17th February 2023

The Indian Institute of Science (IISc) will throw open its gates to visitors on the occasion of Open Day to be held on Saturday, 4 March 2023, after a gap of two years.   

Open Day is typically organised close to the birth anniversary of the Founder, JN Tata, as well as National Science Day. This year, on 4 March 2023, from 9 am to 5 pm, people from all walks of life are invited to explore the campus and catch a glimpse of the exciting research conducted here.   

On this day, students and researchers at the Institute will showcase their work as well as new and exciting advances in science and technology for visiting enthusiasts. The Institute will be abuzz with popular lectures, panel discussions, quizzes and competitions. Each Department and Centre will put forth experimental demonstrations, interactive exhibits and colourful posters.   

“Through Open Day, we hope to share the excitement of science and engineering with every visitor, and inspire them to develop the scientific temper necessary to become a responsible citizen of the modern world,” said Prof G Rangarajan, Director, IISc.   

There will be e-rickshaws (Transvahan) available for easy commute inside the campus and helpdesks will be located at several points. Visitors are requested to help keep the campus clean by making full use of the garbage bins placed everywhere, and by bringing their own water bottles (drinking water refill stations will be available across campus).  

Entry to Open Day is free. Although registration is not mandatory, educational and other institutions as well as individual members of the public are strongly encouraged to register for the event at the following links:  

Institutional registration:
https://docs.google.com/forms/d/e/1FAIpQLSeWgGcFw3Ve71wLmk4N6SFOEBKPE4yF_NPTHD4INHrXD-TG9g/viewform

Individual registration:
https://docs.google.com/forms/d/e/1FAIpQLScEcJv27vczidKG5NUaX1G7LrWQM0kcrBXMnGhKQaRGrUVAFA/viewform

For more details about Open Day, please visit https://openday.iisc.ac.in

Contact: 

Public Relations Office
Indian Institute of Science (IISc)
pro@iisc.ac.in | 080-2293 2770

In a new study, researchers at the Indian Institute of Science (IISc) show how a brain-inspired image sensor can go beyond the diffraction limit of light to detect miniscule objects such as cellular components or nanoparticles invisible to current microscopes. Their novel technique, which combines optical microscopy with a neuromorphic camera and machine learning algorithms, presents a major step forward in pinpointing objects smaller than 50 nanometers in size. The results are published in Nature Nanotechnology.

Since the invention of optical microscopes, scientists have strived to surpass a barrier called the diffraction limit, which means that the microscope cannot distinguish between two objects if they are smaller than a certain size (typically 200-300 nanometers). Their efforts have largely focused on either modifying the molecules being imaged, or developing better illumination strategies – some of which led to the 2014 Nobel Prize in Chemistry. “But very few have actually tried to use the detector itself to try and surpass this detection limit,” says Deepak Nair, Associate Professor at the Centre for Neuroscience (CNS), IISc, and corresponding author of the study.

Transformation of cumulative probability density of ON and OFF processes allows localisation below the limit of classical single particle detection (Credit: Mangalwedhekar et al, 2023)

Measuring roughly 40 mm (height) by 60 mm (width) by 25 mm (diameter), and weighing about 100 grams, the neuromorphic camera used in the study mimics the way the human retina converts light into electrical impulses, and has several advantages over conventional cameras. In a typical camera, each pixel captures the intensity of light falling on it for the entire exposure time that the camera focuses on the object, and all these pixels are pooled together to reconstruct an image of the object. In neuromorphic cameras, each pixel operates independently and asynchronously, generating events or spikes only when there is a change in the intensity of light falling on that pixel. This generates sparse and lower amount of data compared to traditional cameras, which capture every pixel value at a fixed rate, regardless of whether there is any change in the scene. This functioning of a neuromorphic camera is similar to how the human retina works, and allows the camera to “sample” the environment with much higher temporal resolution – because it is not limited by a frame rate like normal cameras – and also perform background suppression.

“Such neuromorphic cameras have a very high dynamic range (>120 dB), which means that you can go from a very low-light environment to very high-light conditions. The combination of the asynchronous nature, high dynamic range, sparse data, and high temporal resolution of neuromorphic cameras make them well-suited for use in neuromorphic microscopy,” explains Chetan Singh Thakur, Assistant Professor at the Department of Electronic Systems Engineering (DESE), IISc, and co-author.

