Not a Simple Thing

By the middle of 2013, there were some 500 places in the world's oceans, seas, lakes, and estuaries where even a fish could drown. These so-called dead zones, hypoxic areas where too little oxygen is dissolved in the water to support conventional levels of marine life, present a growing problem to ecosystems and economies all over the planet.

When it comes to our daily fare, the only thing that doctors, dietitians, and government experts seem to agree on is the shape of the United States Department of Agriculture (USDA) Food Guide Pyramid. This familiar triangle, found on the packaging of most foods we consume, sends a simple message: eat generous amounts of the foods found at the bottom of the pyramid, and eat sparingly of those found at the tip. The controversy surrounding the food pyramid turns on which foods belong where and in what quantities. Since the U.S. government adopted the food pyramid back in 1992, research on nutrition has evolved, making some believe that the current guidelines are obsolete. For example, while the recommendation that we consume large servings of bread, cereal, pasta, and rice, found at the bottom of the pyramid, sounds like good advice, there is no distinction made between "refined" foods, like white bread and white rice, and "unrefined" foods, like whole-grain breads and...

As the world’s power requirements grow, so do concerns over environmental pollution caused by nuclear- and fossil-fuel-fired electric generating plants. Air pollution, caused by the emission of nitrogen oxides, sulfur oxides, and suspended particulate matter; water pollution, coming from oil spills and radioactive waste; thermal pollution, resulting from the discharge of waste heat; and noise pollution, caused by equipment operation---all have a major impact on the environment and the dynamics of the ecology. The increased use of alternative, “green” sources of electric power production could assist in reducing some of these hazards. Geothermal power plants, for example, use the earth’s interior heat as a power source; they are economical to build and operate and produce no air pollution or radiation. Solar cells, which convert solar energy to electrical energy, cause no environmental pollution; they are very expensive sources of power but are useful where connection to a utility power...

Until the last few hundred years, the sudden appearance of a bright comet was interpreted as a sign of danger, war, or famine. Such was the case in the year 1066, when a comet now known as Halley's Comet appeared before the Battle of Hastings (which led to the Norman Conquest of England); its appearance was deemed significant enough to be depicted in the Bayeux Tapestry. Comets were thought to be atmospheric phenomena until Danish astronomer Tycho Brahe demonstrated that the great comet of 1577 was appreciably more distant than the moon. A century later Isaac Newton was asked by his fellow Royal Society members, physicist Robert Hooke and astronomer Edmond Halley, to look into the problem of planetary motion with which they were struggling unsuccessfully. Newton showed (and later described in Principia) that his laws of motion and gravitation applied to comets as well as planets and other objects in the solar system. Filled with "joy and amazement" (in his own words), H...

The U.S. Food and Drug Administration (FDA) has advised that selective serotonin reuptake inhibitors (SSRIs), sold under trade names such as Prozac, Paxil, Zoloft, and Celexa, must carry a warning that their use in adolescents may pose a risk by leading to an increase in suicidal thoughts. Although many young people have benefited from the use of SSRIs, there also are indications that these drugs can lead to self-destructive behavior in young adults. It is important to know how and why the FDA reached the decision to add an advisory warning to prescription antidepressant drugs; but first the causes of depression and how SSRIs work to alleviate it must be examined. One could say that it all begins with serotonin, a mood-regulating neurotransmitter. Defined as substances that carry neural impulses across a synapse (a space between two neurons), neurotransmitters are essential to the electrochemical transmission of messages through the nervous system and within the brain. Insufficient amo...

Thomas Edison is widely known in the United States as perhaps the greatest inventor of all time: the creator of the light bulb, the phonograph, and the motion picture. However, in the battle to provide electrical power across America, he came out the loser to the designs of a Croatian immigrant named Nikola Tesla, a man little known outside the fields of science and engineering. While studying engineering as a young man in Graz, Austria, during the late 1800s, Tesla realized the limitations of direct current (DC) as a method of transmitting electricity over distance. Invented by Edison in 1879, DC was quickly put to use, providing power to buildings in New York City and other urban centers, although its limitations soon became apparent. DC is so named because the current travels in only one direction. Because of the low voltage involved and the resistance in the wires through which the electricity is sent, it is nearly impossible to transmit DC over long distances. Consequently, genera...

Despite literally millions of books in print focusing on the concept of robots---indeed, an entire subgenre of science fiction is dedicated to these artificial automatons---precious few robotics enthusiasts are aware of the 1921 stage play R.U.R., the work of fiction that first popularized the word robot. Written in 1920 by the Czech playwright and novelist Karel Capek, R.U.R. is today best known for its connection with the etymology of the word robot, but the play also gave the word, and the world, our larger robotic legacy. R.U.R. stands for Rossum's Universal Robots, the fictional corporation at the center of the play that has cornered the world's economic markets, thanks to its exclusive, secret process for mass-producing cheap artificial laborers. The term robot is derived from such Czech words as robota, meaning "forced labor," which is precisely the sort of work that the robots of the play perform, that is, until they rebel against their human masters and conqu...