Canadian engineers suggest that research is needed into the risks associated with the growing field of nanotechnology manufacture so that appropriate protective equipment can be developed urgently.
Patricia Dolez of the Department of Mechanical Engineering, at the École de technologie supérieure, in Montréal and colleagues point out that skin is not an impervious membrane. This is the reason that protective clothing and gloves, in addition to respirators, are often an essential and common sight in the chemical industry. However, they wonder if standard protection against chemical risks is enough for workers who are handling nanomaterials.
According to the most recent estimates from the U.S. National Science Foundation, the nanotechnology market could reach as much as $1 trillion by 2011/2012. This, says Dolez, corresponds to about 2 million workers involved in nano-related activities. She adds that it has already been shown that nanoparticles may affect biological activity through oxidative stress at the cellular and molecular levels, although these effects are yet to be manifest as health problems among workers.
The anticipated hazards associated with this incredibly diverse range of substances falling under the general and broad tag of "nanomaterials" remain largely unknown. And, some scientists have suggested that we are vigilant to emerging health problems associated with nanomaterials. The U.S. government recently updated its National Nanotechnology Initiative strategic plan to highlight the need for an assessment of nanomaterials toxicity before production begins.
Dolez and colleagues suggest that as this area of manufacturing grows it would be prudent to develop adequate workplace protection sooner, rather than later. Indeed, those workers most likely to be exposed to nanomaterials will be working in cleaning, bagging and formulation activities as well as surface functionalisation of nanoparticles.
They explain that current regulations and standards testing for protective clothing and equipment are almost devoid of references to nanomaterials specifically. Moreover, although some researchers have concluded that certified respirators offer an appropriate level of protection against nanoparticles, there remain large uncertainties, for example due to the increased potential of leaks at face seal because of the very small size of nanoparticles, a few billionths of a meter.
Thursday, October 22, 2009
Wednesday, October 21, 2009
Computer Helps Deaf Children To Learn Sign Language
Three PhD candidates have spent the last few years at TU Delft simultaneously working on sign language. One of these is Jeroen Arendsen: “Very little is known about the perception of sign language. The aim of this research was to expand our knowledge of human observation of signing. For instance, it turns out that sign language users only need to see a small part of a hand movement to know it is a sign and what it means.”
Automatic Recognition:
The insights obtained into human perception can subsequently be used for developing the technology for automatic sign language recognition by cameras and computers. In the TU Delft study, this led to a remarkable application of automatic sign language recognition: an Electronic Learning Environment (ELo) for children who are deaf or hard of hearing.
Pictures:
In conjunction with the NSDSK (Dutch foundation for children who are deaf or hard of hearing), the TU Delft researchers developed a computer which can recognise sign language in real time and can therefore be used to teach children who are deaf and hard of hearing new signs more quickly.
When shown a picture, the children aged three to six were asked to make the correct sign. The computer then had to assess the sign. Arendsen: “And that is quite difficult, because a computer is more easily confused than people by irrelevant fidgeting.”
Comprehensible:
The task of fellow PhD candidate Jeroen Lichtenauer (EEMCS faculty) was to convert the signs into information which is comprehensible to a computer. As an Industrial Design Engineering student, Arendsen was more involved in the human aspects. Gineke Ten Holt was the third PhD candidate, who worked as a bridge between the two disciplines.
Sign Language Vocabulary:
Further research showed that the Electronic Learning Environment really does work. The sign language vocabulary of those children who had practised with it increased compared to that of a control group. This only applied to the slightly older children however.
Automatic Recognition:
The insights obtained into human perception can subsequently be used for developing the technology for automatic sign language recognition by cameras and computers. In the TU Delft study, this led to a remarkable application of automatic sign language recognition: an Electronic Learning Environment (ELo) for children who are deaf or hard of hearing.
Pictures:
In conjunction with the NSDSK (Dutch foundation for children who are deaf or hard of hearing), the TU Delft researchers developed a computer which can recognise sign language in real time and can therefore be used to teach children who are deaf and hard of hearing new signs more quickly.