View of the microscopy setup (Credit: Rohit Mangalwedhekar)

In the current study, the group used their neuromorphic camera to pinpoint individual fluorescent beads smaller than the limit of diffraction, by shining laser pulses at both high and low intensities, and measuring the variation in the fluorescence levels. As the intensity increases, the camera captures the signal as an “ON” event, while an “OFF” event is reported when the light intensity decreases. The data from these events were pooled together to reconstruct frames.

To accurately locate the fluorescent particles within the frames, the team used two methods. The first was a deep learning algorithm, trained on about one and a half million image simulations that closely represented the experimental data, to predict where the centroid of the object could be, explains Rohit Mangalwedhekar, former research intern at CNS and first author of the study. A wavelet segmentation algorithm was also used to determine the centroids of the particles separately for the ON and the OFF events. Combining the predictions from both allowed the team to zero in on the object’s precise location with greater accuracy than existing techniques.

“In biological processes like self-organisation, you have molecules that are alternating between random or directed movement, or that are immobilised,” explains Nair. “Therefore, you need to have the ability to locate the centre of this molecule with the highest precision possible so that we can understand the thumb rules that allow the self-organisation.” The team was able to closely track the movement of a fluorescent bead moving freely in an aqueous solution using this technique. This approach can, therefore, have widespread applications in precisely tracking and understanding stochastic processes in biology, chemistry and physics.

REFERENCE:

Mangalwedhekar R, Singh N, Thakur CS, Seelamantula CS, Jose M, Nair D, Achieving nanoscale precision using neuromorphic localization microscopy, Nature Nanotechnology (2023).

https://www.nature.com/articles/s41565-022-01291-1

CONTACT:

Deepak Nair
Associate Professor
Centre for Neuroscience (CNS)
Indian Institute of Science (IISc)
Email: deepak@iisc.ac.in
Phone: 080-22933535
Website: https://cns.iisc.ac.in/deepak/index.html

Chetan Singh Thakur
Assistant Professor
Department of Electronic Systems Engineering (DESE)
Indian Institute of Science (IISc)
Email: csthakur@iisc.ac.in
Phone: 080-22933608
Website: https://labs.dese.iisc.ac.in/neuronics/

IMAGE CAPTIONS AND CREDITS:

Image 1: Transformation of cumulative probability density of ON and OFF processes allows localisation below the limit of classical single particle detection (Credit: Mangalwedhekar et al, 2023)

Image 2: View of the microscopy setup (Credit: Rohit Mangalwedhekar)

NOTE TO JOURNALISTS:

a) If any of the text in this release is reproduced verbatim, please credit the IISc press release.
b) For any queries about IISc press releases, please write to news@iisc.ac.in or pro@iisc.ac.in.

23 February 2023

– Kaustubh Roy

Lightning strikes can be dangerous for aircraft. But studying this phenomenon in the field is quite difficult. Researchers at the Indian Institute of Science (IISc) have developed a unique computational model to simulate how lightning can strike an aircraft. The insights they have gleaned from this model can help design better lightning protective measures for aircraft.

Lightning strikes can damage the aircraft surface, lead to temporary disruptions in electrical and electronic systems or even cause permanent damage, and in extreme cases, cause ignition of the fuel-air mixture around the engine, leading to an explosion. “Usually, an aircraft gets struck by lightning once every 1,000 hours,” says Udaya Kumar, Professor at the Department of Electrical Engineering, IISc, whose lab has been investigating this phenomenon in recent years. “There have been a lot of incidents in the last century where things have been very catastrophic.”

The first step in protecting aircraft from lightning is identifying the most common regions on the aircraft where lightning can attach or hit. Kumar and his team realised that current approaches to this identification were grossly oversimplified, and set out to develop a more comprehensive computational model. The model and the data obtained from it have been published in Atmosphere.

Kumar’s lab has been studying lightning protection for the past few years. In previous studies, his team has analysed the effectiveness of lightning rods in safeguarding tall buildings in a thunderstorm. They have developed unique models that have addressed several long-standing issues of lightning current evolution. In the past, he was also involved in the design of a lightning protective system for Indian satellite launch pads and has conducted research on different protective schemes.  In the current study as well as in ongoing work, they have focused on modelling how lightning impacts aircraft, in order to develop suitable protective measures.

