Aurelia Butler

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    in Environment

    Study: Extreme heat is changing habits of daily life

    Extreme temperatures make people less likely to pursue outdoor activities they would otherwise make part of their daily routine, a new study led by MIT researchers has confirmed.

    The data-rich study, set in China, shows that when hourly temperatures reach 30 degrees Celsius (86 degrees Fahrenheit), people are 5 percent less likely to go to public parks, and when hourly temperatures hit 35 C (95 F), people are 13 percent less likely to go to those parks.

    “We did observe adaptation,” says Siqi Zheng, an MIT professor and co-author of a new paper detailing the study’s findings. She adds: “Environmental hazards hurt the daily quality of life. Yes, people protect themselves [by limiting activity], but they lose the benefit of going out to enjoy themselves in nature, or meeting friends in parks.”

    The research adds to our knowledge about the effects of a warming climate by quantifying the effects of hot temperatures on the activity of people within a given day — how they shift their activities from hotter to cooler time periods — and not just across longer periods of time.

    “We found that if we take into account this within-day adaptation, extreme temperatures actually have a much larger effect on human activity than the previous daily or monthly estimations [indicate],” says Yichun Fan, an MIT doctoral candidate and another of the paper’s co-authors.

    The paper, “Intraday Adaptation to Extreme Temperatures in Outdoor Activity,” is published this week in Nature Scientific Reports. The authors are Fan, a doctoral student in MIT’s Department of Urban Studies and Planning (DUSP); Jianghao Wang, a professor at the Chinese Academy of Sciences; Nick Obradovich, chief scientist at Project Regeneration; and Zheng, who is the STL Champion Professor of Urban and Real Estate Sustainability at MIT’s Center for Real Estate and DUSP, and faculty director of the MIT Center for Real Estate.

    To conduct the study, the researchers used anonymized data for 900 million cellphone users in China in 2017, studying a total of 60 billion separate cellphone location queries per day available through the technology firm Tencent. With this data, the scholars also examined activity in 10,499 parks across the country, comparing useage totals across a range of conditions. And they obtained temperature data from about 2,000 weather stations in China.

    Ultimately, as the scholars write in the paper, they were able to “document large and significant activity-depressing and activity-delaying effects” on park visits as a result of ultrahot temperatures.

    “People have intraday adaptation patterns that hadn’t been documented in the previous literature,” Fan says. “These have important implications about people’s heat exposure and how future climate change will affect people’s activity and health.”

    As Zheng points out, altered use of public spaces affects daily routines not only in terms of individual activity and exercise, but also in terms of social and community life.

    “Extreme climates will reduce people’s opportunities to socialize in cities, or just watch kids playing basketball or soccer, which is not good,” she says. “We want people to have a wide-ranging urban life. There is a social cost to this adaptation.”

    As the research indicates, people clearly adapt to temperature spikes. The data also show that evening use of parks increases on extremely hot days, but only after conditions have cooled down. While that seems like a beneficial adaptation to very hot weather, the scholars citing existing research suggest people may sleep less as a result of making this kind of change to their daily routines.

    “Adaptation also has its own cost,” Fan says. “People significantly increased their nighttime outdoor activity, which means they delayed their nighttime, which will have a significant health implication, when you consider the potential sleep disruption.”

    All told, the study provides data, and a method, for better characterizing the effects on climate change on human activity in detail.

    “If we have more and more granular data about future climate scenarios, they support better predictions about these scenarios, reflecting people’s dynamic behaviors, and the health implications,” says Fan, whose doctoral research incorporates this work and other related studies on climate and urban activity.

    The researchers also note that the research methods used in this study could be applied to additional future studies of many other aspects of urban life, including street-level retail activities, and other things with implications for economic activity, real estate, and urban planning.

    “This relates to many other issues,” Zheng says.

    Jianghao Wang received funding from the National Key Research and Development Program of China, the National Natural Science Foundation of China, and the Youth Innovation Promotion Association of the Chinese Academy of Sciences. More

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    in Environment

    Moving water and earth

    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

    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 Environment

    Sustainable supply chains put the customer first

    When we consider the supply chain, we typically think of factories, ships, trucks, and warehouses. Yet, the customer side is equally important, especially in efforts to make our distribution networks more sustainable. Customers are an untapped resource in building sustainability, says Josué C. Velázquez Martínez, a research scientist at MIT Center for Transportation and Logistics. 

    Velázquez Martínez, who is director of MIT’s Sustainable Supply Chain Lab, investigates how customer-facing supply chains can be made more environmentally and socially sustainable. One way is a Green Button project that explores how to optimize e-commerce delivery schedules to reduce carbon emissions and persuade customers to use less carbon-intensive four- or five-day shipping options instead of one or two days. Velázquez Martínez has also launched the MIT Low Income Firms Transformation (LIFT) Lab that is researching ways to improve micro-retailer supply chains in the developing world to provide owners with the necessary tools for survival.  

