14 Jan
Seven Myths About Arson
21 Jul
Preserving Insects in Hand Sanitizer
Credit: The Dragonfly Woman
Entomologists on Twitter got all excited last week when a tutorial for preserving insects in hand sanitizer was passed around. As a teacher and an entomologist who does a lot of aquatic insect outreach activities, I was very excited to learn about this method! Aquatic insects are typically stored in glass vials filled with alcohol, which unfortunately means the insects all sink to the bottom. It’s then really hard to position them so that you can see particular features. If you want a good look at the insect, you usually have to take it out of the vial and put it in a dish of alcohol. This all makes insects in vials hard to use in outreach activities. However, the hand sanitizer method featured photos of insects suspended in the middle of vials. No sinking to the bottom, no turning the vial over and over and over trying to get the insect flipped over just right to get a close look at a particular piece. They’re supposed to be durable too. I decided I had to try it – and it totally worked! READ ON FOR INSTRUCTIONS.
29 May
Human Intelligence and the Environment
HUMAN INTELLIGENCE AND THE ENVIRONMENT
Noam Chomsky
I’LL BEGIN with an interesting debate that took place some years ago between Carl Sagan, the well-known astrophysicist, and Ernst Mayr, the grand old man of American biology. They were debating the possibility of finding intelligent life elsewhere in the universe. And Sagan, speaking from the point of view of an astrophysicist, pointed out that there are innumerable planets just like ours. There is no reason they shouldn’t have developed intelligent life. Mayr, from the point of view of a biologist, argued that it’s very unlikely that we’ll find any. And his reason was, he said, we have exactly one example: Earth. So let’s take a look at Earth.
And what he basically argued is that intelligence is a kind of lethal mutation. And he had a good argument. He pointed out that if you take a look at biological success, which is essentially measured by how many of us are there, the organisms that do quite well are those that mutate very quickly, like bacteria, or those that are stuck in a fixed ecological niche, like beetles. They do fine. And they may survive the environmental crisis. But as you go up the scale of what we call intelligence, they are less and less successful. By the time you get to mammals, there are very few of them as compared with, say, insects. By the time you get to humans, the origin of humans may be 100,000 years ago, there is a very small group. We are kind of misled now because there are a lot of humans around, but that’s a matter of a few thousand years, which is meaningless from an evolutionary point of view. His argument was, you’re just not going to find intelligent life elsewhere, and you probably won’t find it here for very long either because it’s just a lethal mutation. He also added, a little bit ominously, that the average life span of a species, of the billions that have existed, is about 100,000 years, which is roughly the length of time that modern humans have existed.
With the environmental crisis, we’re now in a situation where we can decide whether Mayr was right or not. If nothing significant is done about it, and pretty quickly, then he will have been correct: human intelligence is indeed a lethal mutation. Maybe some humans will survive, but it will be scattered and nothing like a decent existence, and we’ll take a lot of the rest of the living world along with us. READ ON.
29 May
The Blind Man Who Taught Himself to See
The Blind Man Who Taught Himself To See
Written by Michael Finkel and Posted By MJ On March 1, 2011 at Men’s Journal
Photograph by Steve Pyke
Daniel Kish has been sightless since he was a year old. Yet he can mountain bike. And navigate the wilderness alone. And recognize a building as far away as 1,000 feet. How? The same way bats can see in the dark.
The first thing Daniel Kish does, when I pull up to his tidy gray bungalow in Long Beach, California, is make fun of my driving. “You’re going to leave it that far from the curb?” he asks. He’s standing on his stoop, a good 10 paces from my car. I glance behind me as I walk up to him. I am, indeed, parked about a foot and a half from the curb.
The second thing Kish does, in his living room a few minutes later, is remove his prosthetic eyeballs. He does this casually, like a person taking off a smudged pair of glasses. The prosthetics are thin convex shells, made of acrylic plastic, with light brown irises. A couple of times a day they need to be cleaned. “They get gummy,” he explains. Behind them is mostly scar tissue. He wipes them gently with a white cloth and places them back in.
Kish was born with an aggressive form of cancer called retinoblastoma, which attacks the retinas. To save his life, both of his eyes were removed by the time he was 13 months old. Since his infancy — Kish is now 44 — he has been adapting to his blindness in such remarkable ways that some people have wondered if he’s playing a grand practical joke. But Kish, I can confirm, is completely blind. READ ON.
