̽��ֱ�� of Cambridge - Cambridge Trusts

Robotic nerve ‘cuffs’ could help treat a range of neurological conditions

sc604 — Fri, 26 Apr 2024 08:55:34 +0000

̽��ֱ��researchers, from the ̽��ֱ�� of Cambridge, combined flexible electronics and soft robotics techniques to develop the devices, which could be used for the diagnosis and treatment of a range of disorders, including epilepsy and chronic pain, or the control of prosthetic limbs.

Current tools for interfacing with the peripheral nerves – the 43 pairs of motor and sensory nerves that connect the brain and the spinal cord – are outdated, bulky and carry a high risk of nerve injury. However, the robotic nerve ‘cuffs’ developed by the Cambridge team are sensitive enough to grasp or wrap around delicate nerve fibres without causing any damage.

Tests of the nerve cuffs in rats showed that the devices only require tiny voltages to change shape in a controlled way, forming a self-closing loop around nerves without the need for surgical sutures or glues.

̽��ֱ��researchers say the combination of soft electrical actuators with neurotechnology could be an answer to minimally invasive monitoring and treatment for a range of neurological conditions. ̽��ֱ��results are reported in the journal Nature Materials.

Electric nerve implants can be used to either stimulate or block signals in target nerves. For example, they might help relieve pain by blocking pain signals, or they could be used to restore movement in paralysed limbs by sending electrical signals to the nerves. Nerve monitoring is also standard surgical procedure when operating in areas of the body containing a high concentration of nerve fibres, such as anywhere near the spinal cord.

These implants allow direct access to nerve fibres, but they come with certain risks. “Nerve implants come with a high risk of nerve injury,” said Professor George Malliaras from Cambridge’s Department of Engineering, who led the research. “Nerves are small and highly delicate, so anytime you put something large, like an electrode, in contact with them, it represents a danger to the nerves.”

“Nerve cuffs that wrap around nerves are the least invasive implants currently available, but despite this they are still too bulky, stiff and difficult to implant, requiring significant handling and potential trauma to the nerve,” said co-author Dr Damiano Barone from Cambridge’s Department of Clinical Neurosciences.

̽��ֱ��researchers designed a new type of nerve cuff made from conducting polymers, normally used in soft robotics. ̽��ֱ��ultra-thin cuffs are engineered in two separate layers. Applying tiny amounts of electricity – just a few hundred millivolts – causes the devices to swell or shrink.

̽��ֱ��cuffs are small enough that they could be rolled up into a needle and injected near the target nerve. When activated electrically, the cuffs will change their shape to wrap around the nerve, allowing nerve activity to be monitored or altered.

“To ensure the safe use of these devices inside the body, we have managed to reduce the voltage required for actuation to very low values,” said Dr Chaoqun Dong, the paper’s first author. “What's even more significant is that these cuffs can change shape in both directions and be reprogrammed. This means surgeons can adjust how tightly the device fits around a nerve until they get the best results for recording and stimulating the nerve.”

Tests in rats showed that the cuffs could be successfully placed without surgery, and formed a self-closing loop around the target nerve. ̽��ֱ��researchers are planning further testing of the devices in animal models, and are hoping to begin testing in humans within the next few years.

“Using this approach, we can reach nerves that are difficult to reach through open surgery, such as the nerves that control, pain, vision or hearing, but without the need to implant anything inside the brain,” said Barone. “ ̽��ֱ��ability to place these cuffs so they wrap around the nerves makes this a much easier procedure for surgeons, and it’s less risky for patients.”

“ ̽��ֱ��ability to make an implant that can change shape through electrical activation opens up a range of future possibilities for highly targeted treatments,” said Malliaras. “In future, we might be able to have implants that can move through the body, or even into the brain – it makes you dream how we could use technology to benefit patients in future.”

̽��ֱ��research was supported in part by the Swiss National Science Foundation, the Cambridge Trust, and the Engineering and Physical Sciences Research Council (EPSRC), part of UK Research and Innovation (UKRI).

Reference:
Chaoqun Dong et al. ‘Electrochemically actuated microelectrodes for minimally invasive peripheral nerve interfaces.’ Nature Materials (2024). DOI: 10.1038/s41563-024-01886-0

Researchers have developed tiny, flexible devices that can wrap around individual nerve fibres without damaging them.

̽��ֱ��ability to make an implant that can change shape through electrical activation opens up a range of future possibilities for highly targeted treatments

George Malliaras

XH4D via iStock / Getty Images Plus

Illustration of the human nervous system

̽��ֱ��text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. 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 main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms.