    “The definition of sustainable supply chain keeps evolving because things that were sustainable 20 to 30 years ago are not as sustainable now,” says Velázquez Martínez. “Today, there are more companies that are capturing information to build strategies for environmental, economic, and social sustainability. They are investing in alternative energy and other solutions to make the supply chain more environmentally friendly and are tracking their suppliers and identifying key vulnerabilities. A big part of this is an attempt to create fairer conditions for people who work in supply chains or are dependent on them.”

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    The move toward sustainable supply chain is being driven as much by people as by companies, whether they are playing the role of selective consumer or voting citizens. The consumer aspect is often overlooked, says Velázquez Martínez. “Consumers are the ones who move the supply chain. We are looking at how companies can provide transparency to involve customers in their sustainability strategy.” 

    Proposed solutions for sustainability are not always as effective as promised. Some fashion rental schemes fall into this category, says Velázquez Martínez. “There are many new rental companies that are trying to get more use out of clothes to offset the emissions associated with production. We recently researched the environmental impact of monthly subscription models where consumers pay a fee to receive clothes for a month before returning them, as well as peer-to-peer sharing models.” 

    The researchers found that while rental services generally have a lower carbon footprint than retail sales, hidden emissions from logistics played a surprisingly large role. “First, you need to deliver the clothes and pick them up, and there are high return rates,” says Velázquez Martínez. “When you factor in dry cleaning and packaging emissions, the rental models in some cases have a worse carbon footprint than buying new clothes.” Peer-to-peer sharing could be better, he adds, but that depends on how far the consumers travel to meet-up points. 

    Typically, says Velázquez Martínez, garment types that are frequently used are not well suited to rental models. “But for specialty clothes such as wedding dresses or prom dresses, it is better to rent.” 

    Waiting a few days to save the planet 

    Even before the pandemic, online retailing gained a second wind due to low-cost same- and next-day delivery options. While e-commerce may have its drawbacks as a contributor to social isolation and reduced competition, it has proven itself to be far more eco-friendly than brick-and-mortar shopping, not to mention a lot more convenient. Yet rapid deliveries are cutting into online-shopping’s carbon-cutting advantage.

    In 2019, MIT’s Sustainable Supply Chain Lab launched a Green Bottle project to study the rapid delivery phenomenon. The project has been “testing whether consumers would be willing to delay their e-commerce deliveries to reduce the environmental impact of fast shipping,” says Velázquez Martínez. “Many companies such as Walmart and Target have followed Amazon’s 2019 strategy of moving from two-day to same-day delivery. Instead of sending a fully loaded truck to a neighborhood every few days, they now send multiple trucks to that neighborhood every day, and there are more days when trucks are targeting each neighborhood. All this increases carbon emissions and makes it hard for shippers to consolidate. ”  

    Working with Coppel, one of Mexico’s largest retailers, the Green Button project inspired a related Consolidation Ecommerce Project that built a large-scale mathematical model to provide a strategy for consolidation. The model determined what delivery time window each neighborhood demands and then calculated the best day to deliver to each neighborhood to meet the desired window while minimizing carbon emissions. 

    No matter what mixture of delivery times was used, the consolidation model helped retailers schedule deliveries more efficiently. Yet, the biggest cuts in emissions emerged when customers were willing to wait several days.

    Play video

    “When we ran a month-long simulation comparing our model for four-to-five-day delivery with Coppel’s existing model for one- or two-day delivery, we saw savings in fuel consumption of over 50 percent on certain routes” says Velázquez Martínez. “This is huge compared to other strategies for squeezing more efficiency from the last-mile supply chain, such as routing optimization, where savings are close to 5 percent. The optimal solution depends on factors such as the capacity for consolidation, the frequency of delivery, the store capacity, and the impact on inbound operations.” 

    The researchers next set out to determine if customers could be persuaded to wait longer for deliveries. Considering that the price differential is low or nonexistent, this was a considerable challenge. Yet, the same day habit is only a few years old, and some consumers have come to realize they don’t always need rapid deliveries. “Some consumers who order by rapid delivery find they are too busy to open the packages right away,” says Velázquez Martínez.  

    Trees beat kilograms of CO2

    The researchers set out to find if consumers would be willing to sacrifice a bit of convenience if they knew they were helping to reduce climate change. The Green Button project tested different public outreach strategies. For one test group, they reported the carbon impact of delivery times in kilograms of carbon dioxide (CO2). Another group received the information expressed in terms of the energy required to recycle a certain amount of garbage. A third group learned about emissions in terms of the number of trees required to trap the carbon. “Explaining the impact in terms of trees led to almost 90 percent willing to wait another day or two,” says Velázquez Martínez. “This is compared to less than 40 percent for the group that received the data in kilograms of CO2.” 

