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
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.
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
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?
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.
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.
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.
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
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
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
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
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
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
For over two decades, 45-year-old, French documentary maker Jerome Delafosse has been diving into oceans the world over to film marine life, and he’s thrilled about his next expedition—above water. This spring, he will serve as chief explorer aboard the Energy Observer, a boat powered by the sun, wind and hydrogen. In a first-of-its-kind endeavor, Delafosse and his team plan to circumnavigate the globe over six years, visiting 101 ports in 50 countries, while relying entirely on renewable energy sources to reach their destinations.
Delafosse and his compatriot, 37-year-old Victorien Erussard, who is the boat’s captain, hope to renew the legend of this 30-meter-long, 13-meter-wide catamaran, which was built in 1982 and named Formule Tag. It won the Trophéé Jules Vernes for the team Enza New Zealand skippered by Sir Peter Blake. Currently, it’s being equipped with its new energy systems in the northwestern French port of Saint Malo. Read More