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    Chemists gain new insights into the behavior of water in an influenza virus channel

    In a new study of water dynamics, a team of MIT chemists led by Professor Mei Hong, in collaboration with Associate Professor Adam Willard, has discovered that water in an ion channel is anisotropic, or partially aligned. The researchers’ data, the first of their kind, prove the relation of water dynamics and order to the conduction of protons in an ion channel. The work also provides potential new avenues for the development of antiviral drugs or other treatments.

    Members of the Hong lab conducted sophisticated nuclear magnetic resonance (NMR) experiments to prove the existence of anisotropic water in the proton channel of the influenza M virus, while members of the Willard group carried out independent all-atom molecular dynamics simulations to validate and augment the experimental data. Their study, of which Hong was the senior author, was published in Communications Biology, and was co-authored by Martin Gelenter, Venkata Mandala, and Aurelio Dregni of the Hong Lab, and Michiel Niesen and Dina Sharon of the Willard group.

    Channel water and influenza virus

    The influenza B virus protein BM2 is a protein channel that acidifies the virus, helping it to release its genetic material into infected cells. The water in this channel plays a critical role in helping the influenza virus become infectious, because it facilitates proton conduction inside the channel to cross the lipid membrane.

    Previously, Hong’s lab studied how the amino acid histidine shuttles protons from water into the flu virus, but they hadn’t investigated the water molecules themselves in detail. This new study has provided the missing link in a full understanding of the mixed hydrogen-bonded chain between water and histidine inside the M2 channel. To curb the flu virus protein, the channel would have to be plugged with small molecules — i.e., antiviral drugs — so that the water pathway would be broken.

    In order to align the water-water hydrogen bonds for “proton hopping,” water molecules must be at least partially oriented. However, to experimentally detect the tiny amount of residual alignment of water molecules in a channel, without freezing the sample, is extremely difficult. As a result, the majority of previous studies on the topic were conducted by computational chemists like Willard. Experimental data on this topic were typically restricted to crystal structures obtained at cryogenic temperatures. The Hong lab adopted a relaxation NMR technique that can be employed at the much balmier temperature of around 0 degrees Celsius. At this temperature, the water molecules rotated just slowly enough for the researchers to observe the mobility and residual orientation in the channel for the first time.

    More space, more order

    The evidence yielded by Hong’s NMR experiments indicated that the water molecules in the open state of the BM2 channel are more aligned than they are in the closed state, even though there are many more water molecules in the open state. The researchers detected this residual order by measuring a magnetic property called chemical shift anisotropy for the water protons. The higher water alignment at low pH came as a surprise.

    “This was initially counterintuitive to us,” says Hong. “We know from a lot of previous NMR data that the open channel has more water molecules, so one would think that these water molecules should be more disordered and random in the wider channel. But no, the waters are actually slightly better aligned based on the relaxation NMR data.” Molecular dynamic simulations indicated that this order is induced by the key proton-selective residue, a histidine, which is positively charged at low pH.

    By employing solid-state NMR spectroscopy and molecular dynamics simulations, the researchers also found that water rotated and translated across the channel more rapidly in the low-pH open state than in the high-pH closed state. These results together indicate that the water molecules undergo small-amplitude reorientations to establish the alignment that is necessary for proton hopping.

    Inhibiting proton conduction, blocking the virus

    By using molecular dynamics simulations performed by Willard and his group, the researchers were able to observe that the water network has fewer hydrogen-bonding bottlenecks in the open state than in the closed state. Thus, faster dynamics and higher orientational order of water molecules in the open channel establish the water network structure that is necessary for proton hopping and successful infection on the virus’ part.

    When a flu virus enters a cell, it goes into a small compartment called the endosome. The endosome compartment is acidic, which triggers the protein to open its water-permeated pathway and conduct the protons into the virus. Acidic pH has a high concentration of hydrogen ions, which is what the M2 protein conducts. Without the water molecules relaying the protons, the protons will not reach the histidine, a critical amino acid residue. The histidine is the proton-selective residue, and it rotates in order to shuttle the protons carried by the water molecules. The relay chain between the water molecules and the histidine is therefore responsible for proton conduction through the M2 channel. Therefore, the findings indicated in this research could prove relevant to the development of antiviral drugs and other practical applications. More

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    Startup empowers women to improve access to safe drinking water

