29 March 2011 - Bullied Mouse Braaaaiiiins

I reserve the right to skip blogging for the next few weeks if:

• I wind up getting that wrist surgery I desperately need
• There is not time for at least four hours of sleep
• I'm rushing through several weeks of material to pass the last couple of weeks of class I have left
• I'm out of town (a-freakin-gain)

Hilariously, that means I might not be blogging much.  But every morning that I can, I will!  Yaaaayscience.

No really, ya can't make this up.  I currently have enough obligations in my life to keep a small village busy and I'm searching for change in the couch to fill my gas tank (how do I manage to be in a different town one-two times a week when I work every single night?  Hey, overtime will cover it, right?  Right?  RIGHT??)

Enough of that.  Y'all have your busies, too, and that's why I do this thing!




Today's post is on mouse brains.


It seems like basic logic that a mouse who is bullied learns to be more cautious around new mice, but there's more to it than that.  Mice were placed in with bigger, meaner mice for ten minutes (I breed mice, and this makes me cringe to think about - they don't need that ten minutes to kill each other if they're serious!), then separated but left close enough to still induce stress.  They then tried placing the mice with larger, but nonthreatening (how do they figure...) mice and noted behavioral changes consistent with fear, anxiety, and cautiousness.  They then checked out the brain and noted that they had a markedly higher sensitivity to vasporessin, an important hormone associated with the behavior (and other behaviors, including in people).

Mice that were given vasopressin blockers showed less of the wary behavior when placed in with the nonthreatening mice.

You know, I am absolutely FOR using animals in labs.  I believe we have excellent standards in place by IACUC and have seen firsthand how strict the inspections are.  But man, the mouse breeder in me just really knows how serious male aggression in mice is.  They don't need ten minutes, man.  In an enclosure with little or no cover, they can rip each other right apart.  It's like cichlids.  Just, yipes.

What I'm REALLY curious about is how they tested with "non-threatening" mice.  One assumes, based on the territorial statement in the article, that the mice being tested are male.  Females can be aggressive but this is pretty rare and short-lived as they sort out a pecking order in the colony.  So if you're putting in nonthreatening mice to examine followup behaviors, how do you get a nonthreatening mouse?  It has to be male, or you have to take into account sexual hormones.  It has to be a nonfamiliar mouse or you have to take into account imprinting and familiarity, which can also incorporate hormones and scent.  So you have to have a completely new, male mouse.

Just how do you plan on getting new mouse not to attack?  Eh, I know there is a lot more going on than the summary shows, but I would LOVE to read the actual paper.  Alas, I have only access to the abstract.  :)






See you guys soon!
-Miss Mouse






References and Links:
Mouse Bullies (Physorg):
http://www.physorg.com/news/2011-03-bullying-brain-chemistry-anxiety.html

Mouse Bullies with Bigger Words (ScienceDirect):

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T0P-52C3K4S-2&_user=10&_coverDate=03%2F11%2F2011&_rdoc=1&_fmt=high&_orig=gateway&_origin=gateway&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=b963eecbd72b883ea4fa2181c97afa12&searchtype=a

27 March 2010 - Eggs, Nano-Healers, and Baby Stars

Hellos!

I just came across an article stating that mother birds leave “messages” for their chicks within the eggs, so that the chicks develop differently when they hatch.  The association seen here is that chicks (canaries, in this experiment) born from “generous” (well-fed?) parents beg more as adolescents, where as eggs birthed by stingier parents beg less.  This was tested by switching the eggs between two mothers of said habits/nutrition and noting the begging done by the chicks.  This makes two interesting points, imo.  First, depending on at what point in nesting the eggs were switched, the development of feeding expectations has less to do with the care of the egg and more to do with the signals within once laid.  This might not have been news to them, but it was pretty new to me.  Second, as the article points out, the begging behavior which corresponds with the two different conditions seems to be more focused on the energy necessary to be expended by the chick, in constant asking for food, and less to do with the mother’s convenience.  I wonder if this will bring about a new form of selection in birds?

Researchers at the Los Alamos National Lab have recently put forth findings by computer simulations of nanocrystalline materials “healing” damage to nuclear reactors by exposure to high radiation.  Basically, radiation hitting the materials of the reactor cause some atoms to be forced out of place, leaving a tiny hole where they used to be.  The frequent damage over time causes the material to become affected in a nasty way.  However, nanocrystalline materials have been shown, through this program in various simulations, to trap or “load” these lost particles from damage, then, and this is the surprise part, to “unload” these later on into gaps in the material near them, filling in the damage caused by radiation and effectively healing it.  Now, we were already pretty sure they took in these particles in the first place, but releasing them into nearby gaps?  That’s pretty cool.  Now, this is definitely outside my expertise, so if you’d like a better explanation of how they did it and what they found, check out the link at the bottom of this post for the report in Science Daily.  :)

Last for today, astronomers have captured beautiful and amazing photographs of a “star nursery” from 10 billion light-years away.  Normally, this would be a tough thing to accomplish.  However, very large galaxy clusters happen to be in the way, bending the light just enough for us to get a terrific view.  Apparently, the effect of those clusters makes the nursery (SMMJ2135-0102) appear 16 times larger.  Check out the photo gallery here:  Photo Galleries at PopSci

Thanks for reading, and I’ll see you Tuesday with more Science!
-Miss Mouse

References and Links:
Egg Messages

http://www.sciencedaily.com/releases/2010/03/100311141209.htm

Self-Healing Nuclear Reactors

http://www.sciencedaily.com/releases/2010/03/100325151347.htm

Bending Light to See a Star Nursery

http://www.popsci.com/science/article/2010-03/bending-gravity-researchers-capture-star-birthing-region-10-billion-light-years-away