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      in Security

      Scientists uncover the amazing way sandgrouse hold water in their feathers

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      Many birds’ feathers are remarkably efficient at shedding water — so much so that “like water off a duck’s back” is a common expression. Much more unusual are the belly feathers of the sandgrouse, especially Namaqua sandgrouse, which absorb and retain water so efficiently the male birds can fly more than 20 kilometers from a distant watering hole back to the nest and still retain enough water in their feathers for the chicks to drink and sustain themselves in the searing deserts of Namibia, Botswana, and South Africa.

      How do those feathers work? While scientists had inferred a rough picture, it took the latest tools of microscopy, and patient work with a collection of sandgrouse feathers, to unlock the unique structural details that enable the feathers to hold water. The findings appear today in the Journal of the Royal Society Interface, in a paper by Lorna Gibson, the Matoula S. Salapatas Professor of Materials Science and Engineering and a professor of mechanical engineering at MIT, and Professor Jochen Mueller of Johns Hopkins University.

      The unique water-carrying ability of sandgrouse feathers was first reported back in 1896, Gibson says, by E.G.B. Meade-Waldo, who was breeding the birds in captivity. “He saw them behaving like this, and nobody believed him! I mean, it just sounded so outlandish,” Gibson says.

      In 1967, Tom Cade and Gordon MacLean reported detailed observations of the birds at watering holes, in a study that proved the unique behavior was indeed real. The scientists found that male sandgrouse feathers could hold about 25 milliliters of water, or about a tenth of a cup, after the bird had spent about five minutes dipping in the water and fluffing its feathers.

      About half of that amount can evaporate during the male bird’s half-hour-long flight back to the nest, where the chicks, which cannot fly for about their first month, drink the remainder straight from the feathers.

      Cade and MacLean “had part of the story,” Gibson says, but the tools didn’t exist at the time to carry out the detailed imaging of the feather structures that the new study was able to do.

      Gibson and Mueller carried out their study using scanning electron microscopy, micro-computed tomography, and video imaging. They borrowed Namaqua sandgrouse belly feathers from Harvard University’s Museum of Comparative Zoology, which has a collection of specimens of about 80 percent of the world’s birds.

      Bird feathers in general have a central shaft, from which smaller barbs extend, and then smaller barbules extend out from those. Sandgrouse feathers are structured differently, however. In the inner zone of the feather, the barbules have a helically coiled structure close to their base and then a straight extension. In the outer zone of the feather, the barbules lack the helical coil and are simply straight. Both parts lack the grooves and hooks that hold the vane of contour feathers together in most other birds.
      Video of water spreading through the specialized sandgrouse feathers, under magnification, shows the uncoiling and spreading of the feather’s barbules as they become wet. Initially, most barbules in the outer zone of the feather form tubular features.Credit: Specimen #142928, Museum of Comparative Zoology, Harvard University © President and Fellows of Harvard College.

      When wetted, the coiled portions of the barbules unwind and rotate to be perpendicular to the vane, producing a dense forest of fibers that can hold water through capillary action. At the same time, the barbules in the outer zone curl inward, helping to hold the water in.

      The microscopy techniques used in the new study allowed the dimensions of the different parts of the feather to be measured. In the inner zone, the barb shafts are large and stiff enough to provide a rigid base about which the other parts of the feather deform, and the barbules are small and flexible enough that surface tension is sufficient to bend the straight extensions into tear-like structures that hold water. And in the outer zone, the barb shafts and barbules are smaller still, allowing them to curl around the inner zone, further retaining water.

      While previous work had suggested that surface tension produced the water retention characteristics, “what we did was make measurements of the dimensions and do some calculations to show that that’s what is actually happening,” Gibson says. Her group’s work demonstrated that the varying stiffnesses of the different feather parts plays a key role in their ability to hold water.

      The study was mostly driven by intellectual curiosity about this unique behavioral phenomenon, Gibson says. “We just wanted to see how it works. The whole story just seemed so interesting.” But she says it might lead to some useful applications. For example, in desert regions where water is scarce but fog and dew regularly occur, such as in Chile’s Atacama Desert, some adaptation of this feather structure might be incorporated into the systems of huge nets that are used to collect water. “You could imagine this could be a way to improve those systems,” she says. “A material with this kind of structure might be more effective at fog harvesting and holding the water.”

      “This fascinating and in-depth study reveals how the different parts of the sandgrouse’s belly feathers — including the microscopic barb shafts and barbules — work together to hold water,” says Mary Caswell Stoddard, an evolutionary biologist at Princeton University, who was not associated with this study. “By using a suite of advanced imaging techniques to describe the belly feathers and estimate their bending stiffnesses, Mueller and Gibson add rich new details to our understanding of the sandgrouse’s water-carrying feathers. … This study may inspire others to take a closer look at diverse feather microstructures across bird species — and to wonder whether these structures, as in sandgrouse, help support unusual or surprising functions.”

      The work was partly supported by the National Science Foundation and the Matoula S. Salapatas Professorship in Materials Science and Engineering at MIT. More

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      in Environment

      Detailed images from space offer clearer picture of drought effects on plants

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      “MIT is a place where dreams come true,” says César Terrer, an assistant professor in the Department of Civil and Environmental Engineering. Here at MIT, Terrer says he’s given the resources needed to explore ideas he finds most exciting, and at the top of his list is climate science. In particular, he is interested in plant-soil interactions, and how the two can mitigate impacts of climate change. In 2022, Terrer received seed grant funding from the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) to produce drought monitoring systems for farmers. The project is leveraging a new generation of remote sensing devices to provide high-resolution plant water stress at regional to global scales.

      Growing up in Granada, Spain, Terrer always had an aptitude and passion for science. He studied environmental science at the University of Murcia, where he interned in the Department of Ecology. Using computational analysis tools, he worked on modeling species distribution in response to human development. Early on in his undergraduate experience, Terrer says he regarded his professors as “superheroes” with a kind of scholarly prowess. He knew he wanted to follow in their footsteps by one day working as a faculty member in academia. Of course, there would be many steps along the way before achieving that dream. 

      Upon completing his undergraduate studies, Terrer set his sights on exciting and adventurous research roles. He thought perhaps he would conduct field work in the Amazon, engaging with native communities. But when the opportunity arose to work in Australia on a state-of-the-art climate change experiment that simulates future levels of carbon dioxide, he headed south to study how plants react to CO2 in a biome of native Australian eucalyptus trees. It was during this experience that Terrer started to take a keen interest in the carbon cycle and the capacity of ecosystems to buffer rising levels of CO2 caused by human activity.