    In Ghana’s Northern Region, thousands of villages rely on water from artificial ponds during the region’s long dry season. The water is unsafe to drink and results in thousands of water-borne illnesses each year. Worse yet, the situation is totally preventable.
    Cheap, locally available water treatment solutions exist to make the region’s abundant surface water safely drinkable. The challenge lies in getting families in rural villages to use those solutions exclusively and over the long run.
    Those were the issues Kate Cincotta SM ’09 and Vanessa Green SM ’08, MBA ’11 studied as graduate students at MIT. In order to solve them at scale they created Saha Global, a nonprofit that increases consumption of clean drinking water by empowering local women in each community to start profitable water treatment businesses.
    Saha works with villages to determine a price for clean water that everyone can afford while also fairly compensating the women entrepreneurs for their work. The company then provides training to the women and educates the community about the importance of drinking treated water. Saha also makes a one-time donation of water tanks and buckets to its female entrepreneurs.
    Importantly, Saha continues monitoring water consumption in each village for 10 years after a new business forms, helping entrepreneurs through any challenges they run into. The approach ensures the company maximizes its impact as it scales.
    “We look at things in stages,” Cincotta says. “The first stage is access: opening every business that we can open to get everybody access to clean water. Once that phase is done, the focus is on clean water consumption. How do you get everyone drinking clean water exclusively? If you can achieve that, it’s really just making sure that businesses are making enough money to cover their maintenance costs and are staying open.”
    To date, Saha Global has trained more than 700 women to start businesses in 246 villages. The businesses provide clean drinking water to more than 100,000 people in communities that can’t afford large water treatment plants or modern plumbing systems.
    Saha is also having an impact on the women it partners with, who use the extra income to do things like send their children to school, buy cellphones, and fertilize their farms. The women also become leaders in their communities, gaining confidence as they provide a service that’s of vital importance to everyone around them.
    “This is an opportunity for the women in these settings to showcase their expertise and to give back to their community,” Cincotta says. “I think about times when I personally feel empowered, and it’s when someone looks to me for my expertise or my advice. We can see that happening with these women because this is something they lead in their community.”
    A model for impact
    In 2007, Cincotta enrolled in MIT’s Technology and Policy Program and began working in northern Ghana with Susan Murcott, an environmental engineer, social entrepreneur, and MIT D-Lab lecturer who runs a nonprofit that provides water filters to people in the region. The experience taught Cincotta about barriers to long-term adoption of water treatment technologies in the region’s rural villages.
    “We know how to treat water … and yet at that time, over a billion people still lacked access to safe water,” Cincotta says. “To me, it didn’t seem like a design problem; it was more this interplay between technology and policy and technology and society, and how we get the tech to the people who need it.”
    During a trip to the region in 2008, she met Green, another graduate student working with Murcott to understand consumer preferences around water treatment technologies.
    Cincotta and Green began a research collaboration in the summer of 2008, finding that many Ghanians stopped using their ceramic water filters after they clogged or broke, despite the fact that both problems were easily fixable.
