A Bit More Detail

Assorted Personal Notations, Essays, and Other Jottings

Posts Tagged ‘science

[BLOG] Some Friday links

  • At Acts of Minor Treason, Andrew Barton is very unhappy with the misuse of the Hugo Award.
  • Anthropology.net notes that DNA has been retrieved from an ancient and mostly fossilized Neanderthal fossil.
  • Centauri Dreams examines the early history of the Milky Way Galaxy.
  • Crooked Timber looks at the controversies over religious liberty.
  • The Dragon’s Gaze considers how extraterrestrial life can be detected through disequilibria in exoplanet atmosphere and notes the recent Alpha Centauri B study.
  • The Dragon’s Tales notes that by 2018 a laser will be deployed on a drone.
  • Geocurrents shares slides from a recent lecture on Yemen.
  • Language Hat examines the Yiddish word “khnyok”.
  • Lawyers, Guns and Money considers the Republican race.
  • Marginal Revolution notes the unpopularity of political jobs among young Americans.
  • The Planetary Society Blog notes SpaceX’s problem with retrieving the first stages of its rockets.
  • Torontoist looks at beekeeping in Toronto.
  • Towleroad notes a Kickstarter fundraiser for Emil Cohen’s photos of queer life in Providence.
  • Transit Toronto notes the expansion of free WiFi throughout the subway system.
  • The Volokh Conspiracy notes that divorce papers can be served via Facebook if it is the most practical alternative.
  • Window on Eurasia fears a summertime Russian attack on Ukraine, notes Russian fears of rebellion at home, and looks at Russian Internet censorship.
  • The World’s Gideon Rachman wonders if the Greek demand for Second World War reparations will bring the Eurozone crisis to a head.
  • Yorkshire Ranter Alex Harrowell notes the essential lack of difference on government spending between Labour and the Tories and looks at flawed computer databases.

[LINK] “Largest HIV outbreak in Indiana history hits tiny community”

The Toronto Star‘s Jennifer Yang describes a terrible epidemic of HIV in the United States, a drug-borne pandemic in Indiana’s Scott County aggravated by public policy and poor public health.

Since December, 89 cases have been reported in Scott County, a region that typically sees five HIV cases a year. Most are in Austin, a crumbling city of about 4,300 located near the Kentucky border.

The crisis has triggered a state of emergency and urgent response measures, including a temporary needle exchange program, which is normally illegal under Indiana state law. But as public health officials scramble to contain the outbreak, a troubling question looms: how could this have happened?

Investigators say the HIV outbreak was caused by another epidemic that has long plagued Scott County: drug addiction. “One hundred per cent of cases have reported IV drug use so far,” Dr. Jerome Adams, Indiana’s health commissioner, told the Star.

While unsafe sex has helped spread the virus, Adams believes this is the “largest or first outbreak of its kind solely related to prescription drug abuse.” In Austin, where public parks are littered with syringes, police are pointing the finger at Opana, the area’s “drug of choice,” a prescription painkiller that can be crushed and injected. In 2012, Reuters reported that Opana was the “new scourge of America,” gaining popularity after the painkiller OxyContin was changed to become more difficult to abuse.

Scott County is one of Indiana’s poorest areas and 17 per cent of people live in poverty, with a median household income of $43,650. “Austin has historically been a poor community,” said Cpl. Carey Huls, a public information officer with Indiana State Police. “Over time, because of joblessness, the drugs crept in.”

Written by Randy McDonald

April 8, 2015 at 10:21 pm

[LINK] “Wooly Mammoth Genes Inserted into Elephant Cells”

The Dragon’s Tales linked last week to this Discovery News report suggesting that the resurrection of the mammoth may not be too far off.

Researchers from Harvard University have successfully inserted genes from a woolly mammoth into living cells from an Asian elephant, the extinct giant’s closest remaining relative.

Harvard geneticist George Church used DNA from Arctic permafrost woolly mammoth samples to copy 14 mammoth genes — emphasizing those related to its chilly lifestyle.

“We prioritized genes associated with cold resistance including hairiness, ear size, subcutaneous fat and, especially, hemoglobin,” Church told The Sunday Times.

Then, using a kind of DNA cut/paste system called CRISPR (clustered regularly interspaced short palindromic repeat), Church dropped the genes into Asian elephant skin cells.

The result? A petri dish of elephant cells functioning normally with mammoth DNA in them, marking the first time mammoth genes have been on the job since the creature went extinct some 4,000 years ago, as Sarah Fecht, from Popular Science, noted.