In the usual downward cloud-to-ground lightning, leaders – precursors to lightning arcs – are initiated at the cloud, which propagate towards the ground. However, field data, as well as the model developed, clearly show that in more than 90% of the cases, the leader discharges are initiated at the aircraft. The model developed by the IISc team is applied to two different aircraft geometries: a DC10 passenger aircraft and the SDM fighter aircraft model. It involves extensive computation of the electric field around the aircraft and suitable modelling of the electrical discharges.

With the model, the scientists were able to obtain estimates of the minimum ambient electric field required for initiation of lightning leader discharges from the aircraft. These values, the researchers say, are in good agreement with measured data from instrumented aircraft flown through thunderstorms, such as NASA’s Storm Hazard Program. Moreover, the aircraft is not perfectly parallel to the ground during take-off and landing, and the model is able to simulate how these changes in orientation can affect the electric field. The role of atmospheric conditions such as humidity and air pressure are also taken into account in the model. It also showed that aircraft at higher altitudes had a greater affinity for lightning strikes.

In ongoing studies, the team is planning to investigate several related issues. Firstly, what could be the peak value of the lightning stroke current for aircraft-initiated lightning? Secondly, what could be the local changes around the aircraft during the lightning strike evolution? In addition, they are investigating disruptions to the internal electrical equipment when struck by lightning. Kumar’s lab has also carried out a first-of-its-kind experiment on a small military aircraft by injecting it with enormous amounts of current – intended to emulate lightning discharge – and by collecting electric field data from inside the craft.

Kumar and his team suggest that such studies can aid in reliable quantification of the lightning threat, and enable optimised design of lightning protective measures.

REFERENCES: 

Das S, Kumar U, Modeling of Bi-Polar Leader Inception and Propagation from Flying Aircraft Prior to a Lightning Strike, Atmosphere (2022) 

https://doi.org/10.3390/atmos13060943 

Das S, Kumar U, Comparative analysis for inception of positive connecting leader from a cruising and grounded aircraft, 2022 36th International Conference on Lightning Protection (ICLP)  

https://ieeexplore.ieee.org/document/9942520 

Das S, Kumar U, Quantitative study on efficacy of lightning rod on building, 2022 IEEE International Conference on High Voltage Engineering and Applications (ICHVE) 

https://ieeexplore.ieee.org/document/9961455/ 

CONTACT: 
Udaya Kumar
Professor and Chair, Department of Electrical Engineering
Indian Institute of Science (IISc)
udayk@iisc.ac.in
Phone: +91 80 2293 3177
Website:  https://ee.iisc.ac.in/~uday/  
IMAGE CAPTION AND CREDIT:   
Tejas under lightning current injection experiment (Image courtesy: Udaya Kumar)

NOTE TO JOURNALISTS: 

a) If any of the text in this release is reproduced verbatim, please credit the IISc press release.
b) For any queries about IISc press releases, please write to news@iisc.ac.in or pro@iisc.ac.in.

02 March 2023

–Gowri R

In a recent study, researchers from the Department of Organic Chemistry (OC) and Materials Research Centre (MRC), Indian Institute of Science (IISc), show that surface modifications of two-dimensional molybdenum disulphide (2D-MoS₂) nanosheets can make them highly effective for applications like delivering drugs to diseased cells.

Nanomaterials usually need to be modified or customised depending on the application to improve their efficiency. Typically, they are chemically modified through a process called functionalisation, which involves attaching ligands (small or large molecules) to the surface of the nanomaterial.

In the new study, the researchers modified the surface of 2D-MoS₂ nanosheets with thiol (sulphur-containing) ligands. They found that these thiols can be exchanged with naturally-occurring thiols in biological systems, which could allow drugs attached to these nanosheets to be released. These chemically-modified nanosheets were also found to be safe to use inside living cells.

a) Schematic representation of thiol exchange scheme which shows the fluorescence DOX released in presence of Glutathione (GSH) molecule. b) Selectivity of thiol exchange with thiols compared to disulphides. Precipitation was clearly observed for thiols like Cysteamine (CSA), Glutathione (GSH), Mercaptopropionic acid (MPA). However Lipoic acid (LA), a disulphide shows no precipitation which indicate no significant thiol exchange. c) Release of fluorescent DOX in cancer cells confirmed through confocal imaging. d) Canonical score plot for successful discrimination of various bio-thiols.

