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Tappan reads the bill for the establishment of the Smithsonian Institution. Mr. Choate praises Mr. Tappan for introducing the bill because the matter of establishing the Smithsonian Institution was long overdue, however, Choate offers a different view of the form the institution should take. There is some debate and further consideration is postponed.
When Army scientists mixed some of their new aluminum-based nano-powder in water, the results were startling.
“It bubbled very similarly to an Alka-Seltzer tablet, but probably more violently,” says Kristopher Darling, a materials scientist at the U.S. Army Research Laboratory (ARL) in Maryland.
The scientists realized that the powder was somehow splitting water and releasing hydrogen, an exciting discovery given hydrogen’s usefulness as a fuel. But when they mixed the powder with urine, things got really exciting. The bubbling, already vigorous, became even more lively, suggesting that the powder was extracting more hydrogen from urine than from the water. Later measurements showed the reaction rate was about double.
Why were Army scientists mixing aluminum nano-powder and pee, you might ask? Well, the mission of the laboratory is to develop materials that could one day benefit soldiers in the field.
“How do you supply energy to away teams that are gone for an extended period of time?” Darling asks. “So we began to look at how do you utilize existing fluids that the solider would have on them?”
The team is not yet sure why the aluminum powder produces more hydrogen from urine than from water. It could have something to do with the electrolytes in urine, or differences in the pH. But what they do know is that the ability to produce hydrogen in the field could have dramatic benefits.
“The applications could be anywhere you need power,” says ARL scientist Scott Grendahl.
Soldiers could carry aluminum nano-powder to mix with water or urine to juice up a fuel cell. The powder could be painted on the inside of tanks to, when wetted, provide a power boost when fuel ran out. It could be 3D printed into parts for drones or robots that could “self-cannibalize” when running low on power by dipping themselves in water.
The powder could also potentially be produced in the field through gathering things like aluminum cans and blown-up vehicles. If this were successful, then soldiers in theory could make fuel out of nothing but scavenged materials and their own urine.
This is a big deal, as a large percentage of soldier deaths in the Middle East happen during fuel supply convoys. This fact has given the U.S. military a major incentive to create new, more efficient fuel technologies.
Hydrogen has long been touted as a green fuel. But it’s not simple to transport, as it needs to be either pressurized or liquified first. Producing hydrogen from water using aluminum is not new. But these processes have always needed a catalyst, which traditionally means adding acids, bases or additional energy, or using high temperatures. Some of these catalysts can be toxic and polluting. This new process, by contrast, simply needs the aluminum alloy nano-powder and a water-based liquid—water, sports drink, urine, saliva. The nano-powder is made of tiny grains of aluminum and other metals arranged in a nano-pattern.
“We have no catalyst, our byproducts are inert and nontoxic, and it’s very efficient,” Grendahl says.
The team is currently in the process of patenting their invention. The next steps will be optimizing the process and scaling up. The team can currently make the powder in kilogram quantities, and expects it will be relatively simple and inexpensive to make larger amounts. After that, other ARL teams will get involved to work on applications. There has also been interest from universities and private industry. This isn’t surprising, given how useful on-demand cleanly-produced hydrogen could be for things like hydrogen-powered cars. But, as experts caution, it’s not clear yet how the process will work outside of the lab.
If it’s successful, the soldier of the future may be powering his or her flashlights and communication devices with nothing but empty soda cans and pee. Talk about recycling.
When I first read about the Okefenokee Swamp as a 10-year-old boy, I immediately wanted to go. I pictured a muddy jungle perfect for exploring; a flooded forest filled with snakes and alligators. But for some reason, my parents weren't eager to plan a family vacation to a soggy wilderness on the border of Georgia and Florida.
Nearly two decades after I first heard of the swamp, I set off in March to canoe across it with four friends. I soon found that the swamp was much more varied than my childhood image. Habitats in Okefenokee range from shallow lakes to sandy forests. “Unless you see all sides of the swamp, you really don't see the swamp,” explains Grace Gooch, a ranger at the refuge. Our three-day journey would hit the swamp's highlights. A true backwoods experience, it was unlikely we would run into other people after entering the swamp’s designated wilderness area.
The Okefenokee is an enormous peat bog 38 miles long by 25 miles wide, created 7,000 years ago when a wide depression filled with decaying vegetation. Okefenokee means “land of the trembling earth” in Choctaw, a reference to the quivering ground of especially boggy areas. The Okefenokee National Wildlife Refuge was officially established in 1937 to preserve one of America’s oldest freshwater systems, an important habitat for an abundance of plants and animals that live in its 400,000 acres. It is the largest wildlife refuge in the East.
