Quantcast
Channel: Popular Science | RSS
Viewing all 20161 articles
Browse latest View live

This Newfound Species Has The Highest-Pitched Call Recorded

$
0
0

A female Supersonus
University of Lincoln

Supersonus can hit the high notes. One species in this newly discovered genus of katydid hailing from the rainforests of Ecuador and Colombia can produce mating calls of a higher pitch than previously recorded for any arthropod, a vast group that includes insects and spiders. Usually katydids produce calls between 5 kHz to 30kHz--meaning that humans, who can hear up to 20 kHz, can enjoy the singing of some species. But the three new species in this group are unique, producing calls as high as 150 kHz, far beyond what you and I can hear (unless you are a human-bat hybrid). 

Speaking of bats, the authors of the study--published in PLOS ONE--said they think that the high-pitched calls allow the insects to communicate without being easily overheard by bats. Though some bats can hear frequencies this high, the "extreme ultrasonic" calls do not travel far and would be unlikely to be intercepted. 

The calls are made by the katydids' tiny wings, which produce sound as they are rubbed against one another. The wings reach such pitches by being quite small—less than 1 millimeter in length. For this reason, the katydids cannot fly. When slowed down enough for humans to hear, the calls sound like bouncing ping pong balls, study co-author Fernando Montealegre-Z, a biomechanics expert at the University of Lincoln in the United Kingdom, told National Geographic.









Commercial Drones To Fly Over Alaska

$
0
0

RQ-20 Puma
The Puma drone in military use.
Aerovironment

Drones are exciting pieces of technology, yet most of their applications are quite dull. One of the most common: flying over large, empty spaces to make sure everything is okay. Today, the Federal Aviation Administration announced the first-ever authorization of a commercial drone flight over land, and, as you might expect, it's not the sexiest of missions. The oil and gas company BP will fly a small drone over pipelines in Alaska. The first flight took place on June 8th.

BP is flying an Aerovironment Puma, which the U.S. Army and Marine Corps both used in Iraq and Afghanistan. It is hand-launched, has both an infrared and regular camera, and can be piloted remotely or fly autonomously on a pre-set path. Previously, both Puma and Scan Eagle drones were authorized to fly over Arctic waters, but authorization for overland flight is new.

Here's what the FAA says about how BP will use the drone:

The Puma AE is a small, hand-launched UAS that is about 4 1/2 feet long and has a wingspan of 9 feet. Using the information generated by the Puma’s sensors, BP hopes to target maintenance activities on specific roads and infrastructure, which will save time and support safety and operational reliability goals, while helping to protect the sensitive North Slope environment.

Below, the kind of landscape the drone will be flying over.

Prudhoe Bay Oil Fields, North Slope, 1971
These are some of BP's oilfields in Alaska.
U.S. Fish and Wildlife Service







In The Future, Your Car Interior Could Be Made Of Tomatoes

$
0
0

A lovely little tomato.
Photo by photon_de on Flickr, as licensed under Creative Commons.
Ford Motor Company said this morning that it plans to develop a recycled material using the waste of another U.S.-based giant: the H.J. Heinz company. If the project is successful, you may some day see the stems, skin, and otherwise unused tomato parts from ketchup production in your car. Ford is currently in the early stages of exploring how to turn the byproducts of ketchup into composite materials used to make wiring brackets, or a storage bin.

Ellen Lee, Ford's technical expert in plastics research, tells Popular Science that as a material source, tomatoes can be a bit problematic—they lack some properties that help in stiffness, and like other natural fibers, tomato fibers don't always compact as well to feed into equipment. But the team is working with other material suppliers who work with natural fibers to develop ideas on how to handle these hurdles. 

About 14 years ago, the research team at Ford began looking into this larger field of developing and integrating more recyled and plant-based materials in vehicles (using ingredients such as coconut, recycled cotton, rice hulls, and soy). Right now, Lee says that the team is at the early end of development, having validated some initial feasibility of the concept.








The 'Mother Of Forensic Science' Built Dollhouse Crime Scenes

$
0
0

At work
Frances Glessner Lee at work on the Nutshell Collection, 1940s-1950s
Glessner House Museum
Frances Glessner Lee grew up in a wealthy household at the end of the 19th century. Hers was a lonely and sheltered childhood. She married at age 20, and didn't get to pursue her dream of becoming a doctor or a nurse--as her father said, "A lady doesn't go to school." But she nursed an interest in medicine and forensics, and after a scandalous divorce in 1914 and a large inheritance from her parents, she began pursuing her passions.

Lee gave some of her inheritance to Harvard University to create a professorship in legal medicine. Later, she began building miniature recreations of crime scenes to teach students about the art/science of evidence gathering--since she couldn't very well take people to actual crime scenes.

As Rachel Nuwer describes in an engrossing and macabre post at Slate, Lee created 20 of these dollhouse miniatures, which use tiny dolls to represent real victims of crimes. They were used--and still are, to this day--for forensic training. For her contributions, she earned the nickname “the mother of forensic investigation,” at a time when few women were involved in the field.

Lee called these mini-worlds Nutshell Studies of Unexplained Death. “She came up with this idea, and then co-opted the feminine tradition of miniature-making to advance in this male-dominated field,” Corinne May Botz, an artist and author of The Nutshell Studies of Unexplained Death, told Slate.

As Nuwer writes:

The 20 models Lee created were based on actual crime scenes, and she chose only the most puzzling cases in order to test aspiring detectives’ powers of observation and logic. Moreover, many of the cases could not be solved by observing the crime scene alone, demonstrating the need to involve medical examiners and other scientific experts in the process of solving crimes. While some… were most definitely the victims of foul play, others could have died of natural causes or suicide. It was up to the detectives to find out.

The Nutshells are now housed on the fourth floor of Maryland's Office of the Chief Medical Examiner, in behind a door marked “Pathology Exhibit.” Although not open to the public, they still get many visitors, ranging from "detectives to artists to miniatures aficionados."

Check out the whole post at Slate, which has photos of the Nutshells.








Google Buys A Maker Of Small Imaging Satellites

$
0
0

photo of the SkySat-1 satellite in a clean room
Skybox Imaging's SkySat-1 in a Clean Room
Skybox Imaging, Inc.

Google is now expanding across more of space. The search-engine company is buying Skybox Imaging, a Silicon Valley-based startup that makes small, cheap satellites that take photos at high resolution.

