Wednesday, 19 June, 2013

First of all, it’s important to remember that many people don’t enjoy these experiences, said Jack Nitschke, a UW-Madison professor of psychiatry and psychology. But those who do may be seeking thrills provided by the amygdala, a brain region that controls our emotional responses to salient objects and events. The amygdala kicks in when we [...]

The moment a knife slices through apple—spilling the contents of apple cells along the surface of the cut, and allowing everything to mix—a reaction begins. In particular, an enzyme known as polyphenol oxidase that had been held in check is loosed. Almost immediately, it begins altering polyphenols, a group of health-promoting chemicals with antioxidant activity [...]

It depends on the kind of lifestyle those people enjoy, says Lisa Naughton, a UW-Madison professor of geography and environmental studies. The late 18th century English economist Thomas Malthus – one of the first to express concern about overpopulation – observed that there should be no more people in a country than can “daily enjoy [...]

When the Large Hadron Collider starts running this summer near Geneva, Switzerland, some physicists have predicted that some of its high-energy proton collisions could produce microscopic black holes. Concerned about the ramifications of such black holes, two men filed a lawsuit in March in Hawaii contending that safety concerns have been inadequately addressed at the [...]

Today, ethanol is a fuel additive used to replace or decrease the need for fossil fuels in trucks, automobiles and other engines. Most of this ethanol comes from the sugars within corn kernels, but the search for other sources of sugar is under way. “The likely candidate? Ethanol made from sugars in cellulose, or ‘grassoline,’ [...]

That depends on conditions. “Today’s cars are designed to be very aerodynamic,” says Glenn Bower, a senior scientist at the Engine Research Center at UW-Madison. “They ‘cut’ through the air at moderate speeds. At lower speed, stopping and starting dominate the vehicle’s energy consumption, while at highway speed (45 to 65 mph) most of the [...]

“It’s true. There’s always one in every group,” says UW-Madison entomology professor and mosquito expert Susan Paskewitz. That’s not to say mosquitoes target certain people because they’re tastier or have higher quality blood. Rather, it’s all about how easy you are to locate. “The main things are how you smell and how hot you are,” [...]

Mark Renz, Extension weed scientist at UW-Madison’s Department of Agronomy, says that varying environmental conditions ensure that virtually all plants, including dandelions, have some good years and some poor ones. However, dandelions may be a special case, he says, since they seem perfectly suited to conditions in this area. “I’ve only been in Wisconsin for [...]

Following Sigmund Freud, many people used to believe dreams were a way of dealing with thoughts and issues that were too painful or bizarre to confront during waking life. From this idea, the entire field of dream interpretation emerged. Most scientists no longer believe this, though. “The truth is, we don’t really know why we [...]

Tornadoes can happen whenever atmospheric conditions are suitable, says Steve Ackerman, professor of atmospheric science at UW-Madison. Over the years, Wisconsin has had at least one tornado in every month except February. “To get any severe weather, we need really warm, moist air near the ground, and cool air aloft, which is typical of the [...]

One fact we know from childhood: every snowflake is unique. Isn’t it? UW-Madison’s snowflake expert, meteorology professor Pao Wang, gently delivered the grim news: “Not really. I think the saying is more or less a picturesque way of saying that there are so many varieties of snowflakes, thousands of different kinds.” Wang studies how snow [...]

It’s all about phospholipids, says John Moore, director of the Institute for Chemical Education at UW-Madison. Not a flavor guy himself, he poked around and learned that these oily, fatty materials affect receptors that sense the bitter flavor. Detergents in toothpaste, including sodium laurel sulfate, break up phospholipids that are normally on the tongue, Moore [...]

The colors of the sunset result from a phenomenon called scattering, says Steven Ackerman, professor of meteorology at UW-Madison. Molecules and small particles in the atmosphere change the direction of light rays, causing them to scatter. Scattering affects the color of light coming from the sky, but the details are determined by the wavelength of [...]

Many of the colors we see in fall are always present, but normally they’re hidden from view, says UW-Madison Arboretum native plant gardener Susan Carpenter. The leaves of trees and other plants contain three main pigments: carotene, anthocyanin, and the photosynthetic pigment, chlorophyll, which captures the sun’s energy to make food for plants. As the [...]

If a piece of toast fell on the floor, would you pick it up and eat it? You probably would if you believe in the 5-second rule, which suggests that your spilled breakfast stays germ-free as long as you snatch it up in five seconds. But while the 5-second rule remains a popular rule of [...]