    Still, resolving those issues by monitoring each deployment seemed too time- and labor-intensive for a traditional nonprofit.
    “When you’re a nonprofit or social enterprise trying to distribute a product widely, to maybe a billion people who need clean water, that follow up can get extremely expensive,” Cincotta says.
    To reduce those costs and simplify follow up efforts, the founders decided to invest in one water treatment point in each community. Rather than relying on handouts, the treatment centers would be self-sustaining businesses. The more successful they were, the more clean water would be consumed in the community. And the founders knew just the people to partner with.
    Three women in each village are nominated to build and run each local water treatment business. The women spend about five hours a week on it, and typically earn $1 dollar a week — a significant amount in a region where many families live on less than $2 a day.
    “Most of them know every family in their community and when they’re going to come by and how much water that means they’re going to need to treat that day,” Cincotta says. “They very quickly know way more about running the business and their community than Saha does, and you can see what that does for someone, getting that expertise and using it to serve people they care about.”
    The company’s training shows entrepreneurs how to use the treatment materials, how to fit the water treatment process into their lives, how to announce when water is available, and how to price the water to cover expenses and compensate them for their time. During that period, the company will also go door-to-door in the community to distribute the buckets and educate people on the new business.
    “It all culminates in this big opening day, which is always so exciting,” Cincotta says. “The whole community comes out to get water. It’s also very busy for the entrepreneurs. And it’s basically up and running from there.”
    Saha supports the entrepreneurs with customer care teams that help them through business problems, technicians that train women to repair tanks, and testers who periodically ensure entrepreneurs’ tanks are free of E. coli. The company also continues educating the community on the importance of only drinking clean water.
    “Our goal is always exclusive clean water consumption,” Cincotta says. “We want everyone in every community we work in to drink clean water all the time. We’re not there yet, and so we’re really trying to understand who is coming to buy water frequently and who isn’t, and of the people that aren’t, what are the barriers they’re facing to clean water consumption?”
    Each of Saha’s 246 communities is receiving 10 years of support, and the company will only expand if it can offer the same guarantee to new communities.
    Fulfilling a mission
    Saha started 70 new businesses in 2019, its best year yet. Last year, the Ghanaian government responded to Covid-19 disruptions by mandating that all citizens be provided clean drinking water for free. The government has said it will reimburse Saha’s entrepreneurs for the sales they make, but so far Saha has been forced to fundraise to compensate entrepreurs.
    On the plus side, Cincotta says the company has observed six times more clean water consumption during the pandemic in its communities.
    Saha’s goal is to help everyone in Ghana’s Northern Region who still needs clean water, which amounts to about 800,000 people, by 2025. Cincotta also believes Saha’s model can work anywhere in the world where surface water is abundant.
    “We really see ourselves as part of this bigger goal of universal water access,” Cincotta says, noting Saha’s model works best in villages of 400 to 1,000 people in which water treatment plants may be impractical. “You can’t leave anyone behind, and so you’re really going to need lots of different actors working together. We’re excited about the role we can play in that.” More