Google plans to use photos from the one Skybox satellite now in orbit for Google Maps, the Associated Press reports. Further in the future, perhaps Skybox's little sats will relay something else. As we've reported, Google hopes to spread internet access around the world using three flying technologies, balloons, high-altitude solar-powered drones and satellites.

Skybox craft could be a part of that ambitious project, the AP suggests. However, Google is already working on a project with leaders from another satellite company, O3b Networks, which specializes in lower-orbit satellites for beaming internet signals to Earth, so maybe it will use Skybox satellites for something else.

[AP]








Removing Salt To Relieve The World’s Thirst

$
0
0

Photograph by Jonathon Kambouris

The Challenge

Seventy percent of the Earth’s surface is liquid—yet water scarcity affects more than a billion people each year. Since the 1970s, the gold standard for desalination has been reverse osmosis, in which big pumps push seawater through membranes that allow water molecules to pass through but not salt. The process is effective—it removes 99 percent of the salt—but it’s costly and energy-intensive. Put another way, today’s desalination technology exacerbates climate change and worsens the water crisis it’s meant to solve.

The Big Idea

By leveraging electricity rather than force, Kyle Knust, a 26-year-old doctoral student in analytical chemistry at the University of Texas at Austin, created an energy-efficient way to separate salt from saltwater with an electric current. His device is called the Waterchip (it’s small enough to fit in the palm of a hand), and water flows through it along a Y-shaped microchannel. An electrode emits a charge where the Y splits, creating an electric field that deflects the salt down one branch of the channel as highly concentrated brine. Desalinated water runs out the other arm. Tony Frudakis, CEO of Okeanos, a Cincinnati-area start-up, licensed the device. A single Waterchip removes about 25 percent of the salt from seawater and produces a mere trickle. “The technology is infinitely scalable,” he says. Running a few Waterchips in a series could make the output progressively purer, and running millions in parallel could theoretically produce as much freshwater as any giant reverse-osmosis plant—and consume half the energy. 

This article originally appeared in the June 2014 issue of Popular Science.

Read the rest of Popular Science’s Water Issue.








Last Straw: How The Fortunes Of Las Vegas Will Rise Or Fall With Lake Mead

$
0
0

Lake Mead
White mineral deposits circling Lake Mead behind Hoover Dam have emerged as water levels have fallen.
Jim Wilson/The New York Times/Redux

The bathtub ring can be seen for miles. The 120-foot-high band of rock, bleached nearly white by mineral-rich water, circles the shoreline of Lake Mead. Water levels have dropped by almost 100 feet in the past decade, and the ring has emerged as a stark reminder of the drought enveloping the American Southwest. It also represents a looming crisis for the largest drinking-water reservoir in the U.S., one that has prompted the most ambitious water-construction project in recent history.

Right now, 600 feet beneath the lake’s glassy blue surface, a massive custom-built tunnel-boring machine—almost as long as two football fields and heavier than four 747s—is plowing inch by tedious inch through wet, fractured bedrock. Spanning nearly 24 feet in diameter, its rock-gnawing face is alive with the movement of 44 disc cutters and 23 knives. The Big Gulp–style tunnel it is boring will eventually intersect with a concrete-and-steel riser installed in the bottom of the lake, like a drain. Two intake pipes already carry water from Lake Mead to Las Vegas, about 25 miles to the west. Known as the Third Straw, Intake No. 3 will reach 200 feet deeper into the lake—and keep water flowing for as long as there’s water to pump.

Lake Mead is more than half empty. If the water drops another 50 feet, the first intake pipe will start sucking air.

“It basically drought-proofs our existing intakes,” says Erika Moonin, the project’s manager and a 17-year veteran of the Southern Nevada Water Authority. “There’s a high chance we could lose Intake No. 1 if the drought continues to worsen, and the projections right now don’t look too good for the next two years.” I meet Moonin, who’s paired a silky turquoise blouse with her steel-toed boots and hard hat, at a construction site several hundred yards from the reservoir. She talks me through a map that shows how the new three-mile-long intake tunnel will link to an existing pumping station through a connector tunnel half a mile long. “Barring no real drastic changes,” she says, “we think we can finish before Intake 1 goes dry.”

The current 14-year drought is the most severe since recordkeeping for the Colorado River began, in 1906, and Lake Mead is now more than half empty. On the day of my visit in early February, the water’s surface elevation was 1,108 feet above sea level (the Third Straw will meet the lake bed at 860 feet). If the water drops another 50 feet, the first intake pipe will start sucking air. That’s a problem for Las Vegas, which gets 90 percent of its water from the pipes. But it’s also alarming for everyone to the south. The Hoover Dam, just around the corner from the construction site, releases water downstream to a series of smaller reservoirs and canals that deliver water to communities throughout the Southwest, including my Los Angeles neighborhood.

Lower Colorado River Diversions
Between 2004 and 2013, the average flow of water from the Glen Canyon Dam, just upstream from the Lower Colorado River Basin, was 8.88 million acre- feet. From there, water was diverted to cities and farms in Nevada, Arizona, and Southern California. By the time it reached Mexico, the flow was 1.55 million acre feet. This year, for the first time in decades, 1 percent of the annual flow was released to nourish the river’s long-dried delta.
Flow data for lower Colorado River for 2004-2013 courtesy Bureau of Reclamation


Between 2004 and 2013, the average flow of water from the Glen Canyon Dam, just upstream from the Lower Colorado River Basin, was 8.88 million acre- feet. From there, water was diverted to cities and farms in Nevada, Arizona, and Southern California. By the time it reached Mexico, the flow was 1.55 million acre feet. This year, for the first time in decades, 1 percent of the annual flow was released to nourish the river’s long-dried delta.

I pull on rubber boots, a hard hat, safety glasses, and an orange vest and follow Moonin past a wide berm of excavated rock and thousands of neatly stacked concrete slabs. We head up a dirt road toward the shaft that leads to the connector tunnel, and when we reach it I climb into the “birdcage.” The canary-yellow metal box clangs shut, and then a crane slowly begins to lower it 450 feet down the shaft. Inside, it’s immediately warmer and wetter. Water trickles down the walls. “We spend a lot of time fighting water because we’re below lake level,” Moonin says.

