Unseen Oscillations

On Brookhaven Bits & Bytes, Steve Kettell brings us up to speed on a new research project taking place beneath a mountain in southern China. The object of study is the neutrino, which can “pass through the Earth and through much of the universe without interacting with anything.” Ethan Siegel explains on Starts With a Bang: “Neutrinos only interact gravitationally and through the weak force. They have no electromagnetic interactions.” And because they have no charge, neutrinos are free to pass between the atoms that make up tangible matter. Steve writes that neutrinos from the sun were first detected in the 1960s—but “only one third of the expected number was observed.” With the new detectors at Daya Bay, scientists can compare the number of neutrinos produced by nuclear reactors with the number detected almost two kilometers down the road. The neutrinos lost in between “would indicate that some of our electron antineutrinos had oscillated into tau antineutrinos, which we cannot physically observe.” Such a result would indicate another source of CP violation in nature and increase our understanding of particle physics.


How to Engage an Undergrad?

It’s mid-August, and the school year is nigh. On Dynamics of Cats, Steinn Sigurðsson provides a blueprint for a successful academic term, and yes, you should take notes. Steinn writes, “Ideally, the primary teaching delivery would be a wise person at the end of a log […] unfortunately wise people are in desperately short supply.” More often the wise person is on the floor of a crowded auditorium. But Steinn believes the lecture is a strong foundation for learning—as long as students build on it “after class, over coffee, on the library steps, over lunch, drinking beer and during the all valuable late night sessions back in the dorms!” Meanwhile, Chad Orzel can’t ignore the “tons of education research showing that a traditional lecture format doesn’t work as well as more active techniques.” This fall, he’ll try to cut his lecturing “down to almost nothing in favor of in-class discussion/ problem solving/ questions/ etc.” But will students come to class prepared? Or will they crack their textbooks on the eve of the exam?

Billions of B-Cells

On We Beasties, Kevin Bonham tells us all his thoughts on GoD—the Generation of Diversity that enables B-cells “to make antibodies that recognize almost any chemical structure that has ever existed or will ever exist.” By recombining three essential pieces of an antibody (with 100, 30, and 6 variants respectively), using enzymes to slice up DNA and stitch it back together, and owing to a little extra variation from our parents and a dash of random nucleotides, B-cells can fabricate about 10 billion different antibodies to intercept viruses, bacteria, and other intruders. On ERV, Abbie tells us that the same antibody can come in five different forms, or isotypes, that fill functional niches in a total immune response. Abbie writes, “Because your immune system is mindless […] this ends up generating a lot of waste, like many evolved systems.” But “it also means youve got a lot of bases covered when you are exposed to a new pathogen.”

Intestinal Directions

On Pharyngula, PZ Myers reports that the curling and packing of intestines (which in humans grow to over twenty feet long) follows “simple mathematical rules” akin to “the Fibonacci spirals we see in the head of a sunflower or the coils of a nautilus shell.” Researchers successfully recreated the characteristic curves of a chick gut using lifeless rubber simulacra, and also predicted them using computer models, proving that although every species has its own stereotypical pattern of gut construction, DNA is not the architect. And in an older post on Dean’s Corner, Dr. Jeffrey Toney shares some stunning false-color images of Drosophila intestines, proving that beauty is not only in the eye of the beholder—it’s also in the belly of the beast.

Death Dealers

On Becoming a Domestic and Laboratory Goddess, Dr. Isis reports that drug-maker Lundbeck “will no longer provide Nembutal to prisons in states where lethal injection is legal.” Nembutal is a barbiturate used in conjunction with two other drugs to execute capital offenders, and an alternative to Sodium Pentothal, which since 2010 has been in short supply. While Lundbeck may stand on merciful principles, Dr. Isis worries that Nembutal will no longer be available as a therapeutic option at U.S. prisons. On Dispatches from the Culture Wars, Ed Brayton writes that Alabama has a higher per-capita rate of execution than the infamous state of Texas. Ed writes, “Alabama is the only state in the nation that allows judges to overrule juries on death penalty decisions.” In other words, even if an Alabaman jury sentences a defendant to life without parole, the judge can order execution—and start looking for a new barbiturate.

Cosmic Breathing Room

On Universe, Claire L. Evans looks back on the starry-eyed futurism of the 1970’s, when Gerard O’Neill envisioned “massive colonies of human habitation in space—self-sustaining environments capable of hosting hundreds of thousands of people.” These colonies, housed in spinning cylinders, “would float in space at Lagrangian points, points of stable gravitational equilibrium located along the path of the moon’s orbit.” Today our ambitions are a bit less grand—and perhaps we should focus on taking care of the perennial spaceship Earth. But with unlimited room to grow and plenty of solar energy, the possiblities for cosmic urbanization are interesting (to say the least). Meanwhile, Greg Laden reports that the Herchel Space Observatory has confirmed the presence of molecular oxygen in space—not enough to breathe outright, but perhaps enough to collect for the space settlements of the future. The O2 was discovered in the Orion star-forming complex, 1300 light-years away.

Nearer to the Stars

NASA’s last shuttle mission has flown, and with no administrative fervor to put a human on Mars, what is humanity’s place in space? On Life at the SETI Institute, Dr. Cynthia Phillips says that for scientific exploration of our solar system, “robots don’t need food or water, they can withstand much more damaging radiation, and, perhaps most importantly, they don’t need to come home at the end of the mission.” Plus, “for the cost of putting two astronauts on the surface of a planet like Mars for a few days or weeks, you could afford an army of robots that could comb the surface of the planet for years.” Yet some of us would rather leave a footprint or plant a flag. Meanwhile private industry will fly the ferries and garbage scows needed to foster life in low Earth orbit.

And on Starts With a Bang, Ethan Siegel picks through galaxies to simulate what no human will ever see: the amalgamation of our galaxy with Andromeda, currently approaching at 100,000 miles per hour.