ֱ̽ of Cambridge - Flexible electronics /taxonomy/subjects/flexible-electronics en ‘Wraparound’ implants represent new approach to treating spinal cord injuries /research/news/wraparound-implants-represent-new-approach-to-treating-spinal-cord-injuries <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/gettyimages-1607123293-dp.jpg?itok=H6YqWz_2" alt="Illustration of spinal cord" title="Illustration of spinal cord, Credit: SEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>A team of engineers, neuroscientists and surgeons from the ֱ̽ of Cambridge developed the devices and used them to record the nerve signals going back and forth between the brain and the spinal cord. Unlike current approaches, the Cambridge devices can record 360-degree information, giving a complete picture of spinal cord activity.</p> <p>Tests in live animal and human cadaver models showed the devices could also stimulate limb movement and bypass complete spinal cord injuries where communication between the brain and spinal cord had been completely interrupted.</p> <p>Most current approaches to treating spinal injuries involve both piercing the spinal cord with electrodes and placing implants in the brain, which are both high-risk surgeries. ֱ̽Cambridge-developed devices could lead to treatments for spinal injuries without the need for brain surgery, which would be far safer for patients.</p> <p>While such treatments are still at least several years away, the researchers say the devices could be useful in the near-term for monitoring spinal cord activity during surgery. Better understanding of the spinal cord, which is difficult to study, could lead to improved treatments for a range of conditions, including chronic pain, inflammation and hypertension. ֱ̽<a href="https://doi.org/10.1126/sciadv.adl1230">results</a> are reported in the journal <em>Science Advances</em>.</p> <p>“ ֱ̽spinal cord is like a highway, carrying information in the form of nerve impulses to and from the brain,” said Professor George Malliaras from the Department of Engineering, who co-led the research. “Damage to the spinal cord causes that traffic to be interrupted, resulting in profound disability, including irreversible loss of sensory and motor functions.”</p> <p> ֱ̽ability to monitor signals going to and from the spinal cord could dramatically aid in the development of treatments for spinal injuries, and could also be useful in the nearer term for better monitoring of the spinal cord during surgery.</p> <p>“Most technologies for monitoring or stimulating the spinal cord only interact with motor neurons along the back, or dorsal, part of the spinal cord,” said Dr Damiano Barone from the Department of Clinical Neurosciences, who co-led the research. “These approaches can only reach between 20 and 30 percent of the spine, so you’re getting an incomplete picture.”</p> <p>By taking their inspiration from microelectronics, the researchers developed a way to gain information from the whole spine, by wrapping very thin, high-resolution implants around the spinal cord’s circumference. This is the first time that safe 360-degree recording of the spinal cord has been possible – earlier approaches for 360-degree monitoring use electrodes that pierce the spine, which can cause spinal injury.</p> <p> ֱ̽Cambridge-developed biocompatible devices – just a few millionths of a metre thick – are made using advanced photolithography and thin film deposition techniques, and require minimal power to function.</p> <p> ֱ̽devices intercept the signals travelling on the axons, or nerve fibres, of the spinal cord, allowing the signals to be recorded. ֱ̽thinness of the devices means they can record the signals without causing any damage to the nerves, since they do not penetrate the spinal cord itself.</p> <p>“It was a difficult process, because we haven’t made spinal implants in this way before, and it wasn’t clear that we could safely and successfully place them around the spine,” said Malliaras. “But because of recent advances in both engineering and neurosurgery, the planets have aligned and we’ve made major progress in this important area.”</p> <p> ֱ̽devices were implanted using an adaptation to routine surgical procedure so they could be slid under the spinal cord without damaging it. In tests using rat models, the researchers successfully used the devices to stimulate limb movement. ֱ̽devices showed very low latency – that is, their reaction time was close to human reflexive movement. Further tests in human cadaver models showed that the devices can be successfully placed in humans.</p> <p> ֱ̽researchers say their approach could change how spinal injuries are treated in future. Current attempts to treat spinal injuries involve both brain and spinal implants, but the Cambridge researchers say the brain implants may not be necessary.</p> <p>“If someone has a spinal injury, their brain is fine, but it’s the connection that’s been interrupted,” said Barone. “As a surgeon, you want to go where the problem is, so adding brain surgery on top of spinal surgery just increases the risk to the patient. We can collect all the information we need from the spinal cord in a far less invasive way, so this would be a much safer approach for treating spinal injuries.”</p> <p>While a treatment for spinal injuries is still years away, in the nearer term, the devices could be useful for researchers and surgeons to learn more about this vital, but understudied, part of human anatomy in a non-invasive way. ֱ̽Cambridge researchers are currently planning to use the devices to monitor nerve activity in the spinal cord during surgery.</p> <p>“It’s been almost impossible to study the whole of the spinal cord directly in a human, because it’s so delicate and complex,” said Barone. “Monitoring during surgery will help us to understand the spinal cord better without damaging it, which in turn will help us develop better therapies for conditions like chronic pain, hypertension or inflammation. This approach shows enormous potential for helping patients.”