Vanilla is a product of Lussumo:Documentation and Support.
161 to 180 of 223
Scientists at UC Santa Barbara have discovered a caste of genetically identical "warrior worms" -- members of a parasitic fluke species that invades the California horn snail.The findings are reported in the early online version of the Proceedings of the Royal Society B."We have discovered flatworms in colonies with vicious, killer morphs defending the colony," said Armand M. Kuris, professor of zoology, in the Department of Ecology, Evolution and Marine Biology. "These flukes have a strongly developed social organization, much like some insects, mammals and birds." The tiny warrior worms are only a couple of millimeters in length, yet they are powerful thanks to relatively large mouths.These worms form colonies in snails. Reproductive worms and soldier worms cooperate to grow and defend their colony within the snail. These two types of individuals look and behave differently, explained first author Ryan F. Hechinger, assistant research biologist with UCSB's Marine Science Institute. The warrior worms attack other invasive parasites trying to invade the snail.[...]These colonies also act like an immune system, defending the body of the snail from other fluke infections, said second author Alan C. Wood, a marine science lab manager at UCSB. The soldiers behave like white blood cells; they attack other unrelated flukes, biting and killing them.These flukes with soldier castes may also have a biomedical application. They might be used in the biological control of major human parasitic diseases such as blood flukes. There are 200 million cases of blood fluke diseases worldwide, said Kuris. The soldier worms might eliminate infections from forming in the snail hosts, preventing infections in humans. Liver flukes might also be controlled.
Perhaps human tears contained a chemical signal too, Sobel thought. So he asked six women to watch triple-hanky chick flicks such as "My Sister's Keeper" and let their tears trickle into a test tube.
Satirist Stephen Colbert envisions his “Colbert Nation” mentally marching in lockstep with his special brand of patriotism. But scientists have done him one better, by creating tiny worm-bots completely under their control.Rather than comedic persuasion, these scientists are using a dot of laser light. With it they can make a worm turn left, freeze or lay an egg. The researchers report their work online Jan. 16 in Nature Methods.The new system, named CoLBeRT for “Controlling Locomotion and Behavior in Real Time,” doesn’t just create a mindless zombie-worm, though. It gives scientists the ability to pick apart complicated behaviors on a cell-by-cell basis.[...] Transparent and small, the nematode Caenorhabditis elegans is particularly amenable to light-based mind control. Another benefit of the worm is that researchers know the precise location of all 302 of its nerve cells. But until now, there wasn’t a good way to study each cell by itself, especially in a wriggling animal.“This tool allows us to go in and poke and prod at those neurons in an animal as it’s moving, and see exactly what each neuron does,” says study co-author Andrew Leifer of Harvard University.The system is based on the emerging field of optogenetics, in which light is used to turn cells on or off. Leifer and his colleagues genetically engineered light-responsive molecules into particular groups of cells in the worm.Then, a computer program that the team developed figures out where in the microscope’s field of view a target cell is. Once the cell is pinpointed, the program directs lasers so that a tiny beam of light hits the cell.