Tools for Mars are being developed in preparation for colonization
Turns out chitin is quite useful when you need a wrench.
18 September, 2020
Credit: Dotted Yeti / Shutterstock
- Researchers at the Singapore University of Technology and Design constructed Mars-ready tools in preparation for colonization.
- The team chose chitin as a cheap and abundant material to fashion a wrench and habitat.
- Chitin occurs naturally in arthropod exoskeletons, fungus, and fish scales.
<p>In 1963, a spaceship crash-landed on Earth. The vehicle was carrying one Martian, a very man-like creature who would be called Uncle Martin. He was so named by Tim O'Hara, a local newspaper reporter that discovered him. Incredibly, the martian spoke English.</p><p>Before becoming the Incredible Hulk, actor Bill Bixby played the role of Tim, whose "uncle" (Ray Waltson) arrived intact from the Red Planet, in "My Favorite Martian." Both "martian" and "Martin" derive from the word <em>Mars</em>, the Roman god of war and, before that, the fourth planet from the sun. </p><p>We've long been fascinated with Mars and the idea of getting there. There's more talk about colonizing that planet than terraforming our moon. Current plans have humans using the Moon as a weigh station to leap from. NASA is <a href="https://www.cnet.com/news/nasa-mars-rover-runs-first-of-its-kind-experiment-seeking-clues-to-ancient-life/" target="_blank">currently investigating</a> the possibility of ancient life on Mars, though more forward-thinking researchers are now building tools for our arrival. </p><p>A team led by Javier Fernandez of Singapore University of Technology and Design has found a candidate for construction: chitin. In a <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0238606" target="_blank" rel="noopener noreferrer">new research article</a>, published in PLOS One, the researchers suggested using this organic polymer to fashion tools and build shelter. </p><p>Chitin is a derivative of glucose and is comparable in function to keratin. Its structure was discovered by Albert Hofmann in 1929, nearly a decade before the Swiss chemist stumbled into LSD and went on his famous <a href="https://www.inverse.com/article/14503-bicycle-day-albert-hofmann-lsd-acid-trip" target="_blank">bicycle trip</a>. Agriculturists have since explored its function as a soil fertilizer, while chitin has long been used to thicken and stabilize foods. The polymer occurs naturally in arthropod exoskeletons, fungus, and fish scales. </p><p>As Silicon Valley's elite set and government agencies dream of crewing a mission to Mars by the late 2030s, Fernandez and crew want to offer practical advice for manufacturing technologies needed when colonizing a planet. As they write, "a sustainable extraterrestrial settlement must be a resource-efficient, closed ecological system."</p>
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQyMjAyMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0Njc4NzM2N30.WXUPthSGHHLthuMpfEcyKpDxNV8M4d1l4DsV002w--o/img.jpg?width=980" id="76825" class="rm-shortcode" data-rm-shortcode-id="0b3ef19917ebce5ed7d371a990adbb4f" data-rm-shortcode-name="rebelmouse-image" alt="Mars landscape" />
<p class=""><br></p>In this handout released by NASA, a Mars landscape is seen in a picture taken by the panoramic camera on the Mars Exploration Rover Spirit January 8, 2003.
Credit:NASA/Jet Propulsion Laboratory/Cornell University via Getty Images
<p>Then there's the matter of cost. You can't simply take Earth's wares and think they'll work on Mars. If you're looking for the most bang for your buck, they believe they've identified a winner.</p><p style="margin-left: 20px;">"Chitin is a paradigmatic example of an organic matrix of mineralized composites; it is the second most abundant organic polymer on Earth (after cellulose) and biology's recurrent solution to forming structural components."</p><p>Even better, no specialized equipment will need to be spun up. Chitin's ubiquity makes it easy to source. The team combined chitosan with minerals akin to Martian soil, designing a wrench as well as a full-scale habitat. </p><p>The team recognizes the challenges of building materials designed for an alien civilization, but feel it's better to start now than for those brave explorers to arrive with shoddy tents. They were able to rapidly and inexpensively produce these products, which they believe could aid in "our transformation into an interplanetary species." Fernandez <a href="https://phys.org/news/2020-09-chitin-bioinspired-material-tools-mars.html" target="_blank">continues</a>:</p><p style="margin-left: 20px;">"The technology was originally developed to create circular ecosystems in urban environments, but due to its efficiency, it is also the most efficient and scalable method to produce materials in a closed artificial ecosystem in the extremely scarce environment of a lifeless planet or satellite."</p><p>The emphasis on sustainability and expense is important as we prepare to leave this planet. Hopefully, the martians will appreciate the effort. </p><p>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank" rel="noopener noreferrer">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
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Is it possible to build a mile-high skyscraper?