    Another surprise was that there was no difference in response based on income, gender, or age. “Most studies of green consumers suggest they are predominantly high income, female, highly educated, or younger,” says Velázquez Martínez. “However, our results show that the differences were the same between low and high income, women and men, and younger and older people. We have shown that disclosing emissions transparently and making the consumer a part of the strategy can be a new opportunity for more consumer-driven logistics sustainability.” 

    The researchers are now developing similar models for business-to-business (B2B) e-commerce. “We found that B2B supply chain emissions are often high because many shipping companies require strict delivery windows,” says Velázquez Martínez.  

    The B2B models drill down to examine the Corporate Value Chain (Scope 3) emissions of suppliers. “Although some shipping companies are now asking their suppliers to review emissions, it is a challenge to create a transparent supply chain,” says Velázquez Martínez.  “Technological innovations have made it easier, starting with RFID [radio frequency identification], and then real-time GPS mapping and blockchain. But these technologies need to be more accessible and affordable, and we need more companies willing to use them.” 

    Some companies have been hesitant to dig too deeply into their supply chain, fearing they might uncover a scandal that might risk their reputation, says Velázquez Martínez. Other organizations are forced to look at the issue when nongovernmental organizations research sustainability issues such as social injustice in sweat shops and conflict mineral mines. 

    One challenge to building a transparent supply chain is that “in many companies, the sustainability teams are separate from the rest of the company,” says Velázquez Martínez. “Even if the CEOs receive information on sustainability issues, it often doesn’t filter down because the information does not belong to the planners or managers. We are pushing companies to not only account for sustainability factors in supply chain network design but also examine daily operations that affect sustainability. This is a big topic now: How can we translate sustainability information into something that everybody can understand and use?” 

    LIFT Lab lifts micro-retailers  

    In 2016, Velázquez Martínez launched the MIT GeneSys project to gain insights into micro and small enterprises (MSEs) in developing countries. The project released a GeneSys mobile app, which was used by more than 500 students throughout Latin America to collect data on more than 800 microfirms. In 2022, he launched the LIFT Lab, which focuses more specifically on studying and improving the supply chain for MSEs.  

    Worldwide, some 90 percent of companies have fewer than 10 employees. In Latin America and the Caribbean, companies with fewer than 50 employees represent 99 percent of all companies and 47 percent of employment. 

    Although MSEs represent much of the world’s economy, they are poorly understood, notes Velázquez Martínez. “Those tiny businesses are driving a lot of the economy and serve as important customers for the large companies working in developing countries. They range from small businesses down to people trying to get some money to eat by selling cakes or tacos through their windows.”  

    The MIT LIFT Lab researchers investigated whether MSE supply chain issues could help shed light on why many Latin American countries have been limited to marginal increases in gross domestic product. “Large companies from the developed world that are operating in Latin America, such as Unilever, Walmart, and Coca-Cola, have huge growth there, in some cases higher than they have in the developed world,” says Velázquez Martínez. “Yet, the countries are not developing as fast as we would expect.” 

    The LIFT Lab data showed that while the multinationals are thriving in Latin America, the local MSEs are decreasing in productivity. The study also found the trend has worsened with Covid-19.  

    The LIFT Lab’s first big project, which is sponsored by Mexican beverage and retail company FEMSA, is studying supply chains in Mexico. The study spans 200,000 micro-retailers and 300,000 consumers. In a collaboration with Tecnológico de Monterrey, hundreds of students are helping with a field study.  

    “We are looking at supply chain management and business capabilities and identifying the challenges to adoption of technology and digitalization,” says Velázquez Martínez. “We want to find the best ways for micro-firms to work with suppliers and consumers by identifying the consumers who access this market, as well as the products and services that can best help the micro-firms drive growth.” 

    Based on the earlier research by GeneSys, Velázquez Martínez has developed some hypotheses for potential improvements for micro-retailer supply chain, starting with payment terms. “We found that the micro-firms often get the worst purchasing deals. Owners without credit cards and with limited cash often buy in smaller amounts at much higher prices than retailers like Walmart. The big suppliers are squeezing them.” 

    While large retailers usually get 60 to 120 days to pay, micro-retailers “either pay at the moment of the transaction or in advance,” says Velázquez Martínez. “In a study of 500 micro-retailers in five countries in Latin America, we found the average payment time was minus seven days payment in advance. These terms reduce cash availability and often lead to bankruptcy.” 

    LIFT Lab is working with suppliers to persuade them to offer a minimum payment time of two weeks. “We can show the suppliers that the change in terms will let them move more product and increase sales,” says Velázquez Martínez. “Meanwhile, the micro-retailers gain higher profits and become more stable, even if they may pay a bit more.” 

