Spitting cobras track first, predict later

Public release date: 14-May-2010
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Contact: Kathryn Knight
kathryn@biologists.com
44-787-634-4333
The Company of Biologists

Spitting cobras track first, predict later
Most venomous snakes are legendary for their lethal bites, but not all. Some spit defensively. Bruce Young, from the University of Massachusetts Lowell, explains that some cobras defend themselves by spraying debilitating venom into the eyes of an aggressor. Getting the chance to work with spitting cobras in South Africa, Young took the opportunity to record the venom spray tracks aimed at his eyes. Protected by a sheet of Perspex, Young caught the trails of venom and two things struck him: how accurately the snakes aimed and that each track was unique. This puzzled Young. For a start the cobra's fangs are fixed and they can't change the size of the venom orifice, 'so basic fluid dynamics would lead you to think that the pattern of the fluid should be fixed,' explains Young. But Young had also noticed that the snakes 'wiggled' their heads just before letting fly. 'The question became how do we reconcile those two things,' says Young, who publishes his discovery that the snakes initially track their victim's movement and then switch to predicting where the victim is going to be 200ms in the future in the Journal of Experimental Biology (http://jeb.biologists.org) on 14 May 2010.

Young remembers that Guido Westhoff had also noticed the spitting cobra's 'head wiggle', so he and his research assistant, Melissa Boetig, travelled to Horst Bleckmann's lab in the University of Bonn, Germany, to find out how spitting cobras fine-tune their venom spray. The team had to find out how a target provokes a cobra to spit, and Young was the man for that job, 'I just put on the goggles and the cobras start spitting all over,' laughs Young.

Wearing a visor fitted with accelerometers to track his own head movements while Boetig and Westhoff filmed the cobra's movements at 500 frames/s, Young stood in front of the animals and taunted them by weaving his head about. Over a period of 6 weeks, the team filmed over 100 spits before trying to discover why Young was so successful at provoking the snakes.

Analysing Young's movements, only one thing stood out; 200 ms before the snake spat, Young suddenly jerked his head. The team realised that Young's head jerk was the spitting trigger. They reasoned that the snake must be tracking Young's movements right up to the instant that he jerked his head and that it took a further 200 ms for the snake to react and fire off the venom.

But Young was still moving after triggering the snake into spitting and the snake can't steer the stream of venom, so how was the cobra able to successfully hit Young's eyes if it was aiming at a point where the target had been 200 ms previously? Realigning the data to the instant when Young jerked his head, the team compared all of the snakes' head movements and noticed that the cobras were all moving in a similar way. They accelerated their heads in the same direction that Young's eyes were moving. 'Not only does it speed up but it predicts where I am going to be and then it patterns its venom in that area,' explains Young.

So spitting cobras defend themselves by initially tracking an aggressor's movements. However, at the instant that an attacker triggers the cobra into spitting, the reptile switches to predicting where the attacker's eyes will be 200 ms in the future and aims there to be sure that it hits its target.


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IF REPORTING ON THIS STORY, PLEASE MENTION THE JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO: http://jeb.biologists.org

REFERENCE: Westhoff, G., Boetig, M., Bleckmann, H. and Young, B. A. (2010). Target tracking during venom 'spitting' by cobras. J. Exp. Biol. 213, 1797-1802.

This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required, and if reporting online a link to jeb.biologists.com is also required. The story posted here is COPYRIGHTED. Therefore advance permission is required before any and every reproduction of each article in full. PLEASE CONTACT permissions@biologists.com

THIS ARTICLE APPEARS IN THE JOURNAL OF EXPERIMENTAL BIOLOGY ON: 14 May 2010. EMBARGOED UNTIL FRIDAY, 14 May 2010, 00.15 HRS EDT (05:15 HRS BST)





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Nouns and verbs are learned in different parts of the brain. Click here for more information.

Public release date: 25-Feb-2010


Contact: SINC
info@plataformasinc.es
34-914-251-820
FECYT - Spanish Foundation for Science and Technology
Nouns and verbs are learned in different parts of the brain








IMAGE: Nouns and verbs are learned in different parts of the brain.
Click here for more information.