We began our journey on a sunny South Georgia morning, entering the swamp via an old peat mining canal at Kingfisher Landing, with water blackened by tannic acid from decomposing plants. From the forest we paddled into a series of small lakes where the views opened up into a wet version of the Great Plains, dotted with lily pads and grasses. Signs marked a cleared canoe trail that meandered through the plants.
The big-sky vistas were at odds with the image of a deep, dark swamp. But about a fifth of the swamp is considered prairie, flooded on average by about a foot of water. Natural fires burn forest during dry spells, creating lakes and marshy areas that are perfect hunting grounds for wading birds. Here, five-foot-tall sandhill cranes poked their long, skinny bills among the grass, while egrets and ibises flew overhead.
It wasn’t long before I encountered my first gator, an eight-footer sunning itself a few yards from my canoe. With tough, leathery scales, a spiked tail and massive head, it looked like it wandered out of Jurassic Park. But the alligator barely reacted to my presence. Over the course of the trip, I learned that gators do their best to avoid confrontation. Most of the dozens I passed either stayed still or swam away slowly.
Image by Kenneth Fletcher. Soon after the writer set off to canoe across the Okefenokee Swamp, he learned it was much more varied than his childhood image. Habitats in Okefenokee range from shallow lakes to sandy forests. (original image)
Image by Kenneth Fletcher. The Okefenokee Swamp is an enormous peat bog 38 miles long by 25 miles wide, created 7,000 years ago. (original image)
Image by Kenneth Fletcher. Over the course of the trip, the writer learned that alligators do their best to avoid confrontation. Most of the dozens he passed either stayed still or swam away slowly. (original image)
Image by Kenneth Fletcher. The water at Okefenokee Swamp is blackened by tannic acid from decomposing plants. (original image)
Image by Kenneth Fletcher. Despite the absence of any sign of people, the swamp teemed with life. At night, the stars reflected brightly off the inky water. (original image)
Along the canoe trail, large clumps of knee-high pitcher plants grow thickly on patches of bright green sphagnum moss. The plants have a unique adaptation that allows them to thrive in the nutrient-poor soil. The reddish leaves curl into tubes that lure insects that fall into digestive enzymes in the bottom, feeding the plant.
After paddling eight miles, we reached our first campsite; a wooden platform a few feet above the water. It sat on the edge of a lake filled with purple lily pads and yellow flowers. The sun sank low, and the orange sky silhouetted a patch of trees dripping with curly beards of Spanish moss.
I was struck by the absence of any sign of people, but the swamp still teemed with life. As the sky darkened, I heard an orchestra of night sounds. Pairs of cranes sang together, a trumpeting that reverberated across the swamp. Choruses of frogs chimed in. Night fell, and owls hooted and howled from trees dotting the prairie. The stars reflected brightly off the inky water while the Milky Way glowed in the sky. I was content to listen and trace the stars in the constellations.
The next day, the canoe trail narrowed until it was barely wider than the boats as we entered a thick tangle of vines, bushes and trees. Suddenly, something torpedoed out of the water and hit me. An 18-inch chain pickerel fish rolled off my lap and lay flopping in the bottom of the canoe.
We pushed through flooded forest until we finally reached dry ground. Floyd’s Island is a sizeable stand of oaks, pines and magnolia in the middle of the swamp. I spotted a small herd of deer grazing on the sandy soil. An old cabin stood near the boat landing, built in the early 20th century as a hunting retreat for owners of the Hebard Cypress Company, which logged the swamp.
On our last day in the Okefenokee we canoed on the Suwanee Canal, built more than 100 years ago to drain the swamp and make way for sugarcane, rice and cotton plantations. The canal was never completed, and cypress logging became the swamp’s major industry until the refuge was established and prohibited commercial enterprise.
On my trip down the canal, I spotted a new alligator every few minutes, sunning amid fallen logs. Cypress trees lined the banks, nearly lost in the thick, gray tendrils of Spanish moss. The wide, straight canal eased me back into civilization, leading me to the refuge visitor's center.
After leaving the swamp, I called Jackie Carter, who clears canoe trails in the refuge and whose family has lived on the edge of the swamp for generations. He considers the Okefenokee one of the most beautiful places on earth, and says all of us can learn from it. “It teaches you a lot about humility. The swamp is always teaching you something,” he told me. “People get in there and feel the peacefulness and quiet.”