A mile-high tower would not just be a new structure, but a new technology.
14 September, 2020
Courtesy of Neomam Studio
- Frank Lloyd Wright originally proposed The Mile-High Illinois in the 1950s.
- Innovations in construction materials and elevators are necessary to reach the one mile height and beyond.
- We may see the first mile-high skyscraper by the middle of the 21st century.
<p>Humanity has been on a quest for millenia to build bigger and taller structures. In our reach skyward we've built ziggurats, pyramids, and coliseums. Our mythologies placed the seat of the gods in lofty towers high on mountaintops. We've had moralizing religious parables like the Tower of Babel, warning those who'd place themselves above a god. And some of the self-proclaimed greatest among us have always sought to immortalize themselves through massive works.</p><p>It's safe to say our world civilization is one fixed on achieving ever higher <em>milestones.</em></p><p>Yet, the dreams and wonders of yesterday's buildings look like children's toys compared to our structures now. In the past century and a half skyscrapers have come to dominate the city's form and they haven't stopped growing taller. </p><p>Now we have to ask ourselves, is it possible to build a skyscraper one mile high? </p><p>Perhaps. Let's find out. </p>
Frank Lloyd Wright’s The Mile-High Illinois
<p>One of the first legitimate plans to build a mile-high tower that wasn't some megalomaniac's fever dream (maybe his was too), was famed architect Frank Lloyd Wright's The Illinois. </p><p>On October 16th, 1956 at the Sherman House Hotel in Chicago, Wright at 89 years old presented his design for what he conceived to be the tallest skyscraper in the world, an incredible spire shooting one mile high. The structure proposed to stand 528 floors and 5,280 feet (1,609 meters) tall. Behind him stood an illustration that measured 25 feet (7.6 meters) tall with the skyscraper's dimensions drawn at a scale of 1/16 inch to the foot. The Illinois' dimensions would have been astronomical at the time, with: </p><ul><li>528 floors </li><li>76 elevators </li><li>Gross floor area (GFA): 18,460,106 ft² (1,715,000 m²)</li><li>100,000 occupants </li><li>15,000 parking spaces </li><li>100 helicopter landing pads </li><li>Architectural height of 5,280 ft (1,609.4 m)</li><li>Tip antenna height of 5,706 ft (1739.2 m)</li></ul><p>"This is The Illinois, gentlemen… In it, will be consolidated all government offices now scattered around Chicago," Wright proclaimed.</p><img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDMxODc3NC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MjAwNDU2NH0.eJMPnaR6TpYJGS2J08lHCQDRUQtdzVVCJOI8jmcjPK8/img.jpg?width=980" id="61570" class="rm-shortcode" data-rm-shortcode-id="34c0f1f6be1aa9541ef9818dc89910f5" data-rm-shortcode-name="rebelmouse-image" />
Frank Lloyd Wright presents The Mile High Illinois at the Sherman House Hotel in Chicago
Credit: Alamy Photos
<p>Wright in an exemplary display of showmanship unveiled the first proposal for the mile-high tower. He believed that he'd found a method to construct the tower out of two principles he coined "tenuity" and "continuity." With these methods he'd believed he would be able to construct the tower out of reinforced concrete and steel.</p> <p>The general principles between these two ideas is characterized by Wright's designs in which he used a "taproot" foundation to support the central load of the structure. </p> <p><a href="https://www.chicagotribune.com/columns/ct-frank-lloyd-wright-mile-high-met-0528-20170528-column.html" target="_blank" rel="noopener noreferrer">Chicago Tribune's Blaire Kamin</a> described it as follows: </p> <p> "The Mile-High didn't simply aim to be tall. It was the ultimate expression of Wright's "taproot" structural system, which sank a central concrete mast deep into the ground and cantilevered floors from the mast. In contrast to a typical skyscraper, in which same-size floors are piled atop one another like so many pancakes, the taproot system lets floors vary in size, opening a high-rise's interior and letting space flow between floors."</p><p><br></p><p>In Wright's own words he saw his method as a break from conventional form, which instead he'd mimic the appearance of a tree with its deep roots and branches spreading deep into the foundation. </p><p>"I detest seeing the boys fooling around and making their buildings look like boxes," Wright said. "Why not design a building that really is tall? ... Long ago I observed trees after the passing of a cyclone. Those with deep taproots were the ones that survived."