The Indian Institute of Technology Kanpur (IITK) has unveiled the world’s first Brain-Computer Interface (BCI)-based Robotic Hand Exoskeleton, a groundbreaking innovation set to revolutionize stroke rehabilitation. This technology promises to accelerate recovery and improve patient outcomes by redefining post-stroke therapy. Developed over 15 years of rigorous research led by Prof. Ashish Dutta from IIT Kanpur’s Department of Mechanical Engineering, the project was supported by India’s Department of Science and Technology (DST), UK India Education and Research Initiative (UKIERI), and the Indian Council of Medical Research (ICMR).

The BCI-based robotic hand exoskeleton utilizes a unique closed-loop control system to actively engage the patient’s brain during therapy. It integrates three key components: a Brain-Computer Interface that captures EEG signals from the motor cortex to detect the patient’s intent to move, a robotic hand exoskeleton that assists with therapeutic hand movements, and software that synchronizes brain signals with the exoskeleton for real-time feedback. This coordination helps foster continuous brain engagement, leading to faster and more effective recovery.

“Stroke recovery is a long and often uncertain process. Our device bridges the gap between physical therapy, brain engagement, and visual feedback creating a closed-loop control system that activates brain plasticity, which is the brain’s ability to change its structure and function in response to stimuli,” said Prof. Ashish Dutta. “This is especially significant for patients whose recovery has plateaued, as it offers renewed hope for further improvement and regaining mobility. With promising results in both India and the UK, we are optimistic that this device will make a significant impact in the field of neurorehabilitation.”

Traditional stroke recovery often faces challenges, especially when motor impairments stem from damage to the motor cortex. Conventional physiotherapy methods may fall short due to limited brain involvement. The new device addresses this gap by linking brain activity with physical movement. During therapy, patients are guided on-screen to perform hand movements, such as opening or closing their fist, while EEG signals from the brain and EMG signals from the muscles are used to activate the robotic exoskeleton in an assist-as-required mode. This synchronization ensures the brain, muscles, and visual engagement work together, improving recovery outcomes.

Pilot clinical trials, conducted in collaboration with Regency Hospital in India and the University of Ulster in the UK, have yielded impressive results. Remarkably, eight patients—four in India and four in the UK—who had reached a recovery plateau one or two years post-stroke achieved full recovery through the BCI-based robotic therapy. The device’s active engagement of the brain during therapy has proven to lead to faster and more comprehensive recovery compared to traditional physiotherapy.

While stroke recovery is typically most effective within the first six to twelve months, this innovative device has demonstrated its ability to facilitate recovery even beyond this critical period. With large-scale clinical trials underway at Apollo Hospitals in India, the device is expected to be commercially available within three to five years, offering new hope for stroke patients worldwide.

Aluminum, the second-most-produced metal in the world after steel, is a crucial material in industries ranging from packaging to electronics and aerospace. With global demand projected to rise by 40 percent by the end of the decade, aluminum production is set to significantly increase, bringing with it heightened environmental concerns. A new breakthrough from MIT engineers aims to tackle one of the major challenges of aluminum production—waste.

The research team at the Massachusetts Institute of Technology (MIT) has developed a novel nanofiltration membrane that could drastically reduce the hazardous waste generated during aluminum manufacturing. This membrane could potentially help aluminum plants recycle aluminum ions that would otherwise be lost in waste streams, enabling upcycling and reducing environmental impacts.

“Our membrane technology not only cuts down on hazardous waste but also enables a circular economy for aluminum by reducing the need for new mining,” said John Lienhard, the Abdul Latif Jameel Professor of Water in MIT’s Department of Mechanical Engineering, according to a press release issued by MIT. He is also the director of the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS). “This offers a promising solution to address environmental concerns while meeting the growing demand for aluminum.”

In a study published this week in ACS Sustainable Chemistry and Engineering, Lienhard and his colleagues demonstrated the membrane’s effectiveness in laboratory experiments. They found that the membrane was able to capture more than 99 percent of aluminum ions from solutions that closely mimicked the waste streams produced by aluminum plants.

If scaled up, this technology could reduce the amount of wasted aluminum and improve the overall environmental quality of the waste produced by these plants.

The Aluminum Production Problem

Aluminum production starts with the mining of bauxite, an ore rich in aluminum. The bauxite undergoes chemical processing to separate aluminum oxide (alumina) from other impurities. This alumina is then transported to refineries, where it is placed in electrolysis vats containing molten cryolite. Through electrolysis, alumina breaks down, and pure aluminum is separated out.

However, over time, the cryolite electrolyte accumulates impurities, including sodium, lithium, and potassium ions, which reduce its effectiveness in the process. When these impurities reach critical levels, the cryolite must be replaced, creating a hazardous sludge that contains residual aluminum and other pollutants. The amount of aluminum lost in this waste can be substantial.

“We learned that for a traditional aluminum plant, something like 2,800 tons of aluminum are wasted per year,” said Trent Lee, lead author of the study and an MIT mechanical engineering undergraduate. “We were looking at ways that the industry can be more efficient, and we found cryolite waste hadn’t been well-researched in terms of recycling some of its waste products.”

A Membrane for Efficiency

In their new work, Lienhard’s team developed a membrane capable of selectively filtering aluminum from cryolite waste. The goal was to recover aluminum ions while allowing other less problematic ions, such as sodium, to pass through. The captured aluminum could then be reused in the electrolysis process, reducing the need for new materials and increasing overall efficiency.