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You’ve heard of the “Mona Lisa”, “The Last Supper” and “Vitruvian Man,” but did you know that Leonardo da Vinci was also an early innovator in the science of aviation? Between 1505 and 1506, the legendary polymath created his “Codex on the Flight of Birds,” an 18-page notebook containing detailed observations on aerodynamics. A digitized version of the d0cument went to Mars on the Curiosity Rover in 2011. This September, the original codex comes to the National Air and Space Museum.
From September 12 to October 22, 2013, ”Codex on the Flight of Birds” will be displayed in the gallery that houses the 1903 Wright flyer—though Leonardo preceded the Kitty Hawk pair by four centuries. According to Peter Jakab, chief curator of the Air and Space Museum, the codex contains the “seeds of the ideas that would lead to humans spreading their wings. . . . In aeronautics, as with so many of the subjects he studied, he strode where no one had before.” Leonardo’s notes even “hinted at the force Newton would later define as gravity.”
The exhibition will feature “interactive stations” allowing visitors to flip through the pages of the codex. This landmark work, which has rarely left Italy, is on loan from the Royal Library of Turin as part of the Year of Italian Culture in the United States.
Latest issue consulted: No.91 (Mar. 2009).
Per publisher letter, as of no. 91 (Mar. 2009) some content will be included in Scottish birds and publication will no longer be available separately.
Temperatures and environmental conditions are changing, causing the spread of disease to shift. How those changes and shifts will play out, however, is the subject of debate. It’s impossible to build a computer model that perfectly mimics the real world and can thus predict, say, where mid-latitude regions will become warm enough for tropical diseases to thrive or wet enough to enhance the spread of water-borne pathogens. But research does suggest that—similar to shifts in animal and plant distributions as climate changes—some places will see rates of certain diseases drop, while others will see an increase or introduction of those diseases.
Shifting patterns of disease do not apply only by latitude, however. Just as how the distribution of desert cacti is slowly creeping into Arizona's hills or how lowland insects are moving into mountains in Borneo as climate warms, diseases can also broaden their distributions by reaching higher and higher elevations. And according to a new study published by American, British, Ethiopian and Colombian researchers in Science, it’s already happening.
The authors of the study turned their attention specifically to malaria, which infects an estimated 300 million people each year. Malaria might be particularly susceptible to changes in distribution due to warmer temperatures, they explain, because the Anopheles mosquitoes that carry the malaria parasite can only live in warm environments.
The researchers focused on the highlands of western Colombia (50 to 2,700 meters) and central Ethiopia (1,600 to 2,500 meters), which historically have been cool year-round but have experienced a flux of warmer and cooler seasons in recent years. To see how malaria might or might not have been affected by those climate variations, they compared records of malaria incidence from 1990 to 2005 in Colombia, and from 1993 to 2005 in Ethiopia, with temperature data from each of those years.
In warmer years, they found, malaria incidence did indeed occur at significantly higher elevations than in the cooler years. In Ethiopia’s Debre Zeit region, for example, an increase in 1ºC corresponded to an average of more than 2,100 additional cases during the transmission season, from September to December.
"This is indisputable evidence of a climate effect," said Mercedes Pascual, a theoretical ecologist at the University of Michigan and co-author of the study, in a statement.
She and her colleagues predict that these results would also apply to other countries and regions that suffer from malaria, although studies will have to be undertaken in those places to confirm that assumption. "The main implication is that with warmer temperatures, we expect to see a higher number of people exposed to the risk of malaria in tropical highland areas like these," Pascual added.
A permanent 1ºC temperature change in Ethiopia could mean three million more malaria cases per year in people under 15-years old alone, the authors estimate. Around 43 percent of the country's population currently lives in rural areas historically protected from malaria due their elevations of 1,600 to 2,400 meters, but which now fall within the potential danger zone for hosting the disease as climate warms.
"Our latest research suggests that with progressive global warming, malaria will creep up the mountains and spread to new high-altitude areas,” said Menno Bouma, a clinical lecturer at the London School of Hygiene & Tropical Medicine and co-author of the study. “And because these populations lack protective immunity, they will be particularly vulnerable to severe morbidity and mortality."
Malaria’s shifting distribution is certainly a cause for alarm. According to the United Nations, the disease causes around 2 million deaths annually—most of which are children—and acts as a significant burden to countries, keeping poor regions poor by reducing worker productivity and thus economic growth.