      Around 2014, he began to delve deeper into the carbon cycle as he began his doctoral studies at Imperial College London. The primary question Terrer sought to answer during his PhD was “will plants be able to absorb predicted future levels of CO2 in the atmosphere?” To answer the question, Terrer became an early adopter of artificial intelligence, machine learning, and remote sensing to analyze data from real-life, global climate change experiments. His findings from these “ground truth” values and observations resulted in a paper in the journal Science. In it, he claimed that climate models most likely overestimated how much carbon plants will be able to absorb by the end of the century, by a factor of three. 

      After postdoctoral positions at Stanford University and the Universitat Autonoma de Barcelona, followed by a prestigious Lawrence Fellowship, Terrer says he had “too many ideas and not enough time to accomplish all those ideas.” He knew it was time to lead his own group. Not long after applying for faculty positions, he landed at MIT. 

      New ways to monitor drought

      Terrer is employing similar methods to those he used during his PhD to analyze data from all over the world for his J-WAFS project. He and postdoc Wenzhe Jiao collect data from remote sensing satellites and field experiments and use machine learning to come up with new ways to monitor drought. Terrer says Jiao is a “remote sensing wizard,” who fuses data from different satellite products to understand the water cycle. With Jiao’s hydrology expertise and Terrer’s knowledge of plants, soil, and the carbon cycle, the duo is a formidable team to tackle this project.

      According to the U.N. World Meteorological Organization, the number and duration of droughts has increased by 29 percent since 2000, as compared to the two previous decades. From the Horn of Africa to the Western United States, drought is devastating vegetation and severely stressing water supplies, compromising food production and spiking food insecurity. Drought monitoring can offer fundamental information on drought location, frequency, and severity, but assessing the impact of drought on vegetation is extremely challenging. This is because plants’ sensitivity to water deficits varies across species and ecosystems. 

      Terrer and Jiao are able to obtain a clearer picture of how drought is affecting plants by employing the latest generation of remote sensing observations, which offer images of the planet with incredible spatial and temporal resolution. Satellite products such as Sentinel, Landsat, and Planet can provide daily images from space with such high resolution that individual trees can be discerned. Along with the images and datasets from satellites, the team is using ground-based observations from meteorological data. They are also using the MIT SuperCloud at MIT Lincoln Laboratory to process and analyze all of the data sets. The J-WAFS project is among one of the first to leverage high-resolution data to quantitatively measure plant drought impacts in the United States with the hopes of expanding to a global assessment in the future.

      Assisting farmers and resource managers 

      Every week, the U.S. Drought Monitor provides a map of drought conditions in the United States. The map has zero resolution and is more of a drought recap or summary, unable to predict future drought scenarios. The lack of a comprehensive spatiotemporal evaluation of historic and future drought impacts on global vegetation productivity is detrimental to farmers both in the United States and worldwide.  

      Terrer and Jiao plan to generate metrics for plant water stress at an unprecedented resolution of 10-30 meters. This means that they will be able to provide drought monitoring maps at the scale of a typical U.S. farm, giving farmers more precise, useful data every one to two days. The team will use the information from the satellites to monitor plant growth and soil moisture, as well as the time lag of plant growth response to soil moisture. In this way, Terrer and Jiao say they will eventually be able to create a kind of “plant water stress forecast” that may be able to predict adverse impacts of drought four weeks in advance. “According to the current soil moisture and lagged response time, we hope to predict plant water stress in the future,” says Jiao. 

      The expected outcomes of this project will give farmers, land and water resource managers, and decision-makers more accurate data at the farm-specific level, allowing for better drought preparation, mitigation, and adaptation. “We expect to make our data open-access online, after we finish the project, so that farmers and other stakeholders can use the maps as tools,” says Jiao. 

      Terrer adds that the project “has the potential to help us better understand the future states of climate systems, and also identify the regional hot spots more likely to experience water crises at the national, state, local, and tribal government scales.” He also expects the project will enhance our understanding of global carbon-water-energy cycle responses to drought, with applications in determining climate change impacts on natural ecosystems as a whole. More

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      in Energy

      How to pull carbon dioxide out of seawater

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      As carbon dioxide continues to build up in the Earth’s atmosphere, research teams around the world have spent years seeking ways to remove the gas efficiently from the air. Meanwhile, the world’s number one “sink” for carbon dioxide from the atmosphere is the ocean, which soaks up some 30 to 40 percent of all of the gas produced by human activities.

      Recently, the possibility of removing carbon dioxide directly from ocean water has emerged as another promising possibility for mitigating CO2 emissions, one that could potentially someday even lead to overall net negative emissions. But, like air capture systems, the idea has not yet led to any widespread use, though there are a few companies attempting to enter this area.

      Now, a team of researchers at MIT says they may have found the key to a truly efficient and inexpensive removal mechanism. The findings were reported this week in the journal Energy and Environmental Science, in a paper by MIT professors T. Alan Hatton and Kripa Varanasi, postdoc Seoni Kim, and graduate students Michael Nitzsche, Simon Rufer, and Jack Lake.

      The existing methods for removing carbon dioxide from seawater apply a voltage across a stack of membranes to acidify a feed stream by water splitting. This converts bicarbonates in the water to molecules of CO2, which can then be removed under vacuum. Hatton, who is the Ralph Landau Professor of Chemical Engineering, notes that the membranes are expensive, and chemicals are required to drive the overall electrode reactions at either end of the stack, adding further to the expense and complexity of the processes. “We wanted to avoid the need for introducing chemicals to the anode and cathode half cells and to avoid the use of membranes if at all possible” he says.

      The team came up with a reversible process consisting of membrane-free electrochemical cells. Reactive electrodes are used to release protons to the seawater fed to the cells, driving the release of the dissolved carbon dioxide from the water. The process is cyclic: It first acidifies the water to convert dissolved inorganic bicarbonates to molecular carbon dioxide, which is collected as a gas under vacuum. Then, the water is fed to a second set of cells with a reversed voltage, to recover the protons and turn the acidic water back to alkaline before releasing it back to the sea. Periodically, the roles of the two cells are reversed once one set of electrodes is depleted of protons (during acidification) and the other has been regenerated during alkalization.

      This removal of carbon dioxide and reinjection of alkaline water could slowly start to reverse, at least locally, the acidification of the oceans that has been caused by carbon dioxide buildup, which in turn has threatened coral reefs and shellfish, says Varanasi, a professor of mechanical engineering. The reinjection of alkaline water could be done through dispersed outlets or far offshore to avoid a local spike of alkalinity that could disrupt ecosystems, they say.

      “We’re not going to be able to treat the entire planet’s emissions,” Varanasi says. But the reinjection might be done in some cases in places such as fish farms, which tend to acidify the water, so this could be a way of helping to counter that effect.