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    Improving sanitation for the world’s most vulnerable people

    Last year, women visiting a neonatal clinic at a hospital in Kiboga, Uganda, began using two waterless, standalone bathrooms that offered a cleaner and more private alternative to the pit latrines that are standard in the region.
    The deployment was the culmination of years of work by the startup change:WATER Labs, co-founded by two MIT research scientists — and its success showed the company’s potential to improve lives far beyond Uganda.
    Half of the world’s population lacks access to toilets that safely manage human waste, with women and children bearing the brunt of the consequences. A child dies every 15 seconds from water-related diseases like diarrhea and cholera. Women and girls without private bathrooms close to their homes are susceptible to high rates of sexual violence. Globally, 45 percent of schools lack proper bathroom facilities, one reason 20 percent of girls drop out of school by the time they start menstruating.
    The small but determined team behind change:WATER Labs believes the solution to these problems is an inexpensive, no-flush toilet that can be dropped into any location and work without external power. The toilet, which the company calls the iThrone, uses a proprietary material to evaporate the water content of human waste, shrinking waste by 95 percent, thus preventing waste discharge and simplifying waste collection.
    The breathable material takes advantage of the natural tendency of water molecules to move from areas of high moisture to areas of low moisture. CEO and co-founder Diana Yousef, who is also a research affiliate at MIT, says the iThrone allows for waste collection once or twice a month as opposed to every day, transforming the economics of distributed sanitation in low-resource communities.
    “We’re essentially turning human waste into clean molecular water, and what’s left over gets collected much less frequently at much lower cost,” Yousef says. “The solution helps customers managing sanitation to be much more scalable, much more sustainable, and much more profitable.”
    Today change:WATER Labs has promising early trial results to go along with support from a host of companies, NGOs, and governments. But back when the company was nothing more than an idea, MIT played a pivotal role in making the iThrone concept a reality.
    A unique partnership
    The seed of change:WATER Labs was planted for Yousef while working on a water treatment initiative with NASA in 2009. Although the project explored ways to recycle water for space agriculture, Yousef wondered if any of the approaches could be used to improve water sustainability in the developing world.
    Five years later, she finally put the idea to paper, pitching an early version at MIT’s Water Innovation Prize and the MIT IDEAS Social Innovation Challenge. The experience helped her connect with others at MIT who were interested in the idea, including co-founder Huda Elasaad, a research affiliate in MIT’s D-Lab. Yousef, who earned her undergraduate degree at Harvard University, a PhD at Cornell University, and MBA and MIA degrees from Columbia University, eventually received seed funding to explore the idea from IDEAS and the MIT PKG Center. The support allowed her team to gain access to lab facilities for early testing.
    “[The early support from MIT] was a game-changer for us, because you start to have doubts about whether what you’re doing is possible, and when some other entity like MIT takes a bet on you, you start to believe it yourself,” says Yousef, who notes she didn’t have the resources to pursue the idea on her own and was working on a prototype in her kitchen.
    MIT’s relationship with the company has continued to evolve in the years since that early bet. MIT’s Environment, Health, and Safety (EHS) Office has helped the startup develop its waste treatment system, and the company benefits from its association with MIT D-Lab, where it collaborates with MIT students from diverse backgrounds.
    “We’ve been so very lucky to find such support and collaborators at MIT,” Yousef says. “MIT provides a truly unique ecosystem that cultivates partnerships between innovators within and around MIT to catalyze world-changing innovations. Our breakthrough wouldn’t have been possible without the support from D-Lab, EHS, the PKG Center, and our other partners at MIT.”
    On a mission for change
    Change:WATER Labs’ toilets were used by about 400 people per week in Uganda before the project was cut short by Covid-19. Yousef says the iThrones proved safe, with minimal odor and no leakage, showing they could be placed close to densely populated areas.
    “We have the potential to put safe, hygienic, clean toilets in places that are crowded and close to where people are, and that’s been one of the challenges with other solutions, like composting toilets and others, that don’t fit in crowded communities,” she says.
    The toilets also reduced daily waste volumes so much that they were able to operate for weeks at a time without being serviced. Overall, Yousef says feedback from users was overwhelmingly positive as the iThrones provided a safer, cleaner alternative to pit latrines located on the top of a remote hill.
    Although travel restrictions have put other iThrone pilots on hold, change:WATER Labs has received funding from the Bill and Melinda Gates Foundation, the United Nations Development Program, and the Turkish government to install its toilets in refugee communities in Turkey later this year.
    Private companies have also expressed interest, including two large construction contractors looking to put iThrones in low-income homes in Central America, and two Indian companies seeking to put iThrones in port-a-potties and on transportation and maritime equipment.
    Yousef says that inbound interest is indicative of the large global need and pent-up demand for better sanitation options.
    “We need new solutions that contain and eliminate human waste while also reducing the amount of water that gets consumed, preventing pollution,” Yousef says. “We solve all of that.”
    Yousef says the company never would have reached this point without the MIT community, which she commends for embracing her effort even though she is not an alumna.
    “MIT’s willingness to open up its community to the innovators around it allows for things to happen that really don’t happen anywhere else,” she says. “It’s special to be here and it’s really amplified what we’re trying to do.” More

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    The catalyzing potential of J-WAFS seed grants