Two Spanish psychologists and a German neurologist have recently shown that the brain that activates when a person learns a new noun is different from the part used when a verb is learnt. The scientists observed this using brain images taken using functional magnetic resonance, according to an article they have published this month in the journal Neuroimage.

"Learning nouns activates the left fusiform gyrus, while learning verbs switches on other regions (the left inferior frontal gyrus and part of the left posterior medial temporal gyrus)", Antoni Rodríguez-Fornells, co-author of the study and an ICREA researcher at the Cognition and Brain Plasticity Unit of the University of Barcelona, tells SINC.

The Catalan researcher, along with psychologist Anna Mestres-Missé, who is currently working at the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig, and neurologist Thomas F. Münte from the Otto-von-Guericke University in Magdeburg, in Germany, have just published the results of their study confirming the neural differences in the map of the brain when a person learns new nouns and verbs in the journal Neuroimage.

The team knew that many patients with brain damage exhibit dissociation in processing these kinds of words, and that children learn nouns before verbs. Adults also perform better and react faster to nouns during cognitive tests.

Based on these ideas, the researchers devised an experiment to confirm whether these differences could be seen in the brain. To do this, they set 21 people a test to learn new nouns and verbs, and recorded their neural reactions using functional magnetic resonance imaging. This technique makes it possible to observe how regions of the brain activate while a person is carrying out a specific task.

The test consisted of working out the meaning of a new term based on the context provided in two sentences. For example, in the phrase "The girl got a jat for Christmas" and "The best man was so nervous he forgot the jat", the noun jat means "ring". Similarly, with "The student is nising noodles for breakfast" and "The man nised a delicious meal for her" the hidden verb is "cook".

"This task simulates, at an experimental level, how we acquire part of our vocabulary over the course of our lives, by discovering the meaning of new words in written contexts", explains Rodríguez-Fornells. "This kind of vocabulary acquisition based on verbal contexts is one of the most important mechanisms for learning new words during childhood and later as adults, because we are constantly learning new terms".

The participants had to learn 80 new nouns and 80 new verbs. By doing this, the brain imaging showed that new nouns primarily activate the left fusiform gyrus (the underside of the temporal lobe associated with visual and object processing), while the new verbs activated part of the left posterior medial temporal gyrus (associated with semantic and conceptual aspects) and the left inferior frontal gyrus (involved in processing grammar).

In addition, there was a positive correlation between activation of certain parts of the brain (the bilateral hippocampus and the bilateral putamen) and the efficiency of learning new nouns, but not new verbs.

"These results suggest that the same regions previously associated with the representation of the meaning of nouns and verbs are also associated with establishing correspondences between these meanings and new words, a process that is necessary for learning a second language", says Rodríguez-Fornells.

The researcher explains that the study cannot be used in practice for learning languages, "but it does touch on one of the most important aspects, which is the degree to which we use different information in verbal contexts, as well as possibly different neural networks, in learning different kinds of words with different grammatical functions".

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References:

Mestres-Missé, A., Rodriguez-Fornells, A., Münte, T.F. "Neural differences in the mapping of verb and noun concepts onto novel words". Neuroimage 49 (3): 2826�, 2010.

Fission chip fat fit for the road

THE FOLLWING NEWS IS REPRODUCED FROM WORLD NUCLEAR NEWS




Fission chip fat fit for the road
13 November 2009

http://www.world-nuclear-news.org/newsarticle.aspx?id=26526&jmid=18578&j=241039838&utm_source=JangoMail&utm_medium=Email&utm_campaign=WNN+Daily+13+November+2009+(241039838)&utm_content=ksparth%40yahoo.co.uk

[The Cumberland News, 13 November] Sellafield could be part of a new fuel cycle when used cooking oil from its six staff canteens is converted into biodiesel by a local farmer. James Stanley, whose land lies close to the Sellafield complex in Cumbria, is in talks over waste oil amounting to some 10,000 litres per month. To compliment his forthcoming biodiesel facility Stanley is also planning to build an anerobic digestor - fuelled by pigswill and silage - to warm the cooking oil with renewable heat before processing. The digester will cost £1.1 million ($1.8 million) and could be operating in nine months, subject to local permission. Stanley hopes to sell the nuclear biodiesel to Cumbria County Council.

