Complex interlocking components mean no tools are needed. Credit: © Larsson et al.

An interactive system to design and fabricate structurally sound wood joints.

Wood is considered an attractive construction material for both aesthetic and environmental purposes. Construction of useful wood objects requires complicated structures and ways to connect components together. Researchers created a novel 3D design application to hugely simplify the design process and also provide milling machine instructions to efficiently produce the designed components. The designs do not require nails or glue, meaning items made with this system can be easily assembled, disassembled, reused, repaired, or recycled.

Carpentry is a practice as ancient as humanity itself. Equal parts art and engineering, it has figuratively and literally shaped the world around us. Yet despite its ubiquity, carpentry is a difficult and time-consuming skill, leading to relatively high prices for hand-crafted wooden items like furniture. For this reason, much wooden furniture around us is often, at least to some degree, made by machines. Some machines can be highly automated and programmed with designs created on computers by human designers. This in itself can be a very technical and creative challenge, out of reach to many, until now.

Tsugite has an intuitive interface to present users with design options. Credit: © Larsson et al.

Researchers from the Department of Creative Informatics at the University of Tokyo have created a 3D design application to create structural wooden components quickly, easily, and efficiently. They call it Tsugite, the Japanese word for joinery, and through a simple 3D interface, users with little or no prior experience in either woodworking or 3D design can create designs for functional wooden structures in minutes. These designs can then instruct milling machines to carve the structural components, which users can then piece together without the need for additional tools or adhesives, following on-screen instructions.

“Our intention was to make the art of joinery available to people without specific experience. When we tested the interface in a user study, people new to 3D modeling not only designed some complex structures, but also enjoyed doing so,” said researcher Maria Larsson. “Tsugite is simple to use as it guides users through the process one step at a time, starting with a gallery of existing designs that can then be modified for different purposes. But more advanced users can jump straight to a manual editing mode for more freeform creativity.”

All seven unique ways that two pieces can be joined in Tsugite. Credit: © Larsson et al.

Tsugite gives users a detailed view of wooden joints represented by what are known as voxels, essentially 3D pixels, in this case small cubes. These voxels can be moved around at one end of a component to be joined; this automatically adjusts the voxels at the end of the corresponding component such that they are guaranteed to fit together tightly without the need for nails or even glue. Two or more components can be joined and the software algorithm will adjust all accordingly. Different colors inform the user about properties of the joints such as how easily they will slide together, or problems such as potential weaknesses.

Something that makes Tsugite unique is that it will factor the fabrication process directly into the designs. This means that milling machines, which have physical limitations such as their degrees of freedom, tool size and so on, are only given designs they are able to create. Something that has plagued users of 3D printers, which share a common ancestry with milling machines, is that software for 3D printers cannot always be sure how the machine itself will behave which can lead to failed prints.

“There is some great research in the field of computer graphics on how to model a wide variety of joint geometries. But that approach often lacks the practical considerations of manufacturing and material properties,” said Larsson. “Conversely, research in the fields of structural engineering and architecture may be very thorough in this regard, but they might only be concerned with a few kinds of joints. We saw the potential to combine the strengths of these approaches to create Tsugite. It can explore a large variety of joints and yet keeps them within realistic physical limits.”

Another advantage of incorporating fabrication limitations into the design process is that Tsugite’s underlying algorithms have an easier time navigating all the different possibilities they could present to users, as those that are physically impossible are simply not given as options. The researchers hope through further refinements and advancements that Tsugite can be scaled up to design not just furniture and small structures, but also entire buildings.

“According to the U.N., the building and construction industry is responsible for almost 40% of worldwide carbon dioxide emissions. Wood is perhaps the only natural and renewable building material that we have, and efficient joinery can add further sustainability benefits,” said Larsson. “When connecting timbers with joinery, as opposed to metal fixings, for example, it reduces mixing materials. This is good for sorting and recycling. Also, unglued joints can be taken apart without destroying building components. This opens up the possibility for buildings to be disassembled and reassembled elsewhere. Or for defective parts to be replaced. This flexibility of reuse and repair adds sustainability benefits to wood.”

Reference: “Tsugite: Interactive Design and Fabrication of Wood Joints” by Maria Larsson, Hironori Yoshida, Nobuyuki Umetani and Takeo Igarashi, October 2020, Proceedings of the 32nd Annual ACM Symposium on User Interface Software and Technology (UIST ’20).
DOI: 10.1145/3379337.3415899

This research is supported by JST ACT-I grant number JPMJPR17UT, JSPS KAKENHI grant number 17H00752, and JST CREST grant number JPMJCR17A1, Japan.

Native to desert habitats in Southern California, the diabolical ironclad beetle has an exoskeleton that’s one of the toughest, most crush-resistant structures known to exist in the animal kingdom. UCI researchers led a project to study the components and architectures responsible for making the creature so indestructible. Credit: David Kisailus / UCI

Getting run over by a car is not a near-death experience for the diabolical ironclad beetle.

How the beetle survives could inspire the development of new materials with the same herculean toughness, engineers show in a paper published today (Wednesday, October 21, 2020) in Nature.

These materials would be stiff but ductile like a paper clip, making machinery such as aircraft gas turbines safer and longer-lasting, the researchers said.