The birdcage touches down near a half dozen construction workers setting rebar, and I walk past them to peer into the connector tunnel. It slopes up slightly and curves to the right before tapering off into blackness. A hundred feet to the north, it links to the shore end of the Third Straw, and a mile and a half past that, the tunnel-boring machine continues its grinding march. The machine has now eaten more than halfway from the shoreline to its destination: the “soft eye” in the side of the riser set into the lake bed. In less than two years, if all goes well, water will fill the void where I’m standing and rush toward a pumping station at three feet per second.

I can’t help but admire the scale of the project. But it’s impossible to forget that this is also an act of desperation, a last-gasp attempt to keep water flowing from a river that at many spots has already become more a trickle than a torrent. Las Vegas and cities throughout the West continue to grow, and that’s prompted a race to build infrastructure faster than demand can make it obsolete.

From its headwaters in the Rockies, the Colorado River meanders 1,400 miles through five states and into Mexico, nourishing 40 million people and irrigating 5.5 million acres of farmland along the way. Despite decades of subsequent development, the water rights first established by the Colorado River Compact in 1922 remain essentially unchanged today. The agreement allocates 15 million acre-feet each year (picture an acre of land covered with a foot-high layer of water) among the seven Colorado River Basin states: Wyoming, Utah, Colorado, New Mexico, Nevada, Arizona, and California. The compact also acknowledged Mexico’s right to water, and in 1944, the nation was guaranteed 1.5 million acre-feet, bringing the total to 16.5 million. For many years, states rarely took all they were owed; currently, the river can’t come close to meeting demand.

Climate will exacerbate the problem. Rainfall in the Colorado Basin could decrease 15 percent in the next 50 years.

We now know that these water rights were based on a grave misjudgment. “The Colorado River is grossly overallocated,” says Peter Gleick, a water expert with the Pacific Institute in Oakland, California. “We’ve given away more water than nature provides.” The 16.5-million figure was based on just two decades of Colorado River flow. Over the century spanning from 1906 to 2005, the average freshwater in-put to the system was actually only 15 million acre-feet. So rather than fluctuating as reservoirs should, Gleick says, “we’ve been in a situation where they’re going down and down and down.” The federal Bureau of Reclamation has predicted that the water level at Lake Mead could fall below 1,075 feet of elevation as soon as January 2016, prompting automatic reductions in the states’ allocations.

Even more troubling, scientists have learned by studying tree rings that the 20th century was one of the two wettest 100-year periods in the past 1,200 years. There have been many extended droughts in the Southwest over the past two millennia, some lasting for three decades or more. The water shortages occuring today might not be an aberration but a return to a historical norm.

Climate change will only exacerbate the problem. Models predict that rainfall in the Colorado Basin could decrease by 15 percent in the next 50 years. “Even 10 percent is brutal,” says marine physicist Tim Barnett, of Scripps Institution of Oceanography. If climate change continues to dry out the region, Barnett found in a 2009 study, Colorado River water deliveries could fall short 60 to 90 percent of the time by midcentury. Warmer temperatures will also increase evaporation from surface water and reduce the natural reservoirs of mountain snowpack that provide a steady source of meltwater, especially in summer. Scientists can’t say how much climate change is influencing the current drought, and in a way, it doesn’t matter. They do know climate change is happening and that it will make droughts worse.

Many places are slow to prepare for such a future. This drought has been particularly severe in California, where agriculture accounts for 80 percent of all water use. Forty percent of the state’s farmland is regularly submerged by flood irrigation, and farmers grow crops (such as rice) more appropriate to a wetland environment. Many residents’ water bills will remain disconnected from their actual usage, eliminating any financial incentive to conserve, until a new state law goes into effect in 2025. In much of the West, people haven’t worried a whole lot about water since the last extended drought, in the mid-1980s. The same is not true in Las Vegas.

The tunnel-boring machine for the 20-foot-diameter, three-mile-long Intake No. 3 can operate at up to 17 bars of pressure. A half-mile-long connector tunnel will link the intake to existing infrastructure near Lake Mead. Because both tunnels pass through wet, fractured rock, flooding has been a constant challenge.
From left: AP Photo/Las vegas Review-Journal, Jeff Scheid; Jim Wilson/The New York Times/Redux; AP Photo/Las vegas Review-Journal, John Locher

In just about every way, Las Vegas is more extreme than the typical American city. Take population. In 1989, the Las Vegas Valley was home to 700,000 residents. Today there are more than two million. While Los Angeles sees an average 15 inches of rain a year, Phoenix, 8, and Albuquerque, 9.5, Las Vegas receives just 4 inches annually. The average daily high in summer is 103˚F. The region has virtually no agriculture and little industry. Instead, it has tourism: 40 million people a year who, when they land in the Mojave Desert, seek only an oasis—the dancing fountains of the Bellagio, the imitation Venetian canals, pirate ships, swimming pools, and golf courses.

Vegas’s appeal is excess, and that extends to water. In fact, it’s hard to find a spot on the Strip where you can’t hear water as well as see it. The fountain in front of the new 4,000-room Aria hotel is more modest than most: delicate sprays of water incorporating beams of color. I enter the soaring lobby to find Chris Magee. Water brought Magee to Vegas too—first on a college swimming scholarship, then as a lifeguard at a resort pool. Now he’s the executive director of sustainable facilities for MGM Resorts International, which owns the Aria as well as Mandalay Bay and other iconic Vegas properties.

“The way we look at it, there are two types of water: consumptive and nonconsumptive,” he says. Water used for landscaping is mostly consumptive; it evaporates or seeps into the ground. “The nonconsumptive is everything that we capture back. Almost every drop of water that goes into a drain gets back into Lake Mead.” We weave through the casino and take an elevator up a few dozen floors to a luxury suite, where Magee points out low-flow fixtures and appliances. Here, and in every hotel room and home in the city, the wastewater from each shower, laundry load, and, yes, toilet flush is piped to a treatment plant, cleaned, and then spit out down a natural wash and back into Lake Mead. Once it rejoins reservoir water, it can flow back into the intake pipes to be treated and sent out city taps again. Almost half the water Las Vegas consumes now returns to the lake.

The rock beneath the lake is porous.Groundwater seeps in from the sides, and lake water threatens to flood the chamber from above.

