Entity

Time filter

Source Type

Nishi-Tokyo-shi, Japan

News Article
Site: http://www.biosciencetechnology.com/rss-feeds/all/rss.xml/all

Male zebra finches, small songbirds native to central Australia, learn their songs by copying what they hear from their fathers. These songs, often used as mating calls, develop early in life as juvenile birds experiment with mimicking the sounds they hear. MIT neuroscientists have now uncovered the brain activity that supports this learning process. Sequences of neural activity that encode the birds’ first song syllable are duplicated and altered slightly, allowing the birds to produce several variations on the original syllable. Eventually these syllables are strung together into the bird’s signature song, which remains constant for life. “The advantage here is that in order to learn new syllables, you don’t have to learn them from scratch. You can reuse what you’ve learned and modify it slightly. We think it’s an efficient way to learn various types of syllables,” said Tatsuo Okubo, a former MIT graduate student and lead author of the study, which appears in the Nov. 30 online edition of Nature. Okubo and his colleagues believe that this type of neural sequence duplication may also underlie other types of motor learning. For example, the sequence used to swing a tennis racket might be repurposed for a similar motion such as playing Ping-Pong. “This seems like a way that sequences might be learned and reused for anything that involves timing,” said Emily Mackevicius, an MIT graduate student who is also an author of the paper. The paper’s senior author is Michale Fee, a professor of brain and cognitive sciences at MIT and a member of the McGovern Institute for Brain Research. Previous studies from Fee’s lab have found that a part of the brain’s cortex known as the HVC is critical for song production. Typically, each song lasts for about one second and consists of multiple syllables. Fee’s lab has found that in adult birds, individual HVC neurons show a very brief burst of activity — about 10 milliseconds or less — at one moment during the song. Different sets of neurons are active at different times, and collectively the song is represented by this sequence of bursts. In the new Nature study, the researchers wanted to figure out how those neural patterns develop in newly hatched zebra finches. To do that, they recorded electrical activity in HVC neurons for up to three months after the birds hatched. When zebra finches begin to sing, about 30 days after hatching, they produce only nonsense syllables known as subsong, similar to the babble of human babies. At first, the duration of these syllables is highly variable, but after a week or so they turn into more consistent sounds called protosyllables, which last about 100 milliseconds. Each bird learns one protosyllable that forms a scaffold for subsequent syllables. The researchers found that within the HVC, neurons fire in a sequence of short bursts corresponding to the first protosyllable that each bird learns. Most of the neurons in the HVC participate in this original sequence, but as time goes by, some of these neurons are extracted from the original sequence and produce a new, very similar sequence. This chain of neural sequences can be repurposed to produce different syllables. “From that short sequence it splits into new sequences for the next new syllables,” Mackevicius said. “It starts with that short chain that has a lot of redundancy in it, and splits off some neurons for syllable A and some neurons for syllable B.” This splitting of neural sequences happens repeatedly until the birds can produce between three and seven different syllables, the researchers found. This entire process takes about two months, at which point each bird has settled on its final song. “This is a very natural way for motor patterns to evolve, by repeating something and then molding it, but until now nobody had any good data to understand how the brain actually does that,” said Ofer Tchernichovski, a professor of psychology at Hunter College who was not involved in the research. “What’s cool about this paper is they managed to follow how brain centers govern these transitions from simple repetitive patterns to more complex patterns." The researchers note that this process is similar to what is believed to drive the production of new genes and traits during evolution. “If you duplicate a gene, then you could have separate mutations in both copies of the gene and they could eventually do different functions,” Okubo said. “It’s similar with motor programs. You can duplicate the sequence and then independently modify the two daughter motor programs so that they can now each do slightly different things.” Mackevicius is now studying how input from sound-processing parts of the brain to the HVC contributes to the formation of these neural sequences.


