City of Beijing is sinking at rate of 11cm(4) inches per year.

The city of Beijing is sinking at a rate of up to 11 centimeters (4 inches) per year, according to a new study in the journal Remote Sensing. The cause of this perplexing plummet, say the researchers, is that the city’s groundwater has become depleted, causing soil to dry out and compress.

The study notes that Beijing is largely hydrated by underground reserves of permeable rock that transmit groundwater, known as aquifers. However, a surge in population, industry, and agriculture in the surrounding area has diminished these subterranean water reserves, causing the city to begin sinking in the 1930s.

Naturally, this is not helped by the fact that the Chinese megacity – which has a population of around 20 million – is laden with the weight of urban congestion and development. It is therefore unsurprising that Beijing’s financial district, where many of its skyscrapers are located, is among the most rapidly sinking neighborhoods.

Using satellite imagery and GPS data, the study authors were able to analyze topographical changes across the Chinese capital from 2003 to 2010, noting that the city is indeed descending. Though Beijing is far from the only sinking metropolis – Mexico City and Venice are two other examples – the fact that it is the fifth most water-stressed city on the planet suggests that the possibility of this trend continuing is high.

As the city’s residents continue to guzzle up around 3.5 billion liters (925 million gallons) of groundwater each year, the researchers are now concerned that the sinking streets could soon cause damage to buildings, railways, and other vital infrastructure.

Three of death.

Although it resides on chilled-out, tourist-friendly beaches, the manchineel tree (Hippomane mancinella) seems hell-bent on its vendetta against humanity.

This tree can found in the Caribbean, the Bahamas, the Gulf of Mexico, parts of northern South America, The Galápagos Islands and even in the U.S. state of Florida. When the Spanish first found the tree during their conquest of the Americas, they named it “arbol de la muerte,” which translates to "tree of death." Even touching its bark can leave you with chemical burns, although its notoriety and toxicity mainly lies in its fruit. Ingesting the sweet-smelling fruit can cause severe vomiting, diarrhea, and seizures.

Nicola Strickland, a consultant radiologist,wrote about her run-in with the “death apple”on her Caribbean holiday in Tobago. After mistaking the fruit for a crab apple, she and her friend took a small bite. Moments later, the “peppery” taste in their mouth turned into a burning sensation and within minutes they struggled to breathe as their airways closed up. Along with this, they developed severe pain in their necks as the toxin began to seep into their lymph nodes. Strickland and her friend were lucky to live; it is speculated they survived purely because they ate such a minuscule amount.

A manchineel tree's "death apple" on Santa Cruz Island, Galápagos. image credit: Jason Hollinger/Flickr. (CC BY 2.0)

The tree contains many toxins. However, it is believed most of the unsavory effects come from the organic compound phorbol. Scarily, pretty much every part of the tree contains these toxins, from its bark to its sap.

There are even stories of Caribbean tribes using the sap as an “au naturel” torture device. After tying their captives to the tree, they would then wait for the rain to wash the tree’s highly water-soluble sap over their body. The sap is so packed with toxins, contact with skin can cause blistering, burning and severe irritation.

“Burn it and send it to hell,” you might say. Unfortunately, setting fire to the wood will produce smoke, which will cause massive irritation to the eyes and is even known to cause temporary blindness.

Scientists accidentally discovered a new pigment.

Back in 2009, a lab full of chemists stumbled across a new pigment, more or less by sheer chance. After being heralded as “the creation of a near-perfect blue pigment,” this coincidental eureka moment is now being manufactured for artists’ brushes.

This burst of blue came about when scientists at Oregon State University (OSU) heated manganese oxide, along with other chemicals, to over 1,200°C (2,000°F). Although the scientists were actually looking at manganese oxide for some of its electronic properties, one of their reactions inadvertently birthed a new pigment: the catchily named “YInMn blue.”

The findings of the original study were published in the Journal of the American Chemical Society.

“Basically, this was an accidental discovery,” said Mas Subramanian, a Milton Harris professor of materials science in the OSU Department of Chemistry, in a statement. "Our work had nothing to do with looking for a pigment.

He added: “Then one day a graduate student who is working on the project was taking samples out of a very hot furnace while I was walking by, and it was blue, a very beautiful blue. I realized immediately that something amazing had happened.”

So, what’s so special about this blue? 

This pigment is far more stable when exposed to heat or acidic conditions. Additionally, unlike Prussian blue or Cobalt blue pigments, it doesn’t release cyanide and is not carcinogenic – that's always a plus. Not only that, the highly reflective properties of the new pigment means it could be used in paints that could help keep buildings cool by reflecting infrared light.

Subramanian told Artnet in a recent interview that the pigment has become a popular choice among artists because of its vivid color and resistant properties. The paint manufacturersShepherd Color Company have also licensed a patent and is now selling samples of YInMn blue.

He added: “Our pigment is useful for art restoration, because it is similar to ultramarine but really more durable.”