When shown a picture, the children aged three to six were asked to make the correct sign. The computer then had to assess the sign. Arendsen: “And that is quite difficult, because a computer is more easily confused than people by irrelevant fidgeting.”
Comprehensible:
The task of fellow PhD candidate Jeroen Lichtenauer (EEMCS faculty) was to convert the signs into information which is comprehensible to a computer. As an Industrial Design Engineering student, Arendsen was more involved in the human aspects. Gineke Ten Holt was the third PhD candidate, who worked as a bridge between the two disciplines.
Sign Language Vocabulary:
Further research showed that the Electronic Learning Environment really does work. The sign language vocabulary of those children who had practised with it increased compared to that of a control group. This only applied to the slightly older children however.
Tuesday, October 20, 2009
New Technology Detects Chemical Weapons In Seconds
Scientists at Queen's University Belfast are developing new sensors to detect chemical agents and illegal drugs which will help in the fight against the threat of terrorist attacks.
The devices will use special gel pads to 'swipe' an individual or crime scene to gather a sample which is then analysed by a scanning instrument that can detect the presence of chemicals within seconds. This will allow better, faster decisions to be made in response to terrorist threats.
The scanning instrument will use Raman Spectroscopy which involves shining a laser beam onto the suspected sample and measuring the energy of light that scatters from it to determine what chemical compound is present. It is so sophisticated it can measure particles of a miniscule scale making detection faster and more accurate.
Normally this type of spectroscopy is not sensitive enough to detect low concentrations of chemicals, so here the sample is mixed with nanoscale silver particles which amplify the signals of compounds allowing even the smallest trace to be detected.
It is hoped the new sensors will also be the basis for developing 'breathalyzer' instruments that could be of particular use for roadside drugs testing in much the same way as the police take breathalyzer samples to detect alcohol.
At present, police officers are only able to use a Field Impairment Test to determine if a person is driving under the influence of drugs. The accuracy of this method has been questioned because of concerns that it is easy to cheat.
To ensure the technology is relevant, senior staff members from FSNI (Forensic Science Northern Ireland) will give significant input into the operational aspects of the technology and give feedback as to how it might be used in practice by the wider user community.
Stan Brown, Chief Executive of FSNI said:
"We consider the work being carried out by researchers at Queen's University extremely important and potentially very useful in driving forward the effectiveness, efficiency and speed of forensic science practice. The combination of leading edge research and hands-on experience of FSNI's practitioners has already proven very fruitful and is likely to lead to significant developments in forensic methodologies across a range of specialisms."
In the future this technology could have a number of important applications and according to Dr Bell: "There are numerous areas, from medical diagnostics to environmental monitoring, where the ability to use simple field tests to detect traces of important indicator compounds would be invaluable."
The devices will use special gel pads to 'swipe' an individual or crime scene to gather a sample which is then analysed by a scanning instrument that can detect the presence of chemicals within seconds. This will allow better, faster decisions to be made in response to terrorist threats.
The scanning instrument will use Raman Spectroscopy which involves shining a laser beam onto the suspected sample and measuring the energy of light that scatters from it to determine what chemical compound is present. It is so sophisticated it can measure particles of a miniscule scale making detection faster and more accurate.
Normally this type of spectroscopy is not sensitive enough to detect low concentrations of chemicals, so here the sample is mixed with nanoscale silver particles which amplify the signals of compounds allowing even the smallest trace to be detected.
It is hoped the new sensors will also be the basis for developing 'breathalyzer' instruments that could be of particular use for roadside drugs testing in much the same way as the police take breathalyzer samples to detect alcohol.
At present, police officers are only able to use a Field Impairment Test to determine if a person is driving under the influence of drugs. The accuracy of this method has been questioned because of concerns that it is easy to cheat.
To ensure the technology is relevant, senior staff members from FSNI (Forensic Science Northern Ireland) will give significant input into the operational aspects of the technology and give feedback as to how it might be used in practice by the wider user community.
Stan Brown, Chief Executive of FSNI said:
"We consider the work being carried out by researchers at Queen's University extremely important and potentially very useful in driving forward the effectiveness, efficiency and speed of forensic science practice. The combination of leading edge research and hands-on experience of FSNI's practitioners has already proven very fruitful and is likely to lead to significant developments in forensic methodologies across a range of specialisms."