</p><p>As evident by our lack of sky cracking buildings, Wright's vision never came to pass. His taproot idea, which had only been put into practice in a single building of his, never became part of the future structural engineer's toolkit. While Wright did put an extraordinary amount of effort working out the details of this vision, there were far too many what-ifs that still hadn't been figured out. Many of which we're still working on today.</p><p>But there has been progress. </p>
Building technology for a 1-mile skyscraper
<p>The undefeated champion of the skies right now is the Burj Khalifa in Dubai, which stands at 2,717 feet (roughly half a mile) and is the tallest building in the world.</p><p>Although take that with a grain of dusty salt—only 1,916 feet of the Burj Dubai is occupiable space, the rest is vanity height, meaning nearly 800 feet is non-occupiable space. That represents 29 percent of the building's height. </p><p>So let's get back to real contenders for a mile high.</p><a href="https://www.technologyreview.com/2018/08/20/2343/get-ready-for-more-and-taller-skyscrapers/" target="_blank" rel="noopener noreferrer">Researchers at MIT Technology Review</a> used data from the experts at the Council on Tall Buildings and Urban Habitat and predicted that there is a 9 percent chance that a building exceeding a mile will be built by 2050. They've also predicted that by 2050, nearly 6 billion people will live in cities. Already we're seeing that urban areas in China and the Middle East are continually building up, not out.<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDEwMDM3NC9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY0OTU5NzI4N30.C_l0mR6PFVdr0ZQQiRXBuonLrJoUXgcgfKaqKhWspSw/img.png?width=980" id="44cfe" class="rm-shortcode" data-rm-shortcode-id="238570ff6e5ed8c7afb2c6ec42cf7818" data-rm-shortcode-name="rebelmouse-image" />
Credit: Jonathan Auerbach and Phyllis Wan, International Journal of Forecasting Vol. 36, Issue 3
<p>There are three major construction and stability aspects that must be dealt with if we're to reach a vertical mile. Those are:</p><ul><li>Dampening wind sway </li><li>Elevator speed and length </li><li>Construction materials </li></ul><p>The tallest skyscrapers all employ a tapered top design. This serves both a utilitarian and structural purpose. It's simply not possible to take pre-existing buildings and just double their height. </p><p>A mile-high tower would not just be a new structure, but a new technology. </p><p>Putting aside Burj Khalifa's vanity height for a moment, we have to admire its structural ingenuity. Designed by architect Adrian Smith and structural engineer William Baker at Skidmore, Owings and Merrill, the structure's foundational approach is a buttressed core – which is a hexagonal concrete core that frays out into three triangle buttresses. This was one inventive solution they made to support such a great height. </p><p>But that only solves one issue. </p><p><strong>Diverting winds at high elevations</strong> </p><p>What might be a slight breeze on the ground floor can turn into a windstorm in greater heights. Aside from the fundamentals of stability, occupants also need comfortability. Most building sway is harmless to the structural integrity of the building. But the last thing anyone wants is to feel like they're in the midst of a tornado 500 floors above ground level. </p><p>Architecture, engineering, and construction (AEC) professionals calculate estimated wind sway from a building's height and incorporate that into the design. Buildings are often made to withstand cataclysmic 500 to 1000 year inclement weather disasters. </p><p>To deal with wind, you either confuse it by spinning it around the building in creative structural ways or you use a mass dampener.