“Our study shows that thiol exchange on 2D-MoS₂ nanosheets is effective, and the nanomaterial is stable in the presence of various biomolecules. This is an important observation as it will make this nanomaterial highly beneficial for biomedical applications like drug delivery,” explains Mrinmoy De, Associate Professor at the Department of Organic Chemistry and senior author of the study published in ACS Nano.

The team first used a fluorescent thiol called boron-dipyrromethene (BOD-SH) to modify the surface of the 2D-MoS₂ nanosheets in order to create a functionalised version (BOD-MoS₂). Then, they tested the possibility of thiol-to-thiol exchange on BOD-MoS₂ using glutathione (GSH) – a naturally occurring thiol found in abundance in cancer cells. They found that GSH molecules swapped places with BOD-SH on the surface of the nanosheet – a process that they confirmed using fluorescence techniques.

When the researchers attached an anti-cancer drug named doxorubicin (DOX) to the nanosheet surface, they found that thiol exchange could also happen between GSH and DOX, allowing DOX to get dropped off at the diseased site. Because the exchange happens only in the presence of high concentrations of GSH found in diseased cells, drugs like DOX can be delivered specifically to cancer cells without affecting normal cells, which can also potentially reduce any side effects.

Previous efforts have focused on using gold nanoparticles for such biomedical applications, according to the researchers, but these nanoparticles are expensive and have limited efficiency due to their non-selectivity between mono thiols and disulphides. “Our experiments show that 2D-MoS₂ nanosheets can be an effective substitute for gold nanoparticles, and they will be greatly beneficial in the field of nanomedicine,” says Pradipta Behera, a postdoctoral research scholar at IISc and the first author of the study.  The MoS₂ nanosheets were found to be stable in the presence of biofluids. They also have a higher surface area than gold nanoparticles, which means that they can be more efficient.

Moving forward, the team plans to work on improving the stability of the nanomaterial in the presence of various thiol-containing liquids and exploring alternative surface modification approaches to customise the nanosheets for other applications. “This work on 2D-MoS₂ nanosheets can be developed in the future as an alternative to RNA and DNA delivery applications, which can be useful for detecting and treating infections such as COVID-19,” adds Behera.

REFERENCE:

Behera P, Karunakaran S, Sahoo J, Bhatt P, Rana S, & De M, Ligand Exchange on MoS₂ Nanosheets: Applications in Array-Based Sensing and Drug Delivery, ACS Nano (2022).

https://pubs.acs.org/doi/10.1021/acsnano.2c06994

 CONTACT:
Mrinmoy De
Associate Professor
Department of Organic Chemistry
Indian Institute of Science (IISc)
Email: md@iisc.ac.in
Phone: +91-80-2293-2042 (Office) / 2436 (Lab)
Website: https://orgchem.iisc.ac.in/mrinmoy_de/

Credit: Pradipta Behera

NOTE TO JOURNALISTS:

1. a) If any of the text in this release is reproduced verbatim, please credit the IISc press release.
2. b) For any queries about IISc press releases, please write tonews@iisc.ac.inor pro@iisc.ac.in.

9th March 2023

– Ranjini Raghunath 

Soils are reliable sinks for trapping carbon, which is key to mitigating the effects of climate change. Grazing by large mammals favours soil carbon storage in grasslands, but around the world, wild herbivores are gradually being replaced by livestock. In the Spiti region of the Himalaya, researchers at the Centre for Ecological Sciences (CES), Indian Institute of Science (IISc) have found that grazing by livestock leads to lower carbon storage in soil compared to grazing by wild herbivores.