      Once the carbon dioxide is removed from the water, it still needs to be disposed of, as with other carbon removal processes. For example, it can be buried in deep geologic formations under the sea floor, or it can be chemically converted into a compound like ethanol, which can be used as a transportation fuel, or into other specialty chemicals. “You can certainly consider using the captured CO2 as a feedstock for chemicals or materials production, but you’re not going to be able to use all of it as a feedstock,” says Hatton. “You’ll run out of markets for all the products you produce, so no matter what, a significant amount of the captured CO2 will need to be buried underground.”

      Initially at least, the idea would be to couple such systems with existing or planned infrastructure that already processes seawater, such as desalination plants. “This system is scalable so that we could integrate it potentially into existing processes that are already processing ocean water or in contact with ocean water,” Varanasi says. There, the carbon dioxide removal could be a simple add-on to existing processes, which already return vast amounts of water to the sea, and it would not require consumables like chemical additives or membranes.

      “With desalination plants, you’re already pumping all the water, so why not co-locate there?” Varanasi says. “A bunch of capital costs associated with the way you move the water, and the permitting, all that could already be taken care of.”

      The system could also be implemented by ships that would process water as they travel, in order to help mitigate the significant contribution of ship traffic to overall emissions. There are already international mandates to lower shipping’s emissions, and “this could help shipping companies offset some of their emissions, and turn ships into ocean scrubbers,” Varanasi says.

      The system could also be implemented at locations such as offshore drilling platforms, or at aquaculture farms. Eventually, it could lead to a deployment of free-standing carbon removal plants distributed globally.

      The process could be more efficient than air-capture systems, Hatton says, because the concentration of carbon dioxide in seawater is more than 100 times greater than it is in air. In direct air-capture systems it is first necessary to capture and concentrate the gas before recovering it. “The oceans are large carbon sinks, however, so the capture step has already kind of been done for you,” he says. “There’s no capture step, only release.” That means the volumes of material that need to be handled are much smaller, potentially simplifying the whole process and reducing the footprint requirements.

      The research is continuing, with one goal being to find an alternative to the present step that requires a vacuum to remove the separated carbon dioxide from the water. Another need is to identify operating strategies to prevent precipitation of minerals that can foul the electrodes in the alkalinization cell, an inherent issue that reduces the overall efficiency in all reported approaches. Hatton notes that significant progress has been made on these issues, but that it is still too early to report on them. The team expects that the system could be ready for a practical demonstration project within about two years.

      “The carbon dioxide problem is the defining problem of our life, of our existence,” Varanasi says. “So clearly, we need all the help we can get.”

      The work was supported by ARPA-E. More

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      in Environment

      Moving water and earth

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      As a river cuts through a landscape, it can operate like a conveyer belt, moving truckloads of sediment over time. Knowing how quickly or slowly this sediment flows can help engineers plan for the downstream impact of restoring a river or removing a dam. But the models currently used to estimate sediment flow can be off by a wide margin.

      An MIT team has come up with a better formula to calculate how much sediment a fluid can push across a granular bed — a process known as bed load transport. The key to the new formula comes down to the shape of the sediment grains.

      It may seem intuitive: A smooth, round stone should skip across a river bed faster than an angular pebble. But flowing water also pushes harder on the angular pebble, which could erase the round stone’s advantage. Which effect wins? Existing sediment transport models surprisingly don’t offer an answer, mainly because the problem of measuring grain shape is too unwieldy: How do you quantify a pebble’s contours?

      The MIT researchers found that instead of considering a grain’s exact shape, they could boil the concept of shape down to two related properties: friction and drag. A grain’s drag, or resistance to fluid flow, relative to its internal friction, the resistance to sliding past other grains, can provide an easy way to gauge the effects of a grain’s shape.

      When they incorporated this new mathematical measure of grain shape into a standard model for bed load transport, the new formula made predictions that matched experiments that the team performed in the lab.

      “Sediment transport is a part of life on Earth’s surface, from the impact of storms on beaches to the gravel nests in mountain streams where salmon lay their eggs,” the team writes of their new study, appearing today in Nature. “Damming and sea level rise have already impacted many such terrains and pose ongoing threats. A good understanding of bed load transport is crucial to our ability to maintain these landscapes or restore them to their natural states.”

      The study’s authors are Eric Deal, Santiago Benavides, Qiong Zhang, Ken Kamrin, and Taylor Perron of MIT, and Jeremy Venditti and Ryan Bradley of Simon Fraser University in Canada.

      Figuring flow

      Video of glass spheres (top) and natural river gravel (bottom) undergoing bed load transport in a laboratory flume, slowed down 17x relative to real time. Average grain diameter is about 5 mm. This video shows how rolling and tumbling natural grains interact with one another in a way that is not possible for spheres. What can’t be seen so easily is that natural grains also experience higher drag forces from the flowing water than spheres do.

      Credit: Courtesy of the researchers

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      Bed load transport is the process by which a fluid such as air or water drags grains across a bed of sediment, causing the grains to hop, skip, and roll along the surface as a fluid flows through. This movement of sediment in a current is what drives rocks to migrate down a river and sand grains to skip across a desert.

      Being able to estimate bed load transport can help scientists prepare for situations such as urban flooding and coastal erosion. Since the 1930s, one formula has been the go-to model for calculating bed load transport; it’s based on a quantity known as the Shields parameter, after the American engineer who originally derived it. This formula sets a relationship between the force of a fluid pushing on a bed of sediment, and how fast the sediment moves in response. Albert Shields incorporated certain variables into this formula, including the average size and density of a sediment’s grains — but not their shape.

      “People may have backed away from accounting for shape because it’s one of these very scary degrees of freedom,” says Kamrin, a professor of mechanical engineering at MIT. “Shape is not a single number.”

      And yet, the existing model has been known to be off by a factor of 10 in its predictions of sediment flow. The team wondered whether grain shape could be a missing ingredient, and if so, how the nebulous property could be mathematically represented.

      “The trick was to focus on characterizing the effect that shape has on sediment transport dynamics, rather than on characterizing the shape itself,” says Deal.

      “It took some thinking to figure that out,” says Perron, a professor of geology in MIT’s Department of Earth, Atmospheric and Planetary Sciences. “But we went back to derive the Shields parameter, and when you do the math, this ratio of drag to friction falls out.”

      Drag and drop

      Their work showed that the Shields parameter — which predicts how much sediment is transported — can be modified to include not just size and density, but also grain shape, and furthermore, that a grain’s shape can be simply represented by a measure of the grain’s drag and its internal friction. The math seemed to make sense. But could the new formula predict how sediment actually flows?

      To answer this, the researchers ran a series of flume experiments, in which they pumped a current of water through an inclined tank with a floor covered in sediment. They ran tests with sediment of various grain shapes, including beds of round glass beads, smooth glass chips, rectangular prisms, and natural gravel. They measured the amount of sediment that was transported through the tank in a fixed amount of time. They then determined the effect of each sediment type’s grain shape by measuring the grains’ drag and friction.