</p><p>A mass dampener is a counterweight suspended somewhere in the building to counteract and balance the movement from the outside. For example, the Taipei 101 Tower employs a <a href="https://gizmodo.com/how-a-730-ton-ball-kept-the-second-tallest-building-fro-5019046" target="_blank">730 ton orb </a>pendulum that sways back and forth to balance wind from storms and typhoons. </p><p>Aerodynamic vortexes of wind can exert dangerous amounts of pressure and vibrations on a building. Air currents can be unpredictable, so rather than guess what could happen to the building, AEC professionals need to calculate it directly into the design. If it's not a mass dampener, it'll be a mix of structural fins, curves, and asymmetrical floors. </p><p><strong>Elevator speed and stability</strong> </p><p>The logistical obstacles of moving thousands of people in a mile-high skyscraper is one of the biggest challenges. To reach the floor at the top of a mile-high building with current technology would require people to change elevators multiple times. </p><p>The current figure for elevators runs at 1,600 feet as wire suspension ropes cannot support their own weight and any additional weight after that point. Aside from the technical limitations, needing multiple elevator lobbies would take up too much valuable space. </p><p>A few years ago, Finnish elevator company Kone developed a carbon fiber cable, UltraRope that they believe could double the distance of an elevator rope. This would be enough to get those would-be mile-high penthouse residents to their sky digs. </p><p>Beyond the old school cable elevator, others have floated ideas about a looped system that could pull elevators up, down and sideways. This could increase the building's usable area by 25 percent. </p><p><strong>New structural materials</strong> </p><p>Concrete has served us well for thousands of years. It's time to rethink what materials we can use. Engineers are looking at materials like carbon fiber, an extremely lightweight and strong material. </p><p>Carbon fiber is a polymer composed of thin strands of carbon atoms bound together in a unique crystalline formation. It is far lighter than steel, five times stronger and has double the stiffness. Currently carbon fiber is used in a number of manufacturing processes ranging from aircraft wings to bike frames. Carbon fiber and other related composite materials weigh very little but can take on heavy bearing loads.</p>The future of the mile-high skyscraper
<p>With billions of residents in our cities, it's an inevitability that we'll one day reach the one-mile-high mark, if not beyond that as well. But we need to think about what these skyscrapers will be used for and how they'll interact with and reshape the built environment. </p><p>At the turn of the 20th century, the 1916 Zoning Resolution in New York City was a measure adopted to stop massive skyscrapers from blocking light and air from reaching the streets below. It established limits to what could be built and created a series of setbacks to building lots. </p><p>New measures would need to be created as a building of this magnitude entered into the public domain. New building uses also need to be considered. How many more luxury condos and office space do we really need? </p><p>The advent of a mile-high tower could bring about a new age of the homestead and of our created environment. We have the opportunity to build something that could be a fully functioning self-contained ecosystem, more than just a building, but a city within a city. </p><p>A mixed use building like this could shelter thousands and give them a place where they could work, play, live, and exist on the peripheries of humankind's greatest ingenuity. A place like this could also serve as a consolidated seat for governments and working space for companies of the future. Why not continue to build vertically with farms, factories, and more?<br></p><p>When we one day build to a mile and beyond, the sky will no longer be the limit, it will be our domain.</p><p><em></em><em>Mike Colagrossi is the founder of </em><em><a target="_blank" href="https://alchemistcity.com/?utm_source=bigthink&utm_medium=editorial&utm_campaign=mile-high-skyscraper">Alchemist City,</a></em><em> the most thought-provoking urban development and technology email newsletter. </em><em><a target="_blank" href="https://alchemistcity.com/?utm_source=bigthink&utm_medium=editorial&utm_campaign=mile-high-skyscraper" rel="noopener noreferrer">Sign up</a></em><em> to stay up to date.</em> <em></em></p>
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NASA-funded scientist says 'MEGA drive' could enable interstellar travel
The drive would provide enough thrust for a spacecraft to travel near the speed of light using only electricity, says physicist Jim Woodward.
