Links for August 2014

  • Jester (Adam Falkowski) on physics breakthroughs:

    This year’s discoveries follow the well-known 5-stage Kübler-Ross pattern: 1) announcement, 2) excitement, 3) debunking, 4) confusion, 5) depression. While BICEP is approaching the end of the cycle, the sterile neutrino dark matter signal reported earlier this year is now entering stage 3.

  • The ultimate bounds on possible nuclides are more-or-less known from first principles.
  • UPower Technologies is a nuclear power start-up backed by Y-Combinator.
  • It is not often appreciated that “[s]mallpox eradication saved more than twice the number of people 20th century world peace would have achieved.” Malaria eradication would be much harder, but the current prospects are encouraging. Relatedly, the method for producing live but attenuated viruses is super neat:

    Attenuated vaccines can be made in several different ways. Some of the most common methods involve passing the disease-causing virus through a series of cell cultures or animal embryos (typically chick embryos). Using chick embryos as an example, the virus is grown in different embryos in a series. With each passage, the virus becomes better at replicating in chick cells, but loses its ability to replicate in human cells. A virus targeted for use in a vaccine may be grown through—“passaged” through—upwards of 200 different embryos or cell cultures. Eventually, the attenuated virus will be unable to replicate well (or at all) in human cells, and can be used in a vaccine. All of the methods that involve passing a virus through a non-human host produce a version of the virus that can still be recognized by the human immune system, but cannot replicate well in a human host.

    When the resulting vaccine virus is given to a human, it will be unable to replicate enough to cause illness, but will still provoke an immune response that can protect against future infection.

  • There seem to be visual processing advantages of dyslexia.
  • After a decade of travel in deep space, the Rosetta spacecraft has reach comet 67P and there is video of the approach:

    The journey was not without excitement:

    On 25 February 2007, the craft was scheduled for a low-altitude bypass of Mars, to correct the trajectory after the first launch attempt in 2003 was delayed by one year. This was not without risk, as the estimated altitude of the flyover manoeuvre was a mere 250 kilometres (160 mi). During that encounter the solar panels could not be used since the craft was in the planet’s shadow, where it would not receive any solar light for 15 minutes, causing a dangerous shortage of power. The craft was therefore put into standby mode, with no possibility to communicate, flying on batteries that were originally not designed for this task. This Mars manoeuvre was therefore nicknamed “The Billion Euro Gamble”.

  • Ebola containment, threats of solar storms, and the alleged violation of the 1987 Intermediate-range Nuclear Forces Treaty are covered in the July round-up of threats to humanity by the Global Catastrophic Risk Institute.

ADDED 2014-8-21 10:30pm

  • is a Kickstarter-like website for independent scientific research. A project led by Gabriel Licina and the team at Science For The Masses are seeking to figure out whether it’s possible to biologically extend the range of human vision into the near infrared on a shoe-string budget of $4,000. Here is the main idea:

    We have developed a protocol to augment human sight to see into the near infrared range through human formation of porphyropsin, the protein complex which grants infrared vision to freshwater fish.

    Retinal, or Vitamin A (A1), which is found bound to opsin proteins is a keystone of the visual pathway. The cone cells are granted sharp color vision by the complex photopsin. The rod cells which provide us with night vision and recognition of movement do so utilizing rhodopsin. Both of the complexes consist of a type of protein bound to retinal. Porphyropsin differs from this in that it doesn’t use retinal, but rather a derivation called 3,4-dehydroretinol, or Vitamin A2 (A2).

    The human body is fully capable of metabolizing and using A2; unfortunately the proteins which allow for transport through cell membranes have nearly 4 times the affinity for A1 compared to A2. We theorize that this can be overcome through a stringent Vitamin A1 restricted diet, supplemented with Vitamin A2.

    Using an Electroretinography, which is an instrument that measures the electrical responses of various cell types in the retina of live human test subjects, they are reporting that subjects administered Vitamin A2 are showing measurable response to 950 nm light who were previously only sensitive to 850 nm light.

    Needless to say, this hasn’t been peer reviewed. There are discussions on Reddit and HackerNews, although there’s very little talk of whether or not this is believable.

    The nominal upper wavelength for visible light is generally quoted to be between 700 nm and 800 nm.

    "Spectral absorption curves of the short (S), medium (M) and long (L) wavelength pigments in human cone and rod (R) cells." Source: Wikipedia.

    "Eye sensitivity function...and luminous efficacy, measured in lumens per watt of optical power". (Log scale.) Source: E. Fred Schubert, "Human eye sensitivity and photometric quantities", Light-Emitting-Diodes-dot-org.

    I couldn’t find a source to determine the longest reported visible wavelength.

Bookmark the permalink.

Leave a Reply

Required fields are marked with a *. Your email address will not be published.

Contact me if the spam filter gives you trouble.

Basic HTML tags like ❮em❯ work. Type [latexpage] somewhere to render LaTeX in $'s. (Details.)