Part of this difference appears to be due to the use of veterinary antibiotics such as tetracycline on livestock. When released into the soil through dung and urine, these antibiotics alter the microbial communities in soil in ways that are detrimental for sequestering carbon. In such areas, “rewilding” the soils – restoring beneficial microbes lost due to antibiotics – could help offset the damage, the researchers say. Quarantining animals that are given antibiotics until the medicines pass out of their system could also help reduce their impact on soil.

One reason why soil health deteriorates under grazing by domestic livestock compared to wild herbivores is because of antibiotics (Credit: Sumanta Bagchi)

“Today, livestock are the most abundant large mammals on Earth,” says Sumanta Bagchi, Associate Professor at CES and corresponding author of the study published in Global Change Biology. “If the carbon stored in soil under livestock can be increased by even a small amount, then it can have a big impact on climate mitigation.”

In a previous study, the researchers had shown how grazing by herbivores plays a crucial role in stabilising the pool of soil carbon in the same region. In the current study, they set out to ask the question: Are livestock such as sheep and cattle similar or different in how they affect the soil carbon stocks compared to their wild relatives such as the yak and ibex?

To answer this, the researchers studied soils over 16 years in areas grazed by wild herbivores and by livestock respectively, and analysed them for various parameters including microbial composition, soil enzymes, carbon stocks, and the amount of veterinary antibiotics. “This is part of a long-term study on ecosystem functions and climate change in the Himalaya, which was started in 2005,” explains Bagchi.

Although soils from the wild and livestock areas had many similarities, they differed in one key parameter called carbon use efficiency (CUE), which determines the ability of microbes to store carbon in the soil. The soil in the livestock areas had 19% lower CUE.

When they probed further for potential explanations, the researchers found that the soil microbial composition in areas with livestock was different from the areas with wild herbivores. Finally, they also found higher levels of antibiotic residues in soil under livestock. “This highlights how human land use, antibiotics, microbes, soils, and climate change are deeply connected,” says Dilip Naidu, PhD student at the Divecha Centre for Climate Change, IISc, and an author of the study.

“What is interesting,” Bagchi adds, “is that antibiotic usage in pastoral ecosystems like Spiti is fairly low.” The situation could be worse in areas where livestock are reared at large scales, and where they are often given antibiotics even when they are not sick, he points out. Antibiotics such as tetracycline are long-lived and can linger in the soil for decades. “Their unregulated use not only threatens climate but also poses the risk of evolution of antibiotic resistance in pathogens that can cause difficult-to-treat infections in humans and animals,” says Shamik Roy, former PhD student at IISc and lead author of this study.

“We do not yet fully understand the details of the underlying mechanisms of how soil microbial communities respond to the antibiotics, and whether they can be restored easily,” adds Roy. In future studies, the researchers plan to investigate how better management of livestock can mitigate their negative impacts on the environment, alongside microbial restoration.

REFERENCE:

Roy S, Naidu DGT, Bagchi S, Functional substitutability of native herbivores by livestock for soil carbon stock is mediated by microbial decomposers, Global Change Biology (2023).

https://onlinelibrary.wiley.com/doi/10.1111/gcb.16600

CONTACT: 
Sumanta Bagchi
Associate Professor
Centre for Ecological Sciences (CES)
Indian Institute of Science (IISc)
sbagchi@iisc.ac.in
080-22933528

NOTE TO JOURNALISTS:

1. a) If any of the text in this release is reproduced verbatim, please credit the IISc press release.
2. b) For any queries about IISc press releases, please write to news@iisc.ac.inor pro@ac.in.

17 March 2023

The State Bank of India (SBI), under its Corporate Social Responsibility (CSR) activities, has partnered with the Indian Institute of Science (IISc), Bengaluru, towards the construction of the Orthopaedics Wing of the Bagchi-Parthasarathy hospital coming up on campus. An MoU was signed by SBI and IISc at the Institute on 16 March 2023.

The not-for-profit multispecialty hospital planned at IISc will support the world class clinical training of MD-PhD/MS-PhD students, while providing an unprecedented platform for advanced research at the intersection of science, engineering and medicine. In addition to delivering the highest quality care to society at large, the hospital aims to also provide state-of-the-art facilities for diagnostics, treatment and research. There will be 832 ward beds split into general beds and special beds (single and shared occupancy). The hospital will have 19 major Operation Theatres (OTs) for super specialty surgeries, and 6 minor OTs. Advanced radiology and imaging services such as CT, MRI, PET-CT, Mammography, USG and Doppler, and X-ray would be available.