Magee escorts me out, past spiky cacti and Seuss-like succulents. “Ten years ago, I don’t think anyone would have ever thought you’d find desert landscaping around a large hotel- casino development,” he says. Because homeowners use almost 70 percent of their water outside, their property, too, has been targeted for mandatory desert makeovers. Robert Kern is one of the water cops (officially, investigators) employed to patrol neighborhoods looking for cheats. When I meet Kern to accompany him on rounds, it’s hard to imagine him getting into even a mild confrontation. His soft, open face and quick smile make him seem more like a friendly mailman.

“This time of year, residents are only allowed to water one day a week,” he says, steering his pickup into a neighborhood of older single-family homes. Kern often follows tips from neighbors. People are self-conscious about water use, he says, and they know the regulations. “It’s everywhere: on their bill, online, on TV. The neighborhoods are policing themselves.” When this development was built, every home had a front and back lawn, Kern says. Not anymore. “Grass takes 55 gallons of water per square foot a year. A water-efficient yard might use 8 to 10 gallons.”

Drawing Straws
Las Vegas’s first two water tunnels cut through a spit of land called Saddle Island. The third extends three miles toward a deeper point in Lake Mead.
Lake Mead water data courtesy Bureau Of Reclamation. Locations of intakes courtesy Southern Nevada Water Authority

Las Vegas began ticketing errant water users in 2002, the driest year in recorded history on the Colorado River. The city now pays residents $1.50 a square foot to replace turf with desert landscaping. New developments can have grass on only half of a backyard’s square footage—and none in front. New commercial properties are banned from using ornamental grass. The median down the Las Vegas Strip, in fact, is made of synthetic turf.

As Kern drives, he keeps his eyes on the gutters. When he sees water, he follows it to its source. We track one rivulet to a single-story home made of pink stucco. There’s a date palm in the front yard, but the rest is all flat, green grass. This is the wrong day for watering, but the sprinklers are going full force, with misdirected nozzles spraying directly onto the sidewalk. Kern jumps out of the truck with a clipboard and video camera and documents the scene. A homeowner gets two warnings, he says. The first fine is $80. Then it doubles, up to $1,280 for a fifth violation. The fee appears as a line item on the water bill. “They can contest,” he says, “but in every case, there’s a video.”

Since 2002, Las Vegas has cut its water use by a third, from 314 gallons per capita a day to 212. There’s plenty more that could be done. Water remains remarkably cheap, for example: $1.16 per thousand gallons of water for the first tier of usage. I pay about three times that much for the same Colorado River water in Los Angeles. Las Vegas is in the middle of the desert, in the middle of a drought, in the midst of a population boom driven by retirees who want to replicate their East Coast gardens in the Mojave. Still, when greater shortages come, the city may fare relatively well. The Third Straw is a key component of that insurance policy.

Scooping out the Third Straw is like digging a subway tunnel, but with a significant added challenge: “It’s the highest-pressure tunnel excavated in the world to date,” Moonin says. The bedrock beneath the lake is porous; groundwater seeps in from the sides, and lake water threatens to flood the chamber from above. Inside the connector tunnel, sandbags separate a foot-and-a-half-deep river of water from the active construction zone; each minute, pumps push 1,450 gallons to the surface. The water problems in the main intake tunnel are far worse: When excavation first started, the workers had to wear full rain gear.

Since it broke ground six years ago, the $817-million project has been beleaguered by delays and cost overruns. In 2010, workers hit a fault zone, which caused flooding and forced engineers to reposition the tunnel at great expense. In 2012, a 44-year-old construction worker was killed and another injured by a high-pressure stream of mortar, which was released when a section of concrete came loose from the tunnel wall. For the past two years the tunnel-boring machine has alternated between atmospheric mode and pressurized mode, which requires the cutter head to pressurize a pocket of air at the rock face to keep water from forcing its way through. So far it’s encountered 14.5 bars of hydrostatic pressure.

Progress has been slow. Since tunneling for Intake No. 3 began in 2012, the borer has averaged just 35 feet per day in atmospheric mode. Pressurized mode advances as few as five feet a day. If construction finishes in July 2015, as it is now hoped, the project will be three years behind schedule. Of course, further delays are possible, if not likely. It still has more than a mile to go.

The Southern Nevada Water Authority, meanwhile, is working on an even more audacious Plan B: a 250-mile, $3 billion overland pipeline that would carry water from aquifers in the state’s rural eastern valleys to Las Vegas. First proposed 30 years ago, it remains mired in lawsuits. Construction is still at least a decade out.

The Driest Spell
Lake Mead’s water level has fluctuated since the reservoir first formed, but the current 14-year drought is unprecedented. At 1,075 feet, shortage conditions take effect, reducing allocations to southwestern states.
Lake Mead water data courtesy Bureau of Reclamation

Not long ago, it might have seemed like Las Vegas’s mammoth public works projects were an anomaly: extreme measures for an extreme city. Now they’re harbingers of things to come. In Carlsbad, California, construction is underway on a billion-dollar desalination plant and 10-mile pipeline that are projected to supply 7 percent of San Diego’s water by 2020. Further north, citizens have engaged in a heated debate over an estimated $15 billion project to dig two tunnels under the Sacramento–San Joaquin Delta—a plan that would improve delivery of river water, fed by Sierra Nevada snowpack, to farmers and cities to the south.

The Sierra Nevada had a record low snow year, but the same week I was in Las Vegas, Facebook friends posted triumphant selfies of themselves floating through two feet of fresh powder at Colorado ski resorts. By April, it was clear big parts of the Colorado River watershed had caught a break; Colorado Basin snowpack was up to 115 percent of normal. How much of that meltwater will end up in Lake Mead depends on a complicated calculation of when and how fast it melts.

What’s certain: It won’t be enough. As Gleick from the Pacific Institute observes, “The water infrastructure we built in the 20th century isn’t necessarily going to serve us in the 21st century. We’re going to have to do things differently.” And it’s going to cost us. As cities grow and the climate changes, water will become more valuable, and we’ll have to spend more money to manage it properly. Ultimately, the price we pay for water should increase as well. Because no number of straws can deliver enough water once there’s no water left to move.

In 2012, crews constructed a hollow riser on a barge in lake Mead and installed the structure 300 feet below the surface.
Courtesy of The Southern Nevada Water Authority

This article originally appeared in the June 2014 issue of Popular Science.

Read the rest of Popular Science’s Water Issue.








