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New glove-like device mimics sense of touch

What if you could touch a loved one during a video call — particularly in today’s social distancing era of COVID-19 — or pick up and handle a virtual tool in a video game?

Pending user tests and funding to commercialise the new technology, these ideas could become reality in a couple of years after UNSW Sydney engineers developed a new haptic device which recreates the sense of touch.

Haptic technology mimics the experience of touch by stimulating localised areas of the skin in ways that are similar to what is felt in the real world, through force, vibration or motion.

Dr Thanh Nho Do, Scientia Lecturer and UNSW Medical Robotics Lab director, is senior author of a study featuring the new device.

His research team featured lead author and PhD candidate Mai Thanh Thai, Phuoc Thien Phan, Trung Thien Hoang and collaborator Scientia Professor Nigel Lovell, Head of the Graduate School of Biomedical Engineering.

Dr Do said the sense of touch was something many people took for granted to perform everyday tasks.

“When we do things with our hands, such as holding a mobile phone or typing on a keyboard, all of these actions are impossible without haptics,” he said.

“The human hand has a high density of tactile receptors and is both an interesting and challenging area to encode information through haptic stimulation, because we use our hands to perceive most objects every day.

“There are many situations where the sense of touch would be useful but is impossible: for example, in a telehealth consultation a doctor is unable to physically examine a patient. So, we aimed to solve this problem.”

The UNSW study about the new haptic device was published in the Institute of Electrical and Electronics Engineers (IEEE) Access journal recently.

Dr Do said the researchers were so excited about their new haptic technology that they had applied to patent it.

“Our three-way directional skin stretch device (SSD), built into the fingertips of the wearable haptic glove we also created, is like wearing a second skin — it’s soft, stretchable and mimics the sense of touch — and will enable new forms of haptic communication to enhance everyday activities,” he said.

“What’s also special about our new technology is that it’s scalable and can be integrated into textiles for use in various potential applications such as telehealth, medical devices, surgical robots and training, augmented and virtual reality, teleoperation and industrial settings.

“The device aims to solve a common problem in emerging systems — such as assistive devices, remote surgery, self-driving cars and the guidance of human movements — where visual or auditory feedback can be slow, unintuitive and increase the cognitive load.”

Why haptic technology needs to improve

The study’s lead author Mai Thanh Thai said existing technology had great difficulty recreating the sense of touch with objects in virtual environments or located remotely.

“Visual or auditory cues are easy to replicate, but haptic cues are more challenging to reproduce. In a virtual environment, we can see objects but we are unable to feel them as if we were directly touching them,” Mr Thai said.

“It is almost impossible to enable a user to feel something happening in a computer or smartphone using a haptic interface, such as commercially available smart glasses.

“Vibration is the most common haptic technology today and is built into many electronic devices, such as the Taptic Engine attached to the back of a trackpad in laptops, which simulates a button clicking.

“But haptic feedback with vibration becomes less sensitive when used continuously or when users are in motion, leading to desensitisation and impaired device functionality.”

How the new haptic device works

Dr Do said the researchers’ new technology overcame issues with existing haptic devices by introducing a novel method to recreate an effective haptic sensation via soft, miniature artificial “muscles.”

“Our soft, wearable haptic glove enables people to feel virtual or remote objects in a more realistic and immersive way. The inbuilt soft artificial muscles generate sufficient normal and shear forces to the user’s fingertips via a soft tactor, enabling them to effectively reproduce the sense of touch,” he said.

“It works like this: imagine you are in Australia while your friend is in the United States. You wear a haptic glove with our integrated three-way directional SSDs in the fingertips and your friend also wears a glove with integrated 3D force sensors.

“If your friend picks up an object, it will physically press against your friend’s fingers and their glove with 3D force sensors will measure these interactions.

“If these 3D force signals are sent to your haptic glove, then the integrated three-way directional SSDs will generate these exact 3D forces at your fingertips, enabling you to experience the same sense of touch as your friend.”

Implications of the new technology

Dr Do said the ability to effectively reproduce the sense of touch via the new wearable haptic device would have a wide range of benefits; for example, during today’s COVID-19 pandemic when people were relying on video calls to stay connected with loved ones.

“Unlike existing haptic devices, our technology is soft, lightweight, and thin and therefore, we hope users will be able to integrate it into what they’re wearing to provide realistic haptic experiences in settings including rehabilitation, education, training and recreation,” he said.

“Our technology could enable a user to feel objects inside a virtual world or at a distance; for example, a scientist could feel a virtual rock from another planet without leaving their lab, or a surgeon could feel a patient’s organ tissues with surgical tools without directly touching them.”

