1

General Science / Can dogs get carsick?

« on: 01/06/2007 18:24:29 »

I have one dog that gets carsick, and two that do not.

2

Physiology & Medicine / rats resistant to poisons.

« on: 26/04/2007 17:24:05 »

There's a really cool age-related element to this, and I use this story to emphasize to my students that developmental changes are important.

Strychnine is a common rodenticide. Baby mice and rats are unaffected by it - only the adults are killed. If you read the package directions, they will tell you treat again 3 weeks after the initial treatment. This gives the babies who were spared a chance to grow up, and then die from the new batch of poison.

The reason for this is that the babies express a type of glycine receptor in their spinal cord neurons and brains that is unaffected by strychnine. As the animals grow up, they replace the baby type with an adult form that happens to be efficiently blocked by strychnine, causing the adults to have seizures and die.

3

Physiology & Medicine / Daily contact lenses - what can happen when you wear them for a week?!

« on: 23/04/2007 16:32:55 »

Infections and blindness can result from wearing these lenses too long.

The lens material is thinner, and more permeable to oxygen and water than standard lenses. The increased permeablility to water means that it's easier for bacteria and fungi to set up housekeeping in the lens.

4

Physiology & Medicine / RDA

« on: 23/04/2007 16:26:57 »

This is a good question. RDA quantities were originally set by noting what minimum prevented illness. It has been argued that the quantity for optimal health could be much greater.

5

Physiology & Medicine / Can one get very comfortable corrective contact lenses for ASTIGMATISMS?

« on: 23/04/2007 16:23:42 »

There are contacts useful for many cases of astigmatism. They are called "toric" and are made with multiple curvatures to the lens as well as a stabilizing system to keep them from rotating about. It may be advisable to find an eye doctor who specializes in contact lenses - fitting these is especially critical.

6

Physiology & Medicine / Tell me about Congestive heart failure/complications from stress and insomnia ?

« on: 29/03/2007 16:22:57 »

It sounds to me like you need someone other than this MD to speak to. Many clinics & hospitals now are recongnizing a need for this sort of thing. Does your local medical facility have someone called a patient educator? or patient advocate?

7

Chemistry / Gimme some Skunk !....pooo !..take it away !!

« on: 24/03/2007 16:53:05 »

Sunlight encourages the hops in beer to form sulfur compounds very similar to those made by skunks. Ever have a beer, probably from green or clear glass bottles, that smelled and tasted sulfury? In the States, much of the Heinekin, Grolsch, Pilsner Urquell, Sam Smith, suffers from this problem. This leads some Americans to think European beer is skunky and awful! Poor things!

8

Physiology & Medicine / Re: Is stomach acid present in vomit?

« on: 24/03/2007 16:45:47 »

Another hallmark of bulimia is sores that never heal on the fingers used to induce vomiting. There certainly is stomach acid coming up, but it is buffered somewhat by food in the stomach.

9

Just Chat! / Science songs

« on: 09/03/2007 22:46:22 »

Sodium Chloride

Just a little drop [atom] of chlorine, valence minus one
Swimming through the sea, diggin' the scene, just havin' fun
She's not worried about the shape or size of her outer shell--
  it's fun to ionize
Just a little atom of chlorine with an unfilled shell.

Somewhere in that sea lurks handsome sodium
With enough eletrons on his outside shell plus another one
"Somewhere in this deep blue sea, there is a negative
  for my extra energy
Yes somewhere in this foam, my positive will find a home

Then unsuspecting chlorine felt a magnetic pull
She looked down and her outside shell was full!
Sodium cried "What a gas, be my bride,
And I'll change your name from chlorine to chloride!"

Now the sea evaporates to make the clouds for rain and snow,
Leaving her chemical conpounds in the absence of H2O
But the crystals that wash upon the shor are happy ones,
     so if you never thought before,
Think of the love that you eat ... when you salt your meat!

Recorded by Kate and Ann McGarrigle

10

Chemistry / Potatoe salt, sea salt, regular salt, LO salt..what's the difference ?

« on: 06/03/2007 15:11:45 »

Table salt is sodium chloride, sometimes with some iodide added to prevent goiter. All the commercially available reduced sodium salt alternatives that I've seen replace some fraction of the sodium chloride (NaCl) with potassium chloride (KCl). KCl tastes almost as salty as NaCl to most people, but some folks also perceive an unpleasant soapy flavor. 
Sea salt is special because it includes magnesium chloride and a bunch of other salt compounds, mostly in small proportion to sodium chloride, but these do affect taste and texture.
You've got me on potato salt. Is that a UK thing?

11

Plant Sciences, Zoology & Evolution / Dog !@#$ repellant

« on: 01/02/2007 22:01:55 »

I wouldn't expose myself to mothballs.