07 September, 2020
- The thrust system utilizes piezoelectric crystals, which vibrate extremely rapidly when exposed to electric current.
- Early tests have yielded mixed results, but Woodward and his colleagues say a recent breakthrough related to the design of the thruster mount greatly increased thrust.
- Independent teams of scientists will likely test Woodward's design after the pandemic.
<p>From health concerns to funding, there's no shortage of obstacles preventing humans from traveling beyond our solar system. But the main obstacle is propulsion: Our spacecraft are simply too slow and too reliant on fuel to realistically make a voyage to Alpha Centauri, the closest star to our Sun.</p><p>So, what do we need? Something like a reactionless drive — an engine that moves a spacecraft without exhausting a finite stock of propellant. So far, such a device only exists in science fiction. But for the past few decades, physicist Jim Woodward has been trying to change that.</p><p>The 79-year-old physics professor has developed what a thruster design that he hopes will serve as a proof of concept for how humans can someday achieve interstellar travel. Called the Mach-effect gravitational assist (MEGA) drive, the device only requires a source of electricity to achieve thrust. </p><p>Early tests have shown mixed results. Woodward himself was only able to demonstrate miniscule amounts of thrust, while other teams reported little to no thrust when trying to replicate his experiments. Still, the design intrigued NASA enough to award Woodward $625,000 in funding between 2017 and 2018. </p><p>What's more, in 2019 Woodward and his collaborator and fellow physicist Hal Fearn reported a major breakthrough after redesigning the thruster's mount — a tweak that produced "more than 100 micronewtons, orders of magnitude larger than anything Woodward had ever built before," as a recent feature in <a href="https://www.wired.com/story/mach-effect-thrusters-interstellar-travel/" target="_blank" style="">Wired</a> notes. </p><p>(To be sure, the level of thrust we're talking about is barely enough to visibly move an object across a table. But if the results are confirmed, it would suggest the technology could be scaled up.)</p>
A heterodox view of inertia
<p>Woodward's system is based on ideas that 19th-century physicist Ernst Mach proposed about inertia, which is an object's tendency to stay at rest unless acted upon.</p><p>In simple terms, Mach's principle argues that distant matter causes local inertial effects. So, a star in a far away galaxy has some effect on the inertia you encounter when you push a shopping cart. That's the idea, anyway. (Woodward gives a comprehensive breakdown of his views on Mach's principle in this <a href="https://medium.com/predict/james-woodward-on-machs-principle-for-reactionless-inertial-propulsion-34384863ad50" target="_blank">blog post</a>.)</p><p><span></span>In the 20th century, Albert Einstein incorporated Mach's ideas into his theory of general relativity, essentially arguing that gravity and inertia are fundamentally linked. But the broader physics community later rejected this view of inertia, largely because of a <a href="http://people.loyno.edu/~brans/ST-history/phd-thesis-Brans.pdf" target="_blank">1961 paper</a> that showed inertia to be unrelated to the gravitational influence of distant matter.</p><p>Still, Woodward believes Einstein had it right all along, and that, under this framework of inertia, it's possible to develop propulsion systems that require only an electrical charge, not fuel. The key element of his thruster is a stack of piezoelectric crystals, which produces an alternating electric field when voltage is applied to it, as Woodward explained:</p><p style="margin-left: 20px;">"Piezoelectric crystals are <a href="https://en.wikipedia.org/wiki/Electromechanics" target="_blank">electromechanical</a> devices, which means that when you apply the voltage, they mechanically expand & contract depending upon the sign of the voltage. So by applying a voltage, you're causing an E/c² energy fluctuation in the stack no matter what they do mechanically, and you're also producing an acceleration because of the changing dimensions of the stack due due to electromechanical effects, which also causes the acceleration required couple the device to the large gravitational field."</p><p style="margin-left: 20px;">"The trick is timing the energy fluctuations and mechanical oscillations correctly, which requires using two frequencies — at the first and second harmonics, and it's the second harmonic that actually produces thrust."