Dr Do estimated the new technology could become available in the next 18 months to three years — if plans to commercialise the device were realised.

“The next step is to conduct user evaluations to validate how effective our device is, because the main scope of our current research has been on the design, fabrication and characterisation of the new technology,” he said.

“In addition, we plan to implement the device in various haptic applications such as haptic motion guidance, navigational assistance for older people and those with low vision, tactile textual language, and 3D force feedback display for use in surgical robots, prosthesis and virtual and augmented reality.”

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ScienceDaily

The widespread footprint of blue jean microfibers

With many people working from home during the COVID-19 pandemic, blue jeans are a more popular wardrobe choice than ever. But most people don’t think about microscopic remnants of their comfy jeans and other clothing that are shed during laundering. Now, researchers reporting in ACS’ Environmental Science & Technology Letters have detected indigo denim microfibers not only in wastewater effluent, but also in lakes and remote Arctic marine sediments.

Over the past 100 years, the popularity of denim blue jeans has grown immensely, with many people wearing this type of clothing almost every day. Studies have shown that washing denim and other fabrics releases microfibers — tiny, elongated particles — to wastewater. Although most microfibers are removed by wastewater treatment plants, some could still enter the environment through wastewater discharge, also known as effluent. Blue jean denim is composed of natural cotton cellulose fibers, processed with synthetic indigo dye and other chemical additives to improve performance and durability. Miriam Diamond, Samantha Athey and colleagues wondered whether blue jeans were a major source of anthropogenic cellulose microfibers to the aquatic environment.

The researchers used a combination of microscopy and Raman spectroscopy to identify and count indigo denim microfibers in various water samples collected in Canada. Indigo denim made up 23, 12 and 20% of all microfibers in sediments from the Great Lakes, shallow suburban lakes near Toronto, Canada, and the Canadian Arctic Archipelago, respectively. Despite a high abundance of denim microfibers in Great Lake sediments, the team detected only a single denim microfiber in the digestive tract of a type of fish called rainbow smelt. Based on the levels of microfibers found in wastewater effluent, the researchers estimated that the wastewater treatment plants in the study discharged about 1 billion indigo denim microfibers per day. In laundering experiments, the researchers found that a single pair of used jeans could release about 50,000 microfibers per wash cycle. Although the team doesn’t know the effects, if any, that the microfibers have on aquatic life, a practical way to reduce denim microfiber pollution would be for consumers to wash their jeans less frequently, they say. Moreover, finding microfibers from blue jeans in the Arctic is a potent indicator of humans’ impact on the environment, the researchers add.

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ScienceDaily

Evidence supports ‘hot start’ scenario and early ocean formation on Pluto

The accretion of new material during Pluto’s formation may have generated enough heat to create a liquid ocean that has persisted beneath an icy crust to the present day, despite the dwarf planet’s orbit far from the sun in the cold outer reaches of the solar system.

This “hot start” scenario, presented in a paper published June 22 in Nature Geoscience, contrasts with the traditional view of Pluto’s origins as a ball of frozen ice and rock in which radioactive decay could have eventually generated enough heat to melt the ice and form a subsurface ocean.

“For a long time people have thought about the thermal evolution of Pluto and the ability of an ocean to survive to the present day,” said coauthor Francis Nimmo, professor of Earth and planetary sciences at UC Santa Cruz. “Now that we have images of Pluto’s surface from NASA’s New Horizons mission, we can compare what we see with the predictions of different thermal evolution models.”

Because water expands when it freezes and contracts when it melts, the hot-start and cold-start scenarios have different implications for the tectonics and resulting surface features of Pluto, explained first author and UCSC graduate student Carver Bierson.

“If it started cold and the ice melted internally, Pluto would have contracted and we should see compression features on its surface, whereas if it started hot it should have expanded as the ocean froze and we should see extension features on the surface,” Bierson said. “We see lots of evidence of expansion, but we don’t see any evidence of compression, so the observations are more consistent with Pluto starting with a liquid ocean.”

The thermal and tectonic evolution of a cold-start Pluto is actually a bit complicated, because after an initial period of gradual melting the subsurface ocean would begin to refreeze. So compression of the surface would occur early on, followed by more recent extension. With a hot start, extension would occur throughout Pluto’s history.

“The oldest surface features on Pluto are harder to figure out, but it looks like there was both ancient and modern extension of the surface,” Nimmo said.