    “A seed grant for a risky idea that is mission-driven goes a long way.” 
    These are the words of Fadel Adib, an associate professor of media arts and sciences and of electrical engineering and computer science and a 2019 recipient of a two-year seed grant from the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS) at MIT. His work is in wireless sensing, where his research group has largely focused on developing fundamental technology. It is technology with a mission, however one that — until the J-WAFS seed grant — had largely focused on supporting human health and the environment, but not yet food. “I started with an early project applied to food, but the results were not enough to publish. When I saw the J-WAFS seed grant request for proposals I realized that this was a great way for [my research group] to expand our efforts in the food sector.” The resulting research project, a wireless sensor that uses RFID technology to measure the safety and nutritional quality of food and beverage products, has since inspired him and his research group to delve deeper into food-sector research, including exploring potential applications for sustainable aquaculture.
    Adib’s story is one of many that J-WAFS principal investigators — especially junior faculty — have shared about the impact of the seed grant program, illustrating how influential this grant can be. Funding is an essential research driver, with the availability of resources often defining the subject area and scope of individual projects, as well as entire careers. Seed grants in particular can be transformational, especially for junior faculty such as Adib, for the opportunity they provide for exploration.
    J-WAFS catalyzes research across all disciplines and programs at MIT in order to find solutions to urgent global water and food systems challenges. For MIT faculty coming from technology-dominant disciplines, this emphasis on impact can be invigorating. For Adib, “it allowed [my lab] to do more interdisciplinary work … starting with the problem first, rather than the technique.”
    Mathias Kolle, Rockwell Career Development Professor in the Department of Mechanical Engineering and a J-WAFS grantee, agrees. Kolle received a J-WAFS seed grant in 2017 to develop novel, light-diffusing fibers to increase the energy efficiency of industrial algae production in order to improve its viability as an affordable, environmentally sustainable solution for food and fuel. He comments that the grant proposal and review process itself helped him connect the dots between the technology milestones he sought to pursue and the social impact potential of the project. He credits the prompts sent by the expert reviewers convened by J-WAFS in the final stages of the grant process for “helping me create a pretty convincing picture of why work on algae is important.” Joseph Sandt SM ’15, PhD ’20 collaborated with Kolle throughout his PhD program in mechanical engineering, making the project the focus of his thesis. Kolle comments, “Joseph was very fired-up when the J-WAFS project came up.” The research allowed him to build on his existing interest in sustainability while working on an engineering project that still involved a lot of tinkering.
    A J-WAFS seed grant inspired yet another junior faculty member to pursue water and food research for the first time: Julia Ortony, the Finmeccanica Assistant Professor in Materials Science and Engineering.   The 2018 grant she received was her first major grant as a new junior faculty member in the Department of Materials Science and Engineering — one that allowed her to work on applied instead of fundamental research for the very first time. “[The J-WAFS seed project] was the first time I really thought about the end product,” she says. Through it, Ortony and her lab develop molecule-based nanofiber hydrogels that are able to bind arsenic and other heavy metals in order to clean drinking water. Ortony recalls, “at the time we received the grant, we were a very new group. It was hard for us to get a big federal grant without preliminary data.”