      For drag, the researchers simply dropped individual grains down through a tank of water and gathered statistics for the time it took the grains of each sediment type to reach the bottom. For instance, a flatter grain type takes a longer time on average, and therefore has greater drag, than a round grain type of the same size and density.

      To measure friction, the team poured grains through a funnel and onto a circular tray, then measured the resulting pile’s angle, or slope — an indication of the grains’ friction, or ability to grip onto each other.

      For each sediment type, they then worked the corresponding shape’s drag and friction into the new formula, and found that it could indeed predict the bedload transport, or the amount of moving sediment that the researchers measured in their experiments.

      The team says the new model more accurately represents sediment flow. Going forward, scientists and engineers can use the model to better gauge how a river bed will respond to scenarios such as sudden flooding from severe weather or the removal of a dam.

      “If you were trying to make a prediction of how fast all that sediment will get evacuated after taking a dam out, and you’re wrong by a factor of three or five, that’s pretty bad,” Perron says. “Now we can do a lot better.”

      This research was supported, in part, by the U.S. Army Research Laboratory. More

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      in Environment

      Looking to the past to prepare for an uncertain future

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      Aviva Intveld, an MIT senior majoring in Earth, atmospheric, and planetary sciences, is accustomed to city life. But despite hailing from metropolitan Los Angeles, she has always maintained a love for the outdoors.

      “Growing up in L.A., you just have a wealth of resources when it comes to beautiful environments,” she says, “but you’re also constantly living connected to the environment.” She developed a profound respect for the natural world and its effects on people, from the earthquakes that shook the ground to the wildfires that displaced inhabitants.

      “I liked the lifestyle that environmental science afforded,” Intveld recalls. “I liked the idea that you can make a career out of spending a huge amount of time in the field and exploring different parts of the world.”

      From the moment she arrived at MIT, Intveld threw herself into research on and off campus. During her first semester, she joined Terrascope, a program that encourages first-year students to tackle complex, real-world problems. Intveld and her cohort developed proposals to make recovery from major storms in Puerto Rico faster, more sustainable, and more equitable.

      Intveld also spent a semester studying drought stress in the lab of Assistant Professor David Des Marais, worked as a research assistant at a mineral sciences research lab back in L.A., and interned at the World Wildlife Fund. Most of her work focused on contemporary issues like food insecurity and climate change. “I was really interested in questions about today,” Intveld says.

      Her focus began to shift to the past when she interned as a research assistant at the Marine Geoarchaeology and Micropaleontology Lab at the University of Haifa. For weeks, she would spend eight hours a day hunched over a microscope, using a paintbrush to sort through grains of sand from the coastal town of Caesarea. She was looking for tiny spiral-shaped fossils of foraminifera, an organism that resides in seafloor sediments.

      These microfossils can reveal a lot about the environment in which they originated, including extreme weather events. By cataloging diverse species of foraminifera, Intveld was helping to settle a rather niche debate in the field of geoarchaeology: Did tsunamis destroy the harbor of Caesarea during the time of the ancient Romans?

      But in addition to figuring out if and when these natural disasters occurred, Intveld was interested in understanding how ancient communities prepared for and recovered from them. What methods did they use? Could those same methods be used today?

      Intveld’s research at the University of Haifa was part of the Onward Israel program, which offers young Jewish people the chance to participate in internships, academic study, and fellowships in Israel. Intveld describes the experience as a great opportunity to learn about the culture, history, and diversity of the Israeli community. The trip was also an excellent lesson in dealing with challenging situations.

      Intveld suffers from claustrophobia, but she overcame her fears to climb through the Bar Kokhba caves, and despite a cat allergy, she grew to adore the many stray cats that roam the streets of Haifa. “Sometimes you can’t let your physical limitations stop you from doing what you love,” she quips.

      Over the course of her research, Intveld has often found herself in difficult and even downright dangerous situations, all of which she looks back on with good humor. As part of an internship with the National Oceanic and Atmospheric Administration, she spent three months investigating groundwater in Homer, Alaska. While she was there, she learned to avoid poisonous plants out in the field, got lost bushwhacking, and was twice charged by a moose.

      These days, Intveld spends less time in the field and more time thinking about the ancient past. She works in the lab of Associate Professor David McGee, where her undergraduate thesis research focuses on reconstructing the paleoclimate and paleoecology of northeastern Mexico during the Early Holocene. To get an idea of what the Mexican climate looked like thousands of years ago, Intveld analyzes stable isotopes and trace elements in stalagmites taken from Mexican caves. By analyzing the isotopes of carbon and oxygen present in these stalagmites, which were formed over thousands of years from countless droplets of mineral-rich rainwater, Intveld can estimate the amount of rainfall and average temperature in a given time period.

      Intveld is primarily interested in how the area’s climate may have influenced human migration. “It’s very interesting to learn about the history of human motivation, what drives us to do what we do,” she explains. “What causes humans to move, and what causes us to stay?” So far, it seems the Mexican climate during the Early Holocene was quite inconsistent, with oscillating periods of wet and dry, but Intveld needs to conduct more research before drawing any definitive conclusions.

      Recent research has linked periods of drought in the geological record to periods of violence in the archaeological one, suggesting ancient humans often fought over access to water. “I think you can easily see the connections to stuff that we deal with today,” Intveld says, pointing out the parallels between paleolithic migration and today’s climate refugees. “We have to answer a lot of difficult questions, and one way that we can do so is by looking to see what earlier human communities did and what we can learn from them.”

      Intveld recognizes the impact of the past on our present and future in many other areas. She works as a tour guide for the List Visual Arts Center, where she educates people about public art on the MIT campus. “[Art] interested me as a way to experience history and learn about the story of different communities and people over time,” she says.

      Intveld is also unafraid to acknowledge the history of discrimination and exclusion in science. “Earth science has a big problem when it comes to inclusion and diversity,” she says. As a member of the EAPS Diversity, Equity and Inclusion Committee, she aims to make earth science more accessible.

      “Aviva has a clear drive to be at the front lines of geoscience research, connecting her work to the urgent environmental issues we’re all facing,” says McGee. “She also understands the critical need for our field to include more voices, more perspectives — ultimately making for better science.”

      After MIT, Intveld hopes to pursue an advanced degree in the field of sustainable mining. This past spring, she studied abroad at Imperial College London, where she took courses within the Royal School of Mines. As Intveld explains, mining is becoming crucial to sustainable energy. The rise of electric vehicles in places like California has increased the need for energy-critical elements like lithium and cobalt, but mining for these elements often does more harm than good. “The current mining complex is very environmentally destructive,” Intveld says.

