Wednesday, May 30, 2007
There's a very nasty strain of tuberculosis that is resistant to many drugs (XDR-TB). It's not all that common (2 cases per year in the US). But unfortunately, an XDR-TB infected patient flew on some commercial airline flights, exposing a number of unsuspecting people to this dangerous disease. The risk of illness to others is low, but the search is on to find people who traveled on these flights with the XDR-TB patient.
This brings up serious questions of how to deal with patients who carry dangerous contagious diseases. Can they be confined against their will? Prevented from traveling? What is the fine line between protecting the public and personal freedom?
Friday, May 25, 2007
A female shark gave birth to two baby sharks the other day at a Detroit aquarium. The interesting part is that the mother shark had not been in the presence of a male shark in over six years! How did it happen?
The births have raised questions among scientists as to whether sharks may be able to reproduce parthenogenetically, a mode of reproduction in which the egg is not fertilized....
"Parthenogenesis has been documented in many reptiles," said Sweet. "There are at least five or six species of snakes, and it's been known in salamanders, lizards, and even a breed of turkeys. But any way you look at it, this is strange."
There are possibilities other than parthenogenesis. The Belle Isle white spotted bamboo shark may have been fertilized by a male at a very young age. However, although there have been some random reports of shark species storing sperm for a couple of months or more, six years is a long time, and Sweet thinks in this case it's extremely unlikely.
"We received both of these bamboo sharks from hobbyists, who don't typically keep breeding groups; for one thing their tanks aren't big enough. Usually hobbyists can only buy one egg here and there, and the eggs are typically imported as fertilized eggs. Both the hobbyists who donated these sharks only had one individual. I'm almost dead sure we can rule out long-term sperm storage."
A third possibility is that the Belle Isle bamboo shark is a hermaphrodite, harboring both male and female sex organs, and capable of fertilizing its own eggs.
Wednesday, May 16, 2007
A recent study from Duke and Wake Forest Universities shows that the ability to have compassion for oneself plays an important role in overcoming the challenging events in life:
“Life’s tough enough with little things that happen. Self-compassion helps to eliminate a lot of the anger, depression and pain we experience when things go badly for us,” said Mark R. Leary, a professor of psychology and neuroscience at Duke and lead author of the paper, which includes five peer-reviewed studies.
“Rather than focusing on changing people’s self-evaluations, as many cognitive-behavioral approaches do, self-compassion changes people’s relationship to their self-evaluations,” Leary said. “Self-compassion helps people not to add a layer of self-recrimination on top of whatever bad things happen to them. If people learn only to feel better about themselves but continue to beat themselves up when they fail or make mistakes, they will be unable to cope nondefensively with their difficulties.”
Self-compassion involves three components. They are self-kindness (being kind and understanding toward oneself rather than self-critical); common humanity (viewing one’s negative experiences as a normal part of the human condition); and mindful acceptance (having mindful equanimity rather than over-identifying with painful thoughts and feelings).
So, the next time something bad happens, try not to blame yourself too much.