Building Soluble Circuits To Help End E-Waste

$
0
0

Photograph by Jonathon Kambouris

The Challenge

For every human on the planet—and there’s more than seven billion of us—43 pounds of electronic waste is generated each year. The United Nations predicts that by 2017, the figure will climb by as much as 30 percent. A lot of the refuse ends up in China, where locals burn it to extract precious metals. In the process, they inhale some of the most toxic chemicals in existence. According to researchers at Oregon State University, villagers living close to these e-waste dumps are 1.6 times more likely to develop cancer than urban dwellers who live in cities so polluted that particulates routinely block out the sun.

The Big Idea

John Rogers, a materials scientist at the University of Illinois at Urbana-Champaign, has created ribbons of silicon so thin—just 35 nanometers thick—that they can dissolve in 10 days in less than a millimeter of water. By combining these strips with magnesium and silk, he’s created circuits that safely degrade inside the human body. Such circuits could lead to a new era of smart biomedical devices, but, Rogers says, they’re also a first step in reducing e-waste. He’s now engineering dissolvable integrated circuits and antennas. By next year he aims to create soluble radio-frequency identification tags. Mark Allen, a micro-electromechanical engineer at the University of Pennsylvania, says, “Imagine a world of biodegradable devices that will allow people to throw away flexible tablets like newspapers.” 

This article originally appeared in the June 2014 issue of Popular Science.

Read the rest of Popular Science’s Water Issue.









Illinois Is First State To Ban Microbeads

$
0
0

Beads galore
Microplastic beads found recently in the Great Lakes.
5 Gyres / YouTube

Illinois has become the first state to ban microbeads, the small plastic bits often found in soaps and many different types of cosmetic products. The law, signed this week by Governor Pat Quinn, bans the manufacturing use of these synthetic beads by the end of 2018, and the sale of such items by the end of 2019 in the state. 

“I’m proud that Illinois is... taking the first step away from plastic microbeads toward natural exfoliants, and I’m optimistic that we’ve started a nationwide movement to protect not just the Great Lakes, but other bodies of water with high concentrations of microbeads,” said State Senator Heather Steans in a statement

It's well established that these synthetic microbeads accumulate in waterways including lakes and oceans, as they are small enough to make their way through water treatment facilities. Recent work has found 1.1 million plastic particles per square kilometer in Lake Ontario, for example. And they can be taken up by all a manner of animals, which can be harmful to their health. These plastic bits soak up a variety of pollutants, and there is a concern that when fish and other animals eat these plastic bits, they may transfer these chemicals up the food chain to humans and wildlife. (Microplastics can soak up and transport phenanthrene, for example, an ocean pollutant.)

Why use plastic beads anyway? The answer, in part: They are cheap, and people buy into them. There are many natural exfoliants that can be used, though, like sand, pumice, walnut shells, bits of kelp... or you could just use a wash cloth. 

[NPR]








Soot, Comet Ice, And Medical Powders All Have This Number In Common

$
0
0

photo of a student filling a graduated cylinder with plastic spheres
Why the Lab Goggles?
High school student Jessica Young fills a graduated cylinder with aggregates made from glued-together plastic spheres.
Baum/NIST

If you were to pack a bowl with billiard balls—I know, nobody does this in real life—you would find the balls filled the bowl to a density of 74 percent. If you were to pack a pool with bowling balls—really nobody does this in real life—the balls would fill the pool to a density of… 74 percent.

This is because 74 percent is the maximum density to which perfect spheres fill a space. It doesn't matter what size the spheres are. And abstract as this idea is, there is one "real life" application where the number shows up. In their mathematical models for predicting climate change, environmental scientists usually assume soot aggregates in the atmosphere in a densities of 74 percent. Soot is a major contributor to global warming, so it plays an important role in climate models.

In a new series of measurements, however, a team of researchers has discovered soot packs at a density of 36 percent, not 74 percent. Not only that, but a wide variety of real life things, including materials in comets, also pack to a density of 36 percent. Thirty-six percent might be a universal density for stuff that's made of small, rigid particles… which is includes more things than you might think.

Thirty-six percent might be a universal density.

To test their figure, the researchers made soot in their lab at the U.S. National Institute of Standards and Technology. They also recruited one college student and one high school student to perform a series of simple tests. The students glued plastic spheres together in aggregations that mimic the aggregations soot particles form in the air. Instead of filling a space evenly, the way billiard balls do, things like bits of soot tend to clump together in lacy-looking, fractal patterns. Then, different forces—ranging from the forces between molecules to the effects of gravity—pack the lacy stuff into rough spheres. So yes, two students spent their summer internship at NIST sticking plastic balls together in these funny lumpy spheres, then filling bowls and graduated cylinders with the spheres, then measuring the density at which the spheres packed. Science thanks you, students of the world.

Like the lab-made soot, the student-made plastic-ball aggregations packed at a density of 36 percent, the researchers found. When the scientists checked published scientific literature, they found numbers similar to 36 percent in several areas. Silicon dioxide used in ceramics fills at roughly that density, as do pharmaceutical powders whose grains tend to clump together. NASA's measurements for 20 comets estimate that they have a density ranging from 20 percent to 40 percent.

The NIST researchers published their work this week in the Proceedings of the National Academies of Sciences. They listed their students among the study authors.








Rugby Player Study Suggests Exercise Diversifies Gut Bacteria

$
0
0

Gut bacteria
E. coli, one of the many bacteria present in the human gut.
Rocky Mountain Laboratories, NIAID, NIH

It's World Cup season, so as our planet's eyeballs turn to soccer pitches, consider that flourishing communities of microbes in the players' guts. If you will. A new study found that elite athletes--in this case, professional Irish Rugby players--have extremely diverse gut microbiomes, compared with people of the same size who don't exercise. "This is the first report that exercise increases gut microbial diversity in humans," the authors wrote. 

In the study, published in the succinctly-named journal Gut, scientists took blood and fecal samples from 40 rugby players and from roughly the same number of non-athletes with a similar BMI (body mass index). They found that the athletes had significantly higher proportions of 40 taxa (or taxonomic groups of microbes) than their low-BMI, less active peers. The athletes also had a higher proportion of Akkermansiaceae, a bacterium linked with lower rates of obesity and metabolic disease. 

Generally speaking, a more diverse gut microbiota is quite good for overall health, and linked to higher resistance to illness and lower risk of obesity. A low diversity of gut microbes has been linked to obesity and to a diet that is high in fat and sugar compared with one that is low in fat and plant-based. 

