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Prosecuting Cyber Bullies
For years, kids who were the victims of bullying and teasing at school or on the playground could find refuge at home. But in the age of new technology, bullying has become a 24-hour problem, with harassers able to taunt and tease their peers through e-mail, text messages and social networks.
Alarm on broadband security
TELSTRA has raised serious national security concerns about the Rudd Government's plans for the national broadband network, which it claims undermine the ability of agencies to protect and monitor Australia's telecommunications system.
Pentagonal Ice Discovered: Could Be Used To Modify Weather
Researchers, in collaboration with University College London and the Fritz-Haber Institut in Berlin, created the first moments of water condensing on matter – a process vital for the formation of clouds in the atmosphere – by analysing how the two interact on a flat copper surface. Ice has rarely been viewed at the nanoscale before and the team discovered a one-dimensional chain structure built from pentagon-shaped rings, rather than the more commonly seen hexagonal structures of ice formations like those seen in snowflakes.
This discovery could lead to scientists developing new materials for seeding clouds and causing rain. Cloud seeding is a form of weather modification, where the amount or type of precipitation that falls from clouds is altered by dispersing substances into the air which modify cloud particles. This process can increase amounts of rain and snow but can also be used to suppress hail and fog. The substances currently used to seed clouds are chosen to bind to hexagonal ice, but this work suggests that the process could work equally well with materials which bind to other structures.
Professor Andrew Hodgson, from the University’s Surface Science Research Centre, said: “Water is a ubiquitous material that is central to many biological and chemical reactions, but its influence is often indirect and difficult to understand. Water usually takes on hexagonal arrangements, like those seen in snowflakes, yet this research has shown that the intricate, nanoscale structure of ice can actually be built from one-dimensional pentagons.
“Ice crystals form against flat, solid surfaces and watching the microscopic process take place on copper has provided detailed information on how ice forms at interfaces. The research will help to improve our understanding of how ice patterns form and how water is structured at metal interfaces.
“Many important chemical reactions take place at interfaces so understanding the structure of water in these environments will allow scientists to make better models of these processes. With a better understanding of how ice crystals form in the upper atmosphere, new and cheaper materials could now be developed that could be used across the globe to seed clouds and modify weather patterns."
Evolution-proof Insecticides May Stall Malaria Forever
Each year malaria -- spread through mosquito bites -- kills about a million people, but many of the chemicals used to kill the insects become ineffective. Repeated exposure to an insecticide breeds a new generation of mosquitoes that are resistant to that particular insecticide.
"Insecticides sprayed on house walls or bed nets are some of the most successful ways of controlling malaria," said Andrew Read, professor of biology and entomology, Penn State. "But they work by killing the insects or denying them the human blood they turn into eggs. This imposes an enormous selection in favor of insecticide-resistant mosquitoes."
Read and his colleagues Matthew Thomas, professor of entomology, Penn State, and Penelope Lynch, doctoral student, Open University, UK, argue that insecticides -- chemical or biological -- that kill only older mosquitoes are a more sustainable way to fight the deadly disease.
"If we killed only older mosquitoes we could control malaria and solve the problem of resistant mosquitoes," said Read. "This could be done by changing the way we use existing insecticides, even by simply diluting them," he added.
Aging mosquitoes are easier to kill with insecticides like DDT but new generation pesticides could do it too. Read and his colleagues are working with a biopesticide that kills older mosquitoes.
"It is one of the great ironies of malaria," explained Read, whose team's findings appear today (April 7) in PLoS Biology. "Most mosquitoes do not live long enough to transmit the disease. To stop malaria, we only need to kill the old mosquitoes."
Since most mosquitoes die before they become dangerous, late-acting insecticides will not have much impact on breeding, so there is much less pressure for the mosquitoes to evolve resistance, explained Read, who is also associated with the Penn State Center for Infectious Disease Dynamics. "This means that late-life insecticides will be useful for much, much longer -- maybe forever -- than conventional insecticides," he added. "Insects usually have to pay a price for resistance, and if only a few older mosquitoes gain the benefits, evolutionary economics can stop resistance from ever spreading."
