Category: Top Posts

Is Marijuana Really a Gateway Drug?

By Dave Levitan | April 27, 2015 1:12 pm

marijuana

This article originally appeared on FactCheck.org.

Chris Christie recently said that marijuana is a “gateway drug” while arguing for enforcement of its federal status as an illegal substance. Though there are correlations between marijuana use and other drugs, there is no conclusive evidence that one actually causes the other. The science on this topic is far from settled.

The “gateway hypothesis” or theory refers to the idea that one substance — marijuana, in this case — leads users to subsequently use and/or abuse other drugs. If Christie’s point is simply that the use of marijuana tends to precede the use of other drugs, then he is correct — but that’s not the whole story.

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CATEGORIZED UNDER: Mind & Brain, Top Posts
MORE ABOUT: drugs & addiction

Why Astronomers Are Riveted By the Search for Nothing

By Carole Mundell, University of Bath | April 22, 2015 1:55 pm

supervoid

Astronomers have found evidence of a giant void that could be the largest known structure in the universe. The “supervoid” solves a controversial cosmic puzzle: it explains the origin of a large and anomalously cold region of the sky. However, future observations are needed to confirm the discovery and determine whether the void is unique.

The so-called cold spot can be seen in maps of the Cosmic Microwave Background (CMB), which is the radiation left over from the birth of the universe. It was first discovered by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) in 2004 and confirmed by ESA’s Planck Satellite. For more than a decade, astronomers have failed to explain its existence. But there has been no shortage of suggestions, with unproven and controversial theories being put forward including imprints of parallel universes, called the multiverse theory, and exotic physics in the early universe.

Now an international team of astronomers led by Istvan Szapudi of the Institute for Astronomy at The University of Hawaii at Manoa have found evidence for one of the theories: a supervoid, in which the density of galaxies is much lower than usual in the known universe.

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CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: cosmology

The Mystery of Breast Cancer’s Cause

By Richard Stevens, University of Connecticut | April 21, 2015 2:33 pm

mammogram

For most of the common cancers, a major cause has been identified: smoking causes 90% of lung cancer worldwide, hepatitis viruses cause most liver cancer, H pylori bacteria causes stomach cancer, human papillomavirus causes almost all cases of cervical cancer, colon cancer is largely explained by physical activity, diet and family history.

But for breast cancer, there is no smoking gun. It is almost unique among the common cancers of the world in that there is not a known major cause; there is no consensus among experts that proof of a major cause has been identified.

Yet, breast cancer is the most common form of cancer in women worldwide. The risk is not equally distributed around the globe, though. Women in North America and Northern Europe have long had five times the risk of women in Africa and Asia, though recently risk has been increasing fast in Africa and Asia for unknown reasons.

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CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: cancer

Could Small Amounts of Radiation Be Good For You? It’s Complicated.

By David Warmflash | April 6, 2015 11:07 am

operating room radiation

Exposure to high levels of ionizing radiation is extremely bad for human health. Witness the effects of acute radiation sickness suffered by early scientists studying radioactive elements, or by survivors of atomic bomb blasts. Witness the complex procedures through which doctors must shield cancer patients from radiation therapy, and the long-term complications of adult survivors of cancer who were treated with earlier technology. In light of all this, it’s clear that high doses of ionizing radiation are dangerous.

But the science is less clear when it comes to low dose radiation (LDR). Medical science, the nuclear industry, and government regulatory agencies generally take a play-it-safe approach when considering LDR. In recent years, however, an increasing number of researchers (though still firmly in the minority) have questioned the assumption that all radiation is bad – and have begun studying whether low doses might in fact aid in genetic repair, prevent tissue damage, and other benefits.

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CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: cancer, personal health

Real-Life Vampires Exist, and Researchers Are Studying Them

man silhouette

Vampires walk among us. But these people aren’t the stuff of nightmares – far from it actually. Just sit down for a drink with one of them and ask for yourself. That’s if you can find one. They aren’t necessarily looking to be found.

I’ve spent five years conducting ethnographic studies of the real vampires living in New Orleans and Buffalo. They are not easy to find, but when you do track them down, they can be quite friendly.

“Real vampires” is the collective term by which these people are known. They’re not “real” in the sense that they turn into bats and live forever but many do sport fangs and just as many live a primarily nocturnal existence. These are just some of the cultural markers real vampires adopt to express a shared (and, according to them, biological) essence – they need blood (human or animal) or psychic energy from donors in order to feel healthy.

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CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: sociology

We Get Infected By Other People’s Emotions – And That’s a Good Thing

By Michael Bond | March 25, 2015 12:24 pm

Image by pogonici/ Shutterstock

One day in October 2010, at a school in the Gaibandha district of northwest Bangladesh, a pupil noticed that the label on a packet of crackers she was eating had darkened. Fearing the crackers were contaminated – “the devil’s deed”, as she put it – she almost immediately fell ill, complaining of heartburn, headache and severe abdominal pain.

The condition quickly spread among her fellow pupils, and later to other schools in the area. Yet toxicologists could trace no contaminant, and all those affected were quickly discharged from the hospital after doctors found no trace of illness. The following week, investigators diagnosed “mass sociogenic illness,” otherwise known as mass hysteria. The children, it seemed, had developed their symptoms simply because they had seen their classmates succumb.

Mass hysteria is thought to be an extreme example of a phenomenon that affects us all day-to-day: emotional contagion. Short of living in hermitic isolation, it is hard to escape it; we are vulnerable to the moods and behaviors of others to an extraordinary degree.