Yes

Mess is best: disordered structure of battery-like devices improves performance

sc604 — Thu, 18 Apr 2024 18:00:00 +0000

Researchers led by the ̽��ֱ�� of Cambridge used experimental and computer modelling techniques to study the porous carbon electrodes used in supercapacitors. They found that electrodes with a more disordered chemical structure stored far more energy than electrodes with a highly ordered structure.

Supercapacitors are a key technology for the energy transition and could be useful for certain forms of public transport, as well as for managing intermittent solar and wind energy generation, but their adoption has been limited by poor energy density.

̽��ֱ��researchers say their results, reported in the journal Science, represent a breakthrough in the field and could reinvigorate the development of this important net-zero technology.

Like batteries, supercapacitors store energy, but supercapacitors can charge in seconds or a few minutes, while batteries take much longer. Supercapacitors are far more durable than batteries, and can last for millions of charge cycles. However, the low energy density of supercapacitors makes them unsuitable for delivering long-term energy storage or continuous power.

“Supercapacitors are a complementary technology to batteries, rather than a replacement,” said Dr Alex Forse from Cambridge’s Yusuf Hamied Department of Chemistry, who led the research. “Their durability and extremely fast charging capabilities make them useful for a wide range of applications.”

A bus, train or metro powered by supercapacitors, for example, could fully charge in the time it takes to let passengers off and on, providing it with enough power to reach the next stop. This would eliminate the need to install any charging infrastructure along the line. However, before supercapacitors are put into widespread use, their energy storage capacity needs to be improved.

While a battery uses chemical reactions to store and release charge, a supercapacitor relies on the movement of charged molecules between porous carbon electrodes, which have a highly disordered structure. “Think of a sheet of graphene, which has a highly ordered chemical structure,” said Forse. “If you scrunch up that sheet of graphene into a ball, you have a disordered mess, which is sort of like the electrode in a supercapacitor.”

Because of the inherent messiness of the electrodes, it’s been difficult for scientists to study them and determine which parameters are the most important when attempting to improve performance. This lack of clear consensus has led to the field getting a bit stuck.

Many scientists have thought that the size of the tiny holes, or nanopores, in the carbon electrodes was the key to improved energy capacity. However, the Cambridge team analysed a series of commercially available nanoporous carbon electrodes and found there was no link between pore size and storage capacity.

Forse and his colleagues took a new approach and used nuclear magnetic resonance (NMR) spectroscopy – a sort of ‘MRI’ for batteries – to study the electrode materials. They found that the messiness of the materials – long thought to be a hindrance – was the key to their success.

“Using NMR spectroscopy, we found that energy storage capacity correlates with how disordered the materials are – the more disordered materials can store more energy,” said first author Xinyu Liu, a PhD candidate co-supervised by Forse and Professor Dame Clare Grey. “Messiness is hard to measure – it’s only possible thanks to new NMR and simulation techniques, which is why messiness is a characteristic that’s been overlooked in this field.”

When analysing the electrode materials with NMR spectroscopy, a spectrum with different peaks and valleys is produced. ̽��ֱ��position of the peak indicates how ordered or disordered the carbon is. “It wasn’t our plan to look for this, it was a big surprise,” said Forse. “When we plotted the position of the peak against energy capacity, a striking correlation came through – the most disordered materials had a capacity almost double that of the most ordered materials.”

So why is mess good? Forse says that’s the next thing the team is working on. More disordered carbons store ions more efficiently in their nanopores, and the team hope to use these results to design better supercapacitors. ̽��ֱ��messiness of the materials is determined at the point they are synthesised.

“We want to look at new ways of making these materials, to see how far messiness can take you in terms of improving energy storage,” said Forse. “It could be a turning point for a field that’s been stuck for a little while. Clare and I started working on this topic over a decade ago, and it’s exciting to see a lot of our previous fundamental work now having a clear application.”

̽��ֱ��research was supported in part by the Cambridge Trusts, the European Research Council, and UK Research and Innovation (UKRI).

Reference:
Xinyu Liu et al. ‘Structural disorder determines capacitance in nanoporous carbons.’ Science (2024). DOI: 10.1126/science.adn6242

For more information on energy-related research in Cambridge, please visit the Energy IRC, which brings together Cambridge’s research knowledge and expertise, in collaboration with global partners, to create solutions for a sustainable and resilient energy landscape for generations to come.

̽��ֱ��energy density of supercapacitors – battery-like devices that can charge in seconds or a few minutes – can be improved by increasing the ‘messiness’ of their internal structure.