</p> <p> ֱ̽research was supported in part by the Royal College of Surgeons, the Academy of Medical Sciences, Health Education England, the National Institute for Health Research, <a href="https://otr.medschl.cam.ac.uk/funding/confidence-concept/cic-previous-awards">MRC Confidence in Concept</a>, and the Engineering and Physical Sciences Research Council (EPSRC), part of UK Research and Innovation (UKRI).</p> <p> </p> <p><em><strong>Reference:</strong><br /> Ben J Woodington, Jiang Lei et al. ‘<a href="https://doi.org/10.1126/sciadv.adl1230">Flexible Circumferential Bioelectronics to Enable 360-degree Recording and Stimulation of the Spinal Cord</a>.’ Science Advances (2024). DOI: 10.1126/sciadv.adl1230</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>A tiny, flexible electronic device that wraps around the spinal cord could represent a new approach to the treatment of spinal injuries, which can cause profound disability and paralysis.</p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Because of recent advances in both engineering and neurosurgery, the planets have aligned and we’ve made major progress in this important area</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">George Malliaras</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">SEBASTIAN KAULITZKI/SCIENCE PHOTO LIBRARY</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Illustration of spinal cord</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="https://creativecommons.org/licenses/by-nc-sa/4.0/" rel="license"><img alt="Creative Commons License." src="/sites/www.cam.ac.uk/files/inner-images/cc-by-nc-sa-4-license.png" style="border-width: 0px; width: 88px; height: 31px;" /></a><br /> ֱ̽text in this work is licensed under a <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/">Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 08 May 2024 18:01:25 +0000 sc604 245871 at Washable, wearable battery-like devices could be woven directly into clothes /research/news/washable-wearable-battery-like-devices-could-be-woven-directly-into-clothes <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/crop_115.jpg?itok=9-rX6xbp" alt="" title="Schematic of the textile-based capacitor integrating GNP/polyesters as electrodes and h-BN/polyesters as dielectrics., Credit: Felice Torrisi" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>Wearable electronic components incorporated directly into fabrics have been developed by researchers at the ֱ̽ of Cambridge. ֱ̽devices could be used for flexible circuits, healthcare monitoring, energy conversion, and other applications.</p> <p> ֱ̽Cambridge researchers, working in collaboration with colleagues at Jiangnan ֱ̽ in China, have shown how graphene – a two-dimensional form of carbon – and other related materials can be directly incorporated into fabrics to produce charge storage elements such as capacitors, paving the way to textile-based power supplies which are washable, flexible and comfortable to wear.</p> <p> ֱ̽<a href="https://pubs.rsc.org/en/content/articlelanding/2019/nr/c9nr00463g#!divAbstract">research</a>, published in the journal <em>Nanoscale</em>, demonstrates that graphene inks can be used in textiles able to store electrical charge and release it when required. ֱ̽new textile electronic devices are based on low-cost, sustainable and scalable dyeing of polyester fabric. ֱ̽inks are produced by standard solution processing techniques.</p> <p>Building on previous work by the same team, the researchers designed inks which can be directly coated onto a polyester fabric in a simple dyeing process. ֱ̽versatility of the process allows various types of electronic components to be incorporated into the fabric.  </p> <p>Most other wearable electronics rely on rigid electronic components mounted on plastic or textiles. These offer limited compatibility with the skin in many circumstances, are damaged when washed and are uncomfortable to wear because they are not breathable.</p> <p>“Other techniques to incorporate electronic components directly into textiles are expensive to produce and usually require toxic solvents, which makes them unsuitable to be worn,” said Dr Felice Torrisi from the Cambridge Graphene Centre, and the paper’s corresponding author. “Our inks are cheap, safe and environmentally-friendly, and can be combined to create electronic circuits by simply overlaying different fabrics made of two-dimensional materials on the fabric.”</p> <p> ֱ̽researchers suspended individual graphene sheets in a low boiling point solvent, which is easily removed after deposition on the fabric, resulting in a thin and uniform conducting network made up of multiple graphene sheets. ֱ̽subsequent overlay of several graphene and hexagonal boron nitride (h-BN) fabrics creates an active region, which enables charge storage. This sort of ‘battery’ on fabric is bendable and can withstand washing cycles in a normal washing machine.</p> <p>“Textile dyeing has been around for centuries using simple pigments, but our result demonstrates for the first time that inks based on graphene and related materials can be used to produce textiles that could store and release energy,” said co-author Professor Chaoxia Wang from Jiangnan ֱ̽ in China. “Our process is scalable and there are no fundamental obstacles to the technological development of wearable electronic devices both in terms of their complexity and performance.”</p> <p> ֱ̽work done by the Cambridge researchers opens a number of commercial opportunities for ink based on two-dimensional materials, ranging from personal health and well-being technology, to wearable energy and data storage, military garments, wearable computing and fashion.</p> <p>“Turning textiles into functional energy storage elements can open up an entirely new set of applications, from body-energy harvesting and storage to the Internet of Things,” said Torrisi “In the future our clothes could incorporate these textile-based charge storage elements and power wearable textile devices.”