̽��ֱ�� of Cambridge - ̽��ֱ�� of Surrey

Lights could be the future of the internet and data transmission

Anonymous — Tue, 25 Jul 2023 14:38:40 +0000

New internet technologies are being rapidly refined, and LED-based communication links are expected to be used in services and scenarios including Light-fidelity (Li-Fi), underwater communications, moderate- to high-speed photonic connections and various ‘Internet of Things’ (IoT) devices.

A study, led by the Universities of Surrey and Cambridge and published in the journal Nature Photonics, has investigated how to release high-speed photonic sources using materials known as metal-halide perovskites. These semiconductors are studied with LEDs for their excellent optoelectronic properties and low-cost processing methods.

“IoT devices have the potential to add significant value to industry and the global economy,” said corresponding author Dr Wei Zhang from the ̽��ֱ�� of Surrey. “In this market, costs and compatibility are often prioritised over data transmission speed and scientists are looking for alternative ways to reduce energy consumption per bit and improve compactness while simultaneously working on improving the speed of data connection.

“In our study, we have shown how metal-halide perovskites could provide a cost-efficient and powerful solution to make LEDs which have enormous potential to increase their bandwidths into the gigahertz levels.

“Our investigations will accelerate the development of high-speed perovskite photodetectors and continuous wave-pumped perovskite lasers, opening up new avenues for advancements in optoelectronic technologies.”

“This is a significant step toward perovskite light sources for next-generation data communications,” said co-first author Hao Wang, a PhD candidate in Cambridge’s Department of Engineering. “It also paves the way for the integration of perovskites with micro-electronics platforms, presenting new opportunities for seamless integration and advancement in the field of data communications.”

̽��ֱ��project involved researchers from Oxford, Bath, Warwick, UCL, EMPA and UESTC.

Reference:
Aobo Ren, Hao Wang et al. ‘High-bandwidth perovskite photonic sources on silicon.’ Nature Photonics (2023). DOI: 10.1038/s41566-023-01242-9

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.

Adapted from a ̽��ֱ�� of Surrey press release.

Fast data transmission could be delivered in homes and offices through light emitting diode (LED) bulbs, complementing existing communication technologies and networks.

This is a significant step toward perovskite light sources for next-generation data communications

Hao Wang

Yaorusheng via Getty Images

Abstract colourful background

̽��ֱ��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 – as here, 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.

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Curbing COVID-19 in schools: Cambridge scientists support CO2 monitor rollout

sc604 — Mon, 17 Jan 2022 12:44:06 +0000

Scientists from Cambridge, Surrey and Imperial College London are supporting the rollout of portable monitors to UK schools as part of project CO-TRACE. ̽��ֱ��researchers behind the collaboration have produced materials to help teachers use the monitors, which have been rolled out to schools nationwide.

̽��ֱ��level of carbon dioxide (CO₂) in a closed space is a good indicator of air quality and can signpost the need for ventilation. As the virus that causes COVID-19 is airborne, ensuring the air is properly refreshed using ventilation is crucial for reducing its spread. ̽��ֱ��device displays levels of CO2 and colour coding to indicate good, normal, or poor ventilation. Well ventilated spaces should have CO2 levels consistently below 800 parts per million (ppm), with readings above 1500ppm indicating poor ventilation or overcrowding.

“CO2 monitors allow teachers to assess the ventilation in their classrooms for the first time,” said Imperial’s Dr Henry Burridge, co-investigator on the project. “This is especially important during colder months when ventilation is typically lower due to colder outdoor temperatures, causing COVID-19 and other airborne diseases like the common cold and flu to linger and spread more easily.”

̽��ֱ��monitors mean teachers can see CO2 levels change in real-time as windows are opened and air is refreshed, allowing them to balance ventilation and warmth. Teachers can also use the monitors to know when it is safe to close windows slightly, which could help them keep classrooms more comfortable. As well as being a good ‘proxy’ for ventilation, lower CO2 levels have been linked to improved learning outcomes and better cognitive performance.

̽��ֱ��team behind the CO-TRACE project uses experimental modelling, numerical simulations, full-scale observations, and infection risk modelling to understand how the potential for COVID-19 spread changes with indoor air flows, ventilation levels, and the number of people in a space. In 2021, the researchers used monitored CO2 to indicate how much exhaled breath was present within classrooms, and their models found that seasonal variation in classroom ventilation levels could lead to airborne infection risks in winter being roughly double those in summer. This highlights that monitoring excess CO2 could be of significant benefit in mitigating airborne infection risk.

̽��ֱ��portability of the CO2 monitors, supplied by the Department for Education (DfE), means schools can move them around to test different areas, starting with those they suspect may be poorly ventilated.

“ ̽��ֱ��monitors empower teachers to strike a balance between good ventilation and warmth during winter,” said Professor Paul Linden from Cambridge’s Department of Applied Mathematics and Theoretical Physics, co-investigator on the programme. “We are pleased that the Government is taking evidence-based action to address air quality and COVID-19 spread in schools.”