SBI will provide a CSR donation of Rs 24 crore for the establishment of the Orthopaedics Wing, including the required biomedical equipment. The project will be completed by 2025.

Dignitaries present at the MoU signing ceremony included Mr Nand Kishore, SBI Chief General Manager; Mr Sandeep Bhatnagar, General Manager (Network-II); Mr Alok Kumar Dwivedi, Deputy General Manager and Circle Development Officer; Mr Murali Krishna VRM, Deputy General Manager (B&O), Bengaluru North, and Prof Govindan Rangarajan, Director of IISc, as well as other SBI officials.

CONTACT 
Office of Communications | news@iisc.ac.in

20 March 2023

– Narmada Khare

In January 2022, around the time that the Omicron variant of SARS-CoV-2 started spreading rapidly, a team of researchers at the Indian Institute of Science (IISc) led by Shashank Tripathi, Assistant Professor at the Department of Microbiology & Cell Biology, and Centre for Infectious Diseases Research, noticed that there was an unusually high increase in the number of recombinant strains of the Omicron variant.

The team analyzed genomic sequences of all the viral strains that appeared between November 2019 and July 2022 in various databases worldwide. In a study published in the Journal of Medical Virology, they have identified several new mutations that accumulated through recombination at a high rate and affected viral proteins, especially different parts (domains) of the viral spike protein. These domains – such as the Receptor Binding Domain (RBD) and N Terminal Domain (NTD) – are known to be involved in the virus-host binding and have also been reported as sites of attack by the host’s immune system. The team showed that, with the aid of these mutations, several such Omicron recombinant and mutant strains were able to escape from the host’s defenses and bind more tightly to the host cell.

Their observations add to growing evidence about how efficient new strains of the virus are at escaping immune attack and at causing infections.

Recombination in SARS-CoV-2 viruses (Credit: Rishad Shiraz) 

Viruses like SARS-CoV-2 are known to change constantly, making it hard for our immune system to identify and destroy them. This is a major concern when generating vaccines. The genetic material in SARS-CoV-2 is a long single-stranded RNA. In addition, the protein that is required to make copies of this RNA – RNA polymerase – is known to be error-prone in this virus.

Viruses can evolve via one of two mechanisms: mutation or recombination, explains Tripathi. “This is a strategy to increase its genetic diversity.” The polymerase doesn’t just allow mutations to accumulate, it often also causes recombination to happen between different strains of the virus. This is possible when there is co-infection – when a host cell is infected by more than one strain of the virus. “When copying the viral RNA, the polymerase can jump from one RNA template to another that is nearby,” says Tripathi. If the nearby sequence is that of another strain, then the new copy will be a recombinant or a hybrid of the two parental strains. Tripathi says that there are currently more than 35 recombinants of SARS-CoV-2. For example, one of the more efficient variants, XBB, which emerged in 2022, was born from recombination between two other versions of Omicron, he explains.

There are two possible reasons for the increase in these recombination events, according to the study. First, the number of infections and co-infections were high during the 2022 Omicron wave. Second, the team noticed that a specific mutation has appeared in a viral gene for an exonuclease, a protein that can cleave RNA and is believed to be involved in recombination. Tripathi explains, “Our findings show that the virus is not cooling down but is actually warming up as far as mutations go.”

Because enhanced recombination can increase the chances of new strains emerging, tracking such recombinations through regular sequencing of the virus is crucial, the researchers say.

REFERENCE: 
Shiraz R, Tripathi S, Enhanced recombination among omicron subvariants of SARS-CoV-2 contributes to viral immune escape, Journal of Medical Virology (2023). 

https://onlinelibrary.wiley.com/doi/10.1002/jmv.28519

CONTACT: 
Shashank Tripathi
Assistant Professor
Department of Microbiology & Cell Biology and Centre for Infectious Diseases Research
Indian Institute of Science (IISc)
Phone: +91 8022932884
Email: shashankt@iisc.ac.in
Website: https://cidr.iisc.ac.in/shashank/
NOTE TO JOURNALISTS: 

1. a) If any of the text in this release is reproduced verbatim, please credit the IISc press release.
2. b) For any queries about IISc press releases, please write to news@iisc.ac.inor pro@ac.in.