</p> <p> ֱ̽research was supported by the Engineering and Physical Science Research Council, the Newton Trust, the National Natural Science Foundation of China and the Ministry of Science and Technology of China. ֱ̽technology is being commercialised by Cambridge Enterprise, the ֱ̽’s commercialisation arm.</p> <p><strong><em>Reference:</em></strong><br /> <em>Qiang, S et al. ‘<a href="https://pubs.rsc.org/en/content/articlelanding/2019/nr/c9nr00463g#!divAbstract">Wearable solid-state capacitors based on two-dimensional material all-textile heterostructures</a>.’ Nanoscale (2019). DOI: </em><em>10.1039/C9NR00463G</em></p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Washable, wearable ‘batteries’: based on cheap, safe and environmentally-friendly inks and woven directly into fabrics, have been developed by researchers at the ֱ̽ of Cambridge.</p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Turning textiles into functional energy storage elements can open up an entirely new set of applications</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Felice Torrisi</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Felice Torrisi</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Schematic of the textile-based capacitor integrating GNP/polyesters as electrodes and h-BN/polyesters as dielectrics.</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br /> ֱ̽text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified.  All rights reserved. We make our image and video content available in a number of ways – as here, on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 15 May 2019 23:00:36 +0000 sc604 205362 at Electronic device implanted in the brain could stop seizures /research/news/electronic-device-implanted-in-the-brain-could-stop-seizures <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/crop_88.jpg?itok=5uqeJU0t" alt="Green arrow points to the implant in the hippocampus of a mouse brain" title="Green arrow points to the implant in the hippocampus of a mouse brain, Credit: Christopher Proctor" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> ֱ̽researchers, from the ֱ̽ of Cambridge, the École Nationale Supérieure des Mines and INSERM in France, implanted the device into the brains of mice, and when the first signals of a seizure were detected, delivered a native brain chemical which stopped the seizure from progressing. ֱ̽<a href="https://doi.org/10.1126/sciadv.aau1291">results</a>, reported in the journal <em>Science Advances</em>, could also be applied to other conditions including brain tumours and Parkinson’s disease.</p>&#13; &#13; <p> ֱ̽work represents another advance in the development of soft, flexible electronics that interface well with human tissue. “These thin, organic films do minimal damage in the brain, and their electrical properties are well-suited for these types of applications,” said Professor George Malliaras, the Prince Philip Professor of Technology in Cambridge’s Department of Engineering, who led the research.</p>&#13; &#13; <p>While there are many different types of seizures, in most patients with epilepsy, neurons in the brain start firing and signal to neighbouring neurons to fire as well, in a snowball effect that can affect consciousness or motor control. Epilepsy is most commonly treated with anti-epileptic drugs, but these drugs often have serious side effects and they do not prevent seizures in three out of 10 patients.</p>&#13; &#13; <p>In the current work, the researchers used a neurotransmitter which acts as the ‘brake’ at the source of the seizure, essentially signalling to the neurons to stop firing and end the seizure. ֱ̽drug is delivered to the affected region of the brain by a neural probe incorporating a tiny ion pump and electrodes to monitor neural activity.</p>&#13; &#13; <p>When the neural signal of a seizure is detected by the electrodes, the ion pump is activated, creating an electric field that moves the drug across an ion exchange membrane and out of the device, a process known as electrophoresis. ֱ̽amount of drug can be controlled by tuning the strength of the electric field.</p>&#13; &#13; <p>“In addition to being able to control exactly when and how much drug is delivered, what is special about this approach is that the drugs come out of the device without any solvent,” said lead author Dr Christopher Proctor, a postdoctoral researcher in the Department of Engineering. “This prevents damage to the surrounding tissue and allows the drugs to interact with the cells immediately outside the device.”</p>&#13; &#13; <p> ֱ̽researchers found that seizures could be prevented with relatively small doses of drug representing less than 1% of the total amount of drug loaded into the device. This means the device should be able to operate for extended periods without needing to be refilled. They also found evidence that the delivered drug, which was in fact a neurotransmitter that is native to the body, was taken up by natural processes in the brain within minutes which, the researchers say, should help reduce side effects from the treatment.</p>&#13; &#13; <p>Although early results are promising, the potential treatment would not be available for humans for several years. ֱ̽researchers next plan to study the longer-term effects of the device in mice.</p>&#13; &#13; <p>Malliaras is establishing a new facility at Cambridge which will be able to prototype these specialised devices, which could be used for a range of conditions. Although the device was tested in an animal model of epilepsy, the same technology could potentially be used for other neurological conditions, including the treatment of brain tumours and Parkinson’s disease.</p>&#13; &#13; <p> ֱ̽research was funded by the European Union.</p>&#13; &#13; <p><strong><em>Reference: </em></strong><br /><em>Christopher M. Proctor et al. ‘<a href="https://doi.org/10.1126/sciadv.aau1291">Electrophoretic drug delivery for seizure control</a>.’ Science Advances (2018). DOI: 10.1126/sciadv.aau1291</em></p>&#13; &#13; <p> </p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Researchers have successfully demonstrated how an electronic device implanted directly into the brain can detect, stop and even prevent epileptic seizures. </p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">These thin, organic films do minimal damage in the brain, and their electrical properties are well-suited for these types of applications.</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">George Malliaras</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Christopher Proctor</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Green arrow points to the implant in the hippocampus of a mouse brain</div></div></div><div class="field field-name-field-panel-title field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Researcher profile: Dr Christopher Proctor</div></div></div><div class="field field-name-field-panel-body field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><img alt="" src="/sites/www.cam.ac.uk/files/inner-images/chris-crop.jpg" style="width: 590px; height: 288px;" /></p>&#13; &#13; <p><em>Dr Christopher Proctor is one of the first nine recipients of the <a href="https://www.postdocacademy.cam.ac.uk/professional-opportunities/fellowships/borysiewicz-interdisciplinary-fellowship">Borysiewicz Biomedical Sciences Fellowship</a> programme.</em></p>&#13; &#13; <p>My research sets out to develop medical devices to treat and diagnose various health problems that have been difficult to address with conventional approaches such as epilepsy, Parkinson’s disease and brain tumours. As an engineer with expertise in electronics and materials, I work closely with biologists and clinicians in all stages of device development from early stage designing to late-stage testing.</p>&#13; &#13; <p> ֱ̽most exciting day I’ve had in research so far was when a concept that I took from a drawing on paper to a real device that I could hold in my hand, prevented a seizure for the third time. I say the third time because I am forever a sceptic, so I was hesitant to believe our initial results until we repeated it a couple times. Having seen that it was a repeatable result was very exciting because that is when you know you may really be on to something special.</p>&#13; &#13; <p>I hope my research will ultimately lead to a better quality of life for people with health problems. I believe we are only scraping the surface of what is possible when we pair electronic devices with biology. It is difficult to project where early-stage research will go, but I suspect the way we address some of the most difficult to treat diseases may be radically different in the coming decades.</p>&#13; &#13; <p>Cambridge is a great place to research and develop medical devices because this type of work is truly a team effort that requires expertise in everything from engineering to chemistry to medicine up to government regulations, finance and marketing. There is an ecosystem in and around the ֱ̽ of Cambridge that can bring all these experts together and that is exactly what is needed to take an early stage technology all the way to the patients that we are trying to help.</p>&#13; </div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />&#13; ֱ̽text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>. Images, including our videos, are Copyright © ֱ̽ of Cambridge and licensors/contributors as identified.  All rights reserved. We make our image and video content available in a number of ways – as here, on our <a href="/">main website</a> under its <a href="/about-this-site/terms-and-conditions">Terms and conditions</a>, and on a <a href="/about-this-site/connect-with-us">range of channels including social media</a> that permit your use and sharing of our content under their respective Terms.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 29 Aug 2018 18:00:00 +0000 sc604 199722 at Fully integrated circuits printed directly onto fabric /research/news/fully-integrated-circuits-printed-directly-onto-fabric <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/news/crop_49.jpg?itok=TX86wTVy" alt="Sample circuit printed on fabric" title="Sample circuit printed on fabric, Credit: Felice Torrisi" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> ֱ̽researchers, from the ֱ̽ of Cambridge, working with colleagues in Italy and China, have demonstrated how graphene – a two-dimensional form of carbon – can be directly printed onto fabric to produce integrated electronic circuits which are comfortable to wear and can survive up to 20 cycles in a typical washing machine.</p>&#13; &#13; <p> ֱ̽new textile electronic devices are based on low-cost, sustainable and scalable inkjet printing of inks based on graphene and other two-dimensional materials, and are produced by standard processing techniques. ֱ̽<a href="https://www.nature.com/articles/s41467-017-01210-2">results</a> are published in the journal <em>Nature Communications</em>.</p>&#13; &#13; <p>Based on <a href="https://pubs.acs.org/doi/abs/10.1021/nn2044609">earlier work</a> on the formulation of graphene inks for printed electronics, the team designed low-boiling point inks, which were directly printed onto polyester fabric. Additionally, they found that modifying the roughness of the fabric improved the performance of the printed devices. ֱ̽versatility of this process allowed the researchers to design not only single transistors but all-printed integrated electronic circuits combining active and passive components.</p>&#13; &#13; <p>Most wearable electronic devices that are currently available rely on rigid electronic components mounted on plastic, rubber or textiles. These offer limited compatibility with the skin in many circumstances, are damaged when washed and are uncomfortable to wear because they are not breathable.</p>&#13; &#13; <p>“Other inks for printed electronics normally require toxic solvents and are not suitable to be worn, whereas our inks are both cheap, safe and environmentally-friendly, and can be combined to create electronic circuits by simply printing different two-dimensional materials on the fabric,” said Dr Felice Torrisi of the Cambridge Graphene Centre, the paper’s senior author.