      But Intveld hopes to take the same approach to mining she does with her other endeavors — acknowledging the destructive past to make way for a better future. More

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      in Energy

      Manufacturing a cleaner future

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      Manufacturing had a big summer. The CHIPS and Science Act, signed into law in August, represents a massive investment in U.S. domestic manufacturing. The act aims to drastically expand the U.S. semiconductor industry, strengthen supply chains, and invest in R&D for new technological breakthroughs. According to John Hart, professor of mechanical engineering and director of the Laboratory for Manufacturing and Productivity at MIT, the CHIPS Act is just the latest example of significantly increased interest in manufacturing in recent years.

      “You have multiple forces working together: reflections from the pandemic’s impact on supply chains, the geopolitical situation around the world, and the urgency and importance of sustainability,” says Hart. “This has now aligned incentives among government, industry, and the investment community to accelerate innovation in manufacturing and industrial technology.”

      Hand-in-hand with this increased focus on manufacturing is a need to prioritize sustainability.

      Roughly one-quarter of greenhouse gas emissions came from industry and manufacturing in 2020. Factories and plants can also deplete local water reserves and generate vast amounts of waste, some of which can be toxic.

      To address these issues and drive the transition to a low-carbon economy, new products and industrial processes must be developed alongside sustainable manufacturing technologies. Hart sees mechanical engineers as playing a crucial role in this transition.

      “Mechanical engineers can uniquely solve critical problems that require next-generation hardware technologies, and know how to bring their solutions to scale,” says Hart.

      Several fast-growing companies founded by faculty and alumni from MIT’s Department of Mechanical Engineering offer solutions for manufacturing’s environmental problem, paving the path for a more sustainable future.

      Gradiant: Cleantech water solutions

      Manufacturing requires water, and lots of it. A medium-sized semiconductor fabrication plant uses upward of 10 million gallons of water a day. In a world increasingly plagued by droughts, this dependence on water poses a major challenge.

      Gradiant offers a solution to this water problem. Co-founded by Anurag Bajpayee SM ’08, PhD ’12 and Prakash Govindan PhD ’12, the company is a pioneer in sustainable — or “cleantech” — water projects.

      As doctoral students in the Rohsenow Kendall Heat Transfer Laboratory, Bajpayee and Govindan shared a pragmatism and penchant for action. They both worked on desalination research — Bajpayee with Professor Gang Chen and Govindan with Professor John Lienhard.

      Inspired by a childhood spent during a severe drought in Chennai, India, Govindan developed for his PhD a humidification-dehumidification technology that mimicked natural rainfall cycles. It was with this piece of technology, which they named Carrier Gas Extraction (CGE), that the duo founded Gradiant in 2013.

      The key to CGE lies in a proprietary algorithm that accounts for variability in the quality and quantity in wastewater feed. At the heart of the algorithm is a nondimensional number, which Govindan proposes one day be called the “Lienhard Number,” after his doctoral advisor.

      “When the water quality varies in the system, our technology automatically sends a signal to motors within the plant to adjust the flow rates to bring back the nondimensional number to a value of one. Once it’s brought back to a value of one, you’re running in optimal condition,” explains Govindan, who serves as chief operating officer of Gradiant.

      This system can treat and clean the wastewater produced by a manufacturing plant for reuse, ultimately conserving millions of gallons of water each year.

      As the company has grown, the Gradiant team has added new technologies to their arsenal, including Selective Contaminant Extraction, a cost-efficient method that removes only specific contaminants, and a brine-concentration method called Counter-Flow Reverse Osmosis. They now offer a full technology stack of water and wastewater treatment solutions to clients in industries including pharmaceuticals, energy, mining, food and beverage, and the ever-growing semiconductor industry.

      “We are an end-to-end water solutions provider. We have a portfolio of proprietary technologies and will pick and choose from our ‘quiver’ depending on a customer’s needs,” says Bajpayee, who serves as CEO of Gradiant. “Customers look at us as their water partner. We can take care of their water problem end-to-end so they can focus on their core business.”

      Gradiant has seen explosive growth over the past decade. With 450 water and wastewater treatment plants built to date, they treat the equivalent of 5 million households’ worth of water each day. Recent acquisitions saw their total employees rise to above 500.

      The diversity of Gradiant’s solutions is reflected in their clients, who include Pfizer, AB InBev, and Coca-Cola. They also count semiconductor giants like Micron Technology, GlobalFoundries, Intel, and TSMC among their customers.

      “Over the last few years, we have really developed our capabilities and reputation serving semiconductor wastewater and semiconductor ultrapure water,” says Bajpayee.

      Semiconductor manufacturers require ultrapure water for fabrication. Unlike drinking water, which has a total dissolved solids range in the parts per million, water used to manufacture microchips has a range in the parts per billion or quadrillion.

      Currently, the average recycling rate at semiconductor fabrication plants — or fabs — in Singapore is only 43 percent. Using Gradiant’s technologies, these fabs can recycle 98-99 percent of the 10 million gallons of water they require daily. This reused water is pure enough to be put back into the manufacturing process.

      “What we’ve done is eliminated the discharge of this contaminated water and nearly eliminated the dependence of the semiconductor fab on the public water supply,” adds Bajpayee.

      With new regulations being introduced, pressure is increasing for fabs to improve their water use, making sustainability even more important to brand owners and their stakeholders.

      As the domestic semiconductor industry expands in light of the CHIPS and Science Act, Gradiant sees an opportunity to bring their semiconductor water treatment technologies to more factories in the United States.

      Via Separations: Efficient chemical filtration

      Like Bajpayee and Govindan, Shreya Dave ’09, SM ’12, PhD ’16 focused on desalination for her doctoral thesis. Under the guidance of her advisor Jeffrey Grossman, professor of materials science and engineering, Dave built a membrane that could enable more efficient and cheaper desalination.

      A thorough cost and market analysis brought Dave to the conclusion that the desalination membrane she developed would not make it to commercialization.

      “The current technologies are just really good at what they do. They’re low-cost, mass produced, and they worked. There was no room in the market for our technology,” says Dave.

      Shortly after defending her thesis, she read a commentary article in the journal Nature that changed everything. The article outlined a problem. Chemical separations that are central to many manufacturing processes require a huge amount of energy. Industry needed more efficient and cheaper membranes. Dave thought she might have a solution.

      After determining there was an economic opportunity, Dave, Grossman, and Brent Keller PhD ’16 founded Via Separations in 2017. Shortly thereafter, they were chosen as one of the first companies to receive funding from MIT’s venture firm, The Engine.

      Currently, industrial filtration is done by heating chemicals at very high temperatures to separate compounds. Dave likens it to making pasta by boiling all of the water off until it evaporates and all you are left with is the pasta noodles. In manufacturing, this method of chemical separation is extremely energy-intensive and inefficient.

