skip to main |
skip to sidebar
When the time came for chemical ecologist Walter Leal to test whether humans make a natural odor that attracts mosquitoes, Leal himself was the first to volunteer.
"I measured my own levels," Leal said. "I thought I would set a good example. If you do it first, then others won't be scared."
In truth, there was little, if any, reason to be frightened. The scientists were looking only for the substance itself, not trying to find out whether the compound would lure the insects to a blood meal. And the researchers found it--nonanal, a substance made by humans and birds that creates a powerful scent that Culex mosquitoes find irresistible.
Leal only had to roll up his sleeve. His colleagues laid a syringe-like instrument next to his skin, and then wrapped his arm in aluminum foil to keep the environment confined. After an hour, the tip of the syringe was injected into a special machine to see if the syringe contained nonanal and, if so, how much his body had produced.
Plenty, as it turned out. "It's there. I have lots of it," he said. "I think I released 20 nanograms in an hour. It was high."
Those results may well explain what happened to him two years ago in Mexico during a beetle hunting field trip when--despite extensive precautions--mosquitoes went after him with a vengeance.
"There were so many mosquitoes, I could not believe it," Leal recalled. "I sprayed Deet everywhere, including in my hair. The next morning, I realized they'd gone through my socks, and bitten me like crazy--and I had on thick socks. If you forget about one particular spot, the mosquitoes will find it--and go in. They'll go through anything, even jeans, as long as they know there is a blood vessel on the other side. They can sense the heat."
Nevertheless, while most people avoid insects, especially biting ones, Leal, a professor of entomology at the University of California (UC) at Davis, searches for them with enthusiasm.
"The diversity and physiology of insects is so remarkable," he said. "One insect is so different from another--that's what makes them so interesting."
In his research, Leal is best known for his work on insect sex pheromones (chemical messengers) and the chemical ecology and communication of insects, all with potential applications for pest control. He figured out why mosquitoes are repelled by Deet--they really hate its smell--and he has identified and synthesized complex pheromones from such insects as scarab beetles, true bugs, longhorn beetles, moths, the naval orangeworm and even cockroaches.
"I can work with any insects, including the cockroach," he said. "They are not so nice. They eat almost everything, so it is impossible to make an environment not accessible to them. And it's hard to kill them--they have sensors for air, so when you try to hit them, they detect the movement and get away. I have heard people say that they eat cockroaches, just to show they're not so bad. I'm not one of them."
His personal favorite? Scarab beetles. "They are so beautiful and elegant," he said. "But it's very difficult to work with them here in California because many of the species are invasive. So we can't have them in California."
Leal grew up in Recife, Brazil, where his sister and three brothers still live. "I am the only one who left," he said. He made his first trip to America in 1976 as a student to help broadcast news stories about the Brazilian soccer team during the Bicentennial World Cup. "I still have that passport," he said.
He became interested in environmental issues in college, and received his bachelor's degree in chemical engineering from the Federal University of Pernambuco in Recife. He earned his two advanced degrees from universities in Japan, where he spent 16 years, most of them working for the Japanese government. He earned a master's degree in agricultural chemistry from Mie University in Tsu-Mei, and a doctorate in applied biochemistry from Tsukuba University in Tsukuba, near Tokyo. He moved to the United States in 2000 when he joined the UC Davis faculty.
Recently, he was selected as a fellow of the Entomological Society of America, a prestigious honor that recognizes up to 10 members each year for their research and teaching contributions.
Leal's wife is an elementary school teacher, and the couple has three children. One is in college, the other two are 12 and 9. Leal claims to have no hobbies. "I work so hard, I have no time left," he said. "Actually, I have hobbies, but don't have time to do them."
Cycling is one of them, so he commutes by bicycle almost every day. It takes him about ten minutes. "Davis is a small, bike-friendly town, with lots of short cuts," he said.
Much as he loves bugs, Leal says he doesn't prefer them to people. Quite the opposite, in fact. "I like people more, which is why I work with mosquitoes--to protect people," he said.
-- Marlene Cimons, National Science Foundation
Throughout much of the last century, China's centrally planned, closed economy made the country an insignificant player in the global trading system. Today, having gone from a sleeping giant to one of the fastest growing economies, China is considered the "poster-child" for economic growth.
Many economists have called China's emergence a "positive economic shock," unleashing a consumer base and workforce of nearly 1.2 billion people into the global market.
