Security

Subterms

    More stories

    • 125 Shares169 Views

      in Security

      System tracks movement of food through global humanitarian supply chain

      by

      Although more than enough food is produced to feed everyone in the world, as many as 828 million people face hunger today. Poverty, social inequity, climate change, natural disasters, and political conflicts all contribute to inhibiting access to food. For decades, the U.S. Agency for International Development (USAID) Bureau for Humanitarian Assistance (BHA) has been a leader in global food assistance, supplying millions of metric tons of food to recipients worldwide. Alleviating hunger — and the conflict and instability hunger causes — is critical to U.S. national security.

      But BHA is only one player within a large, complex supply chain in which food gets handed off between more than 100 partner organizations before reaching its final destination. Traditionally, the movement of food through the supply chain has been a black-box operation, with stakeholders largely out of the loop about what happens to the food once it leaves their custody. This lack of direct visibility into operations is due to siloed data repositories, insufficient data sharing among stakeholders, and different data formats that operators must manually sort through and standardize. As a result, accurate, real-time information — such as where food shipments are at any given time, which shipments are affected by delays or food recalls, and when shipments have arrived at their final destination — is lacking. A centralized system capable of tracing food along its entire journey, from manufacture through delivery, would enable a more effective humanitarian response to food-aid needs.

      In 2020, a team from MIT Lincoln Laboratory began engaging with BHA to create an intelligent dashboard for their supply-chain operations. This dashboard brings together the expansive food-aid datasets from BHA’s existing systems into a single platform, with tools for visualizing and analyzing the data. When the team started developing the dashboard, they quickly realized the need for considerably more data than BHA had access to.

      “That’s where traceability comes in, with each handoff partner contributing key pieces of information as food moves through the supply chain,” explains Megan Richardson, a researcher in the laboratory’s Humanitarian Assistance and Disaster Relief Systems Group.

      Richardson and the rest of the team have been working with BHA and their partners to scope, build, and implement such an end-to-end traceability system. This system consists of serialized, unique identifiers (IDs) — akin to fingerprints — that are assigned to individual food items at the time they are produced. These individual IDs remain linked to items as they are aggregated along the supply chain, first domestically and then internationally. For example, individually tagged cans of vegetable oil get packaged into cartons; cartons are placed onto pallets and transported via railway and truck to warehouses; pallets are loaded onto shipping containers at U.S. ports; and pallets are unloaded and cartons are unpackaged overseas.

      With a trace

      Today, visibility at the single-item level doesn’t exist. Most suppliers mark pallets with a lot number (a lot is a batch of items produced in the same run), but this is for internal purposes (i.e., to track issues stemming back to their production supply, like over-enriched ingredients or machinery malfunction), not data sharing. So, organizations know which supplier lot a pallet and carton are associated with, but they can’t track the unique history of an individual carton or item within that pallet. As the lots move further downstream toward their final destination, they are often mixed with lots from other productions, and possibly other commodity types altogether, because of space constraints. On the international side, such mixing and the lack of granularity make it difficult to quickly pull commodities out of the supply chain if food safety concerns arise. Current response times can span several months.

      “Commodities are grouped differently at different stages of the supply chain, so it is logical to track them in those groupings where needed,” Richardson says. “Our item-level granularity serves as a form of Rosetta Stone to enable stakeholders to efficiently communicate throughout these stages. We’re trying to enable a way to track not only the movement of commodities, including through their lot information, but also any problems arising independent of lot, like exposure to high humidity levels in a warehouse. Right now, we have no way to associate commodities with histories that may have resulted in an issue.”

      “You can now track your checked luggage across the world and the fish on your dinner plate,” adds Brice MacLaren, also a researcher in the laboratory’s Humanitarian Assistance and Disaster Relief Systems Group. “So, this technology isn’t new, but it’s new to BHA as they evolve their methodology for commodity tracing. The traceability system needs to be versatile, working across a wide variety of operators who take custody of the commodity along the supply chain and fitting into their existing best practices.”

      As food products make their way through the supply chain, operators at each receiving point would be able to scan these IDs via a Lincoln Laboratory-developed mobile application (app) to indicate a product’s current location and transaction status — for example, that it is en route on a particular shipping container or stored in a certain warehouse. This information would get uploaded to a secure traceability server. By scanning a product, operators would also see its history up until that point.   