      Via Separations has created the chemical equivalent of a “pasta strainer.” Rather than using heat to separate, their membranes “strain” chemical compounds. This method of chemical filtration uses 90 percent less energy than standard methods.

      While most membranes are made of polymers, Via Separations’ membranes are made with graphene oxide, which can withstand high temperatures and harsh conditions. The membrane is calibrated to the customer’s needs by altering the pore size and tuning the surface chemistry.

      Currently, Dave and her team are focusing on the pulp and paper industry as their beachhead market. They have developed a system that makes the recovery of a substance known as “black liquor” more energy efficient.

      “When tree becomes paper, only one-third of the biomass is used for the paper. Currently the most valuable use for the remaining two-thirds not needed for paper is to take it from a pretty dilute stream to a pretty concentrated stream using evaporators by boiling off the water,” says Dave.

      This black liquor is then burned. Most of the resulting energy is used to power the filtration process.

      “This closed-loop system accounts for an enormous amount of energy consumption in the U.S. We can make that process 84 percent more efficient by putting the ‘pasta strainer’ in front of the boiler,” adds Dave.

      VulcanForms: Additive manufacturing at industrial scale

      The first semester John Hart taught at MIT was a fruitful one. He taught a course on 3D printing, broadly known as additive manufacturing (AM). While it wasn’t his main research focus at the time, he found the topic fascinating. So did many of the students in the class, including Martin Feldmann MEng ’14.

      After graduating with his MEng in advanced manufacturing, Feldmann joined Hart’s research group full time. There, they bonded over their shared interest in AM. They saw an opportunity to innovate with an established metal AM technology, known as laser powder bed fusion, and came up with a concept to realize metal AM at an industrial scale.

      The pair co-founded VulcanForms in 2015.

      “We have developed a machine architecture for metal AM that can build parts with exceptional quality and productivity,” says Hart. “And, we have integrated our machines in a fully digital production system, combining AM, postprocessing, and precision machining.”

      Unlike other companies that sell 3D printers for others to produce parts, VulcanForms makes and sells parts for their customers using their fleet of industrial machines. VulcanForms has grown to nearly 400 employees. Last year, the team opened their first production factory, known as “VulcanOne,” in Devens, Massachusetts.

      The quality and precision with which VulcanForms produces parts is critical for products like medical implants, heat exchangers, and aircraft engines. Their machines can print layers of metal thinner than a human hair.

      “We’re producing components that are difficult, or in some cases impossible to manufacture otherwise,” adds Hart, who sits on the company’s board of directors.

      The technologies developed at VulcanForms may help lead to a more sustainable way to manufacture parts and products, both directly through the additive process and indirectly through more efficient, agile supply chains.

      One way that VulcanForms, and AM in general, promotes sustainability is through material savings.

      Many of the materials VulcanForms uses, such as titanium alloys, require a great deal of energy to produce. When titanium parts are 3D-printed, substantially less of the material is used than in a traditional machining process. This material efficiency is where Hart sees AM making a large impact in terms of energy savings.

      Hart also points out that AM can accelerate innovation in clean energy technologies, ranging from more efficient jet engines to future fusion reactors.

      “Companies seeking to de-risk and scale clean energy technologies require know-how and access to advanced manufacturing capability, and industrial additive manufacturing is transformative in this regard,” Hart adds.

      LiquiGlide: Reducing waste by removing friction

      There is an unlikely culprit when it comes to waste in manufacturing and consumer products: friction. Kripa Varanasi, professor of mechanical engineering, and the team at LiquiGlide are on a mission to create a frictionless future, and substantially reduce waste in the process.

      Founded in 2012 by Varanasi and alum David Smith SM ’11, LiquiGlide designs custom coatings that enable liquids to “glide” on surfaces. Every last drop of a product can be used, whether it’s being squeezed out of a tube of toothpaste or drained from a 500-liter tank at a manufacturing plant. Making containers frictionless substantially minimizes wasted product, and eliminates the need to clean a container before recycling or reusing.

      Since launching, the company has found great success in consumer products. Customer Colgate utilized LiquiGlide’s technologies in the design of the Colgate Elixir toothpaste bottle, which has been honored with several industry awards for design. In a collaboration with world- renowned designer Yves Béhar, LiquiGlide is applying their technology to beauty and personal care product packaging. Meanwhile, the U.S. Food and Drug Administration has granted them a Device Master Filing, opening up opportunities for the technology to be used in medical devices, drug delivery, and biopharmaceuticals.

      In 2016, the company developed a system to make manufacturing containers frictionless. Called CleanTanX, the technology is used to treat the surfaces of tanks, funnels, and hoppers, preventing materials from sticking to the side. The system can reduce material waste by up to 99 percent.

      “This could really change the game. It saves wasted product, reduces wastewater generated from cleaning tanks, and can help make the manufacturing process zero-waste,” says Varanasi, who serves as chair at LiquiGlide.

      LiquiGlide works by creating a coating made of a textured solid and liquid lubricant on the container surface. When applied to a container, the lubricant remains infused within the texture. Capillary forces stabilize and allow the liquid to spread on the surface, creating a continuously lubricated surface that any viscous material can slide right down. The company uses a thermodynamic algorithm to determine the combinations of safe solids and liquids depending on the product, whether it’s toothpaste or paint.

      The company has built a robotic spraying system that can treat large vats and tanks at manufacturing plants on site. In addition to saving companies millions of dollars in wasted product, LiquiGlide drastically reduces the amount of water needed to regularly clean these containers, which normally have product stuck to the sides.

      “Normally when you empty everything out of a tank, you still have residue that needs to be cleaned with a tremendous amount of water. In agrochemicals, for example, there are strict regulations about how to deal with the resulting wastewater, which is toxic. All of that can be eliminated with LiquiGlide,” says Varanasi.

      While the closure of many manufacturing facilities early in the pandemic slowed down the rollout of CleanTanX pilots at plants, things have picked up in recent months. As manufacturing ramps up both globally and domestically, Varanasi sees a growing need for LiquiGlide’s technologies, especially for liquids like semiconductor slurry.

      Companies like Gradiant, Via Separations, VulcanForms, and LiquiGlide demonstrate that an expansion in manufacturing industries does not need to come at a steep environmental cost. It is possible for manufacturing to be scaled up in a sustainable way.

      “Manufacturing has always been the backbone of what we do as mechanical engineers. At MIT in particular, there is always a drive to make manufacturing sustainable,” says Evelyn Wang, Ford Professor of Engineering and former head of the Department of Mechanical Engineering. “It’s amazing to see how startups that have an origin in our department are looking at every aspect of the manufacturing process and figuring out how to improve it for the health of our planet.”