The study, led by engineers at the University of California, Irvine (UCI) and Purdue University, found that the diabolical ironclad beetle’s super-toughness lies in its two armorlike “elytron” that meet at a line, called a suture, running the length of the abdomen.

In flying beetles, the elytra protect wings and facilitate flight. But the diabolical ironclad beetle doesn’t have wings. Instead, the elytra and connective suture help to distribute an applied force more evenly throughout its body.

“The suture kind of acts like a jigsaw puzzle. It connects various exoskeletal blades — puzzle pieces — in the abdomen under the elytra,” said Pablo Zavattieri, Purdue’s Jerry M. and Lynda T. Engelhardt Professor of Civil Engineering.

This jigsaw puzzle comes to the rescue in several different ways depending on the amount of force applied, Zavattieri said. This video explains these findings:

The diabolical ironclad beetle is so tough, it can survive getting run over by a car applying ~100 newtons of force. Engineers from Purdue University and UC-Irvine teamed up to unlock the beetle’s secrets. Credit: Purdue University/Erin Easterling

To uncover these strategies, a team led by UCI professor David Kisailus first tested the limits of the beetle’s exoskeleton and characterized the various structural components involved by looking at CT scans.

Using compressive steel plates, UCI researchers found that the diabolical ironclad beetle can take on an applied force of about 150 newtons — a load of at least 39,000 times its body weight — before the exoskeleton begins to fracture.

That’s more impressive than sounds: A car tire would apply a force of about 100 newtons if running over the beetle on a dirt surface, the researchers estimate. Other terrestrial beetles the team tested couldn’t handle even half the force that a diabolical ironclad can withstand.

Zavattieri’s lab followed up these experiments with extensive computer simulations and 3D-printed models that isolated certain structures to better understand their role in saving the beetle’s life.

All of these studies combined revealed that when under a compressive load such as a car tire, the diabolical ironclad beetle’s jigsaw-like suture offers two lines of defense.

The diabolical ironclad beetle has puzzle piece-like blades in its abdomen that “delaminate” to prevent the beetle’s exoskeleton from suddenly failing under immense force. Purdue researchers simulated this mechanism using 3D-printed versions of the blades. Credit: Purdue University/Maryam Hosseini and Pablo Zavattieri

First, the interconnecting blades lock to prevent themselves from pulling out of the suture like puzzle pieces. Second, the suture and blades delaminate, which leads to a more graceful deformation that mitigates catastrophic failure of the exoskeleton. Each strategy dissipates energy to circumvent a fatal impact at the neck, where the beetle’s exoskeleton is most likely to fracture.

Even if a maximum force is applied to the beetle’s exoskeleton, delamination allows the interconnecting blades to pull out from the suture more gently. If the blades were to interlock too much or too little, the sudden release of energy would cause the beetle’s neck to snap.

It’s not yet known if the diabolical ironclad beetle has a way to heal itself after surviving a car “accident.” But knowing about these strategies could already solve fatigue problems in various kinds of machinery.

“An active engineering challenge is joining together different materials without limiting their ability to support loads. The diabolical ironclad beetle has strategies to circumvent these limitations,” said David Restrepo, an assistant professor at the University of Texas at San Antonio who worked on this project as a postdoctoral researcher in Zavattieri’s group.

In the gas turbines of aircraft, for example, metals and composite materials are joined together with a mechanical fastener. This fastener adds weight and introduces stress that could lead to fractures and corrosion.

“These fasteners ultimately decrease the performance of the system and need to be replaced every so often. But the interfacial sutures of the diabolical ironclad beetle provide a robust and more predictable failure that could help solve these problems,” said Maryam Hosseini, who worked on this project as a Ph.D. student and postdoctoral researcher in Zavattieri’s group. Hosseini is now an engineering manager at Procter & Gamble Corp.

UCI researchers built a carbon fiber composite fastener mimicking a diabolical ironclad beetle’s suture. Purdue researchers found through loading tests that this fastener is just as strong as a standard aerospace fastener, but significantly tougher.

“This work shows that we may be able to shift from using strong, brittle materials to ones that can be both strong and tough by dissipating energy as they break. That’s what nature has enabled the diabolical ironclad beetle to do,” Zavattieri said.

Reference: 21 October 2020, Nature.
DOI: 10.1038/s41586-020-2813-8

This research is financially supported by the Air Force Office of Scientific Research and the Army Research Office through the Multi-University Research Initiative (award number FA9550-15-1-0009). The study used resources at the Advanced Light Source, a U.S. Department of Energy Office of Science User Facility.

Gene editing for the development of new treatments, and for studying disease as well as normal function in humans and other organisms, may advance more quickly with a new tool for cutting larger pieces of DNA out of a cell’s genome, according to a new study by UC San Francisco scientists.

Publication of the UCSF study on October 19, 2020, in the journal Nature Methods comes less than two weeks after two researchers who first used the genetic scissors known as CRISPR-Cas9 were selected to receive this year’s Nobel Prize in Chemistry.

Though now employed as a research tool in laboratories around the world, CRISPR evolved eons ago in bacteria as a means to fight their ancient nemeses, a whole host of viruses known as bacteriophages. When bacteria encounter a phage, they incorporate a bit of the viral DNA into their own DNA, and it then serves as a template to make RNA that binds to the corresponding viral DNA in the phage itself. The CRISPR enzymes then target, disable, and kill the phage.