      Hitting the mark

      At the laboratory, the team tested the feasibility of their traceability technology, exploring different ways to mark and scan items. In their testing, they considered barcodes and radio-frequency identification (RFID) tags and handheld and fixed scanners. Their analysis revealed 2D barcodes (specifically data matrices) and smartphone-based scanners were the most feasible options in terms of how the technology works and how it fits into existing operations and infrastructure.

      “We needed to come up with a solution that would be practical and sustainable in the field,” MacLaren says. “While scanners can automatically read any RFID tags in close proximity as someone is walking by, they can’t discriminate exactly where the tags are coming from. RFID is expensive, and it’s hard to read commodities in bulk. On the other hand, a phone can scan a barcode on a particular box and tell you that code goes with that box. The challenge then becomes figuring out how to present the codes for people to easily scan without significantly interrupting their usual processes for handling and moving commodities.” 

      As the team learned from partner representatives in Kenya and Djibouti, offloading at the ports is a chaotic, fast operation. At manual warehouses, porters fling bags over their shoulders or stack cartons atop their heads any which way they can and run them to a drop point; at bagging terminals, commodities come down a conveyor belt and land this way or that way. With this variability comes several questions: How many barcodes do you need on an item? Where should they be placed? What size should they be? What will they cost? The laboratory team is considering these questions, keeping in mind that the answers will vary depending on the type of commodity; vegetable oil cartons will have different specifications than, say, 50-kilogram bags of wheat or peas.

      Leaving a mark

      Leveraging results from their testing and insights from international partners, the team has been running a traceability pilot evaluating how their proposed system meshes with real-world domestic and international operations. The current pilot features a domestic component in Houston, Texas, and an international component in Ethiopia, and focuses on tracking individual cartons of vegetable oil and identifying damaged cans. The Ethiopian team with Catholic Relief Services recently received a container filled with pallets of uniquely barcoded cartons of vegetable oil cans (in the next pilot, the cans will be barcoded, too). They are now scanning items and collecting data on product damage by using smartphones with the laboratory-developed mobile traceability app on which they were trained. 

      “The partners in Ethiopia are comparing a couple lid types to determine whether some are more resilient than others,” Richardson says. “With the app — which is designed to scan commodities, collect transaction data, and keep history — the partners can take pictures of damaged cans and see if a trend with the lid type emerges.”

      Next, the team will run a series of pilots with the World Food Program (WFP), the world’s largest humanitarian organization. The first pilot will focus on data connectivity and interoperability, and the team will engage with suppliers to directly print barcodes on individual commodities instead of applying barcode labels to packaging, as they did in the initial feasibility testing. The WFP will provide input on which of their operations are best suited for testing the traceability system, considering factors like the network bandwidth of WFP staff and local partners, the commodity types being distributed, and the country context for scanning. The BHA will likely also prioritize locations for system testing.

      “Our goal is to provide an infrastructure to enable as close to real-time data exchange as possible between all parties, given intermittent power and connectivity in these environments,” MacLaren says.

      In subsequent pilots, the team will try to integrate their approach with existing systems that partners rely on for tracking procurements, inventory, and movement of commodities under their custody so that this information is automatically pushed to the traceability server. The team also hopes to add a capability for real-time alerting of statuses, like the departure and arrival of commodities at a port or the exposure of unclaimed commodities to the elements. Real-time alerts would enable stakeholders to more efficiently respond to food-safety events. Currently, partners are forced to take a conservative approach, pulling out more commodities from the supply chain than are actually suspect, to reduce risk of harm. Both BHA and WHP are interested in testing out a food-safety event during one of the pilots to see how the traceability system works in enabling rapid communication response.

      To implement this technology at scale will require some standardization for marking different commodity types as well as give and take among the partners on best practices for handling commodities. It will also require an understanding of country regulations and partner interactions with subcontractors, government entities, and other stakeholders.

      “Within several years, I think it’s possible for BHA to use our system to mark and trace all their food procured in the United States and sent internationally,” MacLaren says.

      Once collected, the trove of traceability data could be harnessed for other purposes, among them analyzing historical trends, predicting future demand, and assessing the carbon footprint of commodity transport. In the future, a similar traceability system could scale for nonfood items, including medical supplies distributed to disaster victims, resources like generators and water trucks localized in emergency-response scenarios, and vaccines administered during pandemics. Several groups at the laboratory are also interested in such a system to track items such as tools deployed in space or equipment people carry through different operational environments.