The researchers don't know exactly how extreme exercise and a high protein diet yield such diversity, but they hope to find out, and use the results to enable them to treat G.I. problems associated with lower diversity. Clostridium difficile, which causes terrible diarrhea, is one such disease








How It Works: An Ultra-Precise Thermometer Made From Light

$
0
0

The light thermometer
A computer generated image of the Light Thermometer. A slight difference in the speed of the green and red light can tell us the temperature.
Credit: Dr James Anstie, IPAS and School of Chemistry and Physics, University of Adelaide

The world’s most sensitive room-temperature thermometer uses two colors of light to measure temperature with a precision of 30 billionths of a degree. This kind of precision far exceeds that of regular medical or home thermometers that we come into contact with. 

It all started when University of Adelaide professor Andre Luiten and Ph.D. candidate Wenle Weng encountered a problem while trying to stabilize fluctuating laser frequencies—small changes in temperature of a device in their experiment was disrupting results—so they sought to detect the temperature change and suppress it, as detailed in their paper. The device was a resonator, used to generate waves of a specific frequency, and crucial to the experiment. Luiten suggested the idea of sending two colors of lasers into the resonator and measuring the differences in frequency, and calculating the change in temperature. Light of different colors travels at different speeds in the same material, and that difference depends on the temperature of the material.

Here's how it works:

  1. Choose a dual-frequency laser that produces different colored light—in this case, it's infrared light and a green light. The colors chosen by the team depended on the availability of specific lasers in the lab. According to Weng, however, optimal color choices can improve the thermometer sensitivity even more.
  2. Beam the laser at your resonator, which is a crystalline disk. The crystalline materials (calcium fluoride and magnesium fluoride) were chosen for their transparent nature, which means light suffers the least loss when traveling inside these materials. The less light loss, the more accurate the measurements.
  3. The green and red light travels around the disk thousands of times—similar to the phenomenon known as a "whispering gallery," where sound waves cling to circular walls and allow whispered communication to be heard anywhere along the internal circumference. In this case, light waves are circulating the edge of the disk in the same way. 
  4. Measure the difference in the frequencies (equivalent to the travel speed) of the two colors and use the known relationship between temperature fluctuation and light frequency to calculate the temperature. Luiten notes that the experiment reveals "the minute fluctuations that occur in even a perfectly temperature-stabilized environment."

 

The unconventional light thermometer is currently the most sensitive thermometer that exists, if you're working at room temperature—three times more precise than the previous best. The team did note that it's possible to make thermometers more sensitive if you're using them at very cold temperatures. High-precision measurement of temperature change in biological interactions or chemical reactions at extremely small scales can help identify exactly what's happening in the reaction. The thermometer may also find applications in medical studies and materials engineering. 








Human In Robotic Exoskeleton To Kick Off The World Cup

$
0
0

The Exoskeletal Legs
Miguel Nicolelis

Sponsored URL

The most significant moment of the 2014 World Cup may take place not in the tournament's final match, but in its earliest minutes. If all goes according to plan, at the opening ceremony in Sao Paolo tomorrow, a paralyzed person will rise from a wheelchair, take several steps, and kick a soccer ball into a goal. The feat will be accomplished thanks to the Walk Again Project, a battery-powered, mind-controlled exoskeleton developed by an international team of scientists. According to the lead scientist on the project, Duke University neuroscientist Miguel Nicolelis, Ph.D., the kick will be a signal to the world that wheelchairs will soon become obsolete.

Since last year, Nicolelis has had his eye on the 2014 World Cup as the perfect opportunity to capture a victory for science. "I thought it was a way to show the World Cup can be more than just football and parties," he says. He hopes the most popular topic of conversation in Brazil, besides football, will be neuroscience.

The exoskeleton -- a system comprising a helmet implanted with a microchip that sticks out from the underside; a T-shirt loaded with sensors; metal leg braces; and a battery worn in a backpack -- is set in motion when the user envisions himself making the kick. The chip translates those electronic commands to a digital language that powers the skeleton, which then moves accordingly. The T-shirt vibrates to enhance the user's sensation of movement (and eliminate the need to look at his feet to see if he's stepping forward).

"It won't be herky-jerky," says Alan Rudolph, Ph.D., the vice president of research at Colorado State University and the managing director of the project. "The integration of the hardware and human signals will be significant, with truly elegant fine motor control."

The major advance over previous exoskeletal prostheses is how seamlessly the patient's thoughts control the movements of the suit. Nicolelis says that "interaction between the brain and the exoskeleton becomes so vivid, so clear that [patients] feel like they are walking by themselves. The body is doing the job, not the exoskeleton."

Nicolelis' grandfather suffered Parkinson's disease and his grandmother had a series of strokes, and "seeing the devastating effects" of these ailments motivated him to improve the lives of paralysis victims. In the 1990s, Nicolelis helped build the first mind-controlled arm. Using similar brain-machine interfaces in 2008, Nicolelis and his team tested the mind-control capabilities of an exoskeleton on a rhesus monkey. At first, while wearing the suit, the monkey ran on a treadmill and watched on a monitor as a robot in Japan mirrored its movement. Eventually the monkey was able to stand still and make the robot jog by only using its thoughts.

With the brain-machine interface working, the next task was to design a suit that would "enable the robot and the subject to sense the world," according to the lead robotic engineer on the project, Gordon Cheng of the Technical University of Munich. "The new skin sensors we developed have the same functionalities as human skin -- able to sense temperatures, pre-contacts, touch, vibration. The real innovation here is really not just the sensors themselves, but the methods we used to deploy them, self-organizing hundreds of these sensor cells automatically through advanced algorithms. Additionally, we are using these sensors inside the exoskeleton to monitor the comfort and movements of the subject."

Artist's Rendering
Walk Again Project
With a $20 million grant from the Brazilian government, Nicolelis pulled together a team of 166 neuroscientists, roboticists, technicians and laboratory staff from six countries in January 2013 -- just 18 months before the World Cup. "They are all my personal friends, most of them deciding to work for free," Nicolelis says of his ambitious group.

This spring, the final tests were done on the human exoskeleton in France, while in Sao Paulo, a group of eight people -- one of whom will be chosen for the milestone kick -- trained on a virtual-reality simulator, similar to how pilots train in flight school.
By the final week of May, the locomotion process felt "effortless," for all eight patients, according to Nicolelis.

"The big challenge was to overcome the skepticism," Nicolelis says of those who doubted the project would be ready by June. "We knew this would be possible. Most people thought this was a great idea but that it was not possible."