The next question was whether enough energy was available to give Pluto a hot start. The two main energy sources would be heat released by the decay of radioactive elements in the rock and gravitational energy released as new material bombarded the surface of the growing protoplanet.

Bierson’s calculations showed that if all of the gravitational energy was retained as heat, it would inevitably create an initial liquid ocean. In practice, however, much of that energy would radiate away from the surface, especially if the accretion of new material occurred slowly.

“How Pluto was put together in the first place matters a lot for its thermal evolution,” Nimmo said. “If it builds up too slowly, the hot material at the surface radiates energy into space, but if it builds up fast enough the heat gets trapped inside.”

The researchers calculated that if Pluto formed over a period of less that 30,000 years, then it would have started out hot. If, instead, accretion took place over a few million years, a hot start would only be possible if large impactors buried their energy deep beneath the surface.

The new findings imply that other large Kuiper belt objects probably also started out hot and could have had early oceans. These oceans could persist to the present day in the largest objects, such as the dwarf planets Eris and Makemake.

“Even in this cold environment so far from the sun, all these worlds might have formed fast and hot, with liquid oceans,” Bierson said.

In addition to Bierson and Nimmo, the paper was coauthored by Alan Stern at the Southwest Research Institute, the principal investigator of the New Horizons mission.

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New study provides maps, ice favorability index to companies looking to mine the moon

The 49ers who panned for gold during California’s Gold Rush didn’t really know where they might strike it rich. They had word of mouth and not much else to go on.

Researchers at the University of Central Florida want to give prospectors looking to mine the moon better odds of striking gold, which on the moon means rich deposits of water ice that can be turned into resources, like fuel, for space missions.

A team lead by planetary scientist Kevin Cannon created an Ice Favorability Index. The geological model explains the process for ice formation at the poles of the moon, and mapped the terrain, which includes craters that may hold ice deposits. The model, which has been published in the peer-reviewed journal Icarus, accounts for what asteroid impacts on the surface of the moon may do to deposits of ice found meters beneath the surface.

“Despite being our closest neighbor, we still don’t know a lot about water on the moon, especially how much there is beneath the surface,” Cannon says. “It’s important for us to consider the geologic processes that have gone on to better understand where we may find ice deposits and how to best get to them with the least amount of risk.”

The team was inspired by mining companies on Earth, which conduct detailed geological work, and take core samples before investing in costly extraction sites. Mining companies conduct field mappings, take core samples from the potential site and try to understand the geological reasons behind the formation of the particular mineral they are looking for in an area of interest. In essence they create a model for what a mining zone might look like before deciding to plunk down money to drill.

The team at UCF followed the same approach using data collected about the moon over the years and ran simulations in the lab. While they couldn’t collect core samples, they had data from satellite observations and from the first trip to the moon.

Why Mine the Moon

In order for humans to explore the solar system and beyond, spacecraft have to be able to launch and continue on their long missions. One of the challenges is fuel. There are no gas stations in space, which means spacecraft have to carry extra fuel with them for long missions and that fuel weighs a lot. Mining the moon could result in creating fuel , which would help ease the cost of flights since spacecraft wouldn’t have to haul the extra fuel.

Water ice can be purified and processed to produce both hydrogen and oxygen for propellent, according to several previously published studies. Sometime in the future, this process could be completed on the moon effectively producing a gas station for spacecraft. Asteroids may also provide similar resources for fuel.

Some believe a system of these “gas stations” would be the start of the industrialization of space.

Several private companies are exploring mining techniques to employ on the moon. Both Luxembourg and the United States have adopted legislation giving citizens and corporations ownership rights over resources mined in space, including the moon, according to the study.

“The idea of mining the moon and asteroids isn’t science fiction anymore,” says UCF physics Professor and co-author Dan Britt. “There are teams around the world looking to find ways to make this happen and our work will help get us closer to making the idea a reality.”

The study was supported by NASA’s Solar System Exploration Research Virtual Institute cooperative agreement with the Center for Lunar and Asteroid Surface Science (CLASS) based at UCF.

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Hackster.io

Making Companion Bots // Virtually Maker Faire 2020

During the Covid-19 stay at home orders, a group of makers have been focusing on our personal robotic projects to help us through the isolation. For Virtually Maker Faire, we share our robots and explain a bit more about them and our prototyping process.