Emotional contagion caused the failure of successive banks at the start of the Great Depression in the 1930s, when investors suffered a collective loss of faith in the ability of these institutions to pay out. It is the force behind fuel crises, health scares and the spread of public grief (for example in Britain after the death of Princess Diana in August 1997). It is the reason why you are more likely to be obese if you have obese friends, and depressed if you are living with a depressed roommate.

But emotional contagion is not all bad – far from it. The mechanism behind it – our tendency to mimic each other’s expressions and behaviors – is crucial to social interaction. Without it, anything beyond superficial communication would be impossible.

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CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: psychology

Six Things Facebook (Thinks It) Knows About Your Love Life

By Sarah Scoles | March 20, 2015 1:24 pm

facebook love

Facebook is watching you, collecting data on your every interaction and feeding it to their data scientists, who are hungry for correlations. But you know that, and you accept it as the price to live in the modern world (you probably even know that Facebook is manipulating you).

And Facebook’s data-science team is particularly interested in your romantic life. They’ve been watching you hook up and break up and, according to a recent presentation by Facebook employee Carlos Diuk, they’ve noticed a few things about you.

But, keep this in mind: these findings are the result of private and proprietary number-crunching, circumventing the normal procedures that let scientists call their output “science.” More on that in a minute.

So without further ado, six things Facebook thinks it knows about your love life:

1. Matchmakers have more friends than the people they’re introducing—73 percent more. (Matchmakers are people who introduce two of their friends, who later become a couple.) And those friends are more disconnected. Matchmakers’ networks include lots of people who aren’t friends with each other. The way I choose to interpret this: matchmakers have to diversify their interactions, so as not to overwhelm any single one with their aggressive extroversion and statements about who would be perrrrfect for whom. Read More

CATEGORIZED UNDER: Technology, Top Posts

Health Care for Sea Turtles Just Got a Shot in the Flipper

By Margo Pierce | March 19, 2015 2:35 pm

loggerhead

Nearly all species of sea turtles are globally endangered, plagued by habitat loss, hunting and illegal trade. About 230 rescue centers around the world do their best to treat sick turtles and return them to the wild. But their success rates are distressingly low, because sea turtles are especially difficult patients.

However, one rescue center has come up with a simple solution that could save many sea turtles’ lives: a special turtle IV system. Tests so far show that the approach drastically cuts turtle deaths, ultimately allowing more of the animals to be returned healthy to the wild.

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CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: animals

Humanity’s First Spacewalk, 50 Years Ago Today, Nearly Ended in Disaster

By Daniel Brown, Nottingham Trent University | March 18, 2015 4:57 pm
spacewalk2

NASA astronaut Nicholas Patrick on an EVA in 2010. Credit: NASA

It is 50 years since humans first encountered space – not Sputnik’s first orbit, nor Yuri Gagarin’s first spaceflight, but the first time a crew member stepped out from their spacecraft’s relative protection and immersed themselves in the cold, hostile emptiness of the vacuum.

On March 18, 1965, 30-year-old Russian cosmonaut Alexey Leonov completed a 12-minute spacewalk. This feat, and that of Gagarin and Sputnik before, was just one of the many achievements of the Soviet space program in the early years of the space race.

Leonov and others who followed him wore specially designed space suits, were tethered and later had helpful gadgets to move them around. Without the tether astronauts would have floated into empty space, with nothing to slow or change direction in frictionless space, with no rescue possible and only an inevitable death as their oxygen supply ran out. If this sounds daunting, imagine being the first ever to have faced this.

Only recently have we started to develop robotic equipment versatile and sensitive enough to carry out the complex tasks requiring fine motor skills taken for granted in any lab on Earth. Before then, astronauts had to walk in space and use these tools to repair satellites – such as the Hubble space telescope, which has given us the incredible science and images for the past 25 years. Spacewalks helped ensure we could walk on the moon, take samples and set up experiments.

Building the knowledge required to walk in space, and the robotic equipment to later help astronauts, also led toward the establishing of the US Skylab and Russian Mir orbital space labs, and their successor in the International Space Station (ISS).

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CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: space exploration

Archaeologists See and Smell the Past With Augmented Reality

By Carl Engelking | March 13, 2015 2:49 pm
Photo illustration by Discover. Credit: dezi/ Okyay/ Denys Prykhodov via Shutterstock

Photo illustration. Credit: dezi/ Okyay/ Denys Prykhodov via Shutterstock

Try to picture a time machine.

You probably envisioned a tricked-out DeLorean or, perhaps, a blue, spinning phone booth, right? But today, time travel isn’t so much about fast cars or alien technology as it is about tweaking our perception of reality. In fact, if you’re reading this on a tablet, you’re holding a time machine of sorts in your hands right now.

Of course, your iPad won’t actually transport you back in time, but it can serve as a window into another world. Imagine visiting the Parthenon, for example, and when you point your iPad toward the crumbled structure, you see the majestic building, but as it was thousands of years ago. You can even walk toward and around the structure, and so long as you’re peering through the tablet, it’s as if you were walking through the past.

This immersive experience, called augmented reality, has captivated archaeologist Stuart Eve, who is trying to change the way we learn history through the five senses. He’s working on augmented-reality technology that not only visually recreates ancient ruins, but also gives you a sense of what they smelled and sounded like.

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CATEGORIZED UNDER: Technology, Top Posts
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