Researchers have known for some time that the food and drink we all consume contains arsenic.
Should we be concerned? Aren’t we protected by federal regulations? Actually, no – we are not. In the US, as in many countries, the government regulates the concentration of arsenic in drinking water, but does not regulate the concentration of arsenic in any other drink or food. We have a mercury-in-food regulation; why don’t we have an arsenic-in-food regulation?
One important difference is that all of the compounds of mercury we find in food are equally toxic. This is not the case for arsenic. Although we normally think of arsenic compounds as potentially harmful, most of the arsenic we eat is harmless. Seafood, which contains by far the highest concentrations of arsenic, delivers it as arsenobetaine, an organic chemical containing arsenic that is innocuous to us humans.
How then should arsenic in food be regulated? To do that well, we need to develop better ways to determine the amounts of arsenic and other chemicals in our foods.
Volcanic eruptions produce some stunning scenes, the eruption of the Calbuco volcano in Chile being one recent example. Calbuco fits the stereotypical image of a volcano: a large, angry mountain rising up into the sky, the same kind of volcano as Mount St. Helens or Mount Fuji. But some of the world’s most powerful volcanoes – and the second most common – are hidden from sight and can unexpectedly detonate with the force of a nuclear bomb.
Maar volcanoes are strange: they are often invisible for much of their life, before suddenly appearing in enormous explosions. They give no warning of their impending destruction. When they do erupt in a cataclysm of fire and noise, they do not rise above the ground, but instead leave a hole similar to large meteorite impact craters.
The 1886 eruption of Rotomahana on the north island of New Zealand was one such eruption. With the only warning coming from a small, insignificant earthquake in the region beforehand, a maar volcano-forming eruption suddenly occurred overnight. The resulting heat blasts and descending hot ash and lava bombs killed at least 150 people.
The recent earthquake in Nepal demonstrated yet again how difficult it is to reliably predict natural disasters. While we have a good knowledge of the various earthquakes zones on the planet, we have no way of knowing exactly when a big quake like the 7.8-magnitude event in Nepal will happen.
But we know that many animals seem able to sense the onset of such events. We could use powerful computers to monitor herds of animals and make use of their natural instincts to provide forewarning of natural disasters.
Immediately before an earthquake, herds of animals often start to behave strangely – for example suddenly leaving their homes to seek shelter. This could be because they detect small, fast-traveling waves or because they sense chemical changes in ground water from an impending earthquake.
Although there are possibilities here, we certainly need more studies – because it’s difficult to find statistically significant links between unusual animal behavior and impending disasters. This is because natural disasters occur relatively rarely and it’s hard to reliably interpret animal behavior after the fact. In fact, this uncertainty was quoted by the Chinese government after reports that zoo animals behaved strangely before the Wenchuan earthquake a few years ago.
Technology enhanced with artificial intelligence is all around us. You might have a robot vacuum cleaner ready to leap into action to clean up your kitchen floor. Maybe you asked Siri or Google—two apps using decent examples of artificial intelligence technology—for some help already today. The continual enhancement of AI and its increased presence in our world speak to achievements in science and engineering that have tremendous potential to improve our lives.
Or destroy us.
At least, that’s the central theme in the new Avengers: Age of Ultron movie with headliner Ultron serving as exemplar for AI gone bad. It’s a timely theme, given some high-profile AI concerns lately. But is it something we should be worried about?
Let’s wallow in semen a little while longer, shall we? We have already seen that, even in humans, there is more to this substance than meets the eye. It contains proteins that, when mixed together, can forge a mating plug. It also contains sugars as sperm fuel, proteins that protect the sperm cells from the acidic vaginal environment, zinc that keeps the sperm’s DNA in good shape, and chemical compounds that prevent the sperm cells from becoming overenthusiastic prematurely.
But this list of ingredients is just the tip of the iceberg. Human ejaculates are home to hundreds of different proteins (which in certain women cause a kind of “sperm hay fever,” an allergic reaction to semen). And those are not trace amounts either; most of them occur in considerable concentrations, so they must be doing something important—we just don’t know what. Even in the ejaculate of the lowly banana fly Drosophila melanogaster, researchers have identified no fewer than 133 different kinds of proteins. One hundred and thirty-three! And this excludes the many proteins that are in the sperm cells themselves. These 133 are all produced by the banana fly version of the prostate, which releases them into the liquid portion of the semen.
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.
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.
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.
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.
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.