China's transition into a market economy is driving changes in consumer preferences and demand for foods. Consumers are earning higher incomes and shifting consumption away from grains and legumes towards meat and other animal proteins. Pork, the primary meat consumed in China, accounts for nearly 70 percent of animal protein in Chinese diets. This makes China the world's largest pork consumer.
Because of its economic importance, the pork sector provides an excellent outlet to study the effects of economic development on consumer preferences and demand for goods.
For my National Science Foundation (NSF) East Asia and Pacific Summer Institute (EAPSI) program project in China in the summer, I conducted a Chinese consumer demand study that analyzed consumer preferences and willingness-to-pay for select food safety attributes in pork.
Food safety in China has become of paramount importance in the wake of numerous food-safety scandals. As part of my research experience, I worked closely with Chinese professors and graduate students to conduct an economic assessment of consumer preferences for food safety informational attributes.
We used a choice experiment where we simulated different pork-purchasing scenarios and consumers chose a product based on different attributes that we controlled. The informational attributes that we evaluated were: a product traceability system, a state-sponsored food safety assurance program, a third-party food safety assurance program and a product-specific information label.
After conducting this economic experiment numerous times in seven major Chinese cities, we analyzed the data using a series of econometric models designed specifically for choice experiment data.
As I traveled to various cities to gather the data for the study, I was given a unique opportunity to explore and learn about all aspects of Chinese society and local culture, from the grasslands of Inner Mongolia to the snow-covered peaks of the Himalayas in Tibet. It was in Tibet that I was fortunate to take the 24-hour train trip through the Tibetan plateau on the world's highest railway.
The EAPSI program also granted me the opportunity to attend two international conferences in China--a meeting of the Chinese Economist Society and a meeting of the International Association of Agricultural Economists--where I had the opportunity to present my ongoing research.
At these conferences, I was fortunate to meet world-renowned economists like Nobel Laureate Sir James Mirrlees, and through my interactions, I gained insight into new, cutting-edge methods in economic research. Specifically, I learned of new econometric methods that ultimately allow me to incorporate the dynamics of consumer preferences and risk perceptions into my analysis.
The results of my research quantified consumers' willingness-to-pay for food safety information in a transitioning economy. We found that Chinese consumers gained the most economic value from a state-sponsored food safety assurance program, and that the incorporation of a product-specific label and the implementation of a traceability system would add significant value to consumers.
-- David Ortega, Purdue University,
TOKYO (AP) — Almost everyone stood when the bride walked down the aisle in her white gown, but not the wedding conductor, because she was bolted to her chair.
The nuptials at this ceremony were led by "I-Fairy," a 4-foot tall seated robot with flashing eyes and plastic pigtails. Sunday's wedding was the first time a marriage had been led by a robot, according to manufacturer Kokoro Co.
"Please lift the bride's veil," the robot said in a tinny voice, waving its arms in the air as the newlyweds kissed in front of about 50 guests.
The wedding took place at a restaurant in Hibiya Park in central Tokyo, where the I-Fairy wore a wreath of flowers and directed a rooftop ceremony. Wires led out from beneath it to a black curtain a few feet away, where a man crouched and clicked commands into a computer.
Japan has one of the most advanced robotics industries in the world, with the government actively supporting the field for future growth. Industrial models in factories are now standard, but recently Japanese companies are making a push to inject robots into everyday life.
Honda makes a walking child-shaped robot, and other firms have developed them to entertain the elderly or play baseball. Kokoro, whose corporate goal is to "touch the hearts of the people," also makes giant dinosaur robots for exhibitions and lifelike android models that can smile and laugh. The company is a subsidiary of Sanrio Co., which owns the rights to Hello Kitty and other Japanese characters.
"This was a lot of fun. I think that Japanese have a strong sense that robots are our friends. Those in the robot industry mostly understand this, but people mainly want robots near them that serve some purpose," said bride Satoko Inoue, 36, who works at manufacturer Kokoro.
"It would be nice if the robot was a bit more clever, but she is very good at expressing herself," said new husband Tomohiro Shibata, 42, a professor of robotics at the Nara Institute of Science and Technology in central Japan.
The I-Fairy sells for about 6.3 million yen ($68,000) and three are in use in Singapore, the U.S. and Japan, according to company spokeswoman Kayako Kido. It has 18 degrees of motion in its arms, and mainly repeats preprogrammed movements and sounds.
Posts
