science and mathematics: December 2007 Archives

NASA has coined galaxy 3C321 the "Death Star," so named because the black hole at its center is sending a huge jet of energy at another galaxy close by, punching into the fabric of that neighbouring galaxy:

"We've seen many jets produced by black holes, but this is the first time we've seen one punch into another galaxy like we're seeing here," said Dan Evans, a scientist at the Harvard-Smithsonian Center for Astrophysics and the leader of the study. "This jet could be causing all sorts of problems for the smaller galaxy it is pummeling."

Being targeted by a jet of high energy particles emitting gamma and X-ray radiation might suck for a galaxy, but it's been suggested that the injection of energy and mass into the smaller galaxy might eventually encourage the formation of new planets and star systems in the target galaxy. A galactic Phoenix effect, if you will.

Update: One of my friends asked me how a jet of radiation could be escaping a black hole and slamming into another galaxy beside it, so I replied with the following mini Astrophysics lesson I thought ya'll might find interesting, in case you have the same question:

Only when you cross the event horizon near the black hole can energy or matter not escape from it. Since black holes are massive gravitational sinkholes, they pull everything around them towards them. This causes massive amounts of matter to be compressed near the black hole, some of this matter reacts because of the presence of other trapped matter and the tremendous compression that goes on and therefore creates massive amounts of radiation.

All this happens both inside and outside the event horizon. The radiation produced outside the event horizon, given enough energy, can escape the gravitational anomaly of the black hole and travel away from it.

An organised jet stream of radiation is a result of the organisation and rotation of the matter caused by the gravitational anomaly surrounding the black hole. It's like a shaped funnel in space.

Reuters has released their slideshow of the 2007 "Pictures of the Year." It's always amazing to see how much can happen in one year.

WARNING: The link resizes your window. I really, really hate it when websites resize my window. It's incredibly bad interface design. Leave my window how I want it, damn it. You're not the only tab open in my window, so hands off!

It always annoys me to no end when a scientific study comes to bad conclusions based on incomplete data, and it makes it even worse when the reporting is just as bad in not criticising the flaws in the conclusions.

Such was the case today with a new study that is making the rounds, and I learned of from PhysOrg. The title of the article says it all: "In fruit flies, homosexuality is biological but not hard-wired."

I braced myself for bad science, and there it was:

To test this, he and his colleagues genetically altered synapse strength independent of GB, and also fed the flies drugs that can alter synapse strength. As predicted, they were able to turn fly homosexuality on and off -- and within hours.

"It was amazing. I never thought we'd be able to do that sort of thing, because sexual orientation is supposed to be hard-wired," he said. "This fundamentally changes how we think about this behavior."

Basically, the scientists in the study found that if they genetically or chemically altered certain types of synapse activity within a fly's brain, they could "turn homosexuality on/off."

The data showed that otherwise heterosexual flies would start courting indiscriminately if this specific synapse strength was altered, and that's the key part of the data, barely hinted at by only one sentence in the article amidst the sensationalism:

"Homosexual courtship might be sort of an 'overreaction' to sexual stimuli," he explained.

I say hint because the data did not include tests on naturally homosexual flies. There was no control for the experiment and no negative test. This makes their conclusions fallacious and sensationalist.

The conclusion they can draw from the data is that when certain synapse strengths are modified, flies become hyper-sexual and display a tendency to mate indiscriminately in regards to sex. This hyper sexual behaviour fades when the synapses return to normal, and heterosexual flies again assert a preference for mating with the opposite gender.

The conclusion that they can turn homosexual behaviour on and off at will is bad science, and it really grinds my gears.

Study Shows Why the Flu Likes Winter from the NYTimes.

The answer, they say, has to do with the virus itself. It is more stable and stays in the air longer when air is cold and dry, the exact conditions for much of the flu season.

“Influenza virus is more likely to be transmitted during winter on the way to the subway than in a warm room,” said Peter Palese, a flu researcher who is professor and chairman of the microbiology department at Mount Sinai School of Medicine in New York and the lead author of the flu study.