22 March 2023 

Power Finance Corporation Limited (PFC) has made a generous commitment to support the establishment of a state-of-the-art building that will house the Interdisciplinary Centre for Energy Research (ICER) at the Indian Institute of Science (IISc). An MoA between PFC and IISc was signed on 21 March 2023 in the presence of Mr Ravinder Singh Dhillon, CMD, PFC, and Prof Govindan Rangarajan, Director, IISc, along with other representatives from PFC and IISc.

The support from PFC comes at an opportune time when countries across the globe are focusing on net zero technologies to mitigate the environmental impact of conventional energy generation. The state-of-the-art building for ICER will foster cutting-edge fundamental and applied research on various energy-related areas, with special focus on green hydrogen generation. It will be constructed at a cost of Rs 60 crore over the next two years. The building will house modern labs, seminar rooms, classrooms and faculty rooms, as well as facilities for developing energy-related products and prototypes. It will also support PhD and Master’s programmes, and foster several collaborative programmes with academic and industry partners.

The Interdisciplinary Centre for Energy Research (ICER), among the newest research centres at IISc, was conceived in 2012 as a part of the Institute’s post-centenary vision to pursue socially relevant research in line with the Government of India’s national missions. It has since made significant contributions in several areas. For example, its ongoing research on generating green hydrogen from biomass has reached the stage of real-world demonstration in fuel cell buses. It has also established India’s first closed-loop supercritical carbon dioxide-based Brayton cycle power block. ICER has collaborations with several organisations and industries within India and abroad.

“We are extremely grateful to Power Finance Corporation Limited for generously funding a new building for the Interdisciplinary Centre for Energy Research,” said Prof Rangarajan. “Over the past decade, the Centre has made great strides in energy research and pioneered several indigenous technologies. With climate change accelerating at an alarming pace, it is imperative for academia and industry to join hands and develop novel solutions that can help us achieve net zero emissions.”

The new building will significantly accelerate advanced research in indigenous green hydrogen and net zero technologies, and increase capacity building through training and degree programmes.

CONTACT: 
IISc Office of Communications | news@iisc.ac.in

24 March 2023

– Prarthana Ghosh Dastidar

Researchers at the Indian Institute of Science (IISc) are working on designing antennas that can empower 6G technology, which is instrumental in realising efficient V2X (Vehicle to Everything) communications.

In a recent study, the team, led by Debdeep Sarkar, Assistant Professor at the Department of Electrical Communication Engineering, shows how self-interference in full-duplex communication antennas can be reduced, and consequently the movement of signals across the communication network can be faster and more bandwidth-efficient. Such full-duplex antennas are particularly helpful for applications that require almost instantaneous relay of commands, like driverless cars.

Simplified architecture of intelligent transportation system (ITS) showing V2X Connectivity (Credit: Jogesh Chandra Dash and Debdeep Sarkar)

Full-duplex antennas consist of a transmitter and a receiver to send and receive radio signals. Traditional radio transceivers are half duplex, which means that they either use signals of different frequencies for sending and receiving or there is a time lag between the signal transmitted and the signal received. This time lag is needed to ensure that there is no interference – the signals going back and forth should not cross paths with each other, similar to two people talking to each other at the same time, without pausing to listen to the other. But this also compromises the efficiency and speed of signal transfer.

In order to transmit data much faster and more efficiently, full-duplex systems are required, where both the transmitter and receiver can operate signals of the same frequency simultaneously. For such systems, eliminating self-interference is key. This is what Sarkar and his IoE-IISc postdoctoral fellow, Jogesh Chandra Dash, have been working on for the past few years.

“The broad objective of the research is that we want to eliminate the signal that is coming as self-interference,” says Sarkar. There are two ways to cancel self-interference – passive and active. Passive cancellation is done without any additional instrument, by just designing the circuit in a certain way (for example, increasing the distance between the two antennas). Active cancellation relies on additional components like signal processing units to cancel out the self-interference. But the components needed for these steps can make the antenna bulky and expensive. What is needed, instead, is a compact, cost-efficient antenna which can be easily integrated into the rest of the circuitry of any device.

