Age-Old Problem: River in Jordan Polluted by Copper 7,000 Years Ago
The first river polluted by humanity may have been discovered in Jordan, contaminated by copper about 7,000 years ago, a new study finds.
Scientists examined a now-dry riverbed in the Wadi Faynan region of southern Jordan. Archaeologist Russell Adams at the University of Waterloo in Canada and his colleagues have been studying the area for more than 25 years to learn more about a critical turning point in history — the origins of metallurgy, when humans began moving from making tools out of stones to making tools out of metal.
"The region is famous as one of the principal sites in the Middle East where copper occurs that can easily be mined," Adams told Live Scien
Copper production began in this region during the Chalcolithic, or Copper Age, which took place between about 5000 and 3200 B.C. in this region, Adams said. The Chalcolithic Age was a transitional period during the late Neolithic, or Stone Age, and the beginning of the Bronze Age.
"These populations were experimenting with fire, experimenting with pottery and experimenting with copper ores, and all three of these components are part of the early production of copper metals from ores," Adams said in a statement. "The technological innovation and the spread of the adoption and use of metals in society mark the beginning of the modern world."
This early copper production involved combining charcoal and the blue-green copper ore found in abundance in this area in pottery crucibles or vessels and heating the mixture over a fire. The process was time-consuming and labor-intensive, so it took thousands of years before copper became a central part of human societies, the researchers said.
Over time, communities in the region grew larger and copper production expanded. People built mines and then large smelting furnaces and factories by about 2600 B.C., the researchers said.
"This region is home to the world's first industrial revolution," Adams said in the statement. "This really was the center of innovative technology."
Among other things, Adams and his colleagues were interested in the long-term effects of copper production on the environment in this region. "There are places in the Wadi Faynan basin where the pollution from the copper smelting residues, the slag, are significant health risks, and probably would've been that way for a long time," Adams said.
The international research team's analysis of the sediments in the area suggested that pollution of a meandering stream that once ran in Wadi Faynan began about 7,000 years ago. "This is the earliest example known yet of humanity's pollution of the world," Adams said.
The slag from copper production contained metals such as copper, lead, zinc, cadmium, and even arsenic, mercury and thallium. Plants absorbed these metals, and then people and animals such as goats and sheep ate them.
Pollution from millennia of copper mining and production likely led to widespread health problems in the region, such as infertility, newborn malformations and premature death, Adams said. He said that prior work examining human bones from Roman cemeteries in the region "found unhealthy levels of metals in people, and these were not necessarily people involved in mining and smelting themselves — many were infants and juveniles. There was clearly uptake of environmental pollution into the food chain."
Future research could look for signs of contamination in various parts of this region to learn more about how pollution in this area might have varied over time, Adams said.
The scientists will detail their findings Dec. 15 in the journal Science of the Total Environment.
Original article on Live Science.
Flexible Film Captures Energy from Motion
At least once a week, Nelson Sepulveda gets on one of his bikes and rides 35 miles or more. He gets a good workout on those days, but as an associate professor of electrical and computer engineering at Michigan State University, he knows some of it is wasted energy. All of that pedaling could be harnessed and converted into electricity to power his phone or some other electronic gadget.
This week, Sepulveda and his colleagues report in the journal Nano Energy on a new film-like material capable of turning motion into electricity. The material is similar to other piezoelectrics in that it generates a voltage when it's squeezed or pressed. But what sets this one apart is that it's paper thin and flexible and each time it's folded, the voltage increases.
"This increased voltage upon folding is not possible using other solid piezoelectric materials," Sepulveda told Seeker.
If that voltage could be efficiently directed into a current, it could reduce the nuisance of recharging or even eliminate it.
'What if you could take the mechanical energy from swiping pages on your tablet and use that to charge the battery of the device itself?" said Sepulveda. "That could reduce the time required to recharge your device."
To create the device, Sepulveda and his team used a combination of fabrication techniques and thin layers of substances including silver, polyimide, polypropylene ferroelectret and electrically charged particles onto a silicon wafer, creating a sheet that was peeled away from the chip as if it were a sticker.
The researchers conducted a few tests using different sizes of the piezoelectic sheet to measure its voltage. In one test a palm-sized sheet cranked out about 50 volts was able to power 20 LED lights.
When they folded the film-like piezoelectric material, the voltage increased exponentially.
Although producing a high voltage is promising, said Sepulveda, it's not enough. The researchers need to tweak the material so that its energy potential can be converted into a current. Sepulveda compared the voltage to water contained in a huge tower at the top of a mountain. The water pressure would be enormous.