    LIFT Lab is also looking at ways that micro-retailers can leverage smartphones for digitalization and planning. “Some of these companies are keeping records on napkins,” says Velázquez Martínez. “By using a cellphone, they can charge orders to suppliers and communicate with consumers. We are testing different dashboards for mobile apps to help with planning and financial performance. We are also recommending services the stores can provide, such as paying electricity or water bills. The idea is to build more capabilities and knowledge and increase business competencies for the supply chain that are tailored for micro-retailers.” 

    From a financial perspective, micro-retailers are not always the most efficient way to move products. Yet they also play an important role in building social cohesion within neighborhoods. By offering more services, the corner bodega can bring people together in ways that are impossible with e-commerce and big-box stores.  

    Whether the consumers are micro-firms buying from suppliers or e-commerce customers waiting for packages, “transparency is key to building a sustainable supply chain,” says Velázquez Martínez. “To change consumer habits, consumers need to be better educated on the impacts of their behaviors. With consumer-facing logistics, ‘The last shall be first, and the first last.’” More

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    in Security

    Professor Emeritus Richard Wurtman, influential figure in translational research, dies at 86

    Richard Wurtman, the Cecil H. Green Distinguished Professor Emeritus and a member of the MIT faculty for 44 years, died on Dec. 13. He was 86.

    Wurtman received an MD from Harvard Medical School in 1960 and trained at Massachusetts General Hospital before joining the laboratory of Nobel laureate Julius Axelrod at the National Institutes of Health in 1962. In 1967, MIT invited him to start a neurochemistry and neuropharmacology program in the Department of Nutrition and Food Science. In the early 1980s he joined the newly formed Department of Brain and Cognitive Sciences. Wurtman was also deeply involved in the National Institutes of Health-established Clinical Research Center at MIT, which he also directed for 25 years.

    His initial placement in Nutrition and Food Science was fortuitous, recalled Wurtman in a 2011 profile, because it “sensitized me to the fact that nutrients are chemicals the way drugs are chemicals. A compound like folic acid is a vitamin in foods, but when given alone in higher doses it becomes a drug that safeguards the developing nervous system.”

    Wurtman’s search for new biological properties and therapeutic uses of known molecules — hormones, nutrients, or existing pharmaceuticals — was highly fruitful. His research on the pineal gland, which started when he was a medical student, led to the discovery that melatonin, the hormone made by the gland, regulates sleep. 

    “Dick Wurtman was a pioneer in studying the role of neurotransmitters in the brain, and neuroendocrine regulation of normal and abnormal brain function,” says Newton Professor of Neuroscience Mriganka Sur, who served as head of the Department of Brain and Cognitive Sciences from 1997 to 2012. “His work on the impact of nutrition on neurotransmitters such as acetylcholine and on neuronal membrane synthesis laid the groundwork for later translational work on brain diseases such as Alzheimer’s disease.”

    Wurtman’s lab discovered that consuming carbohydrates increases tryptophan levels in the brain and consequently the production of the neurotransmitter serotonin. This led to a long collaboration with his wife Judith Wurtman, an MIT research affiliate, in which they found that carbohydrates were often consumed by individuals as a form of self-medication when they experienced changes in mood, such as late in the afternoon or when suffering from premenstrual syndrome (PMS). The Wurtmans’ research led to the development of Sarafem, the first drug for severe PMS, and a drink, PMS Escape, used for milder forms of this syndrome.

    To commercialize some of his findings, Wurtman founded Interneuron Pharmaceuticals in 1988; the company was renamed Indevus in 2002 and acquired by Endo Pharmaceuticals in 2009.

    Wurtman’s research advanced the idea that substrate availability, and not simply enzyme activity, can control metabolic processes in the brain. He discovered that the dietary availability of neurotransmitter precursors (e.g., acetylcholine, dopamine, and GABA) can increase their levels in the brain and modulate their metabolism. Moreover, he applied this concept to synaptic structural components such as brain phosphatides and found that dietary intake of three rate-limiting precursors — uridine, choline, and the omega-3 fatty acid DHA — led to increased brain phosphatide levels, increased dendritic spine density, and improved memory performance. These findings led to the development of Souvenaid, a specifically formulated multi-nutrient drink based on the three essential phosphatide precursors of Wurtman’s later research. It has been the subject of numerous clinical trials for Alzheimer’s disease, and, most recently, for age-related cognitive decline.

    “Dick Wurtman was a pioneer on studying how nutrients influence brain function,” says Li-Huei Tsai, Picower Professor of Neuroscience and director of The Picower Institute for Learning and Memory. “His nutrient clinical trial work and establishment of the MIT Clinical Research Center have been tremendously helpful for my own work on understanding how high doses of supplement choline could potentially help reduce certain Alzheimer’s risk, and our team’s development of clinical studies at MIT to test Alzheimer’s therapies.”

