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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