Nuclear plant saved from swarm

Nuclear plant saved from swarm
22 August 2008

Nuclear sites are often havens for wildlife, but Britain's Sellafield proved too popular recently when a swarm of 40,000 bees descended on its Waste Encapsulation Plant. The main entrance near where the bees had gathered was immediately closed, and pest control specialists were summoned to neutralise the insect threat. However, the tiny creatures were saved from doom by the quick thinking of Tony Calvin, manufacturing manager at the neighbouring Magnox Encapsulation Plant. An amateur bee-keeper for ten years, Calvin raced home to fetch his specialised equipment before tempting the swarm to a new hive and moving them to a more becoming environment.

Novel fungus helps beetles to digest hard wood

Public release date: 18-Aug-2008
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Contact: Amitabh Avasthi
axa47@psu.edu
814-865-9481
Penn State
Novel fungus helps beetles to digest hard wood
The larva of Asian longhorned beetle feeds and develops exclusively on the the inner-wood of deciduous trees. A fungus within its gut alters lignin and makes it easier to break...
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University Park, Pa. -- A little known fungus tucked away in the gut of Asian longhorned beetles helps the insect munch through the hardest of woods according to a team of entomologists and biochemists. Researchers say the discovery could lead to innovative methods of controlling the invasive pest, and potentially offer more efficient ways of breaking down plant biomass for generating biofuels.

Microbes in the gut of insects are known to break down cellulose, but little is known about how, or whether, insects degrade lignin. This natural polymer helps plants stay upright and protects them from most forms of microbial attack.

"Lignin is nature's plastic and any organism that wants to get to the sugars in a plant has to be able to get past this protective barrier," said Ming Tien, study co-author and Penn State professor of biochemistry and molecular biology. "We suspect that the fungus produces enzymes that help the beetles degrade lignin."

Before this report, it was thought that insects are unable to extensively break down lignin, and that they get around the problem either by feasting on wood that has already degraded, or by living close to fungi that can degrade the wood for them.

But this theory fails to explain the ability of insects to feed and grow within healthy living trees.

"How these insects are able to circumvent this plastic wall [lignin] and get at the goodies, the sugars, behind it has remained a mystery," said Tien, who was recruited by Kelli Hoover, co-author and Penn State associate professor of entomology, and Scott Geib, lead author and Penn State doctoral student in entomology, to tease out an explanation.

The Asian longhorned beetle is one such insect that attacks healthy trees and bores through the hard wood to get at the succulent energy-rich matter inside. In the process, this invasive pest from China grows nearly 300-fold from being about the size of a grain of rice to a few inches in length.

Hoover and her colleagues speculated that the beetle could be harboring a community of microbes in the gut, which helps in breaking down lignin.

The researchers compared the chemical structure of non-degraded wood before and after it had passed through the gut of two wood-eating insects. To measure the degree of change in the lignin, they first fed pin oak wood to Asian longhorned beetles. Next they fed ponderosa pine wood to the Pacific dampwood termite, an insect that typically eats only dead wood.

Chemical analyses of feces from the two bugs indicated that they are able to alter the chemical structure of lignin by selectively adding or removing certain groups of molecules from the polymer.

Such alterations, said Geib, make it easier for the insect to break down wood.

"This fungus has genes that then make enzymes," explained Hoover, whose team's findings appear today (Aug. 18) in the Proceedings of the National Academy of Sciences. "We have been able to detect messages from the [fungal] DNA, which get translated into enzymes."

While the researchers have identified the fungus residing in the gut of the Asian longhorned beetle, they have yet to find one in the gut of the termite.

"The types of chemical changes we see in the beetle are similar to those seen in the white-rot fungus," said Geib. "Changes that we see in the termite are similar to those in the brown-rot fungus. The chemical changes to the lignin are similar."

However, Geib cautions that while the gut-borne fungus is certainly a key player in degrading wood, it may just be part of a bigger picture.

"It is likely that there is an interaction among enzymes produced by the fungus, hundreds of bacteria within the insect gut, and the insect itself," explained Geib. "It is a consortium that is doing the job."