"But that's just the force," he said.
The water's flow — it's current — depends on the pipes. How big are they? How long are they? What route do they take? If there are no pipes or the pipes take a convoluted route, the pressure may be very small by the time the water reaches a home faucet.
It's the same for voltage. "I could have a million volts and no current," he said.
Sepulveda told Seeker that he and his team have engineered at least one solution to converting the high voltage generated by the device into a flow of charge, but they were still trying to nail down the science of why it worked. He said it was too early to discuss the details.
One day soon, though, he could have a wearable device that attaches to his knee and generates power while he bikes. That would turn his 35-mile ride into an energy-harvesting bonanza.
'That should probably give me enough energy to charge my cellphone," he said.
Why Don't Monkeys Talk Like Us
There is little doubt that non-human primates like Koko the gorilla are very intelligent. Koko, for example, uses sign language to communicate with people, telling them that she loves her pet cats, Miss Black and Miss Grey. Koko, however, is noticeably the strong and silent type, at least when it comes to speaking our language. She doesn't say a word.
They may not always show it, but new research, published in the journal Science Advances, suggests that non-human primates, even monkeys down on the food chain, have the vocal anatomy to produce clearly intelligible human speech. The discovery negates a long-standing theory that monkeys, gorillas, chimps and the like do not talk as we do because they are incapable of creating the sounds required for the skill.
"I hope that this new data dispels forever the widespread myth that monkeys and apes cannot speak because of anatomical limitations of their vocal tract," lead author Tecumseh Fitch of the University of Vienna's Department of Cognitive Biology told Seeker.
Fitch, senior author Asif Ghazanfar, Bart de Boer and Neil Mathur investigated the range of movements that primate vocal anatomy could produce. Using X-ray videos, they captured and then traced the movements of a macaque's tongue, lips, larynx and more as the monkey vocalized, ate and made facial expressions. The researchers then used these X-rays to build a computer model of a monkey vocal tract, allowing them to answer the question: What would monkey speech sound like, if a human brain were in control?
You can hear the results, first with the monkey model saying, "Will you marry me?" and then, "Joyeux Noel (Merry Christmas in French)."
(Recordings courtesy of Asif Ghazanfar, Princeton Neuroscience Institute; Image 1 Credit: Paul Asman and Jill Lenoble, Flickr; Image 2, showing Tecumseh Fitch in his lab: University of Vienna)
The experiment worked out great, and yet we're still left with the fact that monkeys and apes do not talk as we do. The explanation turns out to be more complex, and controversial, than you might think.
First, Fitch and his team believe that most mammals possess flexible, speech-ready vocal tracts. He said, "It seems clear that this type of flexibility evolved early on, for reasons other than vocalization, probably initially for food processing—manipulating and swallowing food."
He suspects that humans evolved at least two important changes to our brains that give us a communication edge.
Fitch explained, "We have direct connections between our motor cortical neurons and the neurons that actually control the vocal tract musculature, particularly those in charge of the larynx; and we have much more substantial connections, within our cortex, between the auditory cortex—responsible for hearing sounds—and the motor cortex, responsible for making sounds."
Fitch says there are many theories attempting to explain how humans evolved both the brain and the vocal tract for speech. One of his favorites was formulated by famed British naturalist Charles Darwin, who theorized that our ancestors initially evolved to become "singing apes," or kind of a cross between gibbons and songbirds and being able to learn new songs. This musical ability, Darwin suspected, emerged first, and then later was put to use in speech.
Fitch thinks it is unlikely we could teach non-human primates to speak, save for the remote chance that genetic engineering in future might make this possible.
Laurie Santos, a psychology professor at Yale University, told Seeker the paper "opens whole new doors for finding the key to the uniqueness of humans' unparalleled language ability."
On the other hand, Constance Scharff, a professor in the Department of Animal Behavior at Free University Berlin, indicates we may undervalue the communicative skills of animals, many of which—like parrots—are clearly very vocal.
Scharff told Seeker that she is glad the new study "puts another nail in the coffin of the idea that the absence of speech in macaques cannot be explained by an unsuitable vocal tract." Scharff also agrees that monkeys "do not seem to have the same regions and neural connections in their brains that humans use."
But, she quickly added, "there are other ways imaginable to achieve speech." She pointed out that parrots, seals and elephants either use quite different brain regions to vocalize, or the underlying systems remain largely unknown.
"As many experiments have recently shown," she added, "animals might not do things under natural conditions, but are capable of doing them when trained and prompted, such as sea lions and parrots moving to a beat."
