Archive for September, 2007

Come see us!

September 26, 2007

Mike Sullivan writes:

We are about two and a half weeks away from our big, annual open house event, Skidaway Marine Science Day. Thie year it is from noon to 5 pm on Saturday, October 13. In the past, this has been a lot of work but also a lot of fun. Last year, we estimate around 1,500 visitors came out.Skidaway Marine Science Day

This is a very cooperative event among the separate organizations her on our campus. Everyone puts out a welcome mat with displays, programs, tours and hands-on activities. It is a pretty good day for everyone from small children to seniors.

UGA AquariumThis year our highlight is the grand reopening of the University of Georgia Aquarium, which has been closed for renovations for the past two months.

A couple of the research assistants here at Skidaway Institute have also come up with a high-tech treasure hunt using GPS devices. I’m still a little vague on the details but it should also be fun.

One of the areas in which we are heavily involved is offshore ocean observation using remote senors. navy-tower-r2.jpgThis is difficult to explain to people and even more difficult to demonstrate, since the Navy towers we utilize are 20 or more miles off shore. Bill Savidge and Jimmie Williams are building a mock-up of one of their systems which will be set up in the quad in front of our mail building. I’m looking forward to seeing that.

If you are in Savannah that weekend, come on out and see what’s going on here.

What’s an IRMS, and why do I care?

September 20, 2007

Mike Sullivan writes:

I have spent some time over the past two weeks trying to get my arms around some new equipment we are installing. An Isotope Ratio Mass Spectrometer is an impressive name, and Jay Brandesjay-brandes-a.jpg is having two of them installed in his new lab. But what does it do and why should anyone care? It turns out that it is a highly sophisticated piece of analytical equipment, with all sorts of “add-ons” to give it a great deal of flexibility. It’s easy to be dazzled and confused (as I was) by the technical jargon. Jay finally sat me down and explained it to me in a way that even I could understand. Here is the story of what the IRMSs do and why they are a great addition to Skidaway Institute.

There are lots of different kinds of equipment that can analyze samples of chemicals, water, soil, gasses, etc. They can tell you what is in the sample in terms of elements and compounds. The IRMS does similar analysis, but it’s main purpose is to tell you the source of the an element in a sample. For example, if you are looking at water samples from a coastal estuary, you may see a lot of nitrogen and wonder where it came from. Is it naturally occurring, or is it getting into the water from fertlizer run off from a golf course, a sewage plant or animal waste from a farm? The IRMS can help answer that question.

It uses a tool called “stable isotopes.” Let me explain that. (If you already know about stable isotopes, please forgive me for the explantion. You can skip this paragraph.) Most elements come in different forms called isotopes. The different isotopes are distinguished by the number of neutrons in their nucleus’. For example the nucleus of a carbon atom has six protons and most also have six neutrons giving an atomic number of 12. (6 + 6) The carbon atom also has six electons, but they aren’t relevant to this explanation. Less than 1% of carbon atoms also have an extra neutron in their nucleus giving them an atomic number of 13 (6 protons and 7 neutrons). An even smaller percentage of carbon atoms have two extra neutrons (atomic number 14). Carbon 14 is unstable and decays into another element. That is why it is used to date things like ancient bones, but that’s a story for another time. Carbon 13, on the other hand is very stable, hence the term “stable isotope.”

It seems that the ratio of carbon 12 and carbon 13 in a sample will vary according to the source of the sample. That ratio gives the source a signature. Carbon from various plants or animals will have different isotopic signatures that live on after they die, are eaten, decay, etc.

Another example — if you are analyzing the biomass in the sediment a salt marsh, you may want to know what is contributing to the organic material there. The carbon that is contributed from decaying marsh grass like spartina will have a different isotopic signature than carbon coming from phytoplanton, decaying marine animals, run off from the adjacent forest and so on. By analyzing the carbon with an IRMS, you can paint a picture of the sources of organic material that is in the salt marsh.

I just used carbon in salt marsh sediment as an example. The possiblities are endless.

One IRMS is on-line right now and a second is still being built and will be installed early in 2008. At that point, Skidaway Institute will be one of just a handful of labs in the country with this capability. We expect our lab will be used by our scientists, but also that researchers from throughout the Southeast may make use of this lab in their own research.

There is more information on the Skidaway Web site.

Sushi tasting a hit!

September 10, 2007

We had our informal sushi/sashimi tasting last Thursday evening, and it was a lot of fun.

Sushi PlateSome quick background — Professor Dick Lee wanted to see if there is any taste difference in sushi/sashimi made from black sea bass based on the diet the fish are fed. Dick raises black sea bass on a diet of juvenile tilapia. Does it taste better, worse or the same as food-pellet fed black sea bass or wild ocean black sea bass.

We put together a panel of self-professed sushi/sashimi lovers for an informal panel. Chef A.K. Tran of Sushi Time Towa restaurant here in Savannah prepared three trays of sushi which we identified only by A, B or C. Dick and research assistant Karrie Brinkley collected some subjective information on texture, smell, etc. However, a “show of hands” indicated the tilapia fed fish and the wild sea bass were tied for the favorite. The food pellet fed fish finished third. That was good news to Dick.

If you would like to see some pictures from the event, they are posted on the Skidaway Web site.

Skidaway Institute Seminar Series

September 4, 2007

Mike Sullivan writes:

The new superintendent of Gray’s Reef National Marine, George Sedberry, George Sedberrywill present the next program on the Skidaway Institute Seminar Series, on Tuesday, Sept 25, at 3:30 pm in the Skidaway Institute Library Auditorium. George will present a program on the “Charleston Bump” (That’s an underwater feature on the continental shelf — not a new dance.)

This will be George’s “introductory seminar” for the campus community and the general public.

More information is available on the Skidaway Institute Web site.

The Skidaway Institute Seminar Series presents periodic programs of interest to the scientific community and the general public. They are presented by our researchers and students and also various visiting scientists and students. If a visiting scientist is around for more than a couple of days, we usually ask them to present a seminar on whatever they are working on at the moment. As a non-scientist, I attend when I can and find many of them interesting. However, a warning is in order — many of the presentations are intended for working scientists. In those cases, they can be pretty tough to follow, unless you have a fairly strong background in science and its sometimes arcane vocabulary.

I don’t know at what level George will present his seminar on the 25th, but I suspect it won’t require a PhD to follow. Should be interesting.