir’s specialty is political psychology and public opinion.
We discuss both the polarized partisanship of elected officials, and how that compares to the electorate. More specifically, Kabir explained that though it is clear that politicians have become more extreme on the liberal/conservative spectrum, we don’t quite know if the electorate as a whole has done the same – this is much harder to divine. Kabir discussed some methods of surveying the population to get a better handle on the truth of the situation. In fact, “the truth” and how to get there was much of our musings on today’s show.
This of course led us to discuss surveys, polls, and statistics. In particular, we discuss the details of some of Kabir’s work – which was featured in The New York Times’, The Upshot earlier this year. The work focused on how our opinion of the current state of the economy is affected by our politics, and how that affects our statement of factual pieces of information.
group 2 was given the same quiz and told they’d get a dollar for every question they answered accurately, and
group 3 again received the same quiz, but instead of getting a dollar for correct answers they were directly encouraged to be as accurate as possible.
The study found that “…[w]hen survey respondents were offered a small cash reward — a dollar or two — for producing a correct answer about the unemployment rate and other economic conditions, they were more likely to be accurate and less likely to produce an answer that fit their partisan biases.” (From the Upshot article, a very nice summary of this study and a complementary one by a group at Yale University.)
Featured image is of gravitational lensing in Hubble Deep Field images. See how there’s copies of galaxies and smudging. These distortions in the image are due to large massive astronomical masses between Earth and the galaxies being imaged. Photo credit: NASA
**Apologies to Professor Spergel and listeners for the poor sound quality in part 1 of the interview. We were having trouble with mics, but it was fixed for the remainder of the interview.**
Professor Spergel is known for having incredible depth and breadth of knowledge in astrophysics. In part 1, he takes us through his research spanning astronomical scales from planets to our entire universe. In part 2, we delve in to dark matter and energy, the strangeness of our universe, and the WFIRST satellite (Spergel is co-chair of the NASA science team). In the last part we answer a few listener questions which brings us to the risks involved in astronomy, the formation of our solar system (the planet Venus is weird, but it’s not a spaceship), and archeoastronomy.