29 October, 1997

29 October 97

0500L SEVERE WEATHER CONDITION

CONDITION III for all locations.

REGIONAL WEATHER SUMMARY...Glacial outflow continues to dominate the western Ross ice

shelf, providing cool air over the area. Low clouds over McMurdo sound have developed overnight

and will provide mostly cloudy conditions.

TODAY...Mostly cloudy with occasional periods of light snow. Visibility: Unrestricted, occasionally 4-6 miles in snow.

Wind (knots): Northeast 8-12 becoming southeast 15-25.

High Temperature: -13C/+09F. Lowest Wind-chill -36C/-33F

TONIGHT...Mostly cloudy with light snow.

Visibility: Unrestricted, lowering to 3-5 miles in snow.

Wind (knots): Southeast 10-15.

Low temperature: -17C/+01F. Lowest Wind-chill -36C/-33F

THURSDAY...Mostly cloudy becoming partly cloudy.

Visibility: Unrestricted.

Wind (knots): Northeast 10-15.

High Temperature: -12C/+10F. Lowest Wind-chill -29C/-21F

SCOTT BASE 24HR TEMPERATURE FORECAST

High: -16C Low: -20C

ASTRONOMICAL DATA

Next sunrise in February, 1998

YESTERDAY'S EXTREMES - 28 October, 1997

Maximum Temperature: -09C/+16F

Minimum Temperature: -16C/+03 F

Peak Wind: 30 Knots

Lowest wind chill: -42C/-43F

The citrate synthase assay was run today for 5 hours and at two different temperatures in order to see how it would work. Data, as expected, indicated that there was a difference in the reaction rate with temperature. Tomorrow I will do another citrate synthase assay but will take a slightly different approach. I will continue to run the assay for an extended time period, however for each time point I will remove samples from the reaction vessel, stop the reaction with a chemical, and read the data. So far, in the experiments I have done I have let the reaction run continuously and obtained data from the same reaction vessel.

Dr. Arthur Devries is a researcher from the University of Illinois. He is known for his discovery that Antarctic fish have a glycoprotein which keep their tissues from freezing. The temperature of the ocean water here is below freezing, and a major question had been why the fish themselves do not freeze.

Dr. Devries needed blood and various tissues for his studies with the antifreeze protein. I was invited to attend a dissection of one of the large Antarctic Cod (Dissostichus mawsoni) which would serve as a source for this special material The fish was caught in McMurdo Sound at a depth of 1500 feet. It lives near the ocean floor and eats smaller fish. Mawsoni weighs up to 200 pounds and lives more than 40 years. In turn it is eaten by seals and orca (killer whales). In addition to the antifreeze protein they have many other special adaptations. Among them are eyes capable of seeing in dim light and a very high fat content which makes them neutrally bouyant and compensates for their lack of a swim bladder.

I knew these were big fish but I wasn't quite prepared for what I saw. Several 4 - 5 foot specimens were swimming in one of the large tanks in the old sea lab building. As they circled they would occasionally come to the surface and look me square in the eye. One was in a large plastic bag floating on the surface. The bag contained an anesthetic that was used to incapacitate the fish.

The fish was placed in a special device which would hold it in the proper position, sacrificed, and the tissues harvested for scientific research. The entire procedure was much like observing a patient having surgery in an operating room. Although this was fascinating to watch I couldn't help feeling a little sorry for the fish. The air was filled with an unspoken reverence for the magnificent fish which had just given his life so that mankind could learn more about the world he lives in. I returned to my lab feeling enriched by the experience.

Things to ponder:

These days there is a lot of discussion about scientific experimentation which involves vertebrate animals. Give this topic some serious thought and formulate an informed opinion.

1. What is your position on the use of vertebrate animals for scientific research? Why?

2. Brainstorm and make a list of things which are now possible as a result of research which utilized these animals.

3. How do you think research would be affected if this practice were not allowed?

4. What is a glycoprotein anyway? See if you can find out what makes these proteins special.


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