</p>&#13; &#13; <p>“Digital textile printing has been around for decades to print simple colourants on textiles, but our result demonstrates for the first time that such technology can also be used to print the entire electronic integrated circuits on textiles,” said co-author Professor Roman Sordan of Politecnico di Milano. “Although we demonstrated very simple integrated circuits, our process is scalable and there are no fundamental obstacles to the technological development of wearable electronic devices both in terms of their complexity and performance.“</p>&#13; &#13; <p>“ ֱ̽printed components are flexible, washable and require low power, essential requirements for applications in wearable electronics,” said PhD student Tian Carey, the paper’s first author.</p>&#13; &#13; <p> ֱ̽work opens up a number of commercial opportunities for two-dimensional material inks, ranging from personal health and well-being technology, to wearable energy harvesting and storage, military garments, wearable computing and fashion.</p>&#13; &#13; <p>“Turning textile fibres into functional electronic components can open to an entirely new set of applications from healthcare and wellbeing to the Internet of Things,” said Torrisi. “Thanks to nanotechnology, in the future our clothes could incorporate these textile-based electronics, such as displays or sensors and become interactive.”</p>&#13; &#13; <p> ֱ̽use of graphene and other related 2D material (GRM) inks to create electronic components and devices integrated into fabrics and innovative textiles is at the centre of new technical advances in the smart textiles industry. ֱ̽teams at the Cambridge Graphene Centre and Politecnico di Milano are also involved in the Graphene Flagship, an EC-funded, pan-European project dedicated to bringing graphene and GRM technologies to commercial applications.</p>&#13; &#13; <p> ֱ̽research was supported by grants from the Graphene Flagship, the European Research Council’s Synergy Grant, ֱ̽Engineering and Physical Science Research Council, ֱ̽Newton Trust, the International Research Fellowship of the National Natural Science Foundation of China and the Ministry of Science and Technology of China. ֱ̽technology is being commercialised by Cambridge Enterprise, the ֱ̽’s commercialisation arm.</p>&#13; &#13; <p><strong><em>Reference:</em></strong><br /><em>Tian Carey et al. ‘</em><a href="https://www.nature.com/articles/s41467-017-01210-2"><em>Fully inkjet-printed two-dimensional material field-effect heterojunctions for wearable and textile electronics</em></a><em>.’ Nature Communications (2017). DOI: 10.1038/s41467-017-01210-2</em></p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Researchers have successfully incorporated washable, stretchable and breathable electronic circuits into fabric, opening up new possibilities for smart textiles and wearable electronics. ֱ̽circuits were made with cheap, safe and environmentally friendly inks, and printed using conventional inkjet printing techniques. </p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Turning textile fibres into functional electronic components can open to an entirely new set of applications from healthcare and wellbeing to the Internet of Things.</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Felice Torrisi</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Felice Torrisi</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Sample circuit printed on fabric</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />&#13; ֱ̽text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/" rel="license">Creative Commons Attribution 4.0 International License</a>. For image use please see separate credits above.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 08 Nov 2017 00:01:00 +0000 sc604 193002 at Opinion: Why are flexible computer screens taking so long to develop? /research/discussion/opinion-why-are-flexible-computer-screens-taking-so-long-to-develop <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/research/discussion/160118flexiblescreen.jpg?itok=y8NOeI-u" alt="Circuits patterned on a plastic substrate" title="Circuits patterned on a plastic substrate, Credit: Stuart Higgins" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>It’s common to first see exciting new technologies in science fiction, but less so in stories about wizards and dragons. Yet one of the most interesting bits of kit on display at this year’s Consumer Electronics Show (CES) in Las Vegas was reminiscent of the magical <a href="https://harrypotter.fandom.com/wiki/Daily_Prophet">Daily Prophet</a> newspaper in the Harry Potter series.</p>&#13; &#13; <p>Thin, flexible screens such as the one <a href="http://www.bbc.co.uk/news/technology-35230043">showcased by LG</a> could allow the creation of newspapers that change daily, display video like a tablet computer, but that can still be rolled up and put in your pocket. These plastic electronic displays could also provide smartphones with shatterproof displays (good news for anyone who’s inadvertently tried drop-testing their phone onto the pavement) and lead to the next generation of flexible wearable technology.</p>&#13; &#13; <p>But LG’s announcement is <a href="https://www.theguardian.com/technology/blog/2013/jan/11/ces-2013-samsung-bendy-screen">not the first time</a> that flexible displays has been demonstrated at CES. We’ve seen similar technologies every year for some time now, and LG itself unveiled another prototype in a <a href="https://www.lgdisplay.com:443/eng/prcenter/newsView?articleMgtNo=4874">press release</a> 18 months ago. Yet only a handful of products have come to market that feature flexible displays, and those have the <a href="https://www.engadget.com/2014-09-03-samsung-galaxy-note-edge-hands-on.html">displays mounted</a> in a <a href="https://www.independent.co.uk/life-style/gadgets-and-tech/sony-promises-an-end-to-the-a4-notepad-with-flexible-digital-paper-9227913.html">rigid holder</a>, rather than free for the user to bend. So why is this technology taking so long to reach our homes?