Written by Randy McDonald

March 30, 2015 at 10:42 pm

[LINK] On the oddity of Nova Vulpeculae 1670, aka CK Vulpeculae

National Geographic‘s Nadia Drake reports on how recent reanalyses of an obscure seventeenth-century nova points to early astronomers’ observation of something very unusual.

For decades, scientists thought the explosion was a classical nova, a stellar outburst that’s less catastrophic than a supernova. But a new look at the remnant left behind by the explosion reveals a more violent history, astronomers report Monday in Nature. Now called CK Vulpeculae, the explosion was what’s called a red transient, produced when two stars violently collide.

Red transients are thought to be a relatively rare type of stellar smashup; based on the chemical elements produced in the collision, this one appears to have been particularly violent, possibly even head-on, says study author Tomasz Kaminski, of the European Southern Observatory.

In 1670, a new star appeared in the sky. Located near the head of Cygnus the Swan, the guest star was first spotted in June. It stuck around through the summer but faded in the fall.

In March 1671, the star reappeared—and over that summer, it shone brighter than ever before. Astronomers of the time, including lunar cartographer Hevelius and Giovanni Domenico Cassini (the namesake of NASA’s Saturn-exploring Cassini spacecraft), kept track of the star’s light until it vanished that October. It made one more feeble appearance in 1672 before disappearing for good.

At the time, astronomers didn’t know what they were looking at. “There would still have been controversy as to whether the nova was in the starry realms or in the Earth’s atmosphere,” says Owen Gingerich, professor emeritus of astronomy and the history of science at the Harvard-Smithsonian Center for Astrophysics.

Written by Randy McDonald

March 27, 2015 at 11:08 pm

[BLOG] Some Wednesday links

  • Gerry Canavan produces his own compendium of interesting links.
  • Centauri Dreams speculates about the colours indicative of extraterrestrial life, and ecologies.
  • Crooked Timber takes a look at Northern Ireland and the legacies of past violence.
  • The Dragon’s Tales reports on a hominid fossil that may indicate a much greater diversity in our ancestral gene pool than we thought.
  • A Fistful of Euros’ Edward Hugh wonders when the European Central Bank will start to taper interest rates.
  • The Frailest Thing warns that the promises of tech giants to free people from the shackles of the past should be seen critically.
  • On St. Patrick’s Day, Joe. My. God. and Michael in Norfolk both note the extent to which attitudes towards GLBT people in Ireland have changed.
  • Lawyers, Guns and Money wonders about the good sense of going off of anti-depressants.
  • Marginal Revolution’s Tyler Cowen proclaims Scarborough to be one of the world’s best food cities.
  • Savage Minds makes the case for anthropologists to aid the post-cyclone people of Vanuatu.
  • Spacing interviews the NDP’s Thomas Mulcair on urban issues.
  • The Volokh Conspiracy’s David Bernstein is unhappy at the consequences for Israel of Netanyahu’s reelection, while Lawyers, Guns and Money looks at income disparities in Israel.
  • Window on Eurasia argues that high inequality and low social mobility in Russia will doom the country, notes the potential for water-driven conflict in Central Asia, and notes Russian interest in acquiring more slots of Muslim pilgrims after Crimea’s annexation.

[LINK] On the possible extensive water oceans of early Mars

The New York Times‘ Marc Kaufman reported on the controversial new suggestion, described in the new Science paper “Strong water isotopic anomalies in the martian atmosphere: Probing current and ancient reservoirs”.

After six years of planetary observations, scientists at NASA say they have found convincing new evidence that ancient Mars had an ocean.

It was probably the size of the Arctic Ocean, larger than previously estimated, the researchers reported on Thursday. The body of water spread across the low-lying plain of the planet’s northern hemisphere for millions of years, they said.

If confirmed, the findings would add significantly to scientists’ understanding of the planet’s history and lend new weight to the view that ancient Mars had everything needed for life to emerge.

“The existence of a northern ocean has been debated for decades, but this is the first time we have such a strong collection of data from around the globe,” said Michael Mumma, principal investigator at NASA’s Goddard Center for Astrobiology and an author of the report, published in the journal Science. “Our results tell us there had to be a northern ocean.”

But other experts said the question was hardly resolved. The ocean remains “a hypothesis,” said Ashwin Vasavada, project scientist of the Curiosity rover mission at the Jet Propulsion Laboratory in Pasadena, Calif.

The Guardian‘s Ian Sample explained the scientists’ methodology.