      “When we first started this program, colleagues were asking why the laboratory was involved in simple tasks like making a dashboard, marking items with barcodes, and using hand scanners,” MacLaren says. “Our impact here isn’t about the technology; it’s about providing a strategy for coordinated food-aid response and successfully implementing that strategy. Most importantly, it’s about people getting fed.” More

    • 88 Shares129 Views

      in Security

      Exploring the links between diet and cancer

      by

      Every three to five days, all of the cells lining the human intestine are replaced. That constant replenishment of cells helps the intestinal lining withstand the damage caused by food passing through the digestive tract.

      This rapid turnover of cells relies on intestinal stem cells, which give rise to all of the other types of cells found in the intestine. Recent research has shown that those stem cells are heavily influenced by diet, which can help keep them healthy or stimulate them to become cancerous.

      “Low-calorie diets such as fasting and caloric restriction can have antiaging effects and antitumor effects, and we want to understand why that is. On the other hand, diets that lead to obesity can promote diseases of aging, such as cancer,” says Omer Yilmaz, the Eisen and Chang Career Development Associate Professor of Biology at MIT.

      For the past decade, Yilmaz has been studying how different diets and environmental conditions affect intestinal stem cells, and how those factors can increase the risk of cancer and other diseases. This work could help researchers develop new ways to improve gastrointestinal health, either through dietary interventions or drugs that mimic the beneficial effects of certain diets, he says. 

      “Our findings have raised the possibility that fasting interventions, or small molecules that mimic the effects of fasting, might have a role in improving intestinal regeneration,” says Yilmaz, who is also a member of MIT’s Koch Institute for Integrative Cancer Research.

      A clinical approach

      Yilmaz’s interest in disease and medicine arose at an early age. His father practiced internal medicine, and Yilmaz spent a great deal of time at his father’s office after school, or tagging along at the hospital where his father saw patients.

      “I was very interested in medicines and how medicines were used to treat diseases,” Yilmaz recalls. “He’d ask me questions, and many times I wouldn’t know the answer, but he would encourage me to figure out the answers to his questions. That really stimulated my interest in biology and in wanting to become a doctor.”

      Knowing that he wanted to go into medicine, Yilmaz applied and was accepted to an eight-year, combined bachelor’s and MD program at the University of Michigan. As an undergraduate, this gave him the freedom to explore areas of interest without worrying about applying to medical school. While majoring in biochemistry and physics, he did undergraduate research in the field of protein folding.

      During his first year of medical school, Yilmaz realized that he missed doing research, so he decided to apply to the MD/PhD program at the University of Michigan. For his PhD research, he studied blood-forming stem cells and identified new markers that allowed such cells to be more easily isolated from the bone marrow.

      “This was important because there’s a lot of interest in understanding what makes a stem cell a stem cell, and how much of it is an internal program versus signals from the microenvironment,” Yilmaz says.

      After finishing his PhD and MD, he thought about going straight into research and skipping a medical residency, but ended up doing a residency in pathology at Massachusetts General Hospital. During that time, he decided to switch his research focus from blood-forming stem cells to stem cells found in the gastrointestinal tract.

      “The GI tract seemed very interesting because in contrast to the bone marrow, we knew very little about the identity of GI stem cells,” Yilmaz says. “I knew that once GI stem cells were identified, there’d be a lot of interesting questions about how they respond to diet and how they respond to other environmental stimuli.”

      Dietary questions

      To delve into those questions, Yilmaz did postdoctoral research at the Whitehead Institute, where he began investigating the connections between stem cells, metabolism, diet, and cancer.

      Because intestinal stem cells are so long-lived, they are more likely to accumulate genetic mutations that make them susceptible to becoming cancerous. At the Whitehead Institute, Yilmaz began studying how different diets might influence this vulnerability to cancer, a topic that he carried into his lab at MIT when he joined the faculty in 2014.

      One question his lab has been exploring is why low-calorie diets often have protective effects, including a boost in longevity — a phenomenon that has been seen in many studies in animals and humans.

      In a 2018 study, his lab found that a 24-hour fast dramatically improves stem cells’ ability to regenerate. This effect was seen in both young and aged mice, suggesting that even in old age, fasting or drugs that mimic the effects of fasting could have a beneficial effect.