In his latest work exploring this ancient and strange arms race, principal investigator Joseph Bondy-Denomy, PhD, associate professor in the UCSF Department of Microbiology and Immunology, joined scientists Bálint Csörgő, PhD, and Lina León to develop and test a new CRISPR tool.

The already renowned CRISPR-Cas9 ensemble is like a molecular chisel that can be used to rapidly and precisely excise a small bit of DNA at a targeted site. Other methods can then be used to insert new DNA. But the new CRISPR-Cas3 system adapted by the UCSF scientists employs a different bacterial immune system. The key enzyme in this system, Cas3, acts more like a molecular wood chipper to remove much longer stretches of DNA quickly and accurately.

“Cas3 is like Cas9 with a motor — after finding its specific DNA target, it runs on DNA and chews it up like a Pac-Man,” Bondy-Denomy said.

This new capability to delete or replace long stretches of DNA will enable researchers to more efficiently assess the importance of genomic regions that contain DNA sequences of indeterminate function, according to Bondy-Denomy, an important consideration in understanding humans and the pathogens that plague them.

“Previously, there was no easy and reliable way to delete very large regions of DNA in bacteria for research or therapeutic purposes,” he said. “Now, instead of making 100 different small DNA deletions we can just make one deletion and ask, ‘What changed?’”

Because bacteria and other types of cells are commonly used to produce small molecule or protein-based pharmaceuticals, CRISPR-Cas3 will enable biotechnology industry scientists to more easily remove potentially pathogenic or useless DNA from these cells, according to Bondy-Denomy.

“Large swathes of bacterial DNA are poorly understood, with unknown functions that in some cases are not necessary for survival,” Bondy-Denomy said. “In addition, bacterial DNA contains large stretches of DNA imported from other sources, which can cause disease in the bacterium’s human host, or divert bacterial metabolism.”

CRISPR-Cas3 also should also allow entire genes to be inserted into the genome in industrial, agricultural or even in human gene therapy applications, Bondy-Denomy said.

The UCSF researchers selected and modified the CRISPR-Cas3 system used by the bacterium Pseudomonas aeruginosa, and demonstrated in this species and in three others, including bacteria that cause disease in humans and plants, that their more compact version functions well to remove selected DNA in all four species. Other CRISPR-Cas3 systems have been made to work in human and other mammalian cells, and that also should be achievable for the modified P. aeruginosa system, Bondy-Denomy said.

Bondy-Denomy studies a range of bacteria, bacteriophage, and CRISPR systems to learn more about how they work and to find useful molecular tools. “CRISPR-Cas3 is by far the most common CRISPR system in nature,” he said. “About 10 times as many bacterial species use a Cas3 system as use a Cas9 system. It may be that Cas3 is a better bacterial immune system because it shreds phage DNA.”

Unlike Cas9, when Cas3 binds to its precise DNA target it begins chewing up one strand of the double-stranded DNA in both directions, leaving a single strand exposed. The deletions obtained in the UCSF experiments ranged in size, in many cases encompassing as many as 100 bacterial genes. The CRISPR-Cas3 mechanism should also allow for easier replacement of deleted DNA with a new DNA sequence, the researchers found.

For DNA deletion and editing in the lab, scientists program CRISPR systems to target specific DNA in the genome of an organism of interest using any guide sequence they choose.

In the new CRISPR-Cas3 study, by manipulating the sequences of DNA provided to the bacteria for repairing the deletions, the researchers were able to precisely set the boundaries of these large DNA repairs, something they were unable to accomplish with CRISPR-Cas9.

Bondy-Denomy previously discovered anti-CRISPR strategies that phage evolved to fight back against bacteria, and these might prove useful for stopping the gene editing reactions driven by Cas enzymes used as human therapeutics before side effects arise, or in using phage to remove unwanted bacteria that have populated the gut, he said. Apart from E. coli and a couple of other species, relatively little is known about the 1,000 or so bacterial species that normally reside there.

“Non-model microbes have largely been left behind in the genetics world, and there is a huge need for new tools to study them,” he said.

Reference: “A compact Cascade–Cas3 system for targeted genome engineering” by Bálint Csörgő, Lina M. León, Ilea J. Chau-Ly, Alejandro Vasquez-Rifo, Joel D. Berry, Caroline Mahendra, Emily D. Crawford, Jennifer D. Lewis and Joseph Bondy-Denomy, 19 October 2020, Nature Methods.
DOI: 10.1038/s41592-020-00980-w

Authors: Bondy-Denomy is senior author. Postdoctoral fellow Csörgő and graduate student León co-led this work, collaborating with other UCSF authors including Joel Berry, Caroline Mahendra and Emily Crawford.

Funding: The work was primarily funded by UCSF Program for Breakthrough Biomedical Research, the Innovative Genomics Institute, and an National Institutes of Health Director’s Early Independence Award to Bondy-Denomy.

Disclosures: Bondy-Denomy is a scientific advisory board member of SNIPR Biome and Excision Biotherapeutics and a scientific advisory board member and cofounder of Acrigen Biosciences. UCSF has filed a patent application relating to various aspects of Cas3-based genome editing.