News Article
Site: http://phys.org/biology-news/

MIT neuroscientists have now uncovered the brain activity that supports this learning process. Sequences of neural activity that encode the birds' first song syllable are duplicated and altered slightly, allowing the birds to produce several variations on the original syllable. Eventually these syllables are strung together into the bird's signature song, which remains constant for life. "The advantage here is that in order to learn new syllables, you don't have to learn them from scratch. You can reuse what you've learned and modify it slightly. We think it's an efficient way to learn various types of syllables," says Tatsuo Okubo, a former MIT graduate student and lead author of the study, which appears in the Nov. 30 online edition of Nature. Okubo and his colleagues believe that this type of neural sequence duplication may also underlie other types of motor learning. For example, the sequence used to swing a tennis racket might be repurposed for a similar motion such as playing Ping-Pong. "This seems like a way that sequences might be learned and reused for anything that involves timing," says Emily Mackevicius, an MIT graduate student who is also an author of the paper. The paper's senior author is Michale Fee, a professor of brain and cognitive sciences at MIT and a member of the McGovern Institute for Brain Research. Previous studies from Fee's lab have found that a part of the brain's cortex known as the HVC is critical for song production. Typically, each song lasts for about one second and consists of multiple syllables. Fee's lab has found that in adult birds, individual HVC neurons show a very brief burst of activity—about 10 milliseconds or less—at one moment during the song. Different sets of neurons are active at different times, and collectively the song is represented by this sequence of bursts. In the new Nature study, the researchers wanted to figure out how those neural patterns develop in newly hatched zebra finches. To do that, they recorded electrical activity in HVC neurons for up to three months after the birds hatched. When zebra finches begin to sing, about 30 days after hatching, they produce only nonsense syllables known as subsong, similar to the babble of human babies. At first, the duration of these syllables is highly variable, but after a week or so they turn into more consistent sounds called protosyllables, which last about 100 milliseconds. Each bird learns one protosyllable that forms a scaffold for subsequent syllables. The researchers found that within the HVC, neurons fire in a sequence of short bursts corresponding to the first protosyllable that each bird learns. Most of the neurons in the HVC participate in this original sequence, but as time goes by, some of these neurons are extracted from the original sequence and produce a new, very similar sequence. This chain of neural sequences can be repurposed to produce different syllables. "From that short sequence it splits into new sequences for the next new syllables," Mackevicius says. "It starts with that short chain that has a lot of redundancy in it, and splits off some neurons for syllable A and some neurons for syllable B." This splitting of neural sequences happens repeatedly until the birds can produce between three and seven different syllables, the researchers found. This entire process takes about two months, at which point each bird has settled on its final song. "This is a very natural way for motor patterns to evolve, by repeating something and then molding it, but until now nobody had any good data to understand how the brain actually does that," says Ofer Tchernichovski, a professor of psychology at Hunter College who was not involved in the research. "What's cool about this paper is they managed to follow how brain centers govern these transitions from simple repetitive patterns to more complex patterns." The researchers note that this process is similar to what is believed to drive the production of new genes and traits during evolution. "If you duplicate a gene, then you could have separate mutations in both copies of the gene and they could eventually do different functions," Okubo says. "It's similar with motor programs. You can duplicate the sequence and then independently modify the two daughter motor programs so that they can now each do slightly different things." Mackevicius is now studying how input from sound-processing parts of the brain to the HVC contributes to the formation of these neural sequences. More information: Growth and splitting of neural sequences in songbird vocal development, DOI: 10.1038/nature15741


News Article
Site: http://news.yahoo.com/science/

Felix Stiessen's and Valerie Roche's Apollo 11 Saturn V model will be reviewed by Lego for possible production. More A fan-designed scale model of NASA's historic Saturn V rocket has landed on Lego's launch pad and is now waiting an official "go/no-go" call as to whether it will lift off as a commercial set. The 3-foot-tall (1 m) version of the iconic Apollo 11 booster climbed to its qualifying 10,000th vote on Friday (Nov. 20) on the Lego Ideas website. The rocket, designed by Felix Stiessen and Valerie Roche, will now be considered by the Danish toymaker for possible production when it convenes its next review in January. "The Eagle has landed!" exclaimed Stiessen, in an update posted on Lego Ideas. "After more than a year our rocket finally completed its mission." [Lego Bricks and Spaceflight: A Photo Gallery] Stiessen, who built his first Lego Saturn V when he was just seven years old (a creation he described as "a 1 meter high pillar out of colorful bricks"), collaborated with Roche to design the latest version for Lego Ideas, which is made out of more than 2,300 pieces, including its custom stand. The model features stages that can be separated, detailed rocket engines and internal fuel tanks, and both the Apollo command and lunar modules that astronauts used to fly to the moon's surface and return safely to the Earth. "Although bigger projects seem to have less chances to pass [Lego's] review we are optimistic and hope to be the creators of the first big Lego Ideas set," the pair wrote. NASA launched 13 Saturn V boosters between 1967 and 1973, including nine that flew crews to the moon and one that deployed the United States' first space station, Skylab. The towering rocket stood 363 feet tall (110 m). It remains today the tallest, heaviest and most powerful rocket ever launched. Apollo 11's Saturn V, on which Stiessen and Roche based their model, lifted off on July 16, 1969 with astronauts Neil Armstrong, Buzz Aldrin and Michael Collins on board. The two designers first proposed their 1:110 scale Saturn V in commemoration of the 45th anniversary of the mission in 2014, and had recruited a third of the required votes by the next year. [Watch: Lego's New Spaceport Set Is Full of Awesome] To celebrate reaching 10,000 votes, Stiessen and Roche have released the building instructions for a "nano" version of the Saturn V, which stands just 10 inches (26 cm) tall. Designed using just 336 toy bricks (all available today from Lego), the small Saturn also features the rocket's crawler transporter, mobile platform and launch tower, too. "It's just a thank you to all supporters," explained Stiessen and Roche in an introduction to the instructions. "Take it as an early present and feel free to build your own version!" The Saturn V is the fifth space exploration-themed project to receive a review on Lego Ideas since the website was founded in 2008. Fan-created models of the Hubble Space Telescope and the International Space Station were turned down, but Lego sold kits based on Daisuke Okubo's toy version of Japan's Hayabusa asteroid sampling probe and Stephen Pakbaz's replica of NASA's Curiosity Mars Rover in 2012 and 2014, respectively. Presently, there are three other space-themed sets in the top 100 projects on Lego Ideas. A model of the Apollo 11 spacecraft has 2,700 supporters, a miniature of the Lunar Roving Vehicle has more than 1,600 votes, and an Apollo 17 playset created by Roche, Stiessen and Gabriel Russo, who designed the rejected Hubble telescope, has just over 1,420 backers. Lego previously sold one model of the Saturn V, although it was smaller and less detailed than the one proposed by Stiessen and Roche. In 2003, as part of a series of kits co-branded with the Discovery Channel, Lego released the "Saturn V Moon Mission," a 178-brick set that included the rocket, a lunar lander, Apollo command module and moon rover. Follow collectSPACE.com on Facebook and on Twitter at @collectSPACE. Copyright 2015 collectSPACE.com. All rights reserved. Copyright 2015 SPACE.com, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


