Category: Science

Experiences with Dropsy in Goldfish

Posted on September 16, 2004 by ellen

Dropsy is one of the worst diseases goldfish can come down with. It’s usually fatal. I hope this description of one goldfish that survived a bout of dropsy will help someone to save their fish.

Fish are said to have the disease “dropsy” when they swell up and their scales stand out all over like a pinecone. As JoAnn the Goldfish Guru says, “Dropsy is a SYMPTOM of other problem(s) with the fish. Dropsy can be due to problems with the environment (water quality, temperature shock, alkalinity), parasites, bacteria or virus.” Dropsy is apparently caused by bacterial infections and kidney failure.

Eggdrop in a happy moment. He has never been able to swim correctly, so he uses the bubblers to get around.

Winning the war on Greenwater Algae

Posted on March 1, 2004 by ellen

For about 4 months, I fought a war against greenwater algae in our big aquarium, home of our pet oscars. If you don’t know what an oscar is, they are the most cantankerous, petulant, opinionated tropical fish ever created and they make great pets. They are members of the cichlid family, and are extremely smart, even trainable.

My oscar, Galadrial, showing her friendlier side

But this article is not about oscars. It’s about their unwanted tankmate: greenwater algae. This algae was so thick I couldn’t even see the fish! They would swim in and out of the green gloom. There are those who will tell you that greenwater algae is good for your fish, and indeed, it may be. But it doesn’t look very good in your living room, and I wanted to be able to see the oscars! So I determined to rid my tank of the ugly, smelly stuff.

This looks a lot like my tank did. Try to imagine 120 gallons of this algae soup in your living room!

photo © Charles Yu, from an FAQ article on algae by George Booth

How we die

Posted on February 28, 2004 by ellen

Remember all those sci-fi stories where people learn the date and cause of their own death? “Life-Line” by Robert Heinlein is one that pops to mind, but there are many others.

Well, you may not be able to tell when you will die, but you can make a pretty good guess what you may die of, based on age-related statistics published by the CDC. The latest final statistics are for 2001, so this is based on those numbers. The complete report can be found here: Leading causes of death for 2001

Note for clarity: percentages given in the samples
below are the percent of the total people in a given age group
that actually died in 2001, not the percentage of all people
in that age group.

Note 2 : 2001 data includes the 3028 deaths they
were certain of by the publish date of the statistics caused by the terror
attacks on September 11. Of these, 2,922 are classified as homicides and 4
as suicides. Only residents of the United States are counted in these statistics.

Why you should be afraid of catching the Flu

Posted on January 15, 2004 by ellen

Having recently recovered from a bad case of the flu, I got to wondering why they can’t just make a vaccine to take care of it once and for all, like the measles?

It turns out the flu virus is unique in its ability to mutate and adapt, making it impossible to use a single vaccine to combat it. The situation is complicated by the fact that animals, both wild and domestic, are a sort of “mixing bowl” in which new strains of the virus are created.

The variation in the virulence of the flu is apparently due to the varying degrees to which our immune system recognizes the two types of proteins on the surface of the virus -hemagglutinin (H) and neuraminidase (N).

The virus strain is said to undergo “drift” when there are minor changes in the two proteins. This is what happens most years. But sometimes it undergoes a more major change, called “shift,” which is due to reassortment of the viral genes, often when it is mixed with another strain in animals. This is a really bad thing because it means humans will have no antibodies that recognize the new strain, and so no immunity to it.

This Year’s Flu Vaccine

Posted on December 20, 2003 by ellen

Well, unlike previous years, I can officially say that this year’s flu vaccine did not work on me. I had the shot about 5 weeks ago, and yesterday came down with a full-blown case of

Taming viruses to control introduced pest animals

Posted on October 3, 2003 by ellen

I found this interesting.

Australia has one of the most active research groups in the world in this area, since the Australian environment suffers from many pest animals that were introduced and have no natural predators.

New Scientist reports that Australian researchers have created a highly infectious rabbit virus (myxoma) that could wipe out the country’s rabbit pests by making them sterile. Infected female rabbits produce antibodies against their own eggs, a process called immunocontraception. The team has already applied for permission to carry out field trials with a similar virus that makes European mice infertile.