Lily the barn owl demonstrates wing-morphing to cope with gusts in flight. Credit: Cheney et al 2020

Scientists from the University of Bristol and the Royal Veterinary College have discovered how birds are able to fly in gusty conditions — findings that could inform the development of bio-inspired small-scale aircraft.

“Birds routinely fly in high winds close to buildings and terrain — often in gusts as fast as their flight speed. So the ability to cope with strong and sudden changes in wind is essential for their survival and to be able to do things like land safely and capture prey,” said Dr. Shane Windsor from the Department of Aerospace Engineering at the University of Bristol.

“We know birds cope amazingly well in conditions which challenge engineered air vehicles of a similar size but, until now, we didn’t understand the mechanics behind it,” said Dr. Windsor.

The study, published in Proceedings of the Royal Society B, reveals how bird wings act as a suspension system to cope with changing wind conditions. The team used an innovative combination of high-speed, video-based 3D surface reconstruction, computed tomography (CT) scans, and computational fluid dynamics (CFD) to understand how birds ‘reject’ gusts through wing morphing, i.e. by changing the shape and posture of their wings.

In the experiment, conducted in the Structure and Motion Laboratory at the Royal Veterinary College, the team filmed Lily, a barn owl, gliding through a range of fan-generated vertical gusts, the strongest of which was as fast as her flight speed. Lily is a trained falconry bird who is a veteran of many nature documentaries, so wasn’t fazed in the least by all the lights and cameras.

“We began with very gentle gusts in case Lily had any difficulties, but soon found that — even at the highest gust speeds we could make — Lily was unperturbed; she flew straight through to get the food reward being held by her trainer, Lloyd Buck,” commented Professor Richard Bomphrey of the Royal Veterinary College.

“Lily flew through the bumpy gusts and consistently kept her head and torso amazingly stable over the trajectory, as if she was flying with a suspension system. When we analyzed it, what surprised us was that the suspension-system effect wasn’t just due to aerodynamics, but benefited from the mass in her wings. For reference, each of our upper limbs is about 5% of our body weight; for a bird it’s about double, and they use that mass to effectively absorb the gust,” said lead-author Dr. Jorn Cheney from the Royal Veterinary College.

“Perhaps most exciting is the discovery that the very fastest part of the suspension effect is built into the mechanics of the wings, so birds don’t actively need to do anything for it to work. The mechanics are very elegant. When you strike a ball at the sweet spot of a bat or racquet, your hand is not jarred because the force there cancels out. Anyone who plays a bat-and-ball sport knows how effortless this feels. A wing has a sweet spot, just like a bat. Our analysis suggests that the force of the gust acts near this sweet spot and this markedly reduces the disturbance to the body during the first fraction of a second. The process is automatic and buys just enough time for other clever stabilizing processes to kick in,” added Dr Jonathan Stevenson from the University of Bristol.

Dr. Windsor said the next step for the research, which was funded by the European Research Council (ERC), Air Force Office of Scientific Research, and the Wellcome Trust, is to develop bio-inspired suspension systems for small-scale aircraft.

Reference: “Bird wings act as a suspension system that rejects gusts” by Jorn A. Cheney, Jonathan P. J. Stevenson, Nicholas E. Durston, Jialei Song, James R. Usherwood, Richard J. Bomphrey and Shane P. Windsor,  21 October 2020, Proceedings of the Royal Society B.
DOI: 10.1098/rspb.2020.1748

Imagine a mobile phone charger that doesn’t need a wireless or main power source. Or a pacemaker with inbuilt organic energy sources within the human body.

Australian researchers led by Flinders University are picking up the challenge of ‘scavenging’ invisible power from low-frequency vibrations in the surrounding environment, including wind, air, or even contact-separation energy (static electricity).

“These so-called triboelectric nanogenerators (or ‘TENGs’) can be made at low cost in different configurations, making them suitable for driving small electronics such as personal electronics (mobile phones), biomechanics devices (pacemakers), sensors (temperature/pressure/chemical sensors), and more,” says Professor Youhong Tang, from Flinders University’s College of Science and Engineering.

Further research aims to further develop this renewable form of energy harvesting by designing simple fabrication from cheap and sustainable materials, with high efficiency.

PhD candidate Mohammad Khorsand and Professor Youhong Tang with the TENG prototype at Flinders University, Tonsley Innovation District in Adelaide, South Australia. Credit: Flinders University

“They can use non-invasive materials, so could one day be used for implantable and wearable energy harvesting aims,” says Flinders Institute for NanoScale Science and Technology PhD candidate Mohammad Khorsand, co-lead author on recent papers in the international journal Nano Energy.

The latest paper uses AI-enhanced mathematical modeling to compare the function of the number of segments, rotational speed and tribo-surface spacing of an advanced TENG prototype to optimize the storage and performance.

The researchers, with colleagues at the University of Technology Sydney and elsewhere, are working to improve power generation of TENGs and store the generated power on supercapacitor or battery.

“We have been able to effectively harvest power from sliding movement and rotary motion which are abundantly available in our living environment,” says Professor Tang.