The scientists used the Keck II telescope and Nasa’s Infrared Telescope Facility, both in Hawaii, and the ESO’s Very Large Telescope in Chile, to make maps of the Martian atmosphere over six years. They looked specifically at how different forms of water molecules in the Martian air varied from place to place over the changing seasons.

Martian water, like that on Earth, contains standard water molecules, made from two hydrogen atoms and one oxygen atom, and another form of water made with a heavy isotope of hydrogen called deuterium. On Mars, water containing normal hydrogen is lost to space over time, but the heavier form is left behind.

When normal water is lost on Mars, the concentration of deuterium in water left behind goes up. The process can be used to infer how much water there used to be on the planet. The higher the concentration of deuterium, the more water has been lost.

The infrared maps show that water near the Martian ice caps is enriched with deuterium. The high concentration means that Mars must have lost a vast amount of water in the past, equivalent to more than six times that now locked up in the planet’s frozen ice caps.

The scientists calculate that the amount of water was enough to create a global ocean that covered the entire surface of Mars to a depth of 137m. But Mars was probably never completely submerged. Based on the Martian terrain today, the scientists believe the water pooled into a much deeper ocean in the low-lying northern plains, creating an ocean that covered nearly a fifth of the planet’s surface. The Atlantic, by comparison, covers about 17% of Earth’s surface.

“Ultimately we can conclude this idea of an ocean covering 20% of the planet which opens the idea of habitability and the evolution of life on the planet,” said Geronimo Villanueva, the first author on the study.

The Vastitas Borealis, the deep and level northern-hemispheric plain, has long been thought of as a possible ancient ocean bed.

The science can be challenged on multiple grounds. For example, are scientists correct in their judgement of Mars’ ancient hydrogen/deuterium ratios? It could go either way if they are wrong. Regardless, this has implications for ancient–and even current?–life on the Red Planet.

Written by Randy McDonald

March 5, 2015 at 11:17 pm

[LINK] “Real Paleo Diet: Early Hominids Ate Just About Everything”

At IFL Science, Ken Sayers notes that, far from cleaving to the paleo diet in vogue now, early hominids have a diverse omnivorous diet.

Reconstructions of human evolution are prone to simple, overly-tidy scenarios. Our ancestors, for example, stood on two legs to look over tall grass, or began to speak because, well, they finally had something to say. Like much of our understanding of early hominid behavior, the imagined diet of our ancestors has also been over-simplified.

Take the trendy Paleo Diet which draws inspiration from how people lived during the Paleolithic or Stone Age that ran from roughly 2.6 million to 10,000 years ago. It encourages practitioners to give up the fruits of modern culinary progress – such as dairy, agricultural products and processed foods – and start living a pseudo-hunter-gatherer lifestyle, something like Lon Chaney Jr. in the film One Million BC. Adherents recommend a very specific “ancestral” menu, replete with certain percentages of energy from carbohydrates, proteins and fats, and suggested levels of physical activity. These prescriptions are drawn mainly from observations of modern humans who live at least a partial hunter-gatherer existence.

But from a scientific standpoint, these kinds of simple characterizations of our ancestors’ behavior generally don’t add up. Recently, fellow anthropologist C. Owen Lovejoy and I took a close look at this crucial question in human behavioral evolution: the origins of hominid diet. We focused on the earliest phase of hominid evolution from roughly 6 to 1.6 million years ago, both before and after the first use of modified stone tools. This time frame includes, in order of appearance, the hominids Ardipithecus and Australopithecus, and the earliest members of our own genus, the comparatively brainy Homo. None of these were modern humans, which appeared much later, but rather our distant forerunners.

We examined the fossil, chemical and archaeological evidence, and also closely considered the foraging behavior of living animals. Why is this crucial? Observing animals in nature for even an hour will provide a ready answer: almost all of what an organism does on a daily basis is simply related to staying alive; that includes activities such as feeding, avoiding predators and setting itself up to reproduce. That’s the evolutionary way.

[. . .]

Researchers Tom Hatley and John Kappelman noted in 1980 that hominids have bunodont – low, with rounded cusps – back teeth that show much in common with bears and pigs. If you’ve watched these animals forage, you know they’ll eat just about anything: tubers, fruits, leafy materials and twigs, invertebrates, honey and vertebrate animals, whether scavenged or hunted. The percentage contribution of each food type to the diet will depend (you guessed it) on the energetic value of specific foods in specific habitats, at specific times of year. Evidence from the entirety of human evolution suggests that our ancestors, and even we as modern humans, are just as omnivorous.

Written by Randy McDonald

March 2, 2015 at 10:18 pm


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