This could be a turning point for a field that’s been stuck for a little while.

Alex Forse

Nathan Pitt

Left to right: Clare Grey, Xinyu Liu, Alex Forse

Yes

Does your empathy predict if you would stop and help an injured person?

cjb250 — Mon, 31 Oct 2016 11:51:39 +0000

A team of psychologists at the ̽��ֱ�� of Cambridge has conducted a social psychology experiment to test the theory that an individual’s level of empathy influences their behaviour. ̽��ֱ��results of their preliminary study, dubbed “ ̽��ֱ��Trumpington Road Study” and published in the journal Social Neuroscience, suggest that this theory is correct.

In the experiment, one of the team posed as an injured person, sitting on the grass on Trumpington Road, one the main roads running through Cambridge, next to the Cambridge ̽��ֱ�� Botanic Garden. Next to the ‘injured’ person was his upturned bicycle. Another member of the team was standing innocently across the road, watching to see if anyone was approaching from the side road of Brooklands Avenue.

As soon as a member of the public approached the street corner, alone, and was about to turn into Trumpington Road, he gave a quiet signal to the ‘injured’ person to start rubbing his ankle. ̽��ֱ��experiment had begun. ̽��ֱ��researcher across the street then noted if the passer-by stopped to ask the ‘injured’ man if he was OK.

Irrespective of whether passers-by stopped or not, once they had walked further up Trumpington Road, they were intercepted by a third researcher who told them she was conducting a ‘memory’ experiment, inviting them to describe what they had seen along the road in the last few minutes. Various items had been left on the sidewalk (such as a scarf) to make this a plausible cover story. Those who agreed to take part were also asked to visit a website in their own time, and complete the Empathy Quotient (EQ) and Autism Spectrum Quotient (AQ) questionnaires, and were told they would receive a token payment of £6 for taking part.

As the team predicted, EQ scores were higher in those who had stopped to help the injured cyclist, than in those who walked past him, presumably focused on their own agenda.

̽��ֱ��study was led by Richard Bethlehem, a Cambridge PhD student, and Professor Simon Baron-Cohen, Director of the Autism Research Centre at the ̽��ֱ�� of Cambridge. 37 (19 males, 18 females) completed both the EQ and also the AQ. They ranged in age from 18 to 77 years old.

Interestingly, how many autistic traits a person recorded was not related to whether they stopped to help or not, suggesting that empathy is the key factor, not autistic traits. Nor did age predict who stopped or not. Of those who stopped to help, 80% were female.

Richard Bethlehem said: “Experimental studies are often confined to the lab, which means they lack ‘ecological validity’. In this novel study we tested if empathy scores predict if people will act altruistically in a real-world setting. Our results support the theory that people who do good are, at least partially, driven by empathy.”

Dr Carrie Allison, a member of the team, commented: “How much empathy one has is itself a complex outcome of both biological factors and early upbringing and is a skill that can improve with development, learning, and practice.”

Professor Baron-Cohen, author of Zero Degrees of Empathy and the Chair of Trustees of the Canadian-based charity “Empathy for Peace”, said: “This research is a first step towards understanding why some people may or may not stop to help a person in distress. Studies conducted ‘in the wild’ are notoriously difficult to undertake, and even this small sample was derived from over 1,000 passers by. We will need to await a larger-scale replication. These results suggest that one factor that predicts which individuals will not stand idly by, is how many degrees of empathy they have.”

̽��ֱ��study was supported by the Autism Research Trust, the Medical Research Council, the Pinsent Darwin Trust, and the Cambridge Trust, and was conducted in association with the NIHR CLAHRC for Cambridgeshire and Peterborough NHS Foundation Trust.

Reference
Bethlehem, CA et al. Does empathy predict altruism in the wild? Social Neuroscience; 19 Oct 2016; DOI: 10.1080/17470919.2016.1249944

If you see an injured person by the side of the road, would you stop and help them, or are you more likely to walk on by? What motivates people to do good in such a situation?

How much empathy one has is itself a complex outcome of both biological factors and early upbringing and is a skill that can improve with development, learning, and practice

Carrie Allison

'Injured' cyclist on Trumpington Road

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

'Extreme sleepover #18' – rebuilding earthquake-shattered Christchurch

lw355 — Thu, 22 Sep 2016 07:49:39 +0000

At 2.30am I sit with my laptop feeling helpless as I watch video footage of a dust cloud rising around the crumbling cathedral in the city square. An earthquake has hit my hometown of Christchurch, New Zealand, and all I can do is scan the internet for snippets of information. Mild panic rises in my stomach, I have had no news of my family.