If researchers manage to identify some of these key microbes, he says it might be possible to selectively target just those bacteria to impair the growth of Asian longhorned beetles, which have the potential to severely damage the lumber and maple syrup industry.

Both Geib and Hoover, who study Asian longhorned beetles, believe they may have stumbled upon a novel evolutionary adaptation in the insect world.

"This type of fungus [in the Asian longhorned beetle] is known to cause disease in plants," said Hoover, whose work is funded by the Alphawood Foundation and the Penn State College of Agricultural Sciences. "But this particular strain appears to be unique. It looks like these insects somehow acquired the fungus to live in their gut and help them break down wood."

She also points out that these fungi are more efficient than their free-ranging counterparts. While those fungi take months, even years, to break down wood, the gut-borne fungi seem to do it much faster.

Researchers say the speedy process could potentially be harnessed to produce biofuel.

"Getting rid of the lignin barrier and making the cellulose more accessible is the most expensive and environmentally unfriendly part of making ethanol from biomass," said Geib. The team's discovery, he added, could lead to the potential development of cheaper and more efficient enzymes for converting wood into ethanol.

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Other researchers on the paper include Timothy R. Filley, associate professor, department of earth and atmospheric sciences, Purdue University; Patrick G. Hatcher, the Batten endowed chair in physical sciences and professor of chemistry and biochemistry, and Rachel L. Sleighter, doctoral candidate, both at Old Dominion University; John E. Carlson, professor of molecular genetics, director of Schatz Center for Tree Molecular Genetics, School of Forestry; and Maria del Mar Jimenez-Gasco, assistant professor of plant pathology, both at Penn State.

Copper theft forces patients to skip cancer treatment

NORTH COUNTY TIMES

VISTA: Copper theft attempt halts cancer treatments
Without it, outpatient radiation machines couldn't be cooled

By COLLEEN MENSCHING - Staff Writer | Wednesday, July 30, 2008 8:10 PM PDT ∞


VISTA ---- As many as 65 cancer patients went without radiation therapy Wednesday after a would-be thief ripped out the copper plumbing that cooled the radiation machines at the private, outpatient clinic where they are being treated, police said.

"I have no word for these people," said patient Yulia Alvarez of Oceanside, who takes the bus to Oncology Therapies of Vista each day. "They don't understand how many lives depend on that machine."

The clinic's pipes, recovered at the scene, would have fetched between $300 to $400 at a recycling center, officials said.

Beth Bourbeau, office manager at the Sycamore Avenue clinic, said Wednesday that when she arrived at work, she discovered there was no running water. When she tried unsuccessfully to turn the water on at an outdoor valve, she saw tools and gloves left behind by whomever had yanked out the building's copper plumbing.

With the pipes dismantled, the clinic's large chilling unit was unable to provide the water needed to run its two radiation machines, she said.

Between 60 and 65 people were scheduled to receive radiation therapy at the clinic Wednesday, but none did, Bourbeau said.

Alvarez, in the middle of a six-week course of daily radiation, said she was nervous about missing her Wednesday dose. Bourbeau said missing one treatment was unlikely to have a negative effect on patients.

Plumbers who responded vowed to work through the night to get the operation up and running by Thursday, she said.

The attempted theft reflects a nationwide trend of copper thefts that began in 2005 when the value of the metal doubled in many markets. Thieves have targeted power lines, communications lines and construction sites.

Sgt. Art Wager of the Vista Sheriff's Station called the Sycamore Avenue theft a classic copper crime.

"I don't think this place was targeted simply because it was a cancer clinic," he said. "I think it was targeted because it was a commercial complex that was deserted in the middle of the night."

Bourbeau said she thinks the thief became spooked by something or someone and fled without the copper.

Bourbeau said that repairing the damage to the operation could cost several thousand dollars.

In addition, the clinic lost revenue it had expected to earn Wednesday, she said.

Wager said the Vista detective who recently led an undercover task force on metal theft was headed to the Sycamore Avenue scene Wednesday.

"Somebody knows who did this and they need to call us," he said.

Anyone with information about the theft is asked to call the Vista Sheriff's Station at (760) 940-4341.

Contact staff writer Colleen Mensching at (760) 739-6675 or cmensching@nctimes.com.