    The J-WAFS grant served as an important catalyst. Data from the J-WAFS project drove another successful grant, the Professor Amar G. Bose Research Grant, which enabled the continuation of the J-WAFS research in a different state of matter. “We wouldn’t have been able to explore solid state nanomaterials without the knowledge we gained from the J-WAFS project,” Ortony comments. Since then, she has received additional follow-on funding in the form of a CAREER award from the National Science Foundation, which will enable her research team to develop their understanding of the fundamentals of the nanofiber materials in order to learn how to tune it to even more effectively pull heavy metal contaminants from water. “The J-WAFS seed grant has allowed our group to make a right turn and think about the goal of our research from an applications perspective,” comments Ortony. “We are now doing this in other domains too, outside of water purification.”
    The mission-oriented focus of the J-WAFS seed grant attracted another junior faculty member: Joann de Zegher, the Maurice F. Strong Career Development Professor at the MIT Sloan School of Management. Joann joined MIT in the fall of 2018 after completing a PhD and postdoc at Stanford University. While there, she had been working on the sustainability of global supply chains, focusing on contract design that more effectively aligns incentives with global sourcing and sustainability. Unlike Kolle, Adib, and Ortony, de Zegher had already begun working in the food sector, having pivoted toward understanding supply chain management to support the sustainability of informal food systems. Her 2019 J-WAFS seed grant is supporting the development of mobile supply chain platforms to support sustainable palm oil production by smallholder farmers in Indonesia.
    Fieldwork is essential to de Zegher’s research, yet “fieldwork is expensive,” she says, and notes that “When it comes to the study of informal supply chains, like smallholder farmers in Indonesia, it’s hard to find opportunities to fund things like travel and student research assistants.” This is where her 2019 J-WAFS seed grant has proved influential. It “provides an important complement to the funding from foundations that supports field operations.” The J-WAFS funding for travel, fieldwork, and a full-time student supporting data collection and analysis has enabled “that extra-mile data analysis that could have been missing” had de Zegher not received the grant.
    The solutions-oriented approach that the seed grant program takes welcomes cross-disciplinary, collaborative approaches to problem-solving. J-WAFS has funded many interdepartmental research collaborations in which junior faculty have been involved. One such collaboration is between David Des Marais, Gale Assistant Professor of Civil and Environmental Engineering, and Caroline Uhler, the Henry L. and Grace Doherty Associate Professor of Electrical Engineering and Computer Science. They are working on a J-WAFS-backed project to find the genetic foundations of plant tolerance to the stresses of heat and drought. Comments Des Marais, “collaboration with Caroline is transformational. The methods that she developed through the J-WAFS project are changing the way I think about how to tackle my research questions.” 
    Another junior faculty member from civil and environmental engineering, Benedetto Marelli, has found a research collaboration enabled by a J-WAFS seed grant impactful. Marelli is collaborating with A. John Hart, a professor in the Department of Mechanical Engineering. The two are developing an edible, silk-based food safety sensor that changes color when exposed to bacteria. “Teaming up with a senior faculty member is a good way for junior faculty members to let others know what you are doing,” says Marelli. What is more, for him the experience has involved a lot of mentoring. “Working with John [on the project], I was able to see how a really developed lab operates. As a junior faculty member, you need to immediately learn about finances, mentoring, teaching, and advising. It’s overwhelming.” Working so closely with Hart on their seed grant project, Marelli has learned from his example and shortened his own learning curve.
    These few examples of how J-WAFS seed grants have influenced junior faculty at MIT provide a snapshot of the range of water and food systems research topics being pursued across the Institute. The catalyzing potential of J-WAFS seed grants not only supports these faculty members’ career advancement, but also helps to push the boundaries of water and food systems research overall. In Joann de Zegher’s words, seed grant-funded research is “early-stage research — you don’t know how it’s going to play out.” In order to go after some of the most challenging problems in water and food systems, “you need that freedom and flexibility.” More