</p><span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="ad94a778bf9379d610884cc629149e99"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/OLs9NEt9LRQ?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>Woodward and his colleagues have even drawn up plans for a spacecraft that would utilize the MEGA drive. Called the SSI Lambda, the craft would feature piezoelectric crystals and a small nuclear reactor to produce electricity.</p><p style="margin-left: 20px;">"The SSI Lambda probe using MEGA drive thrusters is a truly propellantless-propulsion spacecraft," the team wrote of the design in its report to NASA. "It can travel at speeds up to the speed of light in a vacuum with only consumption of electric power. No other method for travelling to the stars and braking into the target system has been put forward to date, which also has credible physics to back it up."</p>
High-reward work
<p>After the COVID-19 pandemic settles down, other scientists and engineers hope to put Woodward's designs to the test. The results of those experiments should reveal whether he's onto something. To some experts in the field, the odds are slim. But that doesn't mean it's not worth investigating.</p><p style="margin-left: 20px;">"I'd say there's between a 1-in-10 and 1-in-10,000,000 chance that it's real, and probably toward the higher end of that spectrum," Mike McDonald, an aerospace engineer at the Naval Research Laboratory in Maryland, told Wired. "But imagine that one chance; that would be amazing. That's why we do high-risk, high-reward work. That's why we do science."</p>
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Engineers use “DNA origami” to identify vaccine design rules
DNA molecules are highly programmable.
23 August, 2020
Matt Cardy/Getty Images
By folding DNA into a virus-like structure, MIT researchers have designed HIV-like particles that provoke a strong immune response from human immune cells grown in a lab dish. Such particles might eventually be used as an HIV vaccine.
<p>The DNA particles, which closely mimic the size and shape of viruses, are coated with HIV proteins, or antigens, arranged in precise patterns designed to provoke a strong immune response. The researchers are now working on adapting this approach to develop a potential vaccine for SARS-CoV-2, and they anticipate it could work for a wide variety of viral diseases.</p><p>"The rough design rules that are starting to come out of this work should be generically applicable across disease antigens and diseases," says Darrell Irvine, who is the Underwood-Prescott Professor with appointments in the departments of Biological Engineering and Materials Science and Engineering; an associate director of MIT's Koch Institute for Integrative Cancer Research; and a member of the Ragon Institute of MGH, MIT, and Harvard.</p><p>Irvine and Mark Bathe, an MIT professor of biological engineering and an associate member of the Broad Institute of MIT and Harvard, are the senior authors of the study, which appears today in <em>Nature Nanotechnology</em>. The paper's lead authors are former MIT postdocs Rémi Veneziano and Tyson Moyer.</p>
<h3>DNA design</h3><p>Because DNA molecules are highly programmable, scientists have been working since the 1980s on methods to design DNA molecules that could be used for drug delivery and many other applications, most recently using a technique called DNA origami that was invented in 2006 by Paul Rothemund of Caltech.</p><p>In 2016, Bathe's lab developed an algorithm that can automatically design and build arbitrary three-dimensional <a href="http://news.mit.edu/2016/automating-dna-origami-opens-door-many-new-uses-0526" target="_blank" rel="noopener noreferrer dofollow">virus-like shapes</a> using DNA origami. This method offers precise control over the structure of synthetic DNA, allowing researchers to attach a variety of molecules, such as viral antigens, at specific locations.</p><p>"The DNA structure is like a pegboard where the antigens can be attached at any position," Bathe says. "These virus-like particles have now enabled us to reveal fundamental molecular principles of immune cell recognition for the first time."</p><p>Natural viruses are nanoparticles with antigens arrayed on the particle surface, and it is thought that the immune system (especially B cells) has evolved to efficiently recognize such particulate antigens. Vaccines are now being developed to mimic natural viral structures, and such nanoparticle vaccines are believed to be very effective at producing a B cell immune response because they are the right size to be carried to the lymphatic vessels, which send them directly to B cells waiting in the lymph nodes. The particles are also the right size to interact with B cells and can present a dense array of viral particles.</p>
