Get Lost in Mega-Tunnels Dug by South American Megafauna

By Andrew Jenner | March 28, 2017 1:39 pm
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Looking into a large paleoburrow in Brazil. (Courtesy: Heinrich Frank)

It was in 2010 that Amilcar Adamy first investigated rumors of an impressive cave in southern Brazil.

A geologist with the Brazilian Geological Survey (known by its Portuguese acronym, CPRM) Adamy was at the time working on a general survey of the Amazonian state of Rondonia. After asking around, he eventually found his way to a gaping hole on a wooded slope a few miles north of the Bolivian border.

Unable to contact the landowner, Adamy couldn’t study the cave in detail during that first encounter. But a preliminary inspection revealed it wasn’t the work of any natural geological process. He’d been in other caves nearby, formed by water within the same geology underlying this particular hillside. Those caves looked nothing like this large, round passage with a smooth floor.

“I’d never seen anything like it before,” said Adamy, who resolved to return for a closer look some day. “It really grabbed my attention. It didn’t look natural.”

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

Revisited: The Regenerative Power of Pig Guts

By Adam Piore | March 27, 2017 3:09 pm
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(Credit: AVA Bitter/Shutterstock)

Bioengineers have made great strides harnessing the body’s ability to start over, whether regenerating heart tissue and bones, or using stem cells to regrow fingertips. Still, much of regenerative medicine’s promise remains inside the laboratory—or at least that was what I thought when I began reporting for The Body Builders: Inside the Science of the Engineered Human.

Some clinicians, like Dr. Eugenio Rodriguez, aren’t waiting for trials to be completed to help patients. Instead, they are already adding regenerative technologies to their medical toolboxes, and using them to save human limbs. Years ago down in Delray Beach, Florida, Rodriguez, a trauma surgeon, caused a bit of a sensation after exploring the regenerative powers of pig guts. Read More

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

Soaking in a Hot Bath Yields Benefits Similar to Exercise

By Steve Faulkner, Loughborough University | March 21, 2017 11:17 am

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Many cultures swear by the benefits of a hot bath. But only recently has science began to understand how passive heating (as opposed to getting hot and sweaty from exercise) improves health. The Conversation

At Loughborough University we investigated the effect of a hot bath on blood sugar control (an important measure of metabolic fitness) and on energy expended (number of calories burned). We recruited 14 men to take part in the study. They were assigned to an hour-long soak in a hot bath (40˚C) or an hour of cycling. The activities were designed to cause a 1˚C rise in core body temperature over the course of one hour. Read More

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

Phosphorus Is Vital for Life, and We’re Running Low

By Vera Thoss, Bangor University | March 15, 2017 11:05 am
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A farmer sprays field with a nitrogen, phosphorus, potassium fertilizer. (Credit: oticki/Shutterstock)

All life needs phosphorus and agricultural yields are improved when phosphorus is added to growing plants and the diet of livestock. Consequently, it is used globally as a fertilizer – and plays an important role in meeting the world’s food requirements.

In order for us to add it, however, we first need to extract it from a concentrated form – and the supply comes almost exclusively from phosphate mines in Morocco (with far smaller quantities coming from China, the US, Jordan and South Africa). Within Morocco, most of the mines are in Western Sahara, a former Spanish colony which was annexed by Morocco in 1975.

The fact that more than 70 percent of the global supply comes from this single location is problematic, especially as scientists are warning that we are approaching “peak phosphorus”, the point at which demand begins to outstrip supply and intensive agriculture cannot continue to provide current yields. In the worst case scenario, mineable reserves could be exhausted within as little as 35 years.

So what is going on – and how worried should be?

Here be phosphorus. (Credit: Shutterstock)

Natural Limits

In nature, phosphorus only exists bound to oxygen, which is called phosphate. It is in this form that it is mined. Chemists can remove the oxygens bound to it to get elemental white phosphorus, which glows in the dark, but it is so unstable that it spontaneously ignites on exposure to air.

Phosphate easily diffuses through soil or water and can be taken up by cells. When phosphate meets free calcium or iron, they combine to give highly insoluble salts.

In the first half of the 19th century, Justus von Liebig popularized the law of the minimum for agriculture, which states that growth is limited by the least available resource. It was soon discovered that this was often some form of phosphorus.

As a consequence, bones – comprised mostly of calcium and phosphate – from old battlefields were dug up to use in farming. Guano, large accumulations of bird droppings, also contains high concentrations of phosphorus and was used to fertilize crops. But supplies of this were soon depleted. As demand increased, supplies had to be mined instead.

But this applied inorganic phosphate fertilizer is highly mobile and leaches into watercourses. In addition, phosphate rock weathers and is also ultimately washed into the ocean where it either deposits as calcium phosphate or is taken up by marine organisms who also eventually deposit on the ocean floor when they die. Consequently, terrestrial phosphorus doesn’t really disappear, but it can move beyond our reach.

Natural Wastage

To complicate matters further, even the phosphorus we can use is largely wasted. Of the phosphorus mined as fertilizer, only a fifth reaches the food we eat. Some leaches away and some is bound to calcium and iron in the soil. Some plant roots have the ability to extract the latter, but not in large enough quantities to retrieve all of it.

In addition to these inorganic forms, phosphate is also converted into cellular compounds, creating organically-bound phosphorus, such as phospholipids or phytate. After the death of an organism, these organic phosphorus compounds need to be returned into the useable phosphate form. How much organically-bound phosphorus is present in soils depends on the number and activity of the organisms that can do this.