</p>&#13; &#13; <h2>How displays work</h2>&#13; &#13; <p> </p>&#13; &#13; <figure class="align-left zoomable"><a href="https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/108079/area14mp/image-20160113-10417-sqrkbq.jpg"><img alt="" src="https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/108079/width237/image-20160113-10417-sqrkbq.jpg" style="width: 100%;" /></a>&#13; &#13; <figcaption><span class="caption">Magnified LCD screen.</span> <span class="attribution"><span class="source">Akpch/Wikimedia Commons</span></span></figcaption></figure><p> </p>&#13; &#13; <p>Take a look at your computer screen through a magnifying glass and you’ll see the individual pixels, each made up of three subpixels – red, green, and blue light sources. Each of these subpixels is connected via a grid of wires that criss-cross the back of the display to another circuit called a display driver. This translates incoming video data into signals that turn each subpixel on and off.</p>&#13; &#13; <p>How each pixel generates light varies depending on the technology used. Two of the <a href="https://www.cnet.com/uk/news/led-lcd-vs-oled/">most common seen today</a> are liquid crystal displays (LCDs) and organic light emitting diodes (OLEDs). LCDs use a white light at the back of the display that passes through red, green and blue colour filters. Each subpixel uses a combination of liquid crystals and polarising filters that act like tiny shutters, either letting light through or blocking it.</p>&#13; &#13; <p>OLEDs, on the other hand, are mini light sources that directly generate light when turned on. This removes the need for the white light behind the display, reducing its overall thickness, and is one of the driving factors behind the growing uptake of OLED technology.</p>&#13; &#13; <p> </p>&#13; &#13; <figure><iframe allowfullscreen="" frameborder="0" height="260" src="https://www.youtube.com/embed/AxbHpXE4VM0?wmode=transparent&amp;start=0" width="440"></iframe></figure><p> </p>&#13; &#13; <h2> ֱ̽challenges</h2>&#13; &#13; <p>Whatever technology is used, there are many individual components crammed into a relatively small space. Many smartphone displays contain more than three million subpixels, for example. Bending these components <a href="https://www.sciencedirect.com/science/article/pii/S1369702106714468">introduces strain</a>, which can tear electrical connections and peel apart layers. Current displays use a rigid piece of glass, to keep the display safe from the mechanical strains of the outside world. Something that, by design, is not an option in flexible displays.</p>&#13; &#13; <p>Organic semiconductors – the chemicals that directly produce light in OLED displays – have the additional problem of being highly sensitive to both water vapour and oxygen, gases that can pass relatively easily through thin plastic films. This can result in faded and dead pixels, leaving a <a href="https://olednet.com/oled-life-time-encapsulation/">less than desirable-looking result</a>.</p>&#13; &#13; <p>There’s also the challenge of the large-scale manufacturing of these circuits. Plastics can be tricky materials to work with. They often swell and shrink in response to water and heat, and it can be difficult to persuade materials to bond to it. In a manufacturing environment, where precise alignment and high temperature processing are critical, this can cause major issues.</p>&#13; &#13; <p>Finally, it’s not just flexible displays that need to be developed. ֱ̽components needed to power and operate the display also need to be incorporated into any overall design, placing constraints on the kinds of shape and size currently achievable.</p>&#13; &#13; <h2>What next?</h2>&#13; &#13; <p> </p>&#13; &#13; <figure class="align-right zoomable"><a href="https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/108078/area14mp/image-20160113-10419-ox462b.jpg"><img alt="" src="https://62e528761d0685343e1c-f3d1b99a743ffa4142d9d7f1978d9686.ssl.cf2.rackcdn.com/files/108078/width237/image-20160113-10419-ox462b.jpg" style="width: 100%;" /></a>&#13; &#13; <figcaption><span class="caption">Circuits patterned on a plastic substrate.</span> <span class="attribution"><span class="source">Stuart Higgins</span></span></figcaption></figure><p> </p>&#13; &#13; <p>Scientists in Japan <a href="https://www.nature.com/articles/nmat2896">have demonstrated</a> how to make electrical circuits on plastic thinner than the width of human hair in an attempt to reduce the impact of bending on circuit performance. And research into <a href="http://www.bbc.co.uk/news/science-environment-32204707">flexible batteries</a> has started to become more prevalent, too.</p>&#13; &#13; <p>Developing solutions to these problems is part of a broader area of active research, as the science and technology underlying flexible displays is also applicable to many other fields, such as <a href="https://www.theguardian.com/what-is-nano/nanotechnology-so-good-you-can-eat-it">biomedical devices</a> and <a href="https://www.theguardian.com/world/2014/sep/10/solar-energy-cells-you-can-print-out-catching-commercial-eye-says-csiro">solar energy</a>. While the challenges remain, the technology edges closer to the point where devices such as flexible displays will become ubiquitous in our everyday lives.</p>&#13; &#13; <p><img alt=" ֱ̽Conversation" height="1" src="https://counter.theconversation.edu.au/content/53143/count.gif" width="1" /></p>&#13; &#13; <p><strong><span><a href="https://theconversation.com/profiles/stuart-higgins-185645">Stuart Higgins</a>, Postdoctoral Research Associate in Optoelectronics, <em><a href="https://theconversation.com/institutions/university-of-cambridge-1283"> ֱ̽ of Cambridge</a></em></span></strong></p>&#13; &#13; <p><strong>This article was originally published on <a href="https://theconversation.com/"> ֱ̽Conversation</a>. Read the <a href="https://theconversation.com/why-are-flexible-computer-screens-taking-so-long-to-develop-53143">original article</a>.</strong></p>&#13; &#13; <p><em> ֱ̽opinions expressed in this article are those of the individual author(s) and do not represent the views of the ֱ̽ of Cambridge.