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    Brewing up a dirty-water remedy (and more) with kombucha-inspired biosensors

    Like many of his colleagues in the Department of Biological Engineering, graduate student Tzu-Chieh “Zijay” Tang employs microbes and synthetic biology — redesigning the genetic systems of organisms — in his research. However, his research goals are something of an outlier in his department: water quality applications.
    “I feel like there’s a huge imbalance of talent, at least at MIT,” says Tang, a fifth-year doctoral student. “A lot of people go into the biomedical field, and very few take on environmental issues.” To him, problems like climate change or food and water security are the most pressing challenges, and present great opportunities for students in biological engineering to make a difference. While interested in the environment and inspired by the natural world since a young age, he came to appreciate these issues even more, he says, as a result of his experience in 2017 as one of three inaugural fellows through the Fellowship for Water Solutions program at the MIT Abdul Latif Jameel Water and Food Systems Lab (J-WAFS). He points to J-WAFS as a key contributor to raising the profile of environmental research on campus and shifting the imbalance: “J-WAFS really has a vision of a sustainable future, and has been the best supporter of our research — and of me personally, as a researcher.”
    When Tang first came to MIT after studying materials science as a master’s student in Abu Dhabi, he joined the Mediated Matter group in the Media Lab. He was excited by the prospect of bioengineering novel materials under the principal investigator, Associate Professor Neri Oxman, “an amazing designer with great visions about how to make materials inspired by nature.” But after a few months, he realized that innovation in biological research, which occurs on a time frame of months to years, can’t keep pace with design deadlines, which tend to be on the order of weeks. Oxman’s group generally worked with fully developed bioengineered systems. Tang, however, preferred to innovate on the fundamental biology itself, and moved to the synthetic biology group of Tim Lu, associate professor of biological engineering and electrical engineering and computer science. Not one to limit his playing field, Tang still chats with Media Lab researchers to glean inspiration.
    And Tang’s collaborative spirit extends far afield. A MISTI Seed Grant and a summer at Imperial College London grew into a cross-Atlantic effort to develop living membranes with microbes, in a process inspired by the fermented beverage kombucha. Sweet tea is turned into acidic, fizzy kombucha by a symbiotic culture of bacteria and yeast (SCOBY), which exists in a gelatinous biofilm composed largely of cellulose produced by the bacteria themselves.
    The system is self-assembling and requires only a cheap sugar-based solution to maintain, properties that greatly appealed to Tang and his collaborators. Working from the kombucha principle, they developed Syn-SCOBY: a sturdy, cellulose-based biofilm created by and encapsulating a co-culture of engineered microbes. One version of the Syn-SCOBY contained yeast that could detect and degrade the environmental pollutant β-estradiol, but the team emphasized that the modularity of the system meant that it could be customized to target a wide variety of applications.
    “People in the lab came to me asking if I could incorporate peptides [amino acid chains] that can bind coronavirus particles into the Syn-SCOBY material,” Tang recalls. “I think this could probably be done quite quickly. That’s why I think developing platform technologies is so useful: you can adapt to different emergencies.” While Tang is well-versed in developing biological materials to address water contamination, it’s in pathogen detection where biosensors have an even greater edge over other more established measurement technology, he says. And while mass spectrometers can detect chemical pollutants reliably, if not necessarily cheaply or in the field, optimizing them to measure biological particles such as viruses has thus far proved difficult.
    Tang has already achieved recognition for his research accomplishments — he won a Lemelson-MIT Prize in the “Eat It!” category for his Syn-SCOBY filters. However, what he really wants is to see academic research translated to real applications. One big challenge is scalability, which Tang aims to avoid with his kombucha-inspired biomaterial. Syn-SCOBY is self-replicating, robust, and easy to make. Tang also hopes that the existence of thousands of kombucha homebrewers will make it easier to connect with the public and get them excited about this research.
    Four years ago, Tang started developing biosensors in the form of bacteria-containing hydrogel beads. The bacteria are engineered to light up in the presence of water contaminants (he tested this with, among other samples, Charles River water). Formulating the hydrogel was a key aspect of the project: Tang needed the material to not only protect and feed the bacteria, but also to prevent the bacteria from leaking out. Tang continued iterating on his ideas during his J-WAFS fellowship, and has finished developing a bead formulation that not only meets his design requirements, but can be easily adapted to host different microbes.
    With real-world applications of his inventions ever on his mind, Tang sought advice on use-case scenarios from industry experts, connections that were made possible through the fellowship’s funder, the international water technology company Xylem. For example, Tang gleaned from the company’s scientists which contaminants were actually of interest to industry, which helped him pick cadmium as a test of the beads’ potential real-world use. Furthermore, he learned that while the beads cannot report measurements as precisely as the gold standard of mass spectrometry, they are much cheaper and much more portable; at the same time, the beads are more precise than probes, which are the current go-to for preliminary testing.
    Presently, Tang does not have plans to take his bacteria beads to market, but is nonetheless brainstorming ways to improve them: He sees a potential to increase the system’s sensitivity by incorporating new microbe engineering methods developed in the lab of MIT biological engineering Professor Christopher Voigt. As for Syn-SCOBY, Tang says he might explore the technology’s startup potential through the Blueprint entrepreneurship program offered by The Engine, the startup incubator founded by MIT.
    Tang is also contemplating expanding beyond the field of biosensors after graduating in the fall. He feels a strong impetus toward climate change research, especially in advancing carbon removal technology. It’s another area where he sees a yawning gap between academia and application, as well as a long way to go in terms of scalability. In this regard, Tang says the ability of biological systems to self-propagate gives them an advantage over mechanical methods of carbon capture. But he cautions that this same self-propagation makes strict biocontainment of any engineered organisms a vital aspect of any system that is deployed — an aspect that Tang took pains to guarantee in his Syn-SCOBY and microbial hydrogel systems, and an aspect that he will continue to push for in his future work. More