The study authors point out that their research is a heads-up about what will likely become an even greater problem in the future. They note that nonprofits, governments, and other groups interested in curbing the spread of malaria will need to establish intervention methods in places where they were previously not needed before, including at higher altitudes. Mapping where malaria may strike under different regimes of climate change "should further contribute to the early warning of epidemics and assist global malaria elimination,” they write.
The captain of the small fishing boat didn’t exactly instill confidence in his passengers. “The last two photographers got sick,” he told us helpfully as we prepared to leave the port of tiny Block Island, off the coast of slightly-bigger Rhode Island. The photographer next to me, with another news organization, fiddled nervously with his equipment, a motion sickness patch on his neck. I, too, had taken a precautionary Dramamine.
We were traveling a mere three miles southeast of the island, where the last of five 560-foot-tall wind turbines was being erected in the shallow coastal waters. Designed by General Electric for a project owned by Providence-based Deepwater Wind, the stalwart, 6-megawatt machines constitute the first offshore wind farm in the United States—and we were going to see it up close.
It was a clear August day, and the water was relatively calm. Eric Crucerey, the Block Island Wind Farm project director for GE Renewable Energy, and I looked through the windshield as the four completed turbines came into view. Crews, he said, had been working nonstop since early August, with a few delays.
“We had to stop several days due to high winds,” said Crucerey, who has been in charge of transporting and installing the five GE Haliade turbines. The hold-up, he said, was a contradiction: of course the project’s organizers want strong winds to produce energy. Just not in this phase, as it complicates the installation.
Shipping the parts of the turbines to Block Island was a beastly task in itself. Manufactured in a GE factory in Saint-Nazaire, France, the five, 400-ton nacelles—machines with all of the turbines’ generating components—crossed the Atlantic on a large vessel called the Brave Tern. The 15 blades, weighing 27 tons and measuring 240 feet each, first traveled by highway with a police escort on a special trailer from the factory in Denmark where they were made to a port where they were shipped to Aviles, Spain. There, they joined up with the towers and continued on to Providence.
Image by LM Wind Power. A 240-foot blade for a turbine at the Block Island Wind Farm travels down a Danish highway on a special trailer. (original image)
Image by LM Wind Power. The transportation crew had to build its own makeshift roads in order to maneuver some turns on the way to the port. (original image)
Image by Deepwater Wind/GE. The 400-ton nacelles were manufactured in a GE factory in Saint-Nazaire, France. (original image)
Then came the heroic feat of assembling the turbines. On site, the Brave Tern transformed into a construction platform. The vessel jacked up above the water’s surface on four sturdy legs rooted in the sea floor. Throughout this month, crews positioned the barge at each “jacket,” a bright yellow steel base planted in the seabed and rising out of the water. These foundations for the turbines were laid last year—a “steel in the water” milestone for the offshore wind industry in the United States. Cranes on the Brave Tern’s deck hoisted parts hundreds of feet into the air, and, piece-by-piece, crews erected the turbines. The final blade was added to the fifth turbine last Thursday with a giant gripper dangling from a crane.
The Department of Energy has estimated that there is the capacity to generate more than 4,000 gigawatts of electricity—four times the existing electric system—from offshore wind along the coast of the U.S. and the Great Lakes. Earlier this month, Massachusetts Governor Charlie Baker added some momentum to the cause when he signed legislation that requires electricity distributors in the state to reach 1,600 megawatts (a commitment higher than any other state) of offshore wind energy by 2027.
The 30-megawatt Block Island Wind Farm is miniscule compared to Europe’s offshore farms. But it gets the job done: Each turbine can generate enough electricity for up to 5,000 homes. “But because of what they call the ‘capacity factor,’ which basically allows for the fact that the wind doesn’t blow all of the time, we think of these five machines as being able to supply electricity for 17,000 homes,” said Tim Brown, public affairs leader for GE Renewable Energy. The 125,000 megawatt-hours of electricity produced each year should meet 90 percent of Block Island’s power needs.
Undersea electric cables connect the five turbines to a new substation on Block Island, and National Grid, a utility company providing electricity and natural gas to Rhode Island, New York and Massachusetts, laid a cable from the island to mainland Rhode Island. Deepwater Wind agreed to initially sell electricity to National Grid at a rate of 24.4 cents per kilowatt-hour.