      On the flip side, Yilmaz is also interested in why a high-fat diet appears to promote the development of cancer, especially colorectal cancer. In a 2016 study, he found that when mice consume a high-fat diet, it triggers a significant increase in the number of intestinal stem cells. Also, some non-stem-cell populations begin to resemble stem cells in their behavior. “The upshot of these changes is that both stem cells and non-stem-cells can give rise to tumors in a high-fat diet state,” Yilmaz says.

      To help with these studies, Yilmaz’s lab has developed a way to use mouse or human intestinal stem cells to generate miniature intestines or colons in cell culture. These “organoids” can then be exposed to different nutrients in a very controlled setting, allowing researchers to analyze how different diets affect the system.

      Recently, his lab adapted the system to allow them to expand their studies to include the role of immune cells, fibroblasts, and other supportive cells found in the microenvironment of stem cells. “It would be remiss of us to focus on just one cell type,” Yilmaz says. “We’re looking at how these different dietary interventions impact the entire stem cell neighborhood.”

      While Yilmaz spends most of his time running his lab at MIT, he also devotes six to eight weeks per year to his work at MGH, where he is an associate pathologist focusing on gastrointestinal pathology.

      “I enjoy my clinical work, and it always reminds me about the importance of the research we do,” he says. “Seeing colon cancer and other GI cancers under the microscope, and seeing their complexity, reminds me of the importance of our mission to figure out how we can prevent these cancers from forming.” More

    • 75 Shares169 Views

      in Security

      Ingestible “electroceutical” capsule stimulates hunger-regulating hormone

      by

      Hormones released by the stomach, such as ghrelin, play a key role in stimulating appetite. These hormones are produced by endocrine cells that are part of the enteric nervous system, which controls hunger, nausea, and feelings of fullness.

      MIT engineers have now shown that they can stimulate these endocrine cells to produce ghrelin, using an ingestible capsule that delivers an electrical current to the cells. This approach could prove useful for treating diseases that involve nausea or loss of appetite, such as cachexia (loss of body mass that can occur in patients with cancer or other chronic diseases).

      In tests in animals, the researchers showed that this “electroceutical” capsule could significantly boost ghrelin production in the stomach. They believe this approach could also be adapted to deliver electrical stimulation to other parts of the GI tract.

      “This study helps establish electrical stimulation by ingestible electroceuticals as a mode of triggering hormone release via the GI tract,” says Giovanni Traverso, an associate professor of mechanical engineering at MIT, a gastroenterologist at Brigham and Women’s Hospital, and the senior author of the study. “We show one example of how we’re able to engage with the stomach mucosa and release hormones, and we anticipate that this could be used in other sites in the GI tract that we haven’t explored here.”

      Khalil Ramadi SM ’16, PhD ’19, a graduate of the Department of Mechanical Engineering and the Harvard-MIT Program in Health Sciences and Technology who is now an assistant professor of bioengineering at the New York University (NYU) Tandon School of Engineering and the director of the Laboratory for Advanced Neuroengineering and Translational Medicine at NYU Abu Dhabi, and James McRae, an MIT graduate student, are the lead authors of the paper, which appears today in Science Robotics.

      Electrical stimulation

      The enteric nervous system controls all aspects of digestion, including the movement of food through the GI tract. Some patients with gastroparesis, a disorder of the stomach nerves that leads to very slow movement of food, have shown symptomatic improvement after electrical stimulation generated by a pacemaker-like device that can be surgically implanted in the stomach.

      Doctors had theorized that the electrical stimulation would provoke the stomach into contracting, which would help push food along. However, it was later found that while the treatment does help patients feel better, it affected motility to a lesser degree. The MIT team hypothesized that the electrical stimulation of the stomach might be leading to the release of ghrelin, which is known to promote hunger and reduce feelings of nausea.

      To test that hypothesis, the researchers used an electrical probe to deliver electrical stimulation in the stomachs of animals. They found that after 20 minutes of stimulation, ghrelin levels in the bloodstream were considerably elevated. They also found that electrical stimulation did not lead to any significant inflammation or other adverse effects.

      Once they established that electrical stimulation was provoking ghrelin release, the researchers set out to see if they could achieve the same thing using a device that could be swallowed and temporarily reside in the stomach. One of the main challenges in designing such a device is ensuring that the electrodes on the capsule can contact the stomach tissue, which are coated with fluid. 