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    Reducing inequality across the globe and on campus

    At a young age, Orisa Coombs pledged to use her engineering knowledge to reduce inequality. The summer after her first year of high school, she found herself grappling with the harsh realities of systemic racism after the death of Michael Brown. Brown’s death altered Coombs’ world view and reshaped how she approached her own role in society.“At 15, the intense pain and sense of injustice I felt introduced me to the collective trauma of the Black experience,” says Coombs. “I knew I needed to dedicate my engineering career to issues of oppression and inequality.”
    This driving force to make a difference in the world led her to pursue a degree in mechanical engineering at MIT.
    “I didn’t want to limit myself to working on a single discipline. There is a design aspect to everything, so I will be capable of working on almost any problem from a mechanical engineering perspective,” she adds.
    Once at MIT, Coombs explored research opportunities that improved the lives of others. Her work on medical devices in the MIT Media Lab and with a startup helping rural dairy farmers in India both had a tangible impact, but didn’t quite satisfy her goal of reducing inequality and making a difference on a global scale.Her experience in 11.005 (Introduction to International Development) helped Coombs narrow her research focus to issues affecting the developing world. In particular, she started exploring how climate change disproportionately impacts people of color in developing countries.
    “I was seeking research projects that had a connection to climate change and would allow me to develop numerical computation skills,” she says.
    This pursuit led her to an undergraduate research opportunity (UROP) in the lab of John Lienhard, the Abdul Latif Jameel Professor of Water and Mechanical Engineering. Lienhard’s group develops energy-efficient methods of producing clean water.
    Water scarcity has become a global crisis, particularly in developing countries that are disproportionately impacted by climate change. For her UROP, Coombs joined Lienhard’s efforts to address water scarcity through desalination, the process of turning seawater or brackish water into potable water. 
    “It is a fundamental injustice that access to water is not universal,” says Coombs. “Water research sits at the intersection of technology and class-based struggles, while also capitalizing on my fascination with thermofluids engineering.”
    Addressing global water scarcity
    Coombs’ UROP project focused on a new method of desalination known as osmotically assisted reverse osmosis — or OARO. The OARO process requires less energy and is lower-cost than typical reverse osmosis, making it a promising option for reducing water scarcity in developing nations.
    Researchers, however, still don’t understand how membrane diffusion works in OARO, leading to inaccurate performance models. Coombs utilized her background in computation to develop an improved model.
    As a Course 2-A (Engineering) major, Coombs’ concentration within mechanical engineering is numerical computation. Her OARO research afforded her the opportunity to apply her numerical computation skills to a real-world project. The resulting computational model of OARO membrane diffusion correlated with experimental data better than existing models.
    Coombs and Lienhard hope this model will lead to improved desalination systems in the future, which in turn could reduce water scarcity in developing nations.
    “The idea is that eventually we can make desalination a more effective primary water source, especially once fresh water resources are depleted. It’s really promising in terms of how we can change the water landscape and have real impact,” says Coombs.
    Coombs presented her model at the 2020 Mechanical Engineering Research Exhibition, where she won the First Place Presenter prize.
    “Orisa’s proactiveness and innate interest in research, coupled with her unfailing work ethic, quickly made her an indispensable member of our team,” says Lienhard, “and as I have learned more about Orisa, I have found that she also has a deep commitment to social equity.”
    While water scarcity continues to be a driving force in her academic career, Coombs has also been exploring this commitment to equity closer to home at MIT.
    Combating food insecurity
    During her first year at MIT, Coombs realized how food accessibility impacted individuals in her own friend group. A program called Class Awareness Support and Equality (CASE) at MIT sent grocery care packages to individuals experiencing food insecurity at MIT. When she started noticing some of her friends receiving packages from CASE, she realized just how pervasive the problem was.
    Coombs joined CASE as head of food accessibility to help address food insecurity experienced by members of the MIT community. Since her sophomore year, she has been working with administrators across MIT on developing initiatives and programs to help food-insecure students.
    Her first project as a member of CASE was to launch small food pantries in dorms that don’t have dining halls. She then shifted her focus to MIT’s on-campus grocery store as a member of the TechMart Advisory Group. She also works with administration on the Food Security Committee to identify further strategies to eradicate hunger.
    While her desalination research helps her address inequality on a global scale, her work through CASE has helped her develop solutions in her own community.
    “Working with CASE has been part of my journey to realizing that I really am passionate about making those positive changes around me, not just on a global scale,” says Coombs.
    Leading the Black Students’ Union through crisis
    Last spring, Coombs took on another leadership position to make positive changes across the MIT community as co-chair of the Black Students’ Union (BSU). Shortly after starting as co-chair, Coombs found herself at the helm of the BSU’s response to two crises in the Black community: a pandemic that disproportionately impacted communities of color and protests in the wake of George Floyd’s murder.
    Almost overnight, members of the MIT community turned to Coombs for feedback and leadership on behalf of the BSU.
    “When I got the role of BSU co-chair, I was not expecting this year to turn out this way,” she says. Coombs seized the opportunity to lead by joining student leaders in writing the Save Black Lives Petition and working closely with senior administration to shape MIT’s response to systemic and institutional racism.
    Since last summer, Coombs has helped ensure that MIT’s BSU has an active role in composing the Institute’s 10-year plan to combat racism internally and explore alternatives to current police response practices on campus. She also works on the Institute Steering Committee for Diversity, Equity, and Inclusion as one of three undergraduate representatives. 
    “Discussing our values is important, but I want to make sure that we take action. I’m always trying to stay focused on our goals and do right by my community,” says Coombs.
    As Coombs looks to the future after graduating this spring, she hopes to continue working on global problems like water scarcity at graduate school. She also sees a chance to have impact on future generations of mechanical engineering students.
    “As a Black woman in STEM, I don’t have many role models who look like me. I am excited to provide the mentorship and representation I did not have to the next generation,” she adds. More