The new membrane technology is based on a design used in conventional water treatment plants. These membranes, made from polymer materials, are perforated with tiny pores that selectively allow certain ions and molecules to pass through. In collaboration with the Japanese membrane company Nitto Denko, the MIT team adapted this technology to capture aluminum ions specifically.

The aluminum ions in cryolite waste carry a higher positive charge than sodium and other cations, which makes them easier to isolate. By applying a thin, positively charged coating to the membrane, the researchers were able to create a barrier that repels aluminum ions while allowing the other, less positively charged ions to flow through.

“We found that the membrane consistently captured 99.5 percent of aluminum ions while allowing sodium and other cations to pass,” explained Zi Hao Foo, a postdoctoral researcher at the University of California, Berkeley, and co-author of the study. “We also tested the membrane in solutions of varying pH levels, and it maintained its performance, even in highly acidic conditions.”

Scaling Up for Industry

The team’s experimental membrane is about the size of a playing card, but to treat cryolite waste in an industrial-scale aluminum production plant, they envision a scaled-up version similar to those used in desalination plants. In these plants, long sheets of membrane are rolled into spirals, allowing water to flow through them efficiently.

“This paper shows the viability of membranes for innovations in circular economies,” said Lee. “This membrane provides the dual benefit of upcycling aluminum while reducing hazardous waste.”

By applying this membrane technology, the aluminum industry could significantly cut down on waste and reduce its environmental footprint, all while improving efficiency and meeting the rising global demand for aluminum.

Looking Ahead

With their breakthrough in nanofiltration technology, MIT engineers have opened the door to a more sustainable and circular approach to aluminum production. By reclaiming valuable aluminum from waste streams, they are not only advancing the efficiency of aluminum manufacturing but also helping to address the environmental challenges posed by an industry poised for rapid growth in the coming years

A new study led by the University of Cambridge offers fresh insights into how urban tree canopies, while effective at cooling cities during the day, may inadvertently trap heat at night.

As global temperatures continue to rise, many cities are grappling with the effects of urban heat stress, which is linked to increased illness, energy consumption, and social inequality. Excessive heat can also damage urban infrastructure, highlighting the urgent need for effective mitigation strategies. Among these, tree planting has become a central component of efforts to cool down cities.

However, a recent study led by the University of Cambridge warns that not all tree species or planting methods are equally effective in reducing urban temperatures. According to Dr. Ronita Bardhan, Associate Professor of Sustainable Built Environment at the University of Cambridge’s Department of Architecture, “Trees have a crucial role to play in cooling cities down but we need to plant them much more strategically to maximize the benefits they can provide.”

New Insights on Tree Cooling and Heating Effects

Published in Communications Earth & Environment, the study offers the first comprehensive global assessment of urban tree cooling. By analyzing 182 studies from 110 cities worldwide, the research reveals how tree planting can lower pedestrian-level air temperatures by up to 12°C, with 83% of cities studied achieving temperatures below the “thermal comfort threshold” of 26°C. However, the study also shows that the cooling effects of trees can vary dramatically depending on species, climate, and urban design.

Dr. Bardhan noted, “Our study busts the myth that trees are the ultimate panacea for overheating cities across the globe. The cooling effects of trees are complex and vary significantly depending on the context in which they are planted.”

Cooling Benefits Vary by Climate Type

The study found that urban trees tend to be more effective in cooling cities in hot, dry climates compared to those in humid, tropical areas. In hot and dry climates like Nigeria’s savanna, trees can lower city temperatures by as much as 12°C during the day, but can also increase nighttime temperatures by up to 0.8°C. In arid climates, trees were shown to cool cities by just over 9°C but also raise nighttime temperatures by 0.4°C. Conversely, in tropical rainforest climates, daytime cooling was limited to about 2°C, with nighttime warming reaching 0.8°C.

“Trees perform best in dry, hot climates, but in tropical regions with high humidity, their nighttime warming effect can negate their daytime cooling benefits,” said Dr. Bardhan.

Strategic Tree Planting: The Key to Maximizing Cooling

The study underscores the importance of planting trees in a way that aligns with a city’s specific urban form and climate conditions. Cities with open layouts, for instance, benefit from a mix of evergreen and deciduous trees of varying sizes, leading to more effective cooling across different seasons. In contrast, compact urban layouts, like those in Cairo or Dubai, favor evergreen species that are better suited to dry, hot conditions.

The researchers found that mixed-species planting could provide up to 0.5°C more cooling than monoculture tree planting, as different trees offer varying levels of shade and sunlight penetration at different heights. Furthermore, larger green spaces allow for bigger tree canopies, leading to better overall cooling in dry climates.

“Our study provides context-specific greening guidelines for urban planners to more effectively harness tree cooling in the face of global warming,” Dr. Bardhan said. “Urban planners need to plant the right mix of trees in optimal positions to maximize cooling benefits.”

Looking to the Future: Planning for Warmer Climates

The study also stresses that as climate change progresses, it is essential for cities to choose resilient tree species that will continue to thrive under hotter conditions. “Urban planners should plan for future warmer climates by choosing resilient species which will continue to thrive and maintain cooling benefits,” Dr. Bardhan emphasized.

Furthermore, the researchers note that trees alone cannot solve the issue of urban heat. To complement tree planting, solutions like solar shading and reflective materials should continue to play a vital role in mitigating the heat effects in cities.

A Tool for Urban Planners

In an effort to make these findings more accessible, the researchers have developed an interactive database and map that allows users to estimate the cooling efficacy of different tree planting strategies based on the climate and urban characteristics of cities worldwide. This tool will help urban planners design more effective, climate-specific tree planting schemes.