      As legislation like the CHIPS and Science Act fuels growth in manufacturing, there will be an increased need for startups and companies that develop solutions to mitigate the environmental impact, bringing us closer to a more sustainable future. More

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      in Environment

      Nonabah Lane, Navajo educator and environmental sustainability specialist with numerous ties to MIT, dies at 46

      by

      Nonabah Lane, a Navajo educator and environmental sustainability specialist with numerous MIT ties to MIT, passed away in October. She was 46.

      Lane had recently been an MIT Media Lab Director’s Fellow; MIT Solve 2019 Indigenous Communities Fellow; Department of Urban Studies and Planning guest lecturer and community partner; community partner with the PKG Public Service Center, Terrascope, and D-Lab; and a speaker at this year’s MIT Energy Week.

      Lane was a passionate sustainability specialist with experience spearheading successful environmental civic science projects focused in agriculture, water science, and energy. Committed to mitigating water pollutants and environmental hazards in tribal communities, she held extensive knowledge of environmental policy and Indigenous water rights. 

      Lane’s clans were Ta’neezahnii (Tangled People), born for Tł’izíłání (Manygoats People), and her maternal grandfathers are the Kiiyaa’aanii (Towering House People), and paternal grandfathers are Bįįh Bitoo’nii (Deer Spring People).

      Lane was a member of the Navajo Nation, Nenahnezad Chapter. At Navajo Power, she worked as the lead developer for solar and energy storage projects to benefit tribal communities on the Navajo Nation and other tribal nations in New Mexico. Prior to joining Navajo Power, Lane co-founded Navajo Ethno-Agriculture, a farm that teaches Navajo culture through traditional farming and bilingual education. Lane also launched a campaign to partner with local Navajo schools and tribal colleges to create their own water-testing capabilities and translate data into information to local farmers.

      “I had the opportunity to collaborate closely with Nonabah on a range of initiatives she was championing on energy, food, justice, water, Indigenous leadership, youth STEM, and more. She was innovative, entrepreneurial, inclusive, heartfelt, and positively impacted MIT on every visit to campus. She articulated important things that needed saying and expanded people’s thinking constantly. We will all miss her insights and teamwork,” says Megan Smith ’86, SM ’88, MIT Corporation life member; third U.S. chief technology officer and assistant to the president in the Office of Science and Technology Policy; and founder and CEO of shift7.

      In March 2019, Lane and her family — parents Gloria and Harry and brother Bruce — welcomed students and staff of the MIT Terrascope first-year learning community to their farm, where they taught unique, hands-on lessons about traditional Diné farming and spirituality. She then continued to collaborate with Terrascope, helping staff and students develop community-based work with partners in Navajo Nation. 

      Terrascope associate director and lecturer Ari Epstein says, “Nonabah was an inspiring person and a remarkable collaborator; she had a talent for connecting and communicating across disciplinary, organizational, and cultural differences, and she was generous with her expertise and knowledge. We will miss her very much.”

      Lane came to MIT in May 2019 for the MIT Solve Indigenous Communities Fellowship and Solve at MIT event, representing Navajo Ethno-Agriculture with her mother, Gloria Lane, and brother, Bruce Lane, and later serving as a Fellow Leadership Group member. 

      “Nonabah was an incredible individual who worked tirelessly to better all of her communities, whether it was back home on the Navajo Nation, here at MIT Solve, or supporting her family and friends,” says Alex Amouyel, executive director of MIT Solve. “More than that, Nonabah was a passionate mentor and caring friend of so many, carefully tending the next generation of Indigenous innovators, entrepreneurs, and change-makers. Her loss will be felt deeply by the MIT community, and her legacy of heartfelt service will not be forgotten.”

      She continued to be heavily involved across the MIT campus — named as a 2019 Media Lab Director’s Fellow, leading a workshop at the 2020 MIT Media Lab Festival of Learning on modernizing Navajo foods using traditional food science and cultural narrative, speaking at the 2022 MIT Energy Conference “Accelerating the Clean Energy Transition,” and taking part in the MIT Center for Bits and Atoms (CBA) innovation weekly co-working groups for Covid-response related innovations. 

      “My CBA colleagues and I enjoyed working with Nonabah on rapid-prototyping for the Covid response, on expanding access to digital fabrication, and on ambitious proposals for connecting emerging technology with Indigenous knowledge,” says Professor Neil Gershenfeld, director, MIT Center for Bits and Atoms.

      Nonabah also guest lectured for the MIT Department of Urban Studies and Planning’s Indigenous Environmental Planning class in Spring 2022. Professors Lawrence Susskind and Gabriella Carolini and teaching assistant Dení López led the class in cooperation with Elizabeth Rule, Chickasaw Nation member and professor at American University. 

      Carolini shares, on behalf of Susskind and the class, “During this time, our teaching team and students from a broad range of fields at MIT had the deep honor of learning from and with the inimitable Nonabah Lane. Nonabah was a dedicated and critical partner to our class, representing in this instance Navajo Power — but of course, also so much more. Her broad experiences and knowledge — working with fellow Navajo members on energy and agriculture sovereignty, as well as in advancing entrepreneurship and innovation — reflected the urgency Nonabah saw in meeting the challenges and opportunities for sustainable and equitable futures in Navajo nation and beyond. She was a pure life force, running on all fires, and brought to our class a dedicated drive to educate, learn, and extend our reference points beyond current knowledge frontiers.” 

      Three MIT students — junior Isabella Gandara, Alexander Gerszten ’22, and Paul Picciano MS ’22 — who worked closely with Lane on a project with Navajo Power, recalled how she shared herself with them in so many ways, through her truly exceptional work ethic, stories about herself and her family, and the care and thought that she put into her ventures. They noted there was always something new to feel inspired by when in her presence. 

      “The PKG Public Service Center mourns the passing of Nonabah Lane. Navajo Ethno-Agriculture is a valued PKG Center partner that offers MIT undergraduate students the opportunity to support community-led projects with the Diné Community on Navajo Nation. Nonabah inspired students to examine broad social and technical issues that impact Indigenous communities in Navajo Nation and beyond, in many cases leaving an indelible mark on their personal and professional paths,” says Jill S. Bassett, associate dean and director of the PKG Public Service Center.

      Lane was a Sequoyah Fellow of the American Indian Science and Engineering Society (AISES) and remained actively engaged in the AISES community by mentoring young people interested in the fields of science, engineering, agriculture, and energy. Over the years, Lane collaborated with leaders across tribal lands and beyond on projects related to agriculture, energy, sustainable chemicals, and finance. Lane had an enormous positive impact on many through her accomplishments and also the countless meaningful connections she helped to form among people in diverse fields.