</em></p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>Stuart Higgins (Cavendish Laboratory) discusses the technology being developed to create flexible displays.</p>&#13; </p></div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Stuart Higgins</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Circuits patterned on a plastic substrate</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by/4.0/" rel="license"><img alt="Creative Commons License" src="https://i.creativecommons.org/l/by/4.0/88x31.png" style="border-width:0" /></a><br />&#13; ֱ̽text in this work is licensed under a <a href="http://creativecommons.org/licenses/by/4.0/" rel="license">Creative Commons Attribution 4.0 International License</a>. For image use please see separate credits above.</p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Mon, 18 Jan 2016 12:14:32 +0000 Anonymous 165472 at First graphene-based flexible display produced /research/news/first-graphene-based-flexible-display-produced <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/news/140905-graphene-plastic-logic.gif?itok=3QJMN-a7" alt="Active matrix electrophoretic display incorporating graphene" title="Active matrix electrophoretic display incorporating graphene, Credit: Plastic Logic" /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p> ֱ̽partnership between the two organisations combines the graphene expertise of the Cambridge Graphene Centre (CGC), with the transistor and display processing steps that <a href="https://www.e-pi.com/">Plastic Logic</a> has already developed for flexible electronics. This prototype is a first example of how the partnership will accelerate the commercial development of graphene, and is a first step towards the wider implementation of graphene and graphene-like materials into flexible electronics.</p>&#13; <p>Graphene is a two-dimensional material made up of sheets of carbon atoms. It is among the strongest, most lightweight and flexible materials known, and has the potential to revolutionise industries from healthcare to electronics.</p>&#13; <p> ֱ̽new prototype is an active matrix electrophoretic display, similar to the screens used in today’s e-readers, except it is made of flexible plastic instead of glass. In contrast to conventional displays, the pixel electronics, or backplane, of this display includes a solution-processed graphene electrode, which replaces the sputtered metal electrode layer within Plastic Logic’s conventional devices, bringing product and process benefits.</p>&#13; <p>Graphene is more flexible than conventional ceramic alternatives like indium-tin oxide (ITO) and more transparent than metal films. ֱ̽ultra-flexible graphene layer may enable a wide range of products, including foldable electronics. Graphene can also be processed from solution bringing inherent benefits of using more efficient printed and roll-to-roll manufacturing approaches.</p>&#13; <p> ֱ̽new 150 pixel per inch (150 ppi) backplane was made at low temperatures (less than 100°C) using Plastic Logic’s Organic Thin Film Transistor (OTFT) technology. ֱ̽graphene electrode was deposited from solution and subsequently patterned with micron-scale features to complete the backplane.</p>&#13; <p>For this prototype, the backplane was combined with an electrophoretic imaging film to create an ultra-low power and durable display. Future demonstrations may incorporate liquid crystal (LCD) and organic light emitting diodes (OLED) technology to achieve full colour and video functionality. Lightweight flexible active-matrix backplanes may also be used for sensors, with novel digital medical imaging and gesture recognition applications already in development.</p>&#13; <p>“We are happy to see our collaboration with Plastic Logic resulting in the first graphene-based electrophoretic display exploiting graphene in its pixels’ electronics,” said Professor Andrea Ferrari, Director of the Cambridge Graphene Centre. “This is a significant step forward to enable fully wearable and flexible devices. This cements the Cambridge graphene-technology cluster and shows how an effective academic-industrial partnership is key to help move graphene from the lab to the factory floor.”</p>&#13; <p>“ ֱ̽potential of graphene is well-known, but industrial process engineering is now required to transition graphene from laboratories to industry,” said Indro Mukerjee, CEO of Plastic Logic. “This demonstration puts Plastic Logic at the forefront of this development, which will soon enable a new generation of ultra-flexible and even foldable electronics”</p>&#13; <p>This joint effort between Plastic Logic and the CGC was also recently boosted by a grant from the UK Technology Strategy Board, within the ‘realising the graphene revolution’ initiative. This will target the realisation of an advanced, full colour, OELD based display within the next 12 months.</p>&#13; <p> ֱ̽project is funded by the Engineering and Physical Sciences Research Council (EPSRC) and the EU’s Graphene Flagship.</p>&#13; </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p>A flexible display incorporating graphene in its pixels’ electronics has been successfully demonstrated by the Cambridge Graphene Centre and Plastic Logic, the first time graphene has been used in a transistor-based flexible device.</p>&#13; </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">This is a significant step forward to enable fully wearable and flexible devices</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Andrea Ferrari</div></div></div><div class="field field-name-field-media field-type-file field-label-hidden"><div class="field-items"><div class="field-item even"><div id="file-62812" class="file file-video file-video-youtube"> <h2 class="element-invisible"><a href="/file/62812">Cambridge Graphene Centre and Plastic Logic</a></h2> <div class="content"> <div class="cam-video-container media-youtube-video media-youtube-1 "> <iframe class="media-youtube-player" src="https://www.youtube-nocookie.com/embed/sn-0_RfYc_8?wmode=opaque&controls=1&rel=0&autohide=0" frameborder="0" allowfullscreen></iframe> </div> </div> </div> </div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Plastic Logic</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Active matrix electrophoretic display incorporating graphene</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p> ֱ̽text in this work is licensed under a <a href="http://creativecommons.org/licenses/by-nc-sa/3.0/">Creative Commons Licence</a>. If you use this content on your site please link back to this page. For image rights, please see the credits associated with each individual image.