Nicolelis is now developing a more advanced version of the exoskeleton that will operate via a microchip implanted directly into the user's brain. A direct implant will collect more neuron data and sharpen the fluidity of movements. He expects the World Cup demonstration will generate the momentum needed to make devices using brain-machine interfaces commonplace in the near future. Eventually, he hopes, the suit will restore some self-reliance to stroke victims, car crash survivors, injured soldiers, or even elderly people at risk of falling.


"I have no doubt in 10 years that you'll see people walking in the streets with these devices," he says. "You basically show people that there is hope that this can come to fruition faster." He believes that in 30 years an exoskeleton will enable a victim of paralysis to compete in the Olympics.

"When you have a goal, deadline attached, that's worthwhile, you can gather the best minds in the world," Nicolelis says. "That's what we want to show the kids all over the world. Science can change the lives of a lot of people."
 







Real-Time Wastewater Analysis Shows What Drugs Are Being Used Where

$
0
0

Cocaine
U.S. Drug Enforcement Administration
When people take drugs, they end up in the water, either unchanged or broken down into specific metabolites. Increasingly, water can be tested to gauge how much drug use is going on in an area, and a new study shows that the level of illegal drugs being used in a community can be tested in real time, and potentially applied to help police narcotic use. 

Before the advent of this type of testing, dubbed "sewage epidemiology," drug usage was generally estimated by surveys, crime statistics, narcotics seizures and other self-reported information. But by analyzing the amount and type of drugs in wastewater, as done in this study, researchers can more accurately detect usage rates, find hotspots for abuse, and potentially measure the effectiveness of police countermeasures.

In the study, scientists searched for six illicit drugs (and their metabolites) in two wastewater plants, one serving a small and another a slightly larger community near Albany, N.Y. And drugs did they find, after testing the water each day for a week. In fact, the researchers detected cocaine in 93 percent of the untreated water samples. Based on the relative level of cocaine's metabolites, they determined that most of the drug ended up there via human excretion, rather than direct disposal. So it doesn't appear that a lot of people in Albany are flushing coke down the toilet in a panic. Drug levels remained relatively constant throughout the testing. 

Surprisingly, at least to me, morphine was found in 100 percent of the untreated water(!). The human body breaks down heroin into morphine and other chemicals, and this may be where the morphine is coming from, although the researchers don't specifically say in the study, published in Environmental Science and Technology. For what it's worth, the average concentrations of morphine found in the water "was 2.7–3.6 times lower than those reported earlier from the USA and the UK, but 3.0 times higher than those reported in Spain," the authors noted.

The study also found low levels of the designer drug 3,4-Methylenedioxyamphetamine (also known as MDA) and ecstasy, or MDMA

Testing for drugs in public water supplies has revealed a slew of interesting findings in the past few years. A study earlier this year found, for example, that in tests of water from a campus in Washington, “amphetamine levels go through the roof during finals,” University of Puget Sound researcher Dan Burgard told Environmental Health News. Other tests have revealed trends in various countries, as the site noted: 

  • In London, cocaine and ecstasy spike on weekends while methadone is used more consistently.
  • In Italy, cocaine use has declined while use of marijuana and amphetamines has increased.
  • In Sweden and Finland, people use more amphetamines and methamphetamines and less cocaine than other European cities. Also, in Finland, stimulants were more common in large cities.
  • In Zagreb, Croatia, marijuana and heroin were the most commonly found illicit drugs, but cocaine and ecstasy showed up more frequently on weekends. 
  • In Oregon, cocaine and ecstasy are more common in urban than in rural wastewater according to a 2009 study.

Another study published last month in the journal Addiction looked at drugs in the water in 42 European cities. And it found that people in Antwerp, Belgium, love drugs. The research "revealed traces of cocaine, amphetamines, cannabis, and ecstasy in Antwerp’s sewage—all at levels among the highest of [the] European cities tested," Bloomberg Businessweek noted








What's In Your Drinking Water?

$
0
0

What's in your water?
Data Visualization by Katie Peek; Pharmaceuticals data from Mitchell S. Kostich Et Al., 2014 in Environmental Pollution

In the 1970s, several studies turned up pharmaceuticals in treated U.S. sewage water, and drugs have been a known unknown in water supplies ever since. Recently, researchers at the Environmental Protection Agency tested 50 U.S. wastewater-treatment plants serving more than 46 million people for 58 common drugs. They found many of the meds, but thankfully at concentrations so low it would take years to drink a full dose. –Jessie Geoffray

*The study tested for generic compounds, but some brand names are listed here for easier identification.

Michelle Mruk

Parasites

About 750,000 people in the U.S. end up with diarrhea each year from drinking water contaminated by the Cryptosporidium parasite. In part, that’s because Crypto is resistant to the chlorine that water-treatment plants use to kill other microbes. Dozens of cities around the world are now installing massive ultraviolet-light arrays to zap the germ. As water flows through treatment facilities on its way to the tap, it passes through pipes specially outfitted with UV lamps. The UV light penetrates Crypto’s thick protein shell, damaging the pathogen’s DNA and rendering it harmless. –Peter Andrey Smith

Methane

For a study published in 2013, re-searchers tested 141 drinking-water wells across northeastern Pennsylvania. They found methane concentrations six times higher in wells close to hydraulic fracturing operations—contamination they propose is likely due to poor natural-gas-well construction. The Environmental Pro-tection Agency plans to release its own comprehensive study this year. –Jessie Geoffray

This article originally appeared in the June 2014 issue of Popular Science.

Read the rest of Popular Science’s Water Issue.









A Jetpack For Divers

$
0
0

Photograph by Hugh Gentry

On a windless day on the west shore of Oahu, Hawaii, I strapped a pair of propellers to my legs, walked into the surf, and disappeared beneath the surface. Without a single kick, I was racing over the sand, cutting through the water at an Olympic pace. It felt more like flying than swimming. I struck a Superman pose and sailed into the abyss.

Designed for Special Forces divers, the Patriot3 Jetboots are unique among personal propulsion devices because they’re hands-free and provide sea-creature-like agility. The two propellers, which hang from a waist harness and attach at the thigh, can send divers to nearly four knots. A lithium-ion battery worn at the small of the back could last up to four hours.