Phosphorous boosts crop yields. (Credit: Shutterstock)

Agricultural soils are usually rich in inorganic phosphorus while in undisturbed ecosystems, such as forests and long-term pastures, organically-bound phosphorus dominates. But agricultural land is often depleted of phosphorus during harvest and land management practices such as ploughing, hence the addition of phosphate-containing fertilizers.

Spreading manure and avoiding tillage are ways of increasing microbial abundance in the soil – and so keeping more phosphorus in an organically-bound form.

The risks of peak phosphorus can be countered with some simple solutions. Eating less meat is a start as huge amounts are used to rear livestock for meat. The chances are that agricultural yields are limited by phosphorus availability and will be further stretched as the global population grows.

Humans are themselves wasteful of phosphorus, as most of what we take in goes straight out again. Fortunately, technologies have been developed to mine phosphorus from sewage, but at present are too expensive to be practical.

Peak phosphorus does not mean that phosphorus will disappear, rather that the reserves with mineable high concentrations are depleting. Instead, we are increasing the background concentrations of phosphorus and adding it to the ocean floor. More sustainable phosphorus use requires a greater appreciation and understanding of the many organisms that make up soils – and the part they play in phosphorus distribution – or we may no longer be able to feed the world at an affordable price.

 

This article was originally published on The Conversation. Read the original article.

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

VX Nerve Agent: The Deadly Weapon Engineered in Secret

By Carl Engelking | February 24, 2017 4:30 pm
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A World War II-era contamination suit. (Credit: Shutterstock)

In January 1958, two medical officers at Porton Down, Britain’s military science facility, exposed their forearms to 50-microgram droplets of a substance called VX, which was a new, fast-acting nerve agent that could kill by seeping through the skin.

VX, short for “venomous agent X,” is tasteless, odorless and causes uncontrollable muscle contractions that eventually stop a person’s breathing within minutes. That experiment in 1958, according to University of Kent historian Ulf Schmidt, was perhaps the first human test of VX in the Western world. Read More

What Causes a ‘Butterflies in the Stomach’ Sensation?

By Bradley Elliott, University of Westminster | February 21, 2017 7:00 am
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(Credit: Shutterstock)

If you have ever been nervous about something that is about to happen, then you may have felt the sensations of nausea and “fluttering”—the recognizable and odd sensation deep in your gut known as having “butterflies in the stomach.”

Perhaps you were about to give a speech to a large audience, were in the waiting room for a big interview, were about to step up and take a key penalty shot or about to meet a potential love interest. Rather than actual butterflies bouncing around your large intestine, of course, there is of course something more scientific going on—and it’s all down to your nervous system. Read More

CATEGORIZED UNDER: Top Posts, Uncategorized

Collective False Memories: What’s Behind the ‘Mandela Effect’?

By Caitlin Aamodt | February 16, 2017 1:45 pm

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Would you trust a memory that felt as real as all your other memories, and if other people confirmed that they remembered it too? What if the memory turned out to be false? This scenario was named the ‘Mandela effect’ by the self-described ‘paranormal consultant’ Fiona Broome after she discovered that other people shared her (false) memory of the South African civil rights leader Nelson Mandela dying in prison in the 1980s.

Is a shared false memory really due to a so-called ‘glitch in the matrix’, or is there some other explanation for what’s happening? Broome attributes the disparity to the many-worlds or ‘multiverse’ interpretation of quantum mechanics. Read More

CATEGORIZED UNDER: Mind & Brain, Top Posts
MORE ABOUT: Memory & learning

Metagenomic Sleuthing Treats Illness Like a Crime Scene

By Kim Smuga-Otto | February 16, 2017 1:09 pm

Charles Chiu in the lab with colleague Steve Miller. (Credit: Elisabeth Fall/UCSF)

Pathogens move fast.

You wake up one morning feeling ready to take on the world. On your way to work, you notice your throat’s a bit scratchy, your forehead a bit warm. By lunch you’ve got a pounding headache and it hurts to breathe. Co-workers agree, you’ve got whatever’s been going around. You end the day early, using the last of your strength to drag yourself to bed. Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: genes and health

When Earth Became a ‘Mote of Dust’

By Shannon Stirone | February 14, 2017 12:28 pm
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Earth, seen as the faint dot in a sunbeam, is 4 billion miles away in this image from Voyager 1. (Credit: NASA/JPL)

We glimpsed Earth’s curvature in 1946, via a repurposed German V-2 rocket that flew 65 miles above the surface. Year-by-year, we climbed a little higher, engineering a means to comprehend the magnitude of our home.

In 1968, Apollo 8 lunar module pilot William Anders captured the iconic Earthrise photo. We contemplated the beauty of our home. Read More

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

Has Dogma Derailed the Search for Dark Matter?

By Pavel Kroupa, University of Bonn | February 6, 2017 12:56 pm
dark-matter

A Hubble composite image shows a ring of ‘dark matter’ in the galaxy cluster Cl 0024+17. Courtesy NASA, ESA, M.J. Jee and H. Ford. (Credit: Johns Hopkins University)

According to mainstream researchers, the vast majority of the matter in the Universe is invisible: it consists of dark-matter particles that do not interact with radiation and cannot be seen through any telescope. The case for dark matter is regarded as so overwhelming that its existence is often reported as fact. Lately, though, cracks of doubt have started to appear. In July, the LUX experiment in South Dakota came up empty in its search for dark particles – the latest failure in a planet-wide, decades-long effort to find them. Some cosmic surveys also suggest that dark particles cannot be there, which is especially confounding since astronomical observations were the original impetus for the dark-matter hypothesis. Read More

CATEGORIZED UNDER: Space & Physics, Top Posts
MORE ABOUT: dark matter
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