</p>&#13; <p><a href="http://creativecommons.org/licenses/by-nc-sa/3.0/"><img alt="" src="/sites/www.cam.ac.uk/files/80x15.png" style="width: 80px; height: 15px;" /></a></p>&#13; </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Fri, 05 Sep 2014 08:33:28 +0000 sc604 134562 at Cambridge Graphene Centre and Plastic Logic announce partnership /research/news/cambridge-graphene-centre-and-plastic-logic-announce-partnership <div class="field field-name-field-news-image field-type-image field-label-hidden"><div class="field-items"><div class="field-item even"><img class="cam-scale-with-grid" src="/sites/default/files/styles/content-580x288/public/news/news/130625-graphene-wikimedia-commons.jpg?itok=AvFGHFPh" alt="" title="Graphene., Credit: Wikimedia Commons." /></div></div></div><div class="field field-name-body field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p>A formal collaboration between Cambridge’s Graphene Centre, and the ֱ̽ spin-out company, Plastic Logic, has been announced.</p> <p>Plastic Logic will work with Cambridge researchers on a specific programme which aims to exploit graphene, related two dimensional materials and hybrid systems in flexible, plastic electronics - a field in which the UK already enjoys a world-leading position.</p> <p> ֱ̽agreement brings together two nerve-centres of technology research in Cambridge. Plastic Logic, founded in 2000, is a spin-off company from the ֱ̽’s Cavendish Research Laboratory, and develops and manufactures colour and monchrome plastic, flexible displays. ֱ̽market for these devices is expected to be worth $40bn by 2020.</p> <p> ֱ̽Cambridge Graphene Centre was established earlier this year to captalise on the ֱ̽’s ground-breaking research into the new material of the same name as well as a large class of related layered materials and hybrids. Graphene is a one atom-thick layer of graphite with remarkable potential to enable significant technological advances. ֱ̽research of the Centre aims to find ways of manufacturing and optimising graphene and related materials so that this promise can become reality.</p> <p>Plastic Logic has donated large-scale depositon equipment to the Centre to support the progression of new developments in graphene research. ֱ̽research programme itself will investigate the development of graphene as a transparent, conductive layer within flexible displays, and of novel transistor structures using layered materials, which promise to significantly improve the performance of flexible electronics.<br /> <br /> Professor Andrea Ferrari, Director of the Cambridge Graphene Centre, said: “ ֱ̽mission of our centre is to investigate the science and technology of graphene, carbon allotropes, layered crystals and hybrid nanomaterials. ֱ̽engineering innovation centre allows our partners to meet and effectively establish joint industrial-academic activities to promote innovative and adventurous research with an emphasis on applications.”</p> <p>“We welcome Plastic Logic as one of our strategic partners. Graphene and related materials are ideally suited for applications in flexible electronics and this strong synergy with a world-leading Cambridge-based company can accelerate exploitation.”</p> <p>Indro Mukerjee, CEO of Plastic Logic, said: “I am delighted that Plastic Logic is working with the world-class team at the Cambridge Graphene Centre on this transformational research programme for the application of graphene in our flexible plastic electronics process. This will enable higher levels of customisation and drive a step change in technology performance, opening up new commercial applications, such as the huge potential market for large area distributed sensors.”</p> </div></div></div><div class="field field-name-field-content-summary field-type-text-with-summary field-label-hidden"><div class="field-items"><div class="field-item even"><p><p> ֱ̽ spin-out will work with the newly-established Cambridge Graphene Centre. </p> </p></div></div></div><div class="field field-name-field-content-quote field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even">Graphene and related materials are ideally suited for applications in flexible electronics.</div></div></div><div class="field field-name-field-content-quote-name field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Andrea Ferrari</div></div></div><div class="field field-name-field-image-credit field-type-link-field field-label-hidden"><div class="field-items"><div class="field-item even"><a href="/" target="_blank">Wikimedia Commons.</a></div></div></div><div class="field field-name-field-image-desctiprion field-type-text field-label-hidden"><div class="field-items"><div class="field-item even">Graphene.</div></div></div><div class="field field-name-field-cc-attribute-text field-type-text-long field-label-hidden"><div class="field-items"><div class="field-item even"><p><a href="http://creativecommons.org/licenses/by-nc-sa/3.0/"><img alt="" src="/sites/www.cam.ac.uk/files/80x15.png" style="width: 80px; height: 15px;" /></a></p> <p>This work is licensed under a <a href="http://creativecommons.org/licenses/by-nc-sa/3.0/">Creative Commons Licence</a>. If you use this content on your site please link back to this page.</p> </div></div></div><div class="field field-name-field-show-cc-text field-type-list-boolean field-label-hidden"><div class="field-items"><div class="field-item even">Yes</div></div></div> Wed, 26 Jun 2013 11:30:40 +0000 tdk25 85662 at