      Play video

      To create a drier surface that electrodes can interact with, the researchers gave their capsule a grooved surface that wicks fluid away from the electrodes. The surface they designed is inspired by the skin of the Australian thorny devil lizard, which uses ridged scales to collect water. When the lizard touches water with any part of its skin, water is transported by capillary action along the channels to the lizard’s mouth.

      “We were inspired by that to incorporate surface textures and patterns onto the outside of this capsule,” McRae says. “That surface can manage the fluid that could potentially prevent the electrodes from touching the tissue in the stomach, so it can reliably deliver electrical stimulation.”

      The capsule surface consists of grooves with a hydrophilic coating. These grooves function as channels that draw fluid away from the stomach tissue. Inside the device are battery-powered electronics that produce an electric current that flows across electrodes on the surface of the capsule. In the prototype used in this study, the current runs constantly, but future versions could be designed so that the current can be wirelessly turned on and off, according to the researchers.

      Hormone boost

      The researchers tested their capsule by administering it into the stomachs of large animals, and they found that the capsule produced a substantial spike in ghrelin levels in the bloodstream.

      “As far as we know, this is the first example of using electrical stimuli through an ingestible device to increase endogenous levels of hormones in the body, like ghrelin. And so, it has this effect of utilizing the body’s own systems rather than introducing external agents,” Ramadi says.

      The researchers found that in order for this stimulation to work, the vagus nerve, which controls digestion, must be intact. They theorize that the electrical pulses transmit to the brain via the vagus nerve, which then stimulates endocrine cells in the stomach to produce ghrelin.

      Traverso’s lab now plans to explore using this approach in other parts of the GI tract, and the researchers hope to test the device in human patients within the next three years. If developed for use in human patients, this type of treatment could potentially replace or complement some of the existing drugs used to prevent nausea and stimulate appetite in people with cachexia or anorexia, the researchers say.

      “It’s a relatively simple device, so we believe it’s something that we can get into humans on a relatively quick time scale,” Traverso says.

      The research was funded by the Koch Institute Support (core) Grant from the National Cancer Institute, the National Institute for Diabetes and Digestive and Kidney Diseases, the Division of Engineering at New York University Abu Dhabi, a National Science Foundation graduate research fellowship, Novo Nordisk, and the Department of Mechanical Engineering at MIT. More

    • 138 Shares199 Views

      in Security

      Scientists uncover the amazing way sandgrouse hold water in their feathers

      by

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

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

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

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

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

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

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

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

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

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

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

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

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

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

    • 75 Shares109 Views

      in Security

      Tackling counterfeit seeds with “unclonable” labels

      by

      Average crop yields in Africa are consistently far below those expected, and one significant reason is the prevalence of counterfeit seeds whose germination rates are far lower than those of the genuine ones. The World Bank estimates that as much as half of all seeds sold in some African countries are fake, which could help to account for crop production that is far below potential.

      There have been many attempts to prevent this counterfeiting through tracking labels, but none have proved effective; among other issues, such labels have been vulnerable to hacking because of the deterministic nature of their encoding systems. But now, a team of MIT researchers has come up with a kind of tiny, biodegradable tag that can be applied directly to the seeds themselves, and that provides a unique randomly created code that cannot be duplicated.

      The new system, which uses minuscule dots of silk-based material, each containing a unique combination of different chemical signatures, is described today in the journal Science Advances in a paper by MIT’s dean of engineering Anantha Chandrakasan, professor of civil and environmental engineering Benedetto Marelli, postdoc Hui Sun, and graduate student Saurav Maji.

      The problem of counterfeiting is an enormous one globally, the researchers point out, affecting everything from drugs to luxury goods, and many different systems have been developed to try to combat this. But there has been less attention to the problem in the area of agriculture, even though the consequences can be severe. In sub-Saharan Africa, for example, the World Bank estimates that counterfeit seeds are a significant factor in crop yields that average less than one-fifth of the potential for maize, and less than one-third for rice.

      Marelli explains that a key to the new system is creating a randomly-produced physical object whose exact composition is virtually impossible to duplicate. The labels they create “leverage randomness and uncertainty in the process of application, to generate unique signature features that can be read, and that cannot be replicated,” he says.

      What they’re dealing with, Sun adds, “is the very old job of trying, basically, not to get your stuff stolen. And you can try as much as you can, but eventually somebody is always smart enough to figure out how to do it, so nothing is really unbreakable. But the idea is, it’s almost impossible, if not impossible, to replicate it, or it takes so much effort that it’s not worth it anymore.”