My dogs only go in the house if they've been confined too long or if they are upset for some reason.

Does the dog need more frequent trips outside? Does she not feel good about you, or living with you? Does she miss your sister?

12

Physiology & Medicine / Armpit hair !!..What is that all about ?

« on: 29/01/2007 15:31:36 »

I think we need a olfaction specialist to weigh in on this, but I was taught that the hair in your arm-pits (and leg-pit) was there to hold your smell, your pheromones, to help attract and keep mates. A very prmimitive olfaction cue for mating.

13

Chemistry / What is the most potent /toxic poison known ?

« on: 26/01/2007 15:49:53 »

You are correct that it comes from a natural source, but without human interference, it doesn't become the incredibly potent toxin we know as ricin. Undercooked castor beans aren't in the same category of deadliness as the purified ricin. Just a matter of degree, I know. But a matter of degree is all that separates useful drugs from poisons. Look at what they've done with botulinum toxin - what used to be a reason to throw out dented cans of food has become expensive BoTox for wrinkles!

14

General Science / Does one need an advanced degree in order to be considered a scientist?

« on: 10/01/2007 18:14:33 »

I think it's one's approach to science that truly makes a scientist. We (in my American university) try to teach the scientific method to our students, but some never really learn to think that way, although they can learn to say and do the things requireed to get a degree. Other students think like scientists with no training at all. Most children do naturally.

The scientific method: formulate an hypothesis based on observation; test the hypothesis ; accept or reject the hypothesis on the basis of the test.

15

Chemistry / Re: What is the most potent /toxic poison known ?

« on: 15/12/2006 15:37:38 »

No, I think I'd have to go back to school for a few years before I'd be qualified to dispense drugs to the public, at least in the US.

I work in lab where we try to figure how neurotransmitter receptor/ion channels function. Some of the nasty neurotoxins are very useful tools for us in our experiments.

But this totally off your original question - maybe it would be a good thread on its own.

16

Chemistry / Re: What is the most potent /toxic poison known ?

« on: 14/12/2006 22:22:46 »

LD₅₀is the way that pharmacologists measure lethality. It's the amount of a toxin that must be given in order to cause death in 50% of the animals it was given to. Tetrodotoxin, botulinum toxin and ricin all have LD₅₀values around 1 ng/kg (depending on exact form of the toxin, route of adminstration and species).
Tetrodotoxin is associated with Fugu poisoning (Fugu is pufferfish sushi) and zombies. See the movie and/or book called the Serpent and the Rainbow for a popular treatment of the story, or Wade Davis's books & article for more serious information. Botulinum toxin is found in improperly made or sealed canned goods. Ricin is man-made.

And I'd like to take a moment to point out that I am a neuropharmacologist, not a bad sushi chef, homecanner or terrorist.

17

Radio Show & Podcast Feedback / Re: Environmentally friendly holidays

« on: 13/12/2006 17:15:06 »

Ok, I have now come up with two answers for my own question.

One is to bring my own shopping bags or tote bags when I shop. Cuts down on the trash I have to take out, and the trash that goes in the landfill.

The other is a gift idea. I've been pleased with compact fluorescent light bulbs in all my light fixtures except the reading lamps. So I'm giving these bulbs to a number of friends and family this year. If more people try them, maybe more people will switch to them.

Other ideas?

18

Just Chat! / Re: Have you Ever deep fried a turkey?

« on: 21/11/2006 17:39:08 »

I'm sure you can, just make it sure you use something that won't smoke at 350 F.

19

Physiology & Medicine / Re: What happened to me exactly?

« on: 21/11/2006 16:34:28 »

Sounds like your Valsalva maneuvuer caused a temporary drop in blood pressure, resulting in loss of consciousness.

No long term problems are likely to ensue, as long as you don't do this repeatedly. So don't.

20

Just Chat! / Re: Have you Ever deep fried a turkey?

« on: 21/11/2006 16:27:12 »

I have consulted with a local expert on the subject. Dave's right - start with a dry, completely thawed bird. Pre-dip the bird in cold oil away from the fire beforehand to test the level of the oil - you want to cover the bird, but the vessel should be no more than 2/3 full. Oil overflow is another common way to start a fire. Lots of folks inject brine/oil/seasoning mixtures into the meat before it gets fried. Heat the oil (usually peanut oil, but then again, they grow peanuts around here) to 350 F, making sure that the oil level will not rise too high for the vessel once the bird is added. Fry 3 min per pound. And then 5 min more. My expert suggests that you turn off the flame before using tongs to remove the turkey basket from the oil. And have another person there also with tongs (or those silicone potholder gloves), to help if you. Or to use that fire extinguisher.
Bon appetit, y'all!