29 May
Worm Can Regenerate From A Single Cell
WORM CAN REGENERATE FROM A SINGLE CELL
By Rebecca Boyle Posted 05.13.2011 at 4:23 pm at POPSCI.COM
One cell is all it takes to rebuild a complete, functioning flatworm, researchers have learned. The animals possess a special type of cell throughout their bodies, which shares some qualities with human embryonic stem cells. If scientists can find out how this special cell works, they could someday study ways to use the cells for human tissue regeneration.
The findings are the first time pluripotent stem cells have been found in an adult animal, according to researchers at MIT and the Howard Hughes Medical Institute.
Pluripotent stem cells have a unique ability to turn into any kind of cell, which is what makes them so valuable for disease research, tissue regeneration and other fields. But these cells are only found in embryos, or are induced in complex lab processes. Adults have stem cells, but they have greater specificity — blood stem cells can turn into any constituent part of the blood, and skin stem cells can turn into skin or hair, but they can’t turn into other cells like neurons, for instance.
Regenerating Flatworm This iamge shows the head region from an adult planarian (Schmidtea mediterranea). The creature was fixed 7 days after ionizing radiation treatment and contains a growing stem cell colony marked in red. Courtesy Peter Reddien
To figure this out, researchers led by Peter Reddien, Daniel Wagner and Irving Wang at MIT exposed the worms to ionizing radiation, robbing their cells of their ability to divide and regenerate. Without the ability to grow new cells, the animal would slowly die. The team killed off all the dividing cells except a rare group called cNeoblasts, and watched as those remaining cells divided to form large colonies of replacement cells.
Then they did something truly weird. Wang and Reddien harvested a single cNeoblast from one type of planarian. Then they gave a different kind of planarian, one that did not have its own neoblasts and couldn’t regenerate, a lethal dose of radiation. Its tissues started to die, from the head down toward its tail. Then they implanted the first worm’s neoblast into the tail of the second, dying worm.
They watched as the transplanted cNeoblast multiplied, differentiated and “ultimately replaced all the host’s tissues,” according to a news release from the Whitehead Institute for Biomedical Research. Descendants of the single neoblast cell differentiated into neuronal, intestinal and other adult cell types, taking over the jobs of the host’s dying cells. The newly restored worm was an exact genetic copy of the cNeoblast donor. All this from one single cell.
The results were published in today’s issue of the journal Science.
In a news release, Wagner said planarians have already solved the problem of regeneration, and scientists want to determine how it works.
“One day, we’ll examine what are the key differences between what’s possible in this animal and what’s possible in a mouse or a person,” he said.
19 May
Dede Koswara: “The Tree Man”
Copyright: Reuters
- Please read the article, ‘The Tree Man’ handout. The article was taken from the book ‘Medical Mysteries.’
- The warts that cover Dede’s body are caused by a rare, autosomal recessive, genetic disorder called Epidermodysplasia verruciformis. Respond to the following questions:
- What are warts? What causes them? How are they typically treated?
- What makes Dede’s case so unique? The warts affect the integumentary system but how is the immune system involved?
- If you could ask Dede or his doctor 5 questions, what would they be? List them.
19 Apr
The Girl in the Window
The Girl in the Window
Lane DeGregory, Times Staff Writer, St. Petersburg Times
Posted: Jul 31, 2008 04:35 PM
Dani, 9, has a new family now, and a new chance at life thanks to her brother William, 10, and parents Diane and Bernie Lierow.
Part One: The Feral Child
PLANT CITY — The family had lived in the rundown rental house for almost three years when someone first saw a child’s face in the window.
A little girl, pale, with dark eyes, lifted a dirty blanket above the broken glass and peered out, one neighbor remembered.
Everyone knew a woman lived in the house with her boyfriend and two adult sons. But they had never seen a child there, had never noticed anyone playing in the overgrown yard.
The girl looked young, 5 or 6, and thin. Too thin. Her cheeks seemed sunken; her eyes were lost.
The child stared into the square of sunlight, then slipped away.
Months went by. The face never reappeared.
Just before noon on July 13, 2005, a Plant City police car pulled up outside that shattered window. Two officers went into the house — and one stumbled back out.
Clutching his stomach, the rookie retched in the weeds. READ ON.