      The idea of an “unclonable” code was originally developed as a way of protecting the authenticity of computer chips, explains Chandrakasan, who is the Vannevar Bush Professor of Electrical Engineering and Computer Science. “In integrated circuits, individual transistors have slightly different properties coined device variations,” he explains, “and you could then use that variability and combine that variability with higher-level circuits to create a unique ID for the device. And once you have that, then you can use that unique ID as a part of a security protocol. Something like transistor variability is hard to replicate from device to device, so that’s what gives it its uniqueness, versus storing a particular fixed ID.” The concept is based on what are known as physically unclonable functions, or PUFs.

      The team decided to try to apply that PUF principle to the problem of fake seeds, and the use of silk proteins was a natural choice because the material is not only harmless to the environment but also classified by the Food and Drug Administration in the “generally recognized as safe” category, so it requires no special approval for use on food products.

      “You could coat it on top of seeds,” Maji says, “and if you synthesize silk in a certain way, it will also have natural random variations. So that’s the idea, that every seed or every bag could have a unique signature.”

      Developing effective secure system solutions has long been one of Chandrakasan’s specialties, while Marelli has spent many years developing systems for applying silk coatings to a variety of fruits, vegetables, and seeds, so their collaboration was a natural for developing such a silk-based coding system toward enhanced security.

      “The challenge was what type of form factor to give to silk,” Sun says, “so that it can be fabricated very easily.” They developed a simple drop-casting approach that produces tags that are less than one-tenth of an inch in diameter. The second challenge was to develop “a way where we can read the uniqueness, in also a very high throughput and easy way.”

      For the unique silk-based codes, Marelli says, “eventually we found a way to add a color to these microparticles so that they assemble in random structures.” The resulting unique patterns can be read out not only by a spectrograph or a portable microscope, but even by an ordinary cellphone camera with a macro lens. This image can be processed locally to generate the PUF code and then sent to the cloud and compared with a secure database to ensure the authenticity of the product. “It’s random so that people cannot easily replicate it,” says Sun. “People cannot predict it without measuring it.”

      And the number of possible permutations that could result from the way they mix four basic types of colored silk nanoparticles is astronomical. “We were able to show that with a minimal amount of silk, we were able to generate 128 random bits of security,” Maji says. “So this gives rise to 2 to the power 128 possible combinations, which is extremely difficult to crack given the computational capabilities of the state-of-the-art computing systems.”

      Marelli says that “for us, it’s a good test bed in order to think out-of-the-box, and how we can have a path that somehow is more democratic.” In this case, that means “something that you can literally read with your phone, and you can fabricate by simply drop casting a solution, without using any advanced manufacturing technique, without going in a clean room.”

      Some additional work will be needed to make this a practical commercial product, Chandrakasan says. “There will have to be a development for at-scale reading” via smartphones. “So, that’s clearly a future opportunity.” But the principle now shows a clear path to the day when “a farmer could at least, maybe not every seed, but could maybe take some random seeds in a particular batch and verify them,” he says.

      The research was partially supported by the U.S. Office of Naval research and the National Science Foundation, Analog Devices Inc., an EECS Mathworks fellowship, and a Paul M. Cook Career Development Professorship. More

    • 75 Shares119 Views

      in Security

      Titanic robots make farming more sustainable

      by

      There’s a lot riding on farmers’ ability to fight weeds, which can strangle crops and destroy yields. To protect crops, farmers have two options: They can spray herbicides that pollute the environment and harm human health, or they can hire more workers.

      Unfortunately, both choices are becoming less tenable. Herbicide resistance is a growing problem in crops around the world, while widespread labor shortages have hit the agricultural sector particularly hard.

      Now the startup FarmWise, co-founded by Sebastien Boyer SM ’16, is giving farmers a third option. The company has developed autonomous weeding robots that use artificial intelligence to cut out weeds while leaving crops untouched.

      The company’s first robot, fittingly called the Titan — picture a large tractor that makes use of a trailer in lieu of a driver’s seat — uses machine vision to distinguish weeds from crops including leafy greens, cauliflower, artichokes, and tomatoes while snipping weeds with sub-inch precision.