With the Jetboots—sort of a misnomer given how they’re normally worn—I was able to swim circles around turtles, blend in with a school of fish, and scare the life out of two divers plodding through the shallows. I’m certain they heard my crazed laughter as I flew by. To steer, I’d adjust the tilt of my head or arch my back to roll like a seal. With gills, I’d probably never want to surface.

Although it’s made for the military, the system has a number of civilian applications. Scientists could use it to traverse large areas of coral reef or track marine life. Salvage divers and documentarians could maneuver while retaining full use of both hands (and achieving greater control than with tank-mounted propulsion systems). And recreational divers like me could explore more reefs, caves, and wrecks. Turns out, a simple harness with two propellers and a battery can enable entirely new ways to see the ocean.

Right now those views come at a high price: The system can cost tens of thousands of dollars. But Patriot3 says it plans to create a cheaper, recreational version as soon as this summer. It may have less power, battery life, and durability, but it will no doubt offer a dose of the same fishlike experience I had that day doing barrel rolls in Hawaii.

To Go Even Deeper
Courtesy Nuytco Research Ltd/amnh.org

The Nuytco exosuit lets scientists work at depths up to 1,000 feet with unprecedented maneuverability. Divers pilot the suit with four thrusters, while 18 rotary joints enable movement. Oxygen tanks last for 50 hours, and a fiber-optic surface tether allows communication. The suit makes its first open-water expedition in July.

This article originally appeared in the June 2014 issue of Popular Science.

Read the rest of Popular Science’s Water Issue.








International Space Station Astronauts Will Watch The World Cup

$
0
0

Astronauts aboard the International Space Station recorded and posted this message yesterday, for the teams on the ground kicking off the World Cup today. The Expedition 40 crew includes people from Germany, Russia and the U.S., all countries that sent teams to Brazil this year. The German and the U.S. teams will play a match on June 26. Their spacefaring fans plan to watch the match from high above (on TV).

Curious how the space station compares in size to a soccer field? Of course you are. Luckily, NASA made this helpful illustration: 

illustration showing the International Space Station compared to a soccer field
ISS Wins
NASA







International Space Station Astronauts Will Watch The World Cup

$
0
0

Astronauts aboard the International Space Station recorded and posted this message yesterday, for the teams on the ground kicking off the World Cup today. The Expedition 40 crew includes people from Germany, Russia and the U.S., all countries that sent teams to Brazil this year. The German and the U.S. teams will play a match on June 26. Their spacefaring fans plan to watch the match—mission control will record it, and any other matches the astronauts request, and send them up.

Curious how the space station compares in size to a soccer field? Of course you are. Luckily, NASA made this helpful illustration: 

illustration showing the International Space Station compared to a soccer field
ISS Wins
NASA







Big Pic: The Sun Emitted Three Enormous Flares In 24 Hours

$
0
0

images of three X-class solar flares the sun emitted recently
Three Solar Flares June 10 and June 11, 2014
NASA/SDO/Goddard

The sun emitted three X-class flares—the most powerful type—over June 10 and June 11. Very sparkly. Each flare blasted enough radiation to cause blackouts in radio communications for about an hour on the sunlit side of Earth, according to the U.S. National Weather Service.

The sun, which goes through cycles of activity that last about 11 years, is now entering a solar maximum. The flares all occurred in a region of the sun that recently rotated toward Earth. Still, our home star's current liveliness is much weaker than other solar maximums on record, Space.com reports. Check out a more detailed explanation of the three recent flares there, and check out Discover magazine's ImaGeo blog for descriptions of some powerful past solar events.








Cell Phone Location Data Is Private, Court Rules

$
0
0

Disguised Cell Phone Tower
Look all I can see are trees here.
Wikimedia Commons

Even disregarding the content of a call, cell phones reveal a wealth of information about the person making the call. Called "metadata," that bundle of other information can include the time the call took place, the call duration, the company that carried the call, and the cell towers that transmitted the call, giving a rough approximation of the callers' physical locations. Last summer news broke that the U.S. government was storing cell phone metadata. Yesterday, the Eleventh Circuit Court of Appeals ruled in USA v. Quartavious Davis that Fourth Amendment protections against against unreasonable searches and seizures and the issuing of warrants without probable cause extend to cell phone location data.

The case concerns Quartavious Davis, convicted of armed robberies after the police used cell phone location data to place him in the vicinity of the other robbers. Police obtained this location information from the cell phone companies through court order, which has a much lower threshold for reasonable cause than that required for a warrant. 

Here's the crucial nugget at the heart of the decision:

Supportive of this proposition is the argument made by the United States to the jury. The prosecutor stated to the jury “that obviously Willie Smith, like [Davis], probably had no idea that by bringing their cell phones with them to these robberies, they were allowing [their cell service provider] and now all of you to follow their movements on the days and at the times of the robberies . . . .” Just so. Davis has not voluntarily disclosed his cell site location information to the provider in such a fashion as to lose his reasonable expectation of privacy. 

In short, we hold that cell site location information is within the subscriber’s reasonable expectation of privacy. The obtaining of that data without a warrant is a Fourth Amendment violation.

The decision is set up by a Third Court ruling from 2010.

The Third Circuit went on to observe that “a cell phone customer has not ‘voluntarily’ shared his location information with a cellular provider in any meaningful way.” That circuit further noted that “it is unlikely that cell phone customers are aware that their cell phone providers collect and store historical location information.” Therefore, as the Third Circuit concluded, “when a cell phone user makes a call, the only information that is voluntarily and knowingly conveyed to the phone company is the number that is dialed, and there is no indication to the user that making that call will also locate the caller.” Even more persuasively, “when a cell phone user receives a call, he hasn’t voluntarily exposed anything at all.”

Much of the legalese around this is tied up both in privacy precedents and an understanding of what information is private and what is held by third parties. As for the technology, location data built up over the course of a day can reveal in aggregate much about an individual that they may wish to keep private. Last year, MIT researchers published a study showing it is possible to identify people with 95 percent accuracy using just four points from a location tracking cell phone. 

While the Davis case sets an important precedent, the appeals court notes in their ruling that because there is no evidence the police "evidenced anything other than good faith," the court does not see fit to reverse their error. Instead, USA v. Quartavious Davis provides a ruling for the future that asserts fourth amendment protections over cell phone location data. Should this precedent hold, in the future police will need warrants, not court orders, to obtain such information.








Viewing all 20161 articles
Browse latest View live




Latest Images