    “Dick’s legacy resides within the careers of hundreds of trainees and collaborators he launched or enhanced, the 1,000-plus published research articles, his numerous patent awards, and people who benefited from his therapeutic approaches,” says former postdoc Bertha Madras, now a professor of psychobiology at McLean Hospital and Harvard Medical School. “Yet, these quantitative metrics, legacies of research and mentoring, do not illustrate the charitable qualities of this remarkable man. I witnessed his deep intellect, boundless energy, enthusiasm, optimism, and generosity toward trainees, qualities that helped to sustain me during crests and troughs encountered in the adventures of a scientific career. Dr. Richard Wurtman was a creative, brilliant scientist, a mentor, a devoted husband to his beloved wife.”

    “Dick was an inspiration, a motivation, and a guide to all his students and colleagues in shaping thoughts to be precise and purposeful,” says Tony Nader PhD ’89, who did his doctoral research with Wurtman. “His rigorous scientific approach and the application of his findings have contributed to make life better. His legacy is huge.”

    Richard and Judith Wurtman have also made a lasting philanthropic impact at MIT. They endowed a professorship in the Department of Brain and Cognitive Sciences in honor of the late Institute Professor and provost Walter Rosenblith; the chair was held first by Ann Graybiel, who is now an Institute Professor; Nancy Kanwisher is the current Walter A. Rosenblith Professor of Cognitive Neuroscience. The Wurtmans have also been longtime supporters of MIT Hillel.

    Elazer R. Edelman, the Edward J. Poitras Professor in Medical Engineering and Science at MIT, professor of medicine at Harvard Medical School, and director of the MIT Institute for Medical Engineering and Science, recalls that Wurtman was also supportive of the Harvard-MIT Program in Health Sciences and Technology: “He changed our school and our world — he and Judith coupled immense charity with exceptional intellect and they made us all better for it.”

    Richard Wurtman is survived by his wife, Judith; daughter Rachael; son David and daughter-in-law Jean Chang; and grandchildren Dvora Toren, Yael Toren and Jacob Vider.  More

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    in Environment

    MIT community in 2022: A year in review

    In 2022, MIT returned to a bit of normalcy after the challenge of Covid-19 began to subside. The Institute prepared to bid farewell to its president and later announced his successor; announced five flagship projects in a new competition aimed at tackling climate’s greatest challenges; made new commitments toward ensuring support for diverse voices; and celebrated the reopening of a reimagined MIT Museum — as well as a Hollywood blockbuster featuring scenes from campus. Here are some of the top stories in the MIT community this year.

    Presidential transition

    In February, MIT President L. Rafael Reif announced that he planned to step down at the end of 2022. In more than 10 years as president, Reif guided MIT through a period of dynamic growth, greatly enhancing its global stature and magnetism. At the conclusion of his term at the end of this month, Reif will take a sabbatical, then return to the faculty of the Department of Electrical Engineering and Computer Science. In September, Reif expressed his gratitude to the MIT community at an Institute-wide dance celebration, and he was honored with a special MIT Dome lighting earlier this month.

    After an extensive presidential search, Sally Kornbluth, a cell biologist and the current provost of Duke University, was announced in October as MIT’s 18th president. Following an introduction to MIT that included a press conference, welcoming event, and community celebration, Kornbluth will assume the MIT presidency on Jan. 1, 2023.

    In other administrative transitions: Cynthia Barnhart was appointed provost after Martin Schmidt stepped down to become president of Rensselaer Polytechnic Institute; Sanjay Sarma stepped down as vice president for open learning after nine years in the role; professors Brent Ryan and Anne White were named associate provosts, while White was also named associate vice president for research administration; and Agustín Rayo was named dean of the School of Humanities, Arts, and Social Sciences.

    Climate Grand Challenges

    MIT announced five flagship projects in its first-ever Climate Grand Challenges competition. These multiyear projects focus on unraveling some of the toughest unsolved climate problems and bringing high-impact, science-based solutions to the world on an accelerated basis. Representing the most promising concepts to emerge from the two-year competition that yielded 27 finalist projects, the five flagship projects will receive additional funding and resources from MIT and others to develop their ideas and swiftly transform them into practical solutions at scale.

    CHIPS and Science Act

    President Reif and Vice President for Research Maria Zuber were among several MIT representatives to witness President Biden’s signing of the $52 billion “CHIPS and Science” bill into law in August. Reif helped shape aspects of the bill and was a vocal advocate for it among university and government officials, while Zuber served on two government science advisory boards during the bill’s gestation and consideration. Earlier in the year, MIT.nano hosted U.S. Secretary of Commerce Gina Raimondo, while MIT researchers released a key report on U.S. microelectronics research and manufacturing.