In the future this technology could have a number of important applications and according to Dr Bell: "There are numerous areas, from medical diagnostics to environmental monitoring, where the ability to use simple field tests to detect traces of important indicator compounds would be invaluable."
Video Camera That Records At The Speed Of Thought
European Researchers who created an ultra-fast, extremely high-resolution video camera have enabled dozens of medical applications, including one scenario that can record ‘thought’ processes travelling along neurons.
The Megaframe project scored a staggering number of breakthroughs to create the world’s first 1024 pixel, photon-resolution, million-frame-per-second CMOS camera.
Their work has pushed the boundaries of CMOS (a type of semiconductor) miniaturisation and sophistication. But it is in the application of their technology that the most stunning impacts of the Megaframe project will be seen, particularly in medical applications.
That is because the camera can detect a single photon at a million times a second, and so it can record molecular processes in unprecedented detail. “We need this sort of detail because biomedical scientists are studying processes at the intra-cellular and molecular levels,” underlines Edoardo Charbon, coordinator of the EU-funded Megaframe project.
Scientists have developed extremely ingenious ways to infer or deduce what is happening at the molecular level, and Megaframe could make that process even more detailed. Essentially, scientists use a variety of emissive materials to see what is happening in microscopic biomedical processes.
Take Fluorescence Lifetime Imaging Microscopy (FLIM). Here, a fluorescent material is introduced to the area of interest. Fluorescence has some interesting properties, for example a particular spectrum of emission and a rate of decay.
One particular fluorophore, Oregon Green Bapta (OGB-1), decays at a rate proportionate to the presence of calcium. Interestingly, calcium is an important indicator of neuron activity.
So it is possible, for example, to go inside neurons and look at their ion channels. These are the channels that allow neurons to communicate with other neurons. And you can basically see the amount of calcium that is present. You can probe optically how neurons communicate with other neurons just by looking at the concentrations of calcium in real time.
So scientists can use the OGB-1 to indicate the presence and concentration of calcium, and the whole process can be recorded in ultra-fine detail thanks to single-photon detectors, such as the ones present in the Megaframe camera. The camera is recording at the speed of thought.
“Biomedical scientists could in principle use this microscopic information about calcium to learn about macroscopic conditions like Parkinson’s, or Alzheimer’s or epilepsy,” Charbon stresses.
Megaframe could have a significant impact on any medical science that uses visible light emissive scanning technologies like FLIM. But it can even have an impact where visible light is not present.
Other Applications:
Other applications currently under exploration by Megaframe include intracellular DNA sequencing and proteomics, two huge areas for drug discovery, as well as basic scientific research for gene sequencing and protein-folding.
Other areas where Megaframe’s work could boost research results include cell membrane scanning, to discover what bacteria or other material are present, and this research could be extended to look at issues like water purity, and waterborne bacteria.
Exploring further Potential:
Another very promising technique is the combination of fluorescence imaging with MRI, or magnetic resonance imaging. “In MRI you need very strong magnetic fields in the cavity where you are performing the imaging, up to 10 Tesla, but conventional fluorescence technology won't work in these conditions,” says Charbon.
But Megaframe’s choice of photo detector – the Single-Photon Avalanche Diode (SPAD) – have been tested successfully in fields up to 9.4 Tesla, he reveals.
“Thus, it can be envisaged to have a system where fluorescence-enhanced imaging and functional MRI may be used simultaneously,” Charbon enthuses. “This is very useful in a number of biomedical applications, where one wants to monitor the correlation between the presence of certain molecules in organs, such as the brain, and their function.”
Again, pharmacology could benefit from this technique enormously, as well as epidemiological research.
“Our preliminary tests were conducted in an animal MRI, which in general has much higher fields than a human MRI. Human MRI tests will follow,” reveals Charbon, adding that the technique has been tested with other SPAD-based microsensors and has yielded good results.
“Even though we have not tested it with the Megaframe chip, it is a guaranteed success because the technology is in principle the same,” Charbon predicts.
