All posts filed under: Science

Science

Antidepressants Cause Weight Gain?

Antidepressant medications can be hugely helpful—even life-saving—for those who suffer from certain types of mood disorders. But they can also sometimes cause people to gain a significant amount of weight. Not so helpful. Studies indicate that about 25% of the people who take antidepressant medications report significant weight gain. This is seen more commonly in those who take these drugs for six months or more, but it’s not uncommon for people to report gaining 8-10 pounds within just a few weeks of starting drug therapy. Either way, it’s a bummer. You can easily imagine that frustration and negative feelings about weight gain could cancel out whatever mood elevating benefits the drugs are delivering! Are Antidepressants Worth it? There’s also some controversy over how much these drugs are really helping the millions of people who are taking them. My friend Dr. Ellen Hendricksen of the Savvy Psychologist podcast reviewed some of the research on this in a recent episode of the Savvy Psychologist. According to Ellen, studies suggest that a lot of people get little to …

How build a colony on an alien world?

If the human race is to survive in the long-run, we will probably have to colonise other planets. Whether we make the Earth uninhabitable ourselves or it simply reaches the natural end of its ability to support life, one day we will have to look for a new home. Hollywood films such as The Martian and Interstellar give us a glimpse of what may be in store for us. Mars is certainly the most habitable destination in our solar system, but there are thousands of exoplanets orbiting other stars that could be a replacement for our Earth. So what technology will we need to make this possible? We effectively already have one space colony, the International Space Station (ISS). But it is only 350km away from Earth and relies on a continuous resupply of resources for its crew of six. Much of the technology developed for the ISS, such as radiation shielding, water and air recycling, solar power collection, is certainly transferable to future space settlements. However, a permanent space colony on the surface of …

Wormhole Allows Information to Escape Black Holes

In 1985, when Carl Sagan was writing the novel Contact, he needed to quickly transport his protagonist Dr. Ellie Arroway from Earth to the star Vega. He had her enter a black hole and exit light-years away, but he didn’t know if this made any sense. The Cornell University astrophysicist and television star consulted his friend Kip Thorne, a black hole expert at the California Institute of Technology (who won a Nobel Prize earlier this month). Thorne knew that Arroway couldn’t get to Vega via a black hole, which is thought to trap and destroy anything that falls in. But it occurred to him that she might make use of another kind of hole consistent with Albert Einstein’s general theory of relativity: a tunnel or “wormhole” connecting distant locations in space-time. While the simplest theoretical wormholes immediately collapse and disappear before anything can get through, Thorne wondered whether it might be possible for an “infinitely advanced” sci-fi civilization to stabilize a wormhole long enough for something or someone to traverse it. He figured out that …

How to help Vaccine Doubters

We are in the golden age for vaccines. We have dozens of highly effective vaccines licensed for infectious disease, promising new technologies contributing to massive advancement of vaccine development, and several promising vaccines on the horizon. Unfortunately, vaccines have been a victim of their own success. With the drastic reduction of once-devastating diseases like whooping cough and measles, it seems like some parents think that the vaccines themselves are the new danger. But the threat isn’t gone; it’s been kept at bay by vaccinations. With clusters of vaccine-hesitant individuals especially worrisome, we need to find effective ways to convince people that the true danger is still disease. Concerns about the chemical components of vaccines, government mandates of vaccinations for school entry, and “Big Pharma” pushing vaccination seem unchanged when facts countering these claims are presented. Most of the existing research focuses on providing education or addressing parental vaccine attitudes, but rarely addresses the values people hold. We know that a host of factors influence how people retain and use facts in their decision-making, and most …

Can you weigh Cloud?

Have you ever wondered how much a cloud weighs? Even though a cloud seems to float in air, both the air and the cloud have mass and weight. Clouds float in the sky because they are less dense than air, yet it turns out they weigh a lot. How much? About a million pounds! Here’s how the calculation works: Finding the Weight of a Cloud Clouds form when the temperature becomes too cold for the air to hold water vapor. The vapor condenses into tiny droplets. Scientists have measured the density of a cumulus cloud at about 0.5 grams per cubic meter. Cumulus clouds are fluffy white clouds, but the density of clouds depends on their type. Lacy cirrus clouds may have a lower density, while rain-bearing cumulonimbus clouds may be more dense. A cumulus cloud is a good starting point for a calculation, though, because these clouds have a fairly easy-to-measure shape and size. How do you measure a cloud? One way is to drive straight across its shadow when the sun is overhead at …