The $300 million farm’s relatively modest size ultimately helped it succeed. Others, like the 130-turbine Cape Wind project off Cape Cod, have been stymied in part by vocal residents who see the metal behemoths as an eyesore. The fact that Block Island has never been connected to the energy grid also makes it a favorable spot for a wind farm. Homes and businesses on the island currently get all of their electricity from generators fueled by diesel shipped from the mainland—a method that is very expensive. Deepwater Wind estimates that the new farm will ultimately reduce electric rates on the island by 40 percent.
As our fishing boat bent around the first turbine, I tried not to think about what I had for breakfast. Everyone’s heads tilted back to take in the hunk of steel before us. Crucerey explained that crews of up to 25 people are distributed to each machine in the morning for 10 hours of work. Their boats approach the turbine carefully, and the crewmembers start their day with a vicious workout: climbing 65 feet up a ladder to the steel jacket. Inside the tower, there is an elevator that ascends more than 300 feet (the equivalent of around 30 stories) to the nacelle, which can accommodate six people. A helicopter pad is attached to the nacelle in case the turbine needs to be serviced in conditions too rough to send technicians by boat.
Maneuvering the costly parts of giant machines on the water is difficult. “When we are offshore, everything is very complex,” Crucerey said. “We have to be prepared for anything. To have always in mind, if something happened, what are we going to do?”
The crew went through a number of safety trainings, including a rescue activity that involved jumping, with a controlled cable system, from the helicopter pad.
“I did it,” Crucerey said, with a smile.
In the next weeks and months, crews will be testing the turbines. The machines are expected to be operational by October or November.
“This project is a very important symbol of the fact that tangibly offshore wind can work in the U.S.,” Brown said. “It won’t be a theoretical debate. People will see it in the water, they will see it working, and they will see it supplying electricity.”
The world's largest living lizard is the Komodo dragon (Varanus komodoensis), a type of "varanid" lizard. Despite the fact that Komodo dragons are very interesting and widely known, there is a lot missing in our understanding of their natural history. Now a study of fossil evidence from Australia, Timor, Flores, Java and India shows that Komodo Dragons most likely evolved in Australia and dispersed westward to Indonesia. Some of the fossils that have been studied are newly described, including a species from Timor, and some are material known for a long time.
Here's the most important finding: The two main hypotheses for the origin of the Komodo dragon have been brought into question and replaced with a new and better hypothesis.
It was previously thought that one of the best explanations for the large size of the Komodo dragon was the "island effect." On islands, some animals may get bigger because of an increasing reliance on lower quality food found on island—the larger body size accommodates a gut that can process the food. In other cases, animals get smaller for a variety of reasons. But mostly, islands have strange effects on many species because evolution in the small population can proceed very rapidly. The animals that are confined to islands for long periods of time may simply evolve into food niches (which often relate to body size) that their sister species on the mainland did not experience.
A second hypothesis for the large size of Komodo dragons is that they were once specialists in the hunting of the pygmy Stegodon (a small elephant). This is a sort of indirect island effect. The Stegodons got small because they lived on islands, and the lizards evolved to be large enough to eat them.
Both of these hypotheses—island effects and specialist Stegodon hunter—now seem unlikely.
The new research indicates that Komodo dragons were really part of a distribution of related species of really large lizards across the region, including Australia. In fact, in comparison to some of these other lizards, Komodo dragons are kind of small.
In the words of Scott Hocknull, Senior Curator of Geosciences at the Queensland Museum and author of the paper, Australia is a hub for lizard evolution:
The fossil record shows that over the last four million years Australia has been home to the world's largest lizards, including a five meter giant called Megalania (Varanus prisca). Now we can say Australia was also the birthplace of the three-meter Komodo dragon (Varanus komodoensis), dispelling the long-held scientific hypothesis that it evolved from a smaller ancestor in isolation on the Indonesian islands. Over the past three years, we've unearthed numerous fossils from eastern Australia dated from 300,000 years ago to approximately four million years ago that we now know to be the Komodo dragon. When we compared these fossils to the bones of present-day Komodo dragons, they were identical. This research also confirms that both giant lizards, Megalania (Varanus priscus) and the Komodo dragon (Varanus komodoensis), existed in Australia at the same time.
This research was published Tuesday in the Open Access journal PLoS ONE. You can access this paper here.
Citation: Hocknull SA, Piper PJ, van den Bergh GD, Due RA, Morwood MJ, et al. (2009) Dragon‚Äôs Paradise Lost: Palaeobiogeography, Evolution and Extinction of the Largest-Ever Terrestrial Lizards (Varanidae). PLoS ONE 4(9): e7241. doi:10.1371/journal.pone.0007241