      Donations may be made to a memorial fund organized by Navajo Power, PBC in honor of Nonabah Lane, in support of Navajo Ethno-Agriculture, the Native American nonprofit she co-founded and cared deeply for. More

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      in Environment

      MIT PhD students shed light on important water and food research

      by

      One glance at the news lately will reveal countless headlines on the dire state of global water and food security. Pollution, supply chain disruptions, and the war in Ukraine are all threatening water and food systems, compounding climate change impacts from heat waves, drought, floods, and wildfires.

      Every year, MIT’s Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) offers fellowships to outstanding MIT graduate students who are working on innovative ways to secure water and food supplies in light of these urgent worldwide threats. J-WAFS announced this year’s fellowship recipients last April. Aditya Ghodgaonkar and Devashish Gokhale were awarded Rasikbhai L. Meswani Fellowships for Water Solutions, which are made possible by a generous gift from Elina and Nikhil Meswani and family. James Zhang, Katharina Fransen, and Linzixuan (Rhoda) Zhang were awarded J-WAFS Fellowships for Water and Food Solutions. The J-WAFS Fellowship for Water and Food Solutions is funded in part by J-WAFS Research Affiliate companies: Xylem, Inc., a water technology company, and GoAigua, a company leading the digital transformation of the water industry.

      The five fellows were each awarded a stipend and full tuition for one semester. They also benefit from mentorship, networking connections, and opportunities to showcase their research.

      “This year’s cohort of J-WAFS fellows show an indefatigable drive to explore, create, and push back boundaries,” says John H. Lienhard, director of J-WAFS. “Their passion and determination to create positive change for humanity are evident in these unique video portraits, which describe their solutions-oriented research in water and food,” Lienhard adds.

      J-WAFS funder Community Jameel recently commissioned video portraitures of each student that highlight their work and their inspiration to solve challenges in water and food. More about each J-WAFS fellow and their research follows.

      Play video

      Katharina Fransen

      In Professor Bradley Olsen’s lab in the Department of Chemical Engineering, Katharina Fransen works to develop biologically-based, biodegradable plastics which can be used for food packing that won’t pollute the environment. Fransen, a third-year PhD student, is motivated by the challenge of protecting the most vulnerable global communities from waste generated by the materials that are essential to connecting them to the global food supply. “We can’t ensure that all of our plastic waste gets recycled or reused, and so we want to make sure that if it does escape into the environment it can degrade, and that’s kind of where a lot of my research really comes in,” says Fransen. Most of her work involves creating polymers, or “really long chains of chemicals,” kind of like the paper rings a lot of us looped into chains as kids, Fransen explains. The polymers are optimized for food packaging applications to keep food fresher for longer, preventing food waste. Fransen says she finds the work “really interesting from the scientific perspective as well as from the idea that [she’s] going to make the world a little better with these new materials.” She adds, “I think it is both really fulfilling and really exciting and engaging.”

      Play video

      Aditya Ghodgaonkar

      “When I went to Kenya this past spring break, I had an opportunity to meet a lot of farmers and talk to them about what kind of maintenance issues they face,” says Aditya Ghodgaonkar, PhD candidate in the Department of Mechanical Engineering. Ghodgaonkar works with Associate Professor Amos Winter in the Global Engineering and Research (GEAR) Lab, where he designs hydraulic components for drip irrigation systems to make them water-efficient, off-grid, inexpensive, and low-maintenance. On his trip to Kenya, Ghodgaonkar gained firsthand knowledge from farmers about a common problem they encounter: clogging of drip irrigation emitters. He learned that clogging can be an expensive technical challenge to diagnose, mitigate, and resolve. He decided to focus his attention on designing emitters that are resistant to clogging, testing with sand and passive hydrodynamic filtration back in the lab at MIT. “I got into this from an academic standpoint,” says Ghodgaonkar. “It is only once I started working on the emitters, spoke with industrial partners that make these emitters, spoke with farmers, that I really truly appreciated the impact of what we’re doing.”

      Play video

      Devashish Gokhale

      Devashish Gokhale is a PhD student advised by Professor Patrick Doyle in the Department of Chemical Engineering. Gokhale’s commitment to global water security stems from his childhood in Pune, India, where both flooding and drought can occur depending on the time of year. “I’ve had these experiences where there’s been too much water and also too little water” he recalls. At MIT, Gokhale is developing cost-effective, sustainable, and reusable materials for water treatment with a focus on the elimination of emerging contaminants and low-concentration pollutants like heavy metals. Specifically, he works on making and optimizing polymeric hydrogel microparticles that can absorb micropollutants. “I know how important it is to do something which is not just scientifically interesting, but something which is impactful in a real way,” says Gokhale. Before starting a research project he asks himself, “are people going to be able to afford this? Is it really going to reach the people who need it the most?” Adding these constraints in the beginning of the research process sometimes makes the problem more difficult to solve, but Gokhale notes that in the end, the solution is much more promising.

      Play video

      James Zhang

      “We don’t really think much about it, it’s transparent, odorless, we just turn on our sink in many parts of the world and it just flows through,” says James Zhang when talking about water. Yet he notes that “many other parts of the world face water scarcity and this will only get worse due to global climate change.” A PhD student in the Department of Mechanical Engineering, Zhang works in the Nano Engineering Laboratory with Professor Gang Chen. Zhang is working on a technology that uses light-induced evaporation to clean water. He is currently investigating the fundamental properties of how light at different wavelengths interacts with liquids at the surface, particularly with brackish water surfaces. With strong theoretical and experimental components, his research could lead to innovations in desalinating water at high energy efficiencies. Zhang hopes that the technology can one day “produce lots of clean water for communities around the world that currently don’t have access to fresh water,” and create a new appreciation for this common liquid that many of us might not think about on a day-to-day basis.

      Play video

      Linzixuan (Rhoda) Zhang

      “Around the world there are about 2 billion people currently suffering from micronutrient deficiency because they do not have access to very healthy, very fresh food,” says chemical engineering PhD candidate Linzixuan (Rhoda) Zhang. This fact led Zhang to develop a micronutrient delivery platform that fortifies foods with essential vitamins and nutrients. With her advisors, Professor Robert Langer and Research Scientist Ana Jaklenec, Zhang brings biomedical engineering approaches to global health issues. Zhang says that “one of the most serious problems is vitamin A deficiency, because vitamin A is not very stable.” She goes on to explain that although vitamin A is present in different vegetables, when the vegetables are cooked, vitamin A can easily degrade. Zhang helped develop a group of biodegradable polymers that can stabilize micronutrients under cooking and storage conditions. With this technology, vitamin A, for example, could be encapsulated and effectively stabilized under boiling water. The platform has also shown efficient release in a simulation of the stomach environment. Zhang says it is the “little, tiny steps every day that are pushing us forward to the final impactful product.” More