"I am aware that so far the evidence in macaques points against 'speech-ready' neural hardware, but I think we do not know enough about all the ways brains can produce sounds in a speech-like way to say, 'Macaques don't because their brains can't.'"
Trump Chooses Climate Denier for Secretary of Interior
U.S. Rep. Cathy McMorris Rodgers, a sixth-term Republican from Washington State who is a climate change denier and an ardent opponent of regulations for greenhouse gas emissions, has been nominated by President-elect Donald Trump for Secretary of Interior.
If McMorris Rodgers is confirmed by the U.S. Senate, she would govern the management of more than 500 million acres of federal public lands, including more than 400 national parks.
Perhaps most critically, she would oversee the development of many of America's fossil fuels and renewables resources, including all of its offshore oil, gas and wind development. Federal land is the source of more than 20 percent of all the oil and gas and 40 percent of the coal produced in the U.S.
McMorris Rodgers would have the power to reverse Obama administration efforts to protect federally managed waters from oil and gas development as well as end the research into how coal mining affects the climate. Earlier this year, the Obama administration placed a three-year moratorium on federal coal leasing, and closed the entire East Coast and parts of the Arctic Ocean to offshore oil drilling.
The land the Interior Department manages stores atmospheric carbon in trees and tree roots; protects biological diversity in wilderness areas, forests and national parks; and provides water for millions of people, mainly in the West.
McMorris Rodgers would also have wide-ranging influence over how the National Park Service and the U.S. Geological Survey communicate to the public about global warming, potentially troubling in light of her denial of climate change and climate science.
"Scientific reports are inconclusive at best on human culpability of global warming," McMorris Rodgers falsely told the Spokane, Wash., Spokesman-Review newspaper in 2012. "Regardless of which theory proves correct, the goal is the same — to reduce carbon emissions, we need innovation in the private sector; not excessive government regulation to stifle some industries while rewarding others. I oppose 'cap and trade' and other big government schemes because they will destroy jobs while likely having minimal impact on the climate."
McMorris Rodgers signed a 2012 pledge sponsored by Americans for Prosperity, a conservative political advocacy group funded by billionaire David Koch, promising that she would oppose any federal climate-related legislation that would raise revenue for the federal government, including a carbon tax.
Coming from Washington State, which is highly dependent on large hydroelectric dams for its electricity, McMorris Rodgers is a vocal supporter of hydropower and nuclear energy and has sponsored legislation expanding the development of small hydroelectric dams nationwide — a valuable source of renewable energy.
But she is also a major proponent of drilling public lands for fossil fuels.
The League of Conservation Voters gives McMorris Rodgers a 4 percent lifetime score out of a possible 100 in their environmental scorecard because she has voted against bills that would have required the federal government to account for the social cost of carbon in administrative actions and required federally funded projects to be resilient to the impacts of climate change.
McMorris Rodgers has supported legislation that would have opened the Outer Continental Shelf to oil drilling, and opposed the U.S. Environmental Protection Agency's ability to regulate greenhouse gas emissions as an air pollutant. She has also voted against tax credits for renewable electricity.
"That is not a record that is likely to inspire confidence from the environmental community," said Mark Squillace, a natural resources law professor at the University of Colorado-Boulder. "On the other hand, I don’t sense that she has been a leading voice on public lands issues and so perhaps she will take a more conciliatory approach if she is confirmed as Interior Secretary."
He said that McMorris Rodgers has mostly voted with other Republicans on environmental and public lands issues.
"She also serves on the House Energy and Commerce Committee, but again I have not seen clear signs of leadership on energy issues, other than a pattern of consistent votes in favor of fossil fuels and against taking action on climate change," Squillace said.
In 2011, McMorris Rodgers co-sponsored a bill that would have required the Interior Secretary to sell off more than 3 million acres of public lands in 10 western states, a bill driven largely by western Republicans who believed the land served no specific purpose. Selling it would have raised more than $1 billion for the federal government, Utah Sen. Mike Lee said at the time.
As Interior secretary, McMorris Rodgers will oversee water management in much of the West. The department's Bureau of Reclamation operates 476 dams and 348 reservoirs across the country, and it is in charge of numerous scientific endeavors and mapping the entire globe through the U.S. Geological Survey.
Robert H. Nelson, a professor of public policy focusing on public lands management at the University of Maryland and a proponent of the federal government transferring federal public lands to the states, said that what's most notable about McMorris Rodgers' nomination is that, unlike other Trump cabinet nominees, she does not appear to be a well-known activist.