References:

“Artificial intelligence enhanced mathematical modeling on rotary triboelectric nanogenerators under various kinematic and geometric conditions” by Mohammad Khorsand, Javad Tavakoli, Haowen Guan and Youhong Tang, 30 May 2020, Nano Energy.
DOI: 10.1016/j.nanoen.2020.104993

“Simulation of high-output and lightweight sliding-mode triboelectric nanogenerators” by Mohammad Khorsand, Javad Tavakoli, Kudzai Kamanya and Youhong Tang, 14 September 2020, Nano Energy.
DOI: 10.1016/j.nanoen.2019.104115

Key points:

The first generation of triboelectric nanogenerators (TENGs) was fabricated at Georgia Institute of Technology in the US about 10 years ago. Research at Flinders University is aiming design cost effective and high-efficient sliding and rotary TENGs for further development and possible commercialization. This research on the next generation of TENG is using AI and simulation modeling to reduce the cost of repeating the experiment for various conditions. The research team is focusing on numerically predicting the outputs of TENGs by measuring their voltage, current, power and energy under various electric specifications and geometries of dielectric films.

This video clip shows a 3D printing technique where a printer head scans over each layer of a part, blowing metal powder which is melted by a laser. It’s one of several ways parts are 3D printed at NASA’s Jet Propulsion Laboratory, but was not used to create the parts aboard the Perseverance rover.

For hobbyists and makers, 3D printing expands creative possibilities; for specialized engineers, it’s also key to next-generation spacecraft design.

If you want to see science fiction at work, visit a modern machine shop, where 3D printers create materials in just about any shape you can imagine. NASA is exploring the technique – known as additive manufacturing when used by specialized engineers – to build rocket engines as well as potential outposts on the Moon and Mars. Nearer in the future is a different milestone: NASA’s Perseverance rover, which lands on the Red Planet on Feb. 18, 2021, carries 11 metal parts made with 3D printing.

Instead of forging, molding, or cutting materials, 3D printing relies on lasers to melt powder in successive layers to give shape to something. Doing so allows engineers to play with unique designs and traits, such as making hardware lighter, stronger, or responsive to heat or cold.

“It’s like working with papier-mâché,” said Andre Pate, the group lead for additive manufacturing at NASA’s Jet Propulsion Laboratory in Southern California. “You build each feature layer by layer, and soon you have a detailed part.”

Curiosity, Perseverance’s predecessor, was the first mission to take 3D printing to the Red Planet. It landed in 2012 with a 3D-printed ceramic part inside the rover’s ovenlike Sample Analysis at Mars (SAM) instrument. NASA has since continued to test 3D printing for use in spacecraft to make sure the reliability of the parts is well understood.

As “secondary structures,” Perseverance’s printed parts wouldn’t jeopardize the mission if they didn’t work as planned, but as Pate said, “Flying these parts to Mars is a huge milestone that opens the door a little more for additive manufacturing in the space industry.”

The outer shell of PIXL, one of the instruments aboard NASA’s Perseverance Mars rover, includes several parts that were made of 3D-printed titanium. The inset shows the front half of the two-piece shell part it was finished. Credit: NASA/JPL-Caltech

A Shell for PIXL

Of the 11 printed parts going to Mars, five are in Perseverance’s PIXL instrument. Short for the Planetary Instrument for X-ray Lithochemistry, the lunchbox-size device will help the rover seek out signs of fossilized microbial life by shooting X-ray beams at rock surfaces to analyze them.

PIXL shares space with other tools in the 88-pound (40-kilogram) rotating turret at the end of the rover’s 7-foot-long (2-meter-long) robotic arm. To make the instrument as light as possible, the JPL team designed PIXL’s two-piece titanium shell, a mounting frame, and two support struts that secure the shell to the end of the arm to be hollow and extremely thin. In fact, the parts, which were 3D printed by a vendor called Carpenter Additive, have three or four times less mass than if they’d been produced conventionally.

“In a very real sense, 3D printing made this instrument possible,” said Michael Schein, PIXL’s lead mechanical engineer at JPL. “These techniques allowed us to achieve a low mass and high-precision pointing that could not be made with conventional fabrication.”

This X-ray image shows the interior of a 3D-printed heat exchanger in Perseverance’s MOXIE instrument. X-ray images like these are used to check for defects within parts. Credit: NASA/JPL-Caltech

MOXIE Turns Up the Heat

Perseverance’s six other 3D-printed parts can be found in an instrument called the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE. This device will test technology that, in the future, could produce industrial quantities of oxygen to create rocket propellant on Mars, helping astronauts launch back to Earth.

To create oxygen, MOXIE heats Martian air up to nearly 1,500 degrees Fahrenheit (800 degrees Celsius). Within the device are six heat exchangers – palm-size nickel-alloy plates that protect key parts of the instrument from the effects of high temperatures.

While a conventionally machined heat exchanger would need to be made out of two parts and welded together, MOXIE’s were each 3D-printed as a single piece at nearby Caltech, which manages JPL for NASA.

“These kinds of nickel parts are called superalloys because they maintain their strength even at very high temperatures,” said Samad Firdosy, a material engineer at JPL who helped develop the heat exchangers. “Superalloys are typically found in jet engines or power-generating turbines. They’re really good at resisting corrosion, even while really hot.”