      About 15 Titans have been roaming the fields of 30 large farms in California and Arizona for the last few years, providing weeding as a service while being directed by an iPad. Last month, the company unveiled its newest robot, Vulcan, which is more lightweight and pulled by a tractor.

      “We have growing population, and we can’t expand the land or water we have, so we need to drastically increase the efficiency of the farming industry,” Boyer says. “I think AI and data are going to be major players in that journey.”

      Finding a road to impact

      Boyer came to MIT in 2014 and earned masters’ degrees in technology and policy as well as electrical engineering and computer science over the next two years.

      “What stood out is the passion that my classmates had for what they did — the drive and passion people had to change the world,” Boyer says.

      As part of his graduate work, Boyer researched machine learning and machine vision techniques, and he soon began exploring ways to apply those technologies to environmental problems. He received a small amount of funding from MIT Sandbox to further develop the idea.

      “That helped me make the decision to not take a real job,” Boyer recalls.

      Following graduation, he and FarmWise co-founder Thomas Palomares, a graduate of Stanford University whom Boyer met in his home country of France, began going to farmers’ markets, introducing themselves to small farmers and asking for tours of their farms. About one in three farmers were happy to show them around. From there they’d ask for referrals to larger farmers and service providers in the industry.

      “We realized agriculture is a large contributor of both emissions and, more broadly, to the negative impact of human activities on the environment,” Boyer says. “It also hasn’t been as disrupted by software, cloud computing, AI, and robotics as other industries. That combination really excites us.”

      Through their conversations, the founders learned herbicides are becoming less effective as weeds develop genetic resistance. The only alternative is to hire more workers, which itself was becoming more difficult for farmers.

      “Labor is extremely tight,” says Boyer, adding that bending over and weeding for 10 hours a day is one of the hardest jobs out there. “The labor supply is shrinking if not collapsing in the U.S., and it’s a worldwide trend. That has real environmental implications because of the tradeoff [between labor and herbicides].”

      The problem is especially acute for farmers of specialty crops, including many fruits, vegetables, and nuts, which grow on smaller farms than corn and soybean and each require slightly different growing practices, limiting the effectiveness of many technical and chemical solutions.

      “We don’t harvest corn by hand today, but we still harvest lettuces and nuts and apples by hand,” Boyer says.

      The Titan was built to complement field workers’ efforts to grow and maintain crops. An operator directs it using an iPad, walking alongside the machine and inspecting progress. Both the Titan and Vulcan are powered by an AI that directs hundreds of tiny blades to snip out weeds around each crop. The Vulcan is controlled directly from the tractor cab, where the operator has a touchscreen interface Boyer compares to those found in a Tesla.

      With more than 15,000 commercial hours under its belt, FarmWise hopes the data it collects can be used for more than just weeding in the near future.

      “It’s all about precision,” Boyer says. “We’re going to better understand what the plant needs and make smarter decisions for each one. That will bring us to a point where we can use the same amount of land, much less water, almost no chemicals, much less fertilizer, and still produce more food than we’re producing today. That’s the mission. That’s what excites me.”

      Weeding out farming challenges

      A customer recently told Boyer that without the Titan, he would have to switch all of his organic crops back to conventional because he couldn’t find enough workers.

      “That’s happening with a lot of customers,” Boyer says. “They have no choice but to rely on herbicides. Acres are staying organic because of our product, and conventional farms are reducing their use of herbicides.”

      Now FarmWise is expanding its database to support weeding for six to 12 new crops each year, and Boyer says adding new crops is getting easier and easier for its system.

      As early partners have sought to expand their deployments, Boyer says the only thing limiting the company’s growth is how fast it can build new robots. FarmWise’s new machines will begin being deployed later this year.

      Although the hulking Titan robots are the face of the company today, the founders hope to leverage the data they’ve collected to further improve farming operations.

      “The mission of the company is to turn AI into a tool that is as reliable and dependable as GPS is now in the farming industry,” Boyer says. “Twenty-five years ago, GPS was a very complicated technology. You had to connect to satellites and do some crazy computation to define your position. But a few companies brought GPS to a new level of reliability and simplicity. Today, every farmer in the world uses GPS. We think AI can have an even deeper impact than GPS has had on the farming industry, and we want to be the company that makes it available and easy to use for every farmer in the world.” More

    • 150 Shares169 Views

      in Security

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

      by

      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

    • 75 Shares149 Views

      in Security

      Food for thought, thought for food

      by

      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