    MIT Morningside Academy for Design

    Supported by a $100 million founding gift, the MIT Morningside Academy for Design launched as a major interdisciplinary center that aims to build on the Institute’s leadership in design-focused education. Housed in the School of Architecture and Planning, the academy provides a hub that will encourage design work at MIT to grow and cross disciplines among engineering, science, management, computing, architecture, urban planning, and the arts.

    Reports of the Institute

    A number of key Institute reports and announcements were released in 2022. They include: an announcement of the future of gift acceptance for MIT: an announcement of priority MIT investments; a new MIT Values Statement; a renewed commitment to Indigenous scholarship and community; the Strategic Action Plan for Belonging, Achievement, and Composition; a report on MIT’s engagement with China; a report of the Working Group on Reimagining Public Safety at MIT; a report of the Indigenous Working Group; and a report of the Ad Hoc Committee on Arts, Culture, and DEI.

    Nobel Prizes

    MIT affiliates were well-represented among new and recent Nobel laureates who took part in the first in-person Nobel Prize ceremony since the start of the Covid-19 pandemic. MIT-affiliated winners for 2022 included Ben Bernanke PhD ’79, K. Barry Sharpless, and Carolyn Bertozzi. Winners in attendance from 2020 and 2021 included Professor Joshua Angrist, David Julius ’77, and Andrea Ghez ’87.

    New MIT Museum

    A reimagined MIT Museum opened this fall in a new 56,000-square-foot space in the heart of Cambridge’s Kendall Square. The museum invites visitors to explore the Institute’s innovations in science, technology, engineering, arts, and math — and to take part in that work with hands-on learning labs and maker spaces, interactive exhibits, and venues to discuss the impact of science and technology on society.

    “Wakanda Forever”

    In November, the Institute Office of Communications and the Division of Student Life hosted a special screening of Marvel Studios’ “Black Panther: Wakanda Forever.” The MIT campus had been used as a filming location in summer 2021, as one of the film’s characters, Riri Williams (also known as Ironheart), is portrayed as a student at the Institute.

    In-person Commencement returns

    After two years of online celebrations due to Covid-19, MIT Commencement returned to Killian Court at the end of May. World Trade Organization Director-General Ngozi Okonjo-Iweala MCP ’78, PhD ’81 delivered the Commencement address, while poet Kealoha Wong ’99 spoke at a special ceremony for the classes of 2020 and 2021.

    Students win distinguished fellowships

    As in previous years, MIT students continued to shine. This year, exceptional undergraduates were awarded Fulbright, Marshall, Mitchell, Rhodes, and Schwarzman scholarships.

    Remembering those we’ve lost

    Among MIT community members who died this year were Robert Balluffi, Louis Braida, Ashton Carter, Tom Eagar, Dick Eckaus, Octavian-Eugen Ganea, Peter Griffith, Patrick Hale, Frank Sidney Jones, Nonabah Lane, Leo Marx, Bruce Montgomery, Joel Moses, Brian Sousa Jr., Mohamed Magdi Taha, John Tirman, Richard Wurtman, and Markus Zahn.

    In case you missed it:

    Additional top community stories of 2022 included MIT students dominating the 82nd Putnam Mathematical Competition, an update on MIT’s reinstating the SAT/ACT requirement for admissions, a new mathematics program for Ukrainian students and refugees, a roundup of new books from MIT authors, the renaming of the MIT.nano building, an announcement of winners of this year’s MIT $100K Entrepreneurship Competition, the new MIT Wright Brothers Wind Tunnel, and MIT students winning the 45th International Collegiate Programming Contest for the first time in 44 years. More

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    in Security

    Food for thought, thought for food

    According to the Food and Agriculture Organization of the United Nations, approximately 3.1 billion people worldwide were unable to afford a healthy diet in 2020. Meanwhile, in 2021 close to 2.3 billion people were moderately or severely food insecure. Given the strong link between malnutrition and income disparity, the numbers paint a grim picture representing one of the grand challenges of our time.

    “I’m probably an idealist,” says MIT Research Scientist Christopher Mejía Argueta, “but I really believe that if we change our diets and think about ways to help others, we can make a difference — that’s my motivation.”

    Mejía Argueta is the founder and director of the MIT Food and Retail Operations Lab (FaROL). He has more than a decade of experience in supply chain management, optimization, and effective data-driven decision-making on pressing issues like the evolution of end consumers for retail and e-tail supply chains, food waste, and equitable access to nutrition.  

    Supply chain network designs typically focus on minimizing costs without considering the implications (e.g., cost) of changes in consumer behavior. Mejía Argueta and his colleagues at the FaROL, however, are working to understand and design optimal supply chains to create high-performance operations based on consumer choice. “Understanding the significant factors of consumer choice and analyzing their evolution over time becomes critical to designing forward-looking retail operations with data-driven and customer-centric supply chains, inventory management, and distribution systems,” explains Mejía Argueta. 