China tests prototype air cleaner

 A 60-metre-high chimney stands among a sea of high-rise buildings in one of China’s most polluted cities. But instead of adding to Xian’s smog, this chimney is helping to clear the air. The outdoor air-purifying system, powered by the Sun, filters out noxious particles and billows clean air into the skies. Chinese scientists who designed the prototype say that the system could significantly cut pollution in urban areas in China and elsewhere. The technology has excited and intrigued researchers — especially in China, where air pollution is a daily challenge. Early results, which are yet to be published, are promising, says the project’s leader Cao Junji, a chemist at the Chinese Academy of Sciences’ Key Laboratory of Aerosol Chemistry and Physics in Xian in central China. “This is certainly a very interesting idea,” says Donald Wuebbles, an atmospheric scientist at the University of Illinois at Urbana-Champaign, who has heard about the system but not seen it in action. “I am not aware of anyone else doing a project like this one.” The prototype, built with …

How fast can humans run?

How fast can humans run? The fastest person clocked on our planet today is the Jamaican athlete Usain Bolt, who ran the 100 meter sprint at the 2008 Summer Olympics in Beijing in a world record of 9.58 seconds, which works out to be about 37.6 kilometers per hour or 23.4 miles per hour. For a brief period during that sprint, Bolt reached an astounding 12.3 meters per second (27.51 mph or 44.28 kph).nd (27.51 mph or 44.28 kph). As a physical activity, running is qualitatively different from walking. In running, a person’s legs flex and the muscles are forcibly stretched and then contracted during acceleration. The potential gravitational energy and the kinetic energy available in a person’s body changes as the center of mass in the body changes. That is thought to be because of the alternating release and absorption of energy in the muscles. What Makes an Elite Runner? Scholars believe that the fastest runners, the elite sprinters, are those who run economically, meaning that they use a low amount of energy per unit …

Introduction to Holography skepticsociety.co.uk

Introduction to Holography

If you’re carrying money, a drivers license, or credit cards, you’re carrying around holograms. The dove hologram on a Visa card may be the most familiar. The rainbow-colored bird changes colors and appears to move as you tilt the card. Unlike a bird in a traditional photograph, a holographic bird is a three-dimensional image. Holograms are formed by interference of light beams from a laser. HOW LASERS MAKE HOLOGRAMS Holograms are made using lasers because laser light is “coherent.” What this means is that all of the photons of laser light have exactly the same frequency and phase difference. Splitting a laser beam produces two beams that are the same color as each other (monochromatic). In contrast, regular white light consists of many different frequencies of light. When white light is diffracted, the frequencies split to form a rainbow of colors. In conventional photography, the light reflected off an object strikes a strip of film that contains a chemical (i.e., silver bromide) that reacts to light. This produces a two-dimensional representation of the subject. A …

How animals taking communal decisions

Today we opt for ballot boxes but humans have used numerous ways of voting to have their say throughout history. However, we’re not the only ones living (or seeking to live) in a democratic society: a new study has suggested that African wild dogs vote to make group decisions. A new study has found that these dogs sneeze to decide when to stop resting and start hunting. Researchers found that the rates of sneezing during greeting rallies – which happen after, or sometimes during, a rest period – affect the likelihood of the pack departing to hunt, rather than going back to sleep. If dominant individuals start the rally it is much more likely to result in a hunt, and only two or three sneezes are required to get the pack started. But if a subordinate individual wishes to start a hunt, they have to sneeze a lot more – around ten times – to get the pack to move off. The researchers think that this sneezing is the pack members voting on when to …

Affects of some of the most addictive substances

Affects of some of the most addictive substances

What are the most addictive drugs? This question seems simple, but the answer depends on whom you ask. From the points of view of different researchers, the potential for a drug to be addictive can be judged in terms of the harm it causes, the street value of the drug, the extent to which the drug activates the brain’s dopamine system, how pleasurable people report the drug to be, the degree to which the drug causes withdrawal symptoms, and how easily a person trying the drug will become hooked. There are other facets to measuring the addictive potential of a drug, too, and there are even researchers who argue that no drug is always addictive. Given the varied view of researchers, then, one way of ranking addictive drugs is to ask expert panels. In 2007, David Nutt and his colleagues asked addiction experts to do exactly that – with some interesting findings. 1. Heroin Nutt et al.’s experts ranked heroin as the most addictive drug, giving it a score of 3 out of a maximum …