<p>However, determining the right particle size, spacing between antigens, and number of antigens per particle to optimally stimulate B cells (which bind to target antigens through their B cell receptors) has been a challenge. Bathe and Irvine set out to use these DNA scaffolds to mimic such viral and vaccine particle structures, in hopes of discovering the best particle designs for B cell activation.</p><p>"There is a lot of interest in the use of virus-like particle structures, where you take a vaccine antigen and array it on the surface of a particle, to drive optimal B-cell responses," Irvine says. "However, the rules for how to design that display are really not well-understood."</p><p>Other researchers have tried to create subunit vaccines using other kinds of synthetic particles, such as polymers, liposomes, or self-assembling proteins, but with those materials, it is not possible to control the placement of viral proteins as precisely as with DNA origami.</p>
<p>For this study, the researchers designed icosahedral particles with a similar size and shape as a typical virus. They attached an engineered HIV antigen related to the gp120 protein to the scaffold at a variety of distances and densities. To their surprise, they found that the vaccines that produced the strongest response B cell responses were not necessarily those that packed the antigens as closely as possible on the scaffold surface.</p><p>"It is often assumed that the higher the antigen density, the better, with the idea that bringing B cell receptors as close together as possible is what drives signaling. However, the experimental result, which was very clear, was that actually the closest possible spacing we could make was not the best. And, and as you widen the distance between two antigens, signaling increased," Irvine says.</p><p>The findings from this study have the potential to guide HIV vaccine development, as the HIV antigen used in these studies is currently being tested in a clinical trial in humans, using a protein nanoparticle scaffold.</p><p>Based on their data, the MIT researchers worked with Jayajit Das, a professor of immunology and microbiology at Ohio State University, to develop a model to explain why greater distances between antigens produce better results. When antigens bind to receptors on the surface of B cells, the activated receptors crosslink with each other inside the cell, enhancing their response. However, the model suggests that if the antigens are too close together, this response is diminished.</p>
<h3>Beyond HIV</h3><p>In recent months, Bathe's lab has created a variant of this vaccine with the Aaron Schmidt and Daniel Lingwood labs at the Ragon Institute, in which they swapped out the HIV antigens for a protein found on the surface of the SARS-CoV-2 virus. They are now testing whether this vaccine will produce an effective response against the coronavirus SARS-CoV-2 in isolated B cells, and in mice.</p><p>"Our platform technology allows you to easily swap out different subunit antigens and peptides from different types of viruses to test whether they may potentially be functional as vaccines," Bathe says.</p><p>Because this approach allows for antigens from different viruses to be carried on the same DNA scaffold, it could be possible to design variants that target multiple types of coronaviruses, including past and potentially future variants that may emerge, the researchers say.</p><p>Bathe was recently awarded a grant from the Fast Grants Covid-19 fund to develop their SARS-CoV-2 vaccine. The HIV research presented in the <em>Nature Nanotechnology</em> paper was funded by the Human Frontier Science Program, the U.S. Office of Naval Research, the U.S. Army Research Office through MIT's Institute for Soldier Nanotechnologies, the Ragon Institute, and the U.S. National Institutes of Health.</p><p>Reprinted with permission of <a href="http://news.mit.edu/" target="_blank" rel="noopener noreferrer dofollow">MIT News</a>. Read the <a href="https://news.mit.edu/2020/dna-origami-vaccine-design-rules-0629" target="_blank">original article</a>.</p>
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Coding is not ‘fun’, it’s technically and ethically complex
It doesn't help that Hollywood has cast the 'coder' as a socially challenged, type-first-think-later hacker, inevitably white and male.