"If he had done that, he would have picked someone from a state like Utah," Nelson said, referring to Trump. "Her district, however, along with the rest of Washington State, is heavily affected by hydropower supplied from federal dams. There she has a higher profile. She has publicly supported, for example, keeping the four Snake River dams that many environmentalists would like to tear down."
Other experts and conservationists are grim about the future of public lands under McMorris Rodgers.
"Together the pro-fossil fuel team of McMorris at Interior and Scott Pruitt at EPA is a disaster in the making for efforts to reign in CO2 before we hit truly awful tipping points," said Jack Tuholske, director of the Vermont Law School Water and Justice Program. "Federal lands have enough coal, oil and gas to push us over any reasonable carbon threshold. President Obama has been fairly successful in limiting access to those resources, especially in his second term. All of those efforts could be undone with Trump's team in place."
Dominick DellaSala, chief scientist of the Geos Institute in Ashland, Ore., said McMorris Rodgers is no fan of the National Environmental Policy Act, the law that requires environmental review of new development and land management changes on federally owned land.
McMorris Rodgers is "bad but could be worse on these issues," DellaSala said. "She's not likely to champion public lands conservation issues."
Gary Wockner, director of Save the Colorado, a group advocating for conservation and preservation of the Colorado River, said McMorris Rodgers has an "extreme" anti-environment voting record.
"The U.S. Senate should do everything in its power to stop her appointment and stop Trump's impending war on the public lands, rivers, and wildlife of the West," Wockner said.
Smallpox Found in Lithuanian Mummy Could Rewrite Virus' History
The mummy of a child discovered in a crypt beneath a Lithuanian church harbors the oldest sample found to date of the virus that causes smallpox, a new report said.
But the researchers' analysis of the virus, called the variola virus, suggests that smallpox first appeared in humans much more recently than thought, the researchers said. Scientists had thought that smallpox was an ancient disease that plagued humanity for millennia.
The researchers drew their conclusion by taking virus from the mummy of the child, who lived between 1643 and 1665, and comparing that strain against variola viruses that date to the mid-1900s. The differences, or mutations, that the researchers found suggest that the strains shared a common ancestor that first arose between 1588 and 1645, the researchers said. That time period was filled with human exploration, migration and colonization — activities that could have spread the virus worldwide, the researchers noted.
More studies are needed to confirm that the smallpox virus indeed arose that recently, but if it did, this would cast doubt on the previously suggested idea that people in ancient Egypt had smallpox. Although 3,000- to 4,000-year-old Egyptian mummies have pockmark scarring, a symptom of smallpox, these scars could have also come from measles or chickenpox, said the study's first author, Ana Duggan, a postdoctoral fellow at the McMaster University Ancient DNA Centre in Canada.
If smallpox had arisen thousands of years ago, the researchers would have seen a high degree of diversity between the viruses that they compared, Duggan said. "We don't see that," she told Live Science.
In addition, the researchers' analysis of the mummy's virus also suggests that the two known forms of the virus — variola major and variola minor — likely split from each other after the English doctor Edward Jenner famously developed the first smallpox vaccine, in the late 1700s, the researchers said.
The finding about the major-minor split is "by no means conclusive, but it opens the idea that maybe this split between the major and the less virulent, minor strain was an evolutionary response to the vaccine," Duggan said.
Researchers have been studying several mummies found in the crypt of the Dominican Church of the Holy Spirit in Vilnius, Lithuania, since the 1930s. But the authors of the new study are the first to figure out that one mummy, of a child between ages 2 and 4, contained the smallpox virus.
It's unclear whether the child was male or female, but the researchers did establish, through radiocarbon dating, that the child lived about 360 years ago. Smallpox outbreaks were happening across Europe at that time.
Smallpox once killed about three out of every 10 people who got it. The illness could also lead to disfigurement and blindness. Smallpox is the first and so far only human disease eradicated by vaccination, Duggan said.
The researchers' sample of the variola virus taken from the mummy was badly disintegrated, but the scientists rebuilt it by comparing it to existing variola sequences, and also using DNA sequences from the mummy's skin, the scientists said.
Smallpox origins
The scientists said they are hopeful that the findings will help virologists trace the background of smallpox and other viruses. [27 Devastating Infectious Diseases]
"We still don't know when smallpox first appeared in humans, and we don't know what animal it came from. And we don't know that because we don't have any older historical samples to work with" study co-author Edward Holmes, a professor of evolutionary biology at the University of Sydney in Australia, said in the statement.
The new study puts "a new perspective on this very important disease, but it's also showing us that our historical knowledge of viruses is just the tip of the iceberg," Holmes said.
No comments:
Post a Comment