    Play video

    One of his recent projects examined the challenges of small retailers worldwide. These mom-and-pop outlets, or nanostores, account for 50 percent of the global market share and are the primary source of consumer packaged goods for people in urban areas. Worldwide there are nearly 50 million nanostores, each serving between 100-200 households in a community. In India alone, there are 14 million nanostores known as kiranas. And while these retailers are more prevalent in emerging markets, they play an important role in developed markets, particularly in under-resourced communities, and are frequently located in “food deserts,” where they are the only source of essential goods for the community.  

    These small retailers thrive thanks, partly, to their ability to offer the right combination of affordability and convenience while fostering trust with local customers, who often lack access to a supermarket or a grocery store. They often exist in fragmented, densely populated areas where infrastructure and public transportation services are poor and consumers have limited purchasing power. But nanostore shopkeepers and owners are intimately familiar with their customers and their consumption patterns, which means they can connect those consumption patterns or information to the larger supply chain. According to Mejía Argueta, when it comes to the future of retail, nanostores will be the cornerstones of growth in emerging economies. 

    But it’s a complicated scenario. Mom-and-pop shops don’t have the capacity to offer a broad range of products to their customers, and often, they lack access to nutritious food options. Logistically speaking, it is expensive to supply them, and the cost-to-serve (i.e., the logistics cost) is between 10 to 30 percent more expensive than other retailers. According to Mejía Argueta, this has a significant ripple effect, impacting education, productivity, and, eventually, the economic performance of an entire nation.  

    “The high fragmentation of nanostores causes substantial distribution inefficiencies, especially in congested megacities,” he says. “At my lab, we study how to make nanostores more efficient and effective by considering various commercial and logistics strategies while considering inherent technical challenges. We need to serve these small retailers better to help them survive and thrive, to provide a greater impact for underserved communities and the entire economic ecosystem.”

    Play video

    Mejía Argueta and his team recently collaborated with Tufts University and the City of Somerville, Massachusetts, to conduct research on food access models in underserved communities. The Somerville Project explored various interventions to supply fresh produce in food desert neighborhoods.

    “A lack of nutrition does not simply mean a lack of food,” Mejía Argueta says. “It can also be caused by an overabundance of unhealthy foods in a given market, which is particularly troublesome for U.S. cities where people in underserved communities don’t have access to healthy food options. We believe that one way to combat the problem of food deserts is to supply these areas with healthy food options affordably and create awareness programs.”  

    The collaborative project saw Mejía Argueta and his colleagues assessing the impact of several intervention schemes designed to empower the end consumer. For example, they implemented a low-cost grocery delivery model similar to Instacart as well as a ride sharing system to transport people from their homes to grocery stores and back. They also collaborated with a nonprofit organization, Partnership for a Healthier America, and began working with retailers to deliver “veggie boxes” in underserved communities. Models like these provide low-income people access to food while providing dignity of choice, Mejía Argueta explains.  

    When it comes to supply chain management research, sustainability and societal impact often fall by the wayside, but Mejía Argueta’s bottom-up approach shirks tradition. “We’re trying to build a community, employing a socially driven perspective because if you work with the community, you gain their trust. If you want to make something sustainable in the long term, people need to trust in these solutions and engage with the ecosystem as a whole.”  

    And to achieve real-world impact, collaboration is key. Mejía Argueta says that government has an important role to play, developing policy to connect the models he and his colleagues develop in academia to societal challenges. Meanwhile, he believes startups and entrepreneurs can function as bridge-builders to link the flows of information, the flows of goods and cash, and even knowledge and security in an ecosystem that suffers from fragmentation and siloed thinking among stakeholders.

    Finally, Mejía Argueta reflects on the role of corporations and his belief that the MIT Industrial Liaison Program is essential to getting his research to the frontline of business challenges. “The Industrial Liaison Program does a fantastic job of connecting our research to real-world scenarios,” he says. “It creates opportunities for us to have meaningful interactions with corporates for real-world impact. I believe strongly in the MIT motto ‘mens et manus,’ and ILP helps drive our research into practice.” More

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    in Security

    Microparticles could help prevent vitamin A deficiency

    Vitamin A deficiency is the world’s leading cause of childhood blindness, and in severe cases, it can be fatal. About one-third of the global population of preschool-aged children suffer from this vitamin deficiency, which is most prevalent in sub-Saharan Africa and South Asia.

    MIT researchers have now developed a new way to fortify foods with vitamin A, which they hope could help to improve the health of millions of people around the world. In a new study, they showed that encapsulating vitamin A in a protective polymer prevents the nutrient from being broken down during cooking or storage.