Umezu S.,Okubo | Tanabe N.,Kitakaname | Hashimoto H.,Kitakaname
Key Engineering Materials | Year: 2015

Research on Micro air vehicle (MAV) has been carried out by many researchers to gather information in environmental monitoring, security and so on. When the earthquake, fire, smoke take place, it is difficult for human beings to investigate the detail because of dangerous condition. However, MAV has possibility to investigate the detail because MAV can fly freely around. Recently, dragonfly is highly focused by many researchers because dragonfly has high flight performances those are high efficiency flight, unintended acceleration, rapid turn and hovering. In general, these characteristics have root that wing is corrugation shape. We focus on microstructures on wing and its aerodynamic characteristics because there are many unique microstructures. We focused on micro spikes on dragonfly wing. Over three thousands of spikes exist on two sides of wing. The length and shape of spikes are 10 to 100 micron meters and oblique circular cone. It is important to clear the aerodynamic effect of the oblique circular cone. Artificial wing was fabricated by following processes. We fabricated micro spikes utilizing electro polishing. Fabricated micro spikes were set on plate utilizing micro spot bonding. We investigated the flow around the artificial wing and found that the flow around wing was controlled by micro spikes on wing. In this paper, we focused on comb shape of leading edge of wing. Comb shape is fabricated utilizing micro-EDM. We investigate flow characteristics of comb shape. © (2015) Trans Tech Publications. Source


News Article | April 28, 2016
Site: http://www.biosciencetechnology.com/rss-feeds/all/rss.xml/all

Hawaii officials say they have reached a milestone in controlling the state's dengue fever outbreak now that 30 days have passed since the last known infected person was contagious. "As we celebrate this milestone today, I think it's critical that everyone understand this is not the end," said Virginia Pressler, director of the state Department of Health. Hawaii welcomes 200,000 visitors per day, and the state's residents travel to places where dengue fever and the Zika virus - spread by the same mosquitoes - are endemic, Pressler said in a news conference Wednesday. "This is just the beginning of a new phase where we need to be prepared every day for a new mosquito-borne disease outbreak," she said. Hawaii Tourism Authority CEO George Szigeti said the timing of the announcement before the state's peak tourism season was ideal. "We are open for business," Szigeti said. "Travelers can book Hawaii with confidence and without hesitation." But some health officials are concerned about having adequate resources to combat potential future outbreaks of dengue fever or the Zika virus because lawmakers are approving less money to rebuild the state's mosquito-fighting team than Gov. David Ige requested. The state's mosquito-control staff was cut during the economic downturn, from 56 employees in 2009 to 25 positions in 2016. Ige had requested money to hire 33 new people, but state budget negotiators last week approved enough for only 20 new hires. "The department's a little concerned about having enough resources to be able to respond to the continuing threats," said Janice Okubo, spokeswoman for the Department of Health. State and county crews are continuing mosquito surveillance and cleanups. They recently worked with a Big Island property owner to remove more than 1,000 tires, which can be breeding grounds for mosquitoes, said Darryl Oliveira, administrator of the Hawaii County Civil Defense Agency. "We're always vulnerable to these types of threats, and although we're seeing a decline in the number of cases ... by no means are we out of the clear," Oliveira said. Hawaii has been in a state of emergency to fight mosquito-borne illnesses since February. Ige said the dengue outbreak helped the state prepare for future health emergencies. There have been 263 confirmed dengue fever cases in Hawaii since September.

Discover hidden collaborations