Although the new manufacturing process offers convenience, each layer of alloy that the printer lays down can form pores or cracks that can weaken the material. To avoid this, the plates were treated in a hot isostatic press – a gas crusher – that heats material to over 1,832 degrees Fahrenheit (1,000 degrees Celsius) and adds intense pressure evenly around the part. Then, engineers used microscopes and lots of mechanical testing to check the microstructure of the exchangers and ensure they were suitable for spaceflight.

“I really love microstructures,” Firdosy said. “For me to see that kind of detail as material is printed, and how it evolves to make this functional part that’s flying to Mars – that’s very cool.”

More About the Mission

A key objective of Perseverance’s mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent missions, currently under consideration by NASA in cooperation with ESA (the European Space Agency), would send spacecraft to Mars to collect these cached samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 mission is part of a larger program that includes missions to the Moon as a way to prepare for human exploration of the Red Planet. Charged with returning astronauts to the Moon by 2024, NASA will establish a sustained human presence on and around the Moon by 2028 through NASA’s Artemis lunar exploration plans.

JPL, which is managed for NASA by Caltech in Pasadena, Southern California, built and manages operations of the Perseverance and Curiosity rovers.

Penn State College of Medicine researchers say certain oral antiseptics and mouthwashes may have the ability to inactivate human coronaviruses. They say clinical trials needed to determine if these products can reduce the amount of virus COVID-19 positive patients spread when talking, sneezing, or coughing.

Certain oral antiseptics and mouthwashes may have the ability to inactivate human coronaviruses, according to a Penn State College of Medicine research study. The results indicate that some of these products might be useful for reducing the viral load, or amount of virus, in the mouth after infection and may help to reduce the spread of SARS-CoV-2, the coronavirus that causes COVID-19.

Craig Meyers, distinguished professor of microbiology and immunology and obstetrics and gynecology, led a group of physicians and scientists who tested several oral and nasopharyngeal rinses in a laboratory setting for their ability to inactivate human coronaviruses, which are similar in structure to SARS-CoV-2. The products evaluated include a 1% solution of baby shampoo, a neti pot, peroxide sore-mouth cleansers, and mouthwashes.

The researchers found that several of the nasal and oral rinses had a strong ability to neutralize human coronavirus, which suggests that these products may have the potential to reduce the amount of virus spread by people who are COVID-19-positive.

“While we wait for a vaccine to be developed, methods to reduce transmission are needed,” Meyers said. “The products we tested are readily available and often already part of people’s daily routines.”

Meyers and colleagues used a test to replicate the interaction of the virus in the nasal and oral cavities with the rinses and mouthwashes. Nasal and oral cavities are major points of entry and transmission for human coronaviruses. They treated solutions containing a strain of human coronavirus, which served as a readily available and genetically similar alternative for SARS-CoV-2, with the baby shampoo solutions, various peroxide antiseptic rinses and various brands of mouthwash. They allowed the solutions to interact with the virus for 30 seconds, one minute and two minutes, before diluting the solutions to prevent further virus inactivation. According to Meyers, the outer envelopes of the human coronavirus tested and SARS-CoV-2 are genetically similar so the research team hypothesizes that a similar amount of SARS-CoV-2 may be inactivated upon exposure to the solution.

To measure how much virus was inactivated, the researchers placed the diluted solutions in contact with cultured human cells. They counted how many cells remained alive after a few days of exposure to the viral solution and used that number to calculate the amount of human coronavirus that was inactivated as a result of exposure to the mouthwash or oral rinse that was tested. The results were published in the Journal of Medical Virology.

The 1% baby shampoo solution, which is often used by head and neck doctors to rinse the sinuses, inactivated greater than 99.9% of human coronavirus after a two-minute contact time. Several of the mouthwash and gargle products also were effective at inactivating the infectious virus. Many inactivated greater than 99.9% of virus after only 30 seconds of contact time and some inactivated 99.99% of the virus after 30 seconds.   

According to Meyers, the results with mouthwashes are promising and add to the findings of a study showing that certain types of oral rinses could inactivate SARS-CoV-2 in similar experimental conditions. In addition to evaluating the solutions at longer contact times, they studied over-the-counter products and nasal rinses that were not evaluated in the other study. Meyers said the next step to expand upon these results is to design and conduct clinical trials that evaluate whether products like mouthwashes can effectively reduce viral load in COVID-19-positive patients.

“People who test positive for COVID-19 and return home to quarantine may possibly transmit the virus to those they live with,” said Meyers, a researcher at Penn State Cancer Institute. “Certain professions including dentists and other health care workers are at a constant risk of exposure. Clinical trials are needed to determine if these products can reduce the amount of virus COVID-positive patients or those with high-risk occupations may spread while talking, coughing or sneezing. Even if the use of these solutions could reduce transmission by 50%, it would have a major impact.”

Future studies may include a continued investigation of products that inactive human coronaviruses and what specific ingredients in the solutions tested inactivate the virus.

Reference: “Lowering the transmission and spread of human coronavirus” by Craig Meyers, PhD; Richard Robison, PhD; Janice Milici, BS; Samina Alam, PhD; David Quillen, MD; David Goldenberg, MD, FACS and Rena Kass, MD, 17 September 2020, Journal of Medical Virology.
DOI: 10.1002/jmv.26514

Janice Milici, Samina Alam, David Quillen, David Goldenberg and Rena Kass of Penn State College of Medicine and Richard Robison of Brigham Young University also contributed to this research.