16 August, 2020
Photo by ThisisEngineering RAEng on Unsplash
Programming computers is a piece of cake. Or so the world's digital-skills gurus would have us believe.
<p> From the non-profit Code.org's promise that 'Anybody can learn!' to Apple chief executive Tim Cook's comment that writing code is 'fun and interactive', the art and science of making software is now as accessible as the alphabet. </p><p>Unfortunately, this rosy portrait bears no relation to reality. For starters, the profile of a programmer's mind is pretty uncommon. As well as being highly analytical and creative, software developers need almost superhuman focus to manage the complexity of their tasks. Manic attention to detail is a must; slovenliness is <em>verboten</em>. Attaining this level of concentration requires a state of mind called being 'in the flow', a quasi-symbiotic relationship between human and machine that improves performance and motivation.</p><p>Coding isn't the only job that demands intense focus. But you'd never hear someone say that brain surgery is 'fun', or that structural engineering is 'easy'. When it comes to programming, why do policymakers and technologists pretend otherwise? For one, it helps lure people to the field at a time when software (in the words of the venture capitalist Marc Andreessen) is 'eating the world' – and so, by expanding the labour pool, keeps industry ticking over and wages under control. Another reason is that the very word 'coding' sounds routine and repetitive, as though there's some sort of key that developers apply by rote to crack any given problem. It doesn't help that Hollywood has cast the 'coder' as a socially challenged, type-first-think-later hacker, inevitably white and male, with the power to thwart the Nazis or penetrate the CIA.</p>
<p>Insisting on the glamour and fun of coding is the wrong way to acquaint kids with computer science. It insults their intelligence and plants the pernicious notion in their heads that you don't need discipline in order to progress. As anyone with even minimal exposure to making software knows, behind a minute of typing lies an hour of study.</p><p>It's better to admit that coding is complicated, technically and ethically. Computers, at the moment, can only execute orders, to varying degrees of sophistication. So it's up to the developer to be clear: the machine does what you say, not what you mean. More and more 'decisions' are being entrusted to software, including life-or-death ones: think self-driving cars; think semi-autonomous weapons; think Facebook and Google making inferences about your marital, psychological or physical status, before selling it to the highest bidder. Yet it's rarely in the interests of companies and governments to encourage us to probe what's going on beneath these processes.</p>
<p>All of these scenarios are built on exquisitely technical foundations. But we can't respond to them by answering exclusively technical questions. Programming is not a detail that can be left to 'technicians' under the false pretence that their choices will be 'scientifically neutral'. Societies are too complex: the algorithmic is political. Automation has already dealt a blow to the job security of low-skilled workers in factories and warehouses around the world. White-collar workers are next in line. The digital giants of today run on a fraction of the employees of the industrial giants of yesterday, so the irony of encouraging more people to work as programmers is that they are slowly mobilising themselves out of jobs.</p><p>In an ever-more intricate and connected world, where software plays a larger and larger role in everyday life, it's irresponsible to speak of coding as a lightweight activity. Software is not simply lines of code, nor is it blandly technical. In just a few years, understanding programming will be an indispensable part of active citizenship. The idea that coding offers an unproblematic path to social progress and personal enhancement works to the advantage of the growing techno-plutocracy that's insulating itself behind its own technology.<img src="https://metrics.aeon.co/count/ead5db81-b8d1-4e6a-9683-532622b4ab3e.gif" alt="Aeon counter – do not remove"></p><p>This article was originally published at <a href="https://aeon.co/?utm_campaign=republished-article" target="_blank">Aeon</a> and has been republished under Creative Commons. Read the <a href="https://aeon.co/ideas/coding-is-not-fun-it-s-technically-and-ethically-complex" target="_blank">original article</a>.</p>
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