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发表于 2014-12-16 20:28:23
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Entrepreneur Changes Life in Uganda by Turning Waste Into Fuel
Emerging Explorer Sanga Moses tackles social problems and deforestation with cooking briquettes.
Susan Daugherty Published December 15, 2014
[Time 2]
Sanga Moses grew up in bare feet in a small Ugandan village of thatched roofs that lacked electricity. Yet he became his clan's first college graduate and took a bank job in Kampala.
Returning home for a visit from the Ugandan capital in 2009, he met his 12-year-old sister on the road. "She stood there crying, with a heavy bundle of wood on her head," Moses remembers. "She was upset because, like most rural girls, she missed days of school each week searching for fuel wood."
"My sister … was losing the only opportunity she had to make her life better—education."
It wasn't the only change Moses noticed in his hometown. "When I was young, our home was surrounded by national forests," he says. "Now all those trees are gone, and children must walk longer and longer distances to gather wood."
Searching for a solution to problems born of burning wood, Moses quit his job and began learning everything he could about renewable resources. Eventually he came across the increasingly popular practice of turning organic waste into fuel.
"I looked out my window and saw a huge pile of sugar cane debris," he says. "Uganda is primarily agricultural, but farm waste is just abandoned."
So Moses began working with engineering students to design kilns and briquetting machines.
Four years later, 2,500 farmers use his kilns to turn farm waste—coffee husks and waste from sugar cane and rice—into charcoal. A company that Moses founded, called Eco-Fuel Africa, buys the char and turns it into briquettes for cooking that burn cleaner and cost less than wood.
The company takes those briquettes to market, providing fuel for more than 19,000 Ugandan families.
"Burning fuel wood not only destroys Uganda's trees," Moses says, but it also affects "the health and educational opportunities of our poorest people.
"We're giving them an alternative."
[310 words]
[Time 3]
Wood Burning Takes a Toll
The problems that wood burning created for Moses's family and in his hometown can be seen across sub-Saharan Africa. Eight in ten people in the region depend on wood to cook and to heat their homes. As more forests are destroyed to feed that demand—in Uganda, 70 percent of protected forests are gone—families must walk more miles every day to buy increasingly scarce and costly wood.
Families in the developing world spend up to 40 percent of their income on cooking fuel. Besides leaving children with less time for education, it means that poor farmers are less able to afford fertilizer, causing harvests to suffer and malnutrition to rise.
And wood burning takes a huge toll on human health, creating smoky indoor air that leads to respiratory diseases that kill more women and children each year than HIV/AIDS.
Moses's cleaner-burning green charcoal reduces indoor air pollution and has already saved more than three million dollars in energy-related expenses for Ugandans. "Families use that money to pay school fees for their children, afford three meals a day, and finance new income-generating activities," he says.
Indeed, farmers who work with Eco-Fuel Africa have tripled their incomes by selling char from kilns. The coarser, leftover char is used as fertilizer, which can increase harvests by more than 50 percent and create surplus crops to sell at market.
Moses's group also battles deforestation, investing profits into planting 12,000 new trees and partnering with local schools to make reforestation part of environmental education.
"Today young people who graduate from college come to us and say, 'I don't care how much you pay me; I want to join you because I believe so strongly in what you do,' " Moses says.
Eco-Fuel Africa also looks for employees among Uganda's widows and single mothers, who often struggle after husbands die of HIV/AIDS.
"They value the opportunity to become machine operators and retailers," Moses says, "bringing unbelievable commitment, dedication, and hard work to our project."
"Many times when I visit villages," he continues, "a woman will grab my hand and say, 'Six months ago I could barely feed my family. Now I've been able to enroll my daughter in school and buy a solar panel and mobile phone.' "
Eco-Fuel Africa has received interest from Rwanda, Kenya, and Zambia, but Moses wants to "get our business model right and then expand to new countries."
Funding from National Geographic recently helped the organization develop a briquette-making machine that can run without electricity, so it's workable in remote rural areas.
"Now we can micro-franchise in villages far off the power grid," Moses says. "We identify entrepreneurs, supply training and support, and provide technology on a credit basis so they can start sustainable businesses, create jobs, and meet local energy needs."
All while improving Ugandans' health—and saving their forests.
[476 words]
Source: National Geography
http://news.nationalgeographic.com/news/2014/12/141215-sanga-moses-uganda-energy-wood-burning-fuel/#at_pco=cfd-1.0&at_ab=-&at_pos=11&at_tot=4&at_si=undefined
Twisted, Tangled and Turbulent: Magnetic Fields in the Milky Way
by Nadia Drake
[Time 4]
If the Milky Way were strewn across a swath of silk and set aflutter in the breeze, it would look something like the rippling images in the gallery above.
But these are representations of our home galaxy, produced from nearly 1,500 days of observations made by the European Space Agency’s Planck satellite. Each of the images above corresponds to a numbered section in this map of the Milky Way:
The colors represent the density of galactic dust emission, from a sparse blue to intense red, and the ripples reveal the orientation of the Milky Way’s magnetic field. There are filaments and clouds, regions of chaos and cohesion, hints about how matter and magnetism interact to shape the interstellar medium, and clues about the mysterious origin of magnetic fields.