    “Vitamin A is a very important micronutrient, but it’s an unstable molecule,” says Ana Jaklenec, a research scientist at MIT’s Koch Institute for Integrative Cancer Research. “We wanted to see if our encapsulated vitamin A could fortify a food vehicle like bouillon cubes or flour, throughout storage and cooking, and whether the vitamin A could remain biologically active and be absorbed.”

    In a small clinical trial, the researchers showed that when people ate bread fortified with encapsulated vitamin A, the bioavailability of the nutrient was similar to when they consumed vitamin A on its own. The technology has been licensed to two companies that hope to develop it for use in food products.

    “This is a study that our team is really excited about because it shows that everything we did in test tubes and animals works safely and effectively in humans,” says Robert Langer, the David H. Koch Institute Professor at MIT and a member of the Koch Institute. “We hope this opens the door for someday helping millions, if not billions, of people in the developing world.”

    Jaklenec and Langer are the senior authors of the new study, which appears this week in the Proceedings of the National Academy of Sciences. The paper’s lead author is former MIT postdoc Wen Tang, who is now an associate professor at South China University of Technology.

    Nutrient stability

    Vitamin A is critical not only for vision but also the functioning of the immune system and organs such as the heart and lungs. Efforts to add vitamin A to bread or other foods such as bouillon cubes, which are commonly consumed in West African countries, have been largely unsuccessful because the vitamin breaks down during storage or cooking.

    In a 2019 study, the MIT team showed that they could use a polymer called BMC to encapsulate nutrients, including iron, vitamin A, and several others. They showed that this protective coating improved the shelf life of the nutrients, and that people who consumed bread fortified with encapsulated iron were able to absorb the iron.

    BMC is classified by the FDA as “generally regarded as safe,” and is already used in coatings for drugs and dietary supplements. In the new study, the researchers focused on using this polymer to encapsulate vitamin A, a nutrient that is very sensitive to temperature and ultraviolet light.

    Using an industrial process known as a spinning disc process, the researchers mixed vitamin A with the polymer to form particles 100 to 200 microns in diameter. They also coated the particles with starch, which prevents them from sticking to each other.

    The researchers found that vitamin A encapsulated in the polymer particles were more resistant to degradation by intense light, high temperatures, or boiling water. Under those conditions, much more vitamin A remained active than when the vitamin A was free or when it was delivered in a form called VitA 250, which is currently the most stable form of vitamin A used for food fortification.

    The researchers also showed that the encapsulated particles could be easily incorporated into flour or bouillon cubes. To test how well they would survive long-term storage, the researchers exposed the cubes to harsh conditions, as recommended by the World Health Organization: 40 degrees Celsius (104 degrees Fahrenheit) and 75 percent humidity. Under those conditions, the encapsulated vitamin A was much more stable than other forms of vitamin A. 

    “The enhanced stability of vitamin A with our technology can ensure that the vitamin A-fortified food does provide the recommended daily uptake of vitamin A, even after long-term storage in a hot humidified environment, and cooking processes such as boiling or baking,” Tang says. “People who are suffering from vitamin A deficiency and want to get vitamin A through fortified food will benefit, without changing their daily routines, and without wondering how much vitamin A is still in the food.”

    Vitamin absorption

    When the researchers cooked their encapsulated particles and then fed them to animals, they found that 30 percent of the vitamin A was absorbed, the same as free uncooked vitamin A, compared to about 3 percent of free vitamin A that had been cooked.

    Working with Biofortis, a company that does dietary clinical testing, the researchers then evaluated how well vitamin A was absorbed in people who ate foods fortified with the particles. For this study, the researchers incorporated the particles into bread, then measured vitamin A levels in the blood over a 24-hour period after the bread was consumed. They found that when vitamin A was encapsulated in the BMC polymer, it was absorbed from the food at levels comparable to free vitamin A, indicating that it is readily released in bioactive form.

    Two companies have licensed the technology and are focusing on developing products fortified with vitamin A and other nutrients. A benefit corporation called Particles for Humanity, funded by the Bill and Melinda Gates Foundation, is working with partners in Africa to incorporate this technology into existing fortification efforts. Another company called VitaKey, founded by Jaklenec, Langer, and others, is working on using this approach to add nutrients to a variety of foods and beverages.

    The research was funded by the Bill and Melinda Gates Foundation. Other authors of the paper include Jia Zhuang, Aaron Anselmo, Xian Xu, Aranda Duan, Ruojie Zhang, James Sugarman, Yingying Zeng, Evan Rosenberg, Tyler Graf, Kevin McHugh, Stephany Tzeng, Adam Behrens, Lisa Freed, Lihong Jing, Surangi Jayawardena, Shelley Weinstock, Xiao Le, Christopher Sears, James Oxley, John Daristotle, and Joe Collins. More