The research was supported by funds from Penn State Huck Institutes for the Life Sciences. The researchers declare no conflict of interest.

First study to use objective measure to look at 25,000 people’s diet.

People who consume a diet including flavanol-rich foods and drinks, including tea, apples, and berries, could lead to lower blood pressure, according to the first study using objective measures of thousands of UK residents’ diet.

The findings, published in Scientific Reports, studied the diet of more than 25,000 people in Norfolk, UK and compared what they ate with their blood pressure. In contrast to most other studies investigating links between nutrition and health, the researchers did not rely on study participants reporting their diet, but instead measured flavanol intake objectively using nutritional biomarkers — indicators of dietary intake, metabolism or nutritional status that are present in our blood.

The difference in blood pressure between those with the lowest 10% of flavanol intake and those with the highest 10% of intake was between 2 and 4 mmHg. This is comparable to meaningful changes in blood pressure observed in those following a Mediterranean diet or Dietary Approaches to Stop Hypertension (DASH) diet. Notably, the effect was more pronounced in participants with hypertension.

Professor Gunter Kuhnle, a nutritionist at the University of Reading who led the study said:

“Previous studies of large populations have always relied on self-reported data to draw conclusions, but this is the first epidemiological study of this scale to objectively investigate the association between a specific bioactive compound and health. We are delighted to see that in our study, there was also a meaningful and significant association between flavanol consumption and lower blood pressure.

“What this study gives us is an objective finding about the association between flavanols — found in tea and some fruits — and blood pressure. This research confirms the results from previous dietary intervention studies and shows that the same results can be achieved with a habitual diet rich in flavanols. In the British diet, the main sources are tea, cocoa, apples, and berries.

“The methodology of the study is of equal importance. This is one of the largest ever studies to use nutritional biomarkers to investigate bioactive compounds. Using nutritional biomarkers to estimate intake of bioactive food compounds has long been seen as the gold standard for research, as it allows intake to be measured objectively. The development, validation, and application of the biomarker was only possible because of the long-term commitment of all collaborators. In contrast to self-reported dietary data, nutritional biomarkers can address the huge variability in food composition. We can therefore confidently attribute the associations we observed to flavanol intake.”

An international team from the University of Reading, Cambridge University, the University of California Davis, and Mars, Incorporated studied 25,618 participants from the European Prospective Investigation into Cancer (EPIC) Norfolk study and found that the biggest difference was observed in participants with the highest blood pressure. This suggests if the general public increased its flavanol intake, there could be an overall reduction in cardiovascular disease incidence.

Hagen Schroeter, Chief Science Officer at Mars Edge, said:

“This study adds key insights to a growing body of evidence supporting the benefits of dietary flavanols in health and nutrition. But, perhaps even more exciting was the opportunity to apply objective biomarkers of flavanol intake at a large scale. This enabled the team to avoid the significant limitations that come with past approaches which rely on estimating intake based on self-reported food consumption data and the shortcomings of current food composition databases.”

Reference: 21 October 2020, Scientific Reports.
DOI: 10.1038/s41598-020-74863-7

The study was supported with an unrestricted grant from Mars, Incorporated, and two co-authors are employees of Mars. The study worked with the EPIC Norfolk population cohort, which acknowledges funding from the Medical Research Council and Cancer Research UK.

In developing a system to help decipher lost languages, MIT researchers studied the language of Ugaritic, which is related to Hebrew and has previously been analyzed and deciphered by linguists.
Credit: S.R.K. Branavan

System developed at MIT CSAIL aims to help linguists decipher languages that have been lost to history.

Recent research suggests that most languages that have ever existed are no longer spoken. Dozens of these dead languages are also considered to be lost, or “undeciphered” — that is, we don’t know enough about their grammar, vocabulary, or syntax to be able to actually understand their texts.

Lost languages are more than a mere academic curiosity; without them, we miss an entire body of knowledge about the people who spoke them. Unfortunately, most of them have such minimal records that scientists can’t decipher them by using machine-translation algorithms like Google Translate. Some don’t have a well-researched “relative” language to be compared to, and often lack traditional dividers like white space and punctuation. (To illustrate, imaginetryingtodecipheraforeignlanguagewrittenlikethis.)

However, researchers at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) recently made a major development in this area: a new system that has been shown to be able to automatically decipher a lost language, without needing advanced knowledge of its relation to other languages. They also showed that their system can itself determine relationships between languages, and they used it to corroborate recent scholarship suggesting that the language of Iberian is not actually related to Basque.

The team’s ultimate goal is for the system to be able to decipher lost languages that have eluded linguists for decades, using just a few thousand words.

Spearheaded by MIT Professor Regina Barzilay, the system relies on several principles grounded in insights from historical linguistics, such as the fact that languages generally only evolve in certain predictable ways. For instance, while a given language rarely adds or deletes an entire sound, certain sound substitutions are likely to occur. A word with a “p” in the parent language may change into a “b” in the descendant language, but changing to a “k” is less likely due to the significant pronunciation gap.