The Megaframe project has just begun to explore the potential for their camera in biomedical applications, and the list just keeps on growing as their research continues. And that is just in the biomedical field. There are dozens of potential applications in fields as diverse as high-energy physics, entertainment and automotive diagnostics.
The Megaframe project scored a staggering number of breakthroughs to create the world’s first 1024 pixel, photon-resolution, million-frame-per-second CMOS camera.
Their work has pushed the boundaries of CMOS (a type of semiconductor) miniaturisation and sophistication. But it is in the application of their technology that the most stunning impacts of the Megaframe project will be seen, particularly in medical applications.
That is because the camera can detect a single photon at a million times a second, and so it can record molecular processes in unprecedented detail. “We need this sort of detail because biomedical scientists are studying processes at the intra-cellular and molecular levels,” underlines Edoardo Charbon, coordinator of the EU-funded Megaframe project.
Scientists have developed extremely ingenious ways to infer or deduce what is happening at the molecular level, and Megaframe could make that process even more detailed. Essentially, scientists use a variety of emissive materials to see what is happening in microscopic biomedical processes.
Take Fluorescence Lifetime Imaging Microscopy (FLIM). Here, a fluorescent material is introduced to the area of interest. Fluorescence has some interesting properties, for example a particular spectrum of emission and a rate of decay.
One particular fluorophore, Oregon Green Bapta (OGB-1), decays at a rate proportionate to the presence of calcium. Interestingly, calcium is an important indicator of neuron activity.
So it is possible, for example, to go inside neurons and look at their ion channels. These are the channels that allow neurons to communicate with other neurons. And you can basically see the amount of calcium that is present. You can probe optically how neurons communicate with other neurons just by looking at the concentrations of calcium in real time.
So scientists can use the OGB-1 to indicate the presence and concentration of calcium, and the whole process can be recorded in ultra-fine detail thanks to single-photon detectors, such as the ones present in the Megaframe camera. The camera is recording at the speed of thought.
“Biomedical scientists could in principle use this microscopic information about calcium to learn about macroscopic conditions like Parkinson’s, or Alzheimer’s or epilepsy,” Charbon stresses.
Megaframe could have a significant impact on any medical science that uses visible light emissive scanning technologies like FLIM. But it can even have an impact where visible light is not present.
Other Applications:
Other applications currently under exploration by Megaframe include intracellular DNA sequencing and proteomics, two huge areas for drug discovery, as well as basic scientific research for gene sequencing and protein-folding.
Other areas where Megaframe’s work could boost research results include cell membrane scanning, to discover what bacteria or other material are present, and this research could be extended to look at issues like water purity, and waterborne bacteria.
Exploring further Potential:
Another very promising technique is the combination of fluorescence imaging with MRI, or magnetic resonance imaging. “In MRI you need very strong magnetic fields in the cavity where you are performing the imaging, up to 10 Tesla, but conventional fluorescence technology won't work in these conditions,” says Charbon.
But Megaframe’s choice of photo detector – the Single-Photon Avalanche Diode (SPAD) – have been tested successfully in fields up to 9.4 Tesla, he reveals.
“Thus, it can be envisaged to have a system where fluorescence-enhanced imaging and functional MRI may be used simultaneously,” Charbon enthuses. “This is very useful in a number of biomedical applications, where one wants to monitor the correlation between the presence of certain molecules in organs, such as the brain, and their function.”
Again, pharmacology could benefit from this technique enormously, as well as epidemiological research.
“Our preliminary tests were conducted in an animal MRI, which in general has much higher fields than a human MRI. Human MRI tests will follow,” reveals Charbon, adding that the technique has been tested with other SPAD-based microsensors and has yielded good results.
“Even though we have not tested it with the Megaframe chip, it is a guaranteed success because the technology is in principle the same,” Charbon predicts.
The Megaframe project has just begun to explore the potential for their camera in biomedical applications, and the list just keeps on growing as their research continues. And that is just in the biomedical field. There are dozens of potential applications in fields as diverse as high-energy physics, entertainment and automotive diagnostics.
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