"We are working on a fungal pesticide that kills mosquitoes late in life," said Thomas. "We could spray it onto walls or onto treated materials such as bed nets, from where the mosquito would get infected by the fungal spores." The fungi take 10 to 12 days to kill the insects. This achieves the benefit of killing the old, dangerous mosquitoes, while dramatically reducing the selection for the evolution of resistance, Thomas explained.
To study the impact of late-acting insecticides on mosquito populations, the researchers constructed a mathematical model of malaria transmission using factors such as the egg laying cycle of the mosquito and the development of parasites within the insect.
Once malaria parasites infect a mosquito, they need at least 10 to 14 days -- or two to six cycles of egg production -- to mature and migrate to the insect's salivary glands. From there they can pass into humans when a mosquito bites.
Analyses of the model using data on mosquito lifespan and malaria development from hotspots in Africa and Papua New Guinea reveal that insecticides killing only mosquitoes that have completed at least four cycles of egg production reduce the number of infectious bites by about 95 percent.
Critically, the researchers also found that resistance to late-acting insecticides spreads much more slowly among mosquitoes, compared to conventional insecticides, and that in many cases, it never spreads at all.
Read says the development of biological or chemical insecticides that are more effective against older, malaria-infected mosquitoes could save the millions dollars that will have to be spent to endlessly find new insecticides to replace ones that have become ineffective.
"Insecticides that kill indiscriminately impose maximal selection for mosquitoes that render those insecticides useless. Late-life acting insecticides would avoid that fate," Read added. "Done right, a one-off investment could create a single insecticide that would solve the problem of mosquito resistance forever."
'Molecular Ripcord' For Chemical Reactions
Researchers want to learn more about how humans use cognition to interact with their world. They believe iCub’s human-like body will help them to understand how this is done.
iCub has mechanical joints that enable it to move its head, arms, fingers, eyes and legs similarly to the way that humans do. Professor Murray Shanahan, of the Department of Computing, says this is important because cognition is very much tied up with the way we interact with the world.
“Nature developed cognition for us in order to make us better at interacting with the physical and social world,” he explains. “If we want to understand the nature of cognition better then we really need to understand it in the context of something that moves or interacts with objects. That is where iCub can help us.”
The team will test their theories about cognition by creating a computer simulation of a brain, which will replicate how neurons in real brains communicate through short bursts of electrical energy. In people, this process helps us to interact with the physical world. For instance, the electrical signals sent by neurons control muscles that enable people to lift a cup to the mouth to sip on a drink.
The team will link the computer simulation of a brain to iCub so that it can process information about its environment and send bursts of electrical energy to its motors to allow it to move its arms, head, eyes and fingers to carry out very simple tasks such as lifting a ball and moving it from one place to another.
If the researchers are successful, they will have made an important step in reproducing the way that humans use cognition to interact in their world. Professor Shanahan says:
“I’m really interested in the fundamental scientific questions about ourselves and about the nature of our own brains and how they allow us to do the kinds of things that we do each day. If we can test our theories about cognition by building and experimenting with robots, then we may just be one step closer to really beginning to understand what makes us tick.”
In the long term, they believe their research could help develop a new generation of intelligent factory robots that have much more versatility and do a wider variety of jobs.
Scientists are also interested in the part of cognition that allows humans to work with one another to carry out tasks.
They will develop computer programs that will allow iCub to interact with a human so that they can carry out a task together, such as building a Lego castle from scratch.
If they succeed, they will have demonstrated the cognitive processes that enable social interaction between humans, and have created a viable way for robots to interact with humans to help them to do things. Dr Yiannis Demiris, of the Department of Electrical and Electronic Engineering, adds:
“We are really interested in making robots more empathetic to our needs. Imagine owning a robot like iCub who could be intelligent enough to understand that you are struggling to lift a heavy box and it helps you to carry it or imagine getting it to help you put up a shelf or do the housework because it recognises that you are ill. The work that we are doing could one day make this a reality.”
Imperial received iCub in December 2008 as part of an ongoing project funded by the European Commission. Researchers expect to get their first results from their experiments in the next three to five years.