Combined, the swirling dust, hot stars, and explosion remnants look a lot more like a post-Impressionist painting than your typical astronomical data dump.
But these aren’t just pretty pictures.
“These vivid images are like a storyboard,” says astrophysicist Marc-Antoine Miville-Deschenes of the French National Center for Scientific Research, who made the images using data gathered by Planck. “For us, they are instrumental in revealing the role of the magnetic field in the way matter is organized, and in how matter evolves toward the formation of stars.”
Launched into space in 2009, the Planck satellite spent nearly 4.5 years trying to read the oldest, faintest signatures sewn into the fabric of the cosmos. These inscriptions include the remnants of radiation produced during the Big Bang, and clues to the composition of matter in the universe. Last week, at a meeting in Ferrara, Italy, Planck scientists began to slowly reveal their latest data, which will be released to the public on Dec. 22.
Included in those data are these images of the galactic magnetic field. Scientists can’t see magnetic fields, but they can carefully study the orientation of light emitted by dust grains in the Milky Way. Most of these grains aren’t spherical, but are elongated, and they tend to align with local magnetic fields. “Think of them as tiny magnetic rice grains,” says astronomer Bryan Gaensler of The University of Sydney.
[358 words]
[Time 5]
Scientists use the orientation of light emitted by dust to infer the direction of local magnetic fields. And because the Planck instruments are so sensitive and stare at the whole sky, they’re treating scientists to a better view of galactic magnetism than ever before.
“In the past, we’ve had lots of individual measurements at particular points on the sky,” Gaensler says. “It’s like before we were looking at the sky through a black curtain with a lot of pinholes in it, but now the curtain has been dropped.”
The images reveal that while the Milky Way’s magnetic field across large scales is ordered and smooth, it’s a tangled, turbulent mess on smaller scales. Local fields are perturbed by such things as stellar winds, explosions, and turbulence, which disrupt long-range symmetries and can have dramatic effects on processes like star birth and cosmic ray acceleration. Though scientists have known about these incongruities since the 1940s, they are now on the cusp of being able to clearly see what’s going on.
“These images are not about cosmology, they are about the complex dynamical processes that turn interstellar matter into stars and back,” Miville-Deschenes says. “The cycle of matter and the way stars form in a galaxy like the Milky Way is not well understood.”
And, those silky ripples could also tell Gaensler and his colleagues something fundamental about where magnetism came from in the first place – a question that is far from being resolved. Did it arise during those first few moments after the Big Bang? Was it cooked up in stars and black holes later on? Generated by a primordial cosmic battery?
“The shape of the Milky Way’s overall magnetic field is a direct descendant of the magnetic cloud from which the Galaxy formed, billions of years ago,” Gaensler says. “Which is in turn a key clue about where all the magnetism in the Universe came from in the first place.”
[320 words]
Source: National Geography
http://phenomena.nationalgeographic.com/2014/12/08/magnetic-milky-way/#at_pco=cfd-1.0&at_ab=-&at_pos=15&at_tot=4&at_si=54900bc8f90addb4
Microbes exploit their killer
Triclosan promotes antibiotic resistance
By Beth Mole December 15, 2014
[Time 6]
25 Microbes have turned our pharmaceutical weapons into allies. This year, triclosan, an antimicrobial agent, topped the list of chemical traitors, aiding rather than deterring germs.
Leaked from products such as toothpaste and hand soap, low doses of triclosan promote drug resistance in germs that cause difficult-to-treat infections. In the environment, the chemical can disrupt hormone regulation in some animals, such as fish. (Data are lacking on health effects in humans.)
Despite the ongoing battle against antibiotic-resistant microbes, triclosan remains omnipresent in household and personal care products. Humans take up the anti-microbial agent by ingesting it or absorbing it through skin. Washed down the drain, triclosan amasses in sewage and seeps into the environment.
In people, the chemical shows up in blood, urine, breast milk, umbilical cords and snot. The health risks of prenatal doses of triclosan are unknown. In the nose, however, researchers found that triclosan-laced snot helps Staphylococcus aureus bacteria invade the body. Such invasions increased the risk of staph infections, which can cause pneumonia.
In wastewater treatment plants, triclosan can sabotage the microbial cleaners responsible for breaking down sewage, killing off some beneficial microbes and spurring drug resistance in others.
Some of the 100 metric tons of triclosan that enters U.S. sewage plants each year lingers after treatment. Treated waste-water and sewage-based fertilizers can then spread the antimicrobial chemical. When such treated water is used on farmland, small amounts of triclosan accumulate in vegetables.
The U.S. Food and Drug Administration is reviewing the use of triclosan in personal care products. But some legislators and manufacturers aren’t waiting. In May, Minnesota banned triclosan from certain products, effective in 2017. And Johnson & Johnson and Procter & Gamble plan to remove the antimicrobial agent from their products.
[288 words]
Source: Science News
https://www.sciencenews.org/article/year-review-microbes-exploit-their-killer?tgt=nr
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