The antenna developed by Sarkar and Dash, by virtue of its design, relies on passive interference, allowing it to operate as a full-duplex system. It consists of two ports, either of which can act as transmitter or receiver. The two ports are isolated from each other by electromagnetic tools called metallic vias. Metallic vias are holes drilled into the metal surface of the antenna which disrupt the electric field. In this way, the team managed to cancel out most of the interference passively, alongside achieving a cost-effective and compact design.

“We are eliminating all the conventional techniques for self-interference cancellation, and we are integrating a very simple structure that can be installed in a car,” says Dash.

In the immediate future, the team plans to optimise their device so that it can entirely remove passive interference, and reduce the overall size of the antenna. Then, it can easily be fixed onto a vehicle where it can transmit and receive data at very high speeds, bringing driverless operation as well as 6G mobile connectivity closer to reality.

REFERENCES:

Dash JC, Sarkar D, A Co-Linearly Polarized Shared Radiator Based Full-Duplex Antenna with High Tx-Rx Isolation using Vias and Stub Loaded Resonator, IEEE Transactions on Circuits and Systems-II: Express Briefs (2023)
https://ieeexplore.ieee.org/document/10024384

Dash JC, Sarkar D, A Co-Linearly Polarized Full-Duplex Antenna with Extremely High Tx-Rx Isolation, IEEE Antennas and Wireless Propagation Letters (2022)
https://ieeexplore.ieee.org/document/9841615

Dash JC, Sarkar D, Microstrip Patch Antenna System with Enhanced Inter-Port Isolation for Full-duplex/MIMO Applications, IEEE Access (2021)
https://ieeexplore.ieee.org/document/9618907

CONTACT:
Debdeep Sarkar
Assistant Professor
Department of Electrical Communication Engineering
Indian Institute of Science (IISc)
Email: debdeep@iisc.ac.in
Phone: +91-8022933158
Website: https://ece.iisc.ac.in/~debdeeps/

Jogesh Chandra Dash
IoE-IISc Postdoctoral Fellow
Department of Electrical Communication Engineering
Indian Institute of Science (IISc)
Email: jogeshdash@iisc.ac.in

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04 April 2023

Indian Institute of Science (IISc), Gitam University, and Water Technology Centre – Water & Effluent Treatment (WET IC) Division of L&T have signed a Memorandum of Understanding (MoU) to advance research and development in areas relevant to India’s needs.

The MoU signing ceremony was held on 24 March 2023, at the IISc campus in Bengaluru. The agreement was signed in the presence of Prof G Rangarajan, Director of IISc, by Capt Sridhar Warrier, Registrar at IISc, Prof MS Mohan Kumar, Pro Vice-Chancellor of Gitam University, and Mr S Jagannathan, Vice President & Chief Technology Officer, Water & Effluent Treatment Division of L&T.

Under the MoU, the three organisations will collaborate in areas such as water and wastewater transport & treatment, hydrology, AI and ML interventions in water and wastewater treatment, and environmental protection. The partnership will focus on developing innovative and sustainable solutions to address India’s challenges in these critical areas.

Speaking on the occasion, Prof Rangarajan said, “IISc is pleased to collaborate with Gitam University and L&T’s Water Technology Centre, WET IC, to advance India-relevant R&D. This partnership will enable us to leverage our collective expertise and resources to develop cutting-edge solutions that can address pressing challenges facing our country.”

Prof MS Mohan Kumar, Pro Vice-Chancellor of GITAM University, said, “We are excited to partner with IISc and L&T’s Water Technology Centre, WET IC, in this important national initiative. This MoU will enable us to work together to create impactful solutions that address the challenges facing India and contribute to the country’s development.”

Mr S Jagannathan of L&T said, “We are delighted to collaborate with IISc and GITAM University in this most important area of water. Our partnership will enable us to develop innovative, scalable and sustainable solutions that address India’s challenges in water and wastewater transport & treatment, smart water management, energy-neutral treatment plants, implementation of digital solutions in the water domain and environmental protection at large.”

This MoU signing marks a significant milestone in advancing India-relevant R&D in water-related areas through collaboration between academia and industry.

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