̽��ֱ��monitors are accompanied by advice from the project which guides appropriate actions from teacher based on the CO2 readings in classrooms. Recommendations include opening higher windows before lower ones, and closing windows slowly when ventilation is good.

Schools with areas that are consistently low in air quality despite ventilation should consider using air cleaners. For such schools, the DfE is distributing between 7,000 and 8,000 air cleaning units.

When the project was announced in 2021, then-Education Secretary Gavin Williamson said: “Providing all schools with CO2 monitors will help them make sure they have the right balance of measures in place, minimising any potential disruption to education and allowing them to focus on world-class lessons and catch up for the children who need it. By keeping up simple measures such as ventilation and testing, young people can now enjoy more freedom at school and college.”

̽��ֱ��project is funded by the EPSRC, part of UK Research and Innovation (UKRI).

Adapted from an Imperial College story.

UK schools have received more than 300,000 CO2 monitors as part of a government initiative to reduce COVID-19 spread in classrooms.

̽��ֱ��monitors empower teachers to strike a balance between good ventilation and warmth during winter

Paul Linden

Olivier Le Moal

CO2 monitor

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 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 – as here, 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

Risk of Ebola outbreaks could be reduced by understanding how ecosystems influence human health

Anonymous — Tue, 15 Oct 2019 15:00:00 +0000

̽��ֱ��model could help policymakers to decide where to target vaccine deployment, or develop healthcare infrastructure, to reduce the risk of zoonotic disease outbreaks – illnesses that spread between animals and humans.

Analysis using the mathematical model, published in the journal Nature Communications, shows that several countries in Africa, including Nigeria, could be at risk of Ebola outbreaks both presently and in the future, despite having experienced no known cases to date.

“It is vital that we understand the complexities causing animal-borne diseases to spill-over into humans, to accurately predict outbreaks and help save lives,” said Dr David Redding at UCL Genetics, Evolution & Environment, first author of the study. “In our models, we’ve included more information about the animals that carry Ebola and, by doing so, we can better account for how changes in climate, land-use or human societies can affect human health.”

Designed by a team including researchers from UCL, ̽��ֱ�� of Cambridge and Zoological Society of London (ZSL), the model captures the impact of climate, land use and human population factors on the risk of Ebola and predicts the known set of previous outbreaks with a high degree of accuracy, even in the absence of case data. ̽��ֱ��results show that Ebola outbreaks, resulting from spill-over events, are 1.6 times more likely in scenarios with increased warming and slower socioeconomic development.

Professor James Wood from Cambridge’s Department of Veterinary Medicine, who co-authored the study, said: “This work takes an unusually long-term approach to considering epidemic risk of Ebola, and identifies risks likely increasing across West as well as Central Africa. While there is always inherent uncertainty in specific predictions, the results suggest investment in primary health care across sub-Saharan Africa could have the most beneficial impact in reducing future risk.”

More than two thirds of all infectious diseases originate in animals, including Ebola, Lassa fever and West Nile virus. These diseases contribute to the global health and economic burden that disproportionately affects poor communities.

̽��ֱ��latest Ebola epidemic has claimed more than 2,100 lives since August 2018 and while there are signs it is in retreat, the risk of spread is still high according to a recent report by the UN.

̽��ֱ��World Bank estimates that the 2014 Ebola outbreak cost the three countries most affected many billions of dollars, due to infrastructure breakdown, mass migration, crop abandonment and a rise in endemic disease due to overrun healthcare systems, among other drivers.

̽��ֱ��team used a first principles approach of how humans interact with wildlife and how Ebola spreads within human populations to develop the predictive framework, which could also be adapted for other zoonotic diseases.

“Importantly, our model is flexible enough to allow us to predict Ebola outbreaks in alternative, simulated versions of the world. For example, we examine a set of plausible future environments and show stark differences in how Ebola responds to the best-case and worst-case scenarios of future climate change and poverty alleviation,” explained co-author Professor Kate Jones at UCL Genetics, Evolution & Environment and Institute of Zoology, ZSL.

̽��ֱ��study was funded by the Natural Environmental Research Council, Economic and Social Research Council, the Medical Research Council, the Royal Society and the Wellcome Trust.

Reference:
Redding, DW et al. 'Understanding the impact of environmental and socio-economic factors on emergence and epidemic potential of Ebola in Africa’, Nature Communications (2019), DOI: 10.1038/s41467-019-12499-6.

Adapted from a press release by UCL.

̽��ֱ��next Ebola outbreak could be predicted using a new model that tracks how changes to ecosystems and human societies combine to affect the spread of the deadly infectious disease.

̽��ֱ��results suggest investment in primary health care across sub-Saharan Africa could have the most beneficial impact in reducing future Ebola risk.

James Wood

UN Photo/Martine Perret

Ebola treatment centre, Nzérékoré, Guinea

Yes

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