I had been woken by a text from a friend but there were no other messages, emails or missed calls. Finally I reach my mum on her mobile phone as she emerges from a central city building. She had spent three hours stuck on the tenth floor with no power, an incessant fire alarm and no safe way out. Firemen arrived to help her and stranded colleagues negotiate the dark internal stairwells that had pulled away from the walls, with water pouring from broken water pipes above.

We speak only briefly to keep the airways free for others, but I at least learn that my immediate family are okay. After the boost of adrenaline, I can’t sleep. A few hours later, feeling a little lost, I set off for rowing training as life around me in Cambridge surreally continues as normal.

That was 2011 and at the time I was completing an MPhil degree in the Engineering Department. Following my degree, I returned to New Zealand to work on the reconstruction of Christchurch, feeling motivated that as an engineer I could contribute towards rebuilding the city.

I experienced the aftershocks (which numbered in the thousands) and became adept at estimating the epicentre through the sound and feel of the shaking. Life was fairly normal living on the western side of the city where there was minimal damage. However, I worked in badly damaged areas in the east, where houses had tilted on their foundations and the roads were rough and potholed from liquefaction damage.

Partway through the year I was offered funding for a PhD back in Cambridge. I saw an opportunity to research the reconstruction as it progressed and to capture insights as to why and how decisions were made. I believed I could continue to make a meaningful contribution, albeit shifting to the role of observer rather than as a direct participant in the recovery process.

My research involved returning to Christchurch for fieldwork each year, interviewing engineers, executives, political leaders and other professionals involved in planning and implementing the reconstruction.

̽��ֱ��initial shift from practitioner to researcher was a personal challenge. I felt I had to prove my relevance to the rebuild effort to those dealing with the stresses and challenges of the process every day. However, my fears gradually dissipated – I was welcomed back and people were happy to spend time with me to reflect on their experiences. Sometimes it was also a chance to vent their frustrations.

I had initially considered conducting multiple case studies around the world, but soon realised the value of a longer-term study in Christchurch to capture changes over time. Also, as a PhD student with limited time and budget, it made sense to work in a region where I had a good understanding of the politics and the culture and a connection to people through shared experience.

Securing interviews with critical decision makers involved planning (sometimes years in the process) and a little luck. During field visits I had an allocated desk at one of the major recovery organisations and attended community and industry events. This meant I could immerse myself in recovery discussions and I had opportunities to join meetings simply because I was in the office at the right time.

On my final visit I met with the central government minister in charge of the recovery. We discussed major decisions made by the government in response to the earthquakes. This included the establishment of new legislation, the creation of new organisations to lead the recovery and the red zoning of residential land, where approximately 8,000 residential properties now sit empty as their future is debated.

One of the many challenges of the recovery was the need to create new organisations to lead the process and to interpret ambiguous policy statements regarding funding commitments. Although there were long processes of negotiation (establishing clear funding arrangements, for example, took years), a pre-defined, prescriptive approach could have been equally unsatisfactory.

Five years into the recovery, there is a lingering question over how to be better prepared in the future. There is a need to create policies that provide both appropriate clear guidance and flexibility to respond to specific circumstances. This remains the subject of much debate in New Zealand. Despite the country’s relatively advanced system for emergency management, it was caught off-guard by a large earthquake in Christchurch.

My research has shown that while post-disaster reconstruction may be considered an opportunity to rebuild more resilient infrastructure, many potential opportunities may be excluded. Contributing factors include financial constraints, limits in scope of organisations involved and the inherent challenge of introducing change to communities, particularly in the time-constrained context of recovery.

With a better understanding of such factors, we can gain better insight into the effectiveness of different decisions and subsequent pathways for recovery. Unfortunately, with natural disasters like earthquakes, there is no prevention; there is only preparation for the next time disaster strikes.

Kristen was primarily funded through a Cambridge International Scholarship from the Cambridge Trusts. She also received small grants from the Earthquake Commission in New Zealand, the Department of Engineering, Corpus Christi College and the Cambridge Philosophical Society. Her PhD was supervised by Professor Peter Guthrie.

Kristen MacAskill describes how an earthquake in her hometown served to influence her career as an engineer.

Houses had tilted on their foundations and the roads were rough and potholed from liquefaction damage

Kristen MacAskill

Martin Luff

A badly damaged house in North New Brighton, Christchurch, New Zealand

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Licence type:

Attribution-ShareAlike