By incorporating these and other linguistic constraints, Barzilay and MIT PhD student Jiaming Luo developed a decipherment algorithm that can handle the vast space of possible transformations and the scarcity of a guiding signal in the input. The algorithm learns to embed language sounds into a multidimensional space where differences in pronunciation are reflected in the distance between corresponding vectors. This design enables them to capture pertinent patterns of language change and express them as computational constraints. The resulting model can segment words in an ancient language and map them to counterparts in a related language.  

The project builds on a paper Barzilay and Luo wrote last year that deciphered the dead languages of Ugaritic and Linear B, the latter of which had previously taken decades for humans to decode. However, a key difference with that project was that the team knew that these languages were related to early forms of Hebrew and Greek, respectively.

With the new system, the relationship between languages is inferred by the algorithm. This question is one of the biggest challenges in decipherment. In the case of Linear B, it took several decades to discover the correct known descendant. For Iberian, the scholars still cannot agree on the related language: Some argue for Basque, while others refute this hypothesis and claim that Iberian doesn’t relate to any known language. 

The proposed algorithm can assess the proximity between two languages; in fact, when tested on known languages, it can even accurately identify language families. The team applied their algorithm to Iberian considering Basque, as well as less-likely candidates from Romance, Germanic, Turkic, and Uralic families. While Basque and Latin were closer to Iberian than other languages, they were still too different to be considered related. 

In future work, the team hopes to expand their work beyond the act of connecting texts to related words in a known language — an approach referred to as “cognate-based decipherment.” This paradigm assumes that such a known language exists, but the example of Iberian shows that this is not always the case. The team’s new approach would involve identifying semantic meaning of the words, even if they don’t know how to read them. 

“For instance, we may identify all the references to people or locations in the document which can then be further investigated in light of the known historical evidence,” says Barzilay. “These methods of ‘entity recognition’ are commonly used in various text processing applications today and are highly accurate, but the key research question is whether the task is feasible without any training data in the ancient language.”

The project was supported, in part, by the Intelligence Advanced Research Projects Activity (IARPA).

(l-r) Jonny Wu, assistant professor of geology in the UH Department of Earth and Atmospheric Sciences and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era. Credit: University of Houston

Long-debated plate located in Northern Canada using 3D mapping technology.

The existence of a tectonic plate called Resurrection has long been a topic of debate among geologists, with some arguing it was never real. Others say it subducted – moved sideways and downward – into the earth’s mantle somewhere in the Pacific Margin between 40 and 60 million years ago.

A team of geologists at the University of Houston College of Natural Sciences and Mathematics believes they have found the lost plate in northern Canada by using existing mantle tomography images – similar to a CT scan of the earth’s interior. The findings, published in Geological Society of America Bulletin, could help geologists better predict volcanic hazards as well as mineral and hydrocarbon deposits.

A 3D block diagram across North America showing a mantle tomography image reveals the Slab Unfolding method used to flatten the Farallon tectonic plate. By doing this, Fuston and Wu were able to locate the lost Resurrection plate. Credit: Spencer Fuston and Jonny Wu, University of Houston Dept. of Earth and Atmospheric Sciences in the College of Natural Sciences and Mathematics

“Volcanoes form at plate boundaries, and the more plates you have, the more volcanoes you have,” said Jonny Wu, assistant professor of geology in the Department of Earth and Atmospheric Sciences. “Volcanoes also affect climate change. So, when you are trying to model the earth and understand how climate has changed since time, you really want to know how many volcanoes there have been on earth.”

Wu and Spencer Fuston, a third-year geology doctoral student, applied a technique developed by the UH Center for Tectonics and Tomography called slab unfolding to reconstruct what tectonic plates in the Pacific Ocean looked like during the early Cenozoic Era. The rigid outermost shell of Earth, or lithosphere, is broken into tectonic plates and geologists have always known there were two plates in the Pacific Ocean at that time called Kula and Farallon. But there has been discussion about a potential third plate, Resurrection, having formed a special type of volcanic belt along Alaska and Washington State.

A 3D block diagram across North America showing a mantle tomography image reveals the Slab Unfolding method used to flatten the Farallon tectonic plate. By doing this, Fuston and Wu were able to locate the lost Resurrection plate. Credit: Spencer Fuston and Jonny Wu, University of Houston Dept. of Earth and Atmospheric Sciences in the College of Natural Sciences and Mathematics

“We believe we have direct evidence that the Resurrection plate existed. We are also trying to solve a debate and advocate for which side our data supports,” Fuston said.

Using 3D mapping technology, Fuston applied the slab unfolding technique to the mantle tomography images to pull out the subducted plates before unfolding and stretching them to their original shapes.

“When ‘raised’ back to the earth’s surface and reconstructed, the boundaries of this ancient Resurrection tectonic plate match well with the ancient volcanic belts in Washington State and Alaska, providing a much sought after link between the ancient Pacific Ocean and the North American geologic record,” explained Wu.

Reference: “Raising the Resurrection plate from an unfolded-slab plate tectonic reconstruction of northwestern North America since early Cenozoic time” by Spencer Fuston and Jonny Wu, 19 October 2020, GSA Bulletin.
DOI: 10.1130/B35677.1

This study is funded by a five-year, $568,309 National Science Foundation CAREER Award led by Wu.

Note: Animation below shows the subduction of Kula, Farallon and Resurrection tectonic plates in western North America 60 million years ago to present day.