It's those damn kids, I tell you.

“We know one of the largest factors is kids in school — most of the major epidemics are traced to children,” said Dr. Jonathan McCullers, a flu researcher at St. Jude Children’s Research Hospital in Memphis. “But that still does not explain wintertime. We don’t see flu in September and October.”

As for the crowding argument, Dr. McCullers said, “That never made sense.” People work all year round and crowd into buses and subways and planes no matter what the season.

Okay, maybe not. How about guinea pigs? They're kinda like children, except you can experiment with guinea pigs.

By varying air temperature and humidity in the guinea pigs’ quarters, they discovered that transmission was excellent at 41 degrees. It declined as the temperature rose until, by 86 degrees, the virus was not transmitted at all.

The virus was transmitted best at a low humidity, 20 percent, and not transmitted at all when the humidity reached 80 percent.

The animals also released viruses nearly two days longer at 41 degrees than at a typical room temperature of 68 degrees.

On top of that, the cold air helps the virus to stay viable and the dry air helps them remain in the air because they're in respiratory droplets.

What can you do? The researcher recommends a flu shot. I'll personally be taking antibiotics to protect me against children.

Top Gear reviews the the tiniest of cars, the 1964 Peel P50:

The Theory of Moral Neuroscience, from Reason Online, found through a science blog somewhere that I've lost track of.

Just like monkeys, it turns out that when we see someone perform an action—picking up a glass of water or kicking a ball—our mirror neurons simulate that action in our brains.

When discussing how this plays out for people with autism

In 2005, researchers at the University of California San Diego (UCSD) compared brain wave activity associated with mirror neurons in high functioning individuals with autism spectrum disorders (ASD) and in typical individuals. In normal individuals, mu brain wave activity is suppressed whenever they move their hand, imagine moving their hand, or see someone else move their hand. "The ASD group showed significant mu suppression to self-performed hand movements but not to observed hand movements. These results support the hypothesis of a dysfunctional mirror neuron system in high-functioning individuals with ASD," concluded the study.

Subsequent experiments by Jaime Pineda and his colleagues at UCSD found that individuals with ASD develop compensatory brain mechanisms that allow them to identify correctly the emotions of others and determine their intentions. Mirror neurons are not absent from the brains of ASD people, but they are misfiring. Pineda suggests that neurofeedback retraining might reduce some of the social symptoms of autism.

Of course, the mirror neurons can't be our only source of moral sense, otherwise you can imagine what trouble people with autism would be. The argument is that empathy or some kind of social metacognition, to borrow an ed psych term, is only one contributor to a person's morality

Empathy, the ability to feel someone else's joy, pain, and gratitude, helps guide our pre-reflective moral values.

I'm personally more interested in how much of an effect mirror neurons have on linguistic development, but I don't know how much of an effect something like a mirror neuron would have on development. I have much more research to do. Expect to hear more about this in the future.

Scientists in North Dakota have found what might be the world's best preserved dinosaur mummy, with intact skin, muscle and perhaps even organs:

Preserved by a natural fluke of time and chemistry, the four-ton mummified hadrosaur, a duck-billed herbivore common to North America, could reshape the understanding of dinosaurs and their habitat, its finders say.

"There is no doubt about it that this dinosaur is a very, very significant find," said Tyler Lyson, a graduate student in geology at Yale University who discovered the dinosaur in North Dakota.

The money quote:

"When I first saw it in the field, (I thought) 'Shiiiit, that's a really well preserved dinosaur.' It has the potential to be a top-10 dinosaur, globally."

Gotta love it when scientists show their human side.

NASA has released details on the manned Mars mission:

A 400,000kg (880,000lb) Marship would be assembled in orbit using the Ares V cargo launch vehicle for a 900-day mission to the red planet, according to details that have emerged about NASA's new Constellation programme's manned Mars mission.

The spacecraft would take a "minimal crew" to Mars in six to seven months, with the crew spending up to 550 days on the surface, according to the programme's design reference architecture 5.0, currently in development.