MEET THE BOTS:

Nova: a fluffy shoulder companion that lights up and reacts to touch. She is worn like a scarf and uses two servos to create movements that invite people to interact with her. Learn more about Nova on Angela’s Hackaday project page https://hackaday.io/project/169449-nova-a-companion-bot

Dexter: A high fiving fun monkey bot. He is fully 3D printed, with a PIR Sensor so he can sense when people are near and high five them. He also has animated led Eye Matrix for multiple emotions.
https://www.hackster.io/Odd_Jayy

Fenrir: Alex’s fennec fox with an AI heart. A new sibling for Archimedes (the owl familiar), Fen is designed to help with daily tasks including transcribing dreams, and experiments in defeating facial recognition technology.
https://www.hackster.io/glowascii

MEET THE MAKERS:

Alex Glow
Alex creates videos about electronics at Hackster.io, and shares projects including her robot owl familiar Archimedes, music that has orbited the Earth, and LED temporary tattoos. She loves to hack on robots, music, wearables, bikes, cults, language, hackerspaces, brains & dreaming, holography, and more. Find more at alexglow.com and @glowascii 🙂
https://twitter.com/glowascii/

Jorvon Moss
Jorvon Moss, Odd_Jayy friends call me Jayy. I am a Maker, Tinker from Compton, I Have been featured in Hackspace Magazine, Done talks at both Maker Faire, and Hackaday Supercon. I have built multiple companion bots, to keep up with me work follow me on twitter or instagram.

https://www.instagram.com/odd_jayy/

Angela Sheehan
Angela (Gella) is a maker, artist, and educator passionate about wearable technology, product design, and digital fabrication. She has published over 50 online how-tos and loves to teach others how to make playful and interactive electronic projects. See all her projects at Gellacraft.com and connect with her on Twitter @the_gella.

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ScienceDaily

Pofatu: A new database for geochemical ‘fingerprints’ of artefacts

Due to the improvement and increased use of geochemical fingerprinting techniques during the last 25 years, the archaeological compositional data of stone tools has grown exponentially. The Pofatu Database is a large-scale collaborative project that enables curation and data sharing. The database also provides instrumental details, analytical procedures and reference standards used for calibration purposes or quality control. Thus, Pofatu ensures reproducibility and comparability between provenance studies.

Provenance studies (documenting where artefacts are found relative to their sources or place of manufacture) help archaeologists understand the “life-histories” of artefacts, in this case, stone tools. They show where the raw material come from and how artefacts were manufactured and distributed between individuals and groups. Reliable data allows scientists to reconstruct technological, economic, and social behaviors of human societies over many thousands of years.

To facilitate access to this growing body of geochemical data, Aymeric Hermann and Robert Forkel of the Department for Linguistic and Cultural Evolution, Max Planck Institute for the Science of Human History, conceived and designed Pofatu, the first open-access database of geochemical compositions and contextual information for archaeological sources and artefacts in a form readily accessible to the scientific community.

Reconstructing ancient strategies of raw material and artefact procurement

Geochemical “fingerprinting” of artefacts is the most effective way to reconstruct how and where ancient peoples extracted, transformed, and exchanged stone materials and artefacts. These fingerprints also serve as clues to understand a number of phenomenon in past human societies, such as technical and economic behaviors, as well as sociopolitical organizations.

The Pofatu Database provides researchers with access to an ever-expanding dataset and facilitates comparability and reproducibility in provenance studies. Each sample is comprehensively documented for elemental and isotopic compositions, and includes detailed archaeological provenance, as well as supporting analytical metadata, such as sampling processes, analytical procedures, and quality control.

“By providing analytical data and comprehensive archaeological details in a form that can be readily accessed by the scientific community,” Hermann says, “the Pofatu Database will facilitate assigning unambiguous provenance to artefacts in future studies and will lead to more robust, large-scope modelling of long-distance voyaging and traditional exchange systems.”

Additionally, Marshall Weisler, a collaborator in the Pofatu project from the University of Queensland in Australia, stated that “By tracing the transport of artefacts carried across the wide expanse of the Pacific Ocean, we will be able to reconstruct the ancient journeys enabling the greatest maritime migration in human history.”

Pofatu — an operational framework for data sharing in archaeometry

Pofatu’s structure was designed by Forkel and Hermann. Hermann compiled and described the data with contributions and validations by colleagues and co-authors from universities and research institutions in New Zealand, Australia, and the USA. The database uses GitHub for open-source storage and version control and common non-proprietary file formats (CSV) to enable transparency and built-in reproducibility for future studies of prehistoric exchange. The database currently contains 7759 individual samples from archaeological sites and geological sources across the Pacific Islands, but Pofatu is made for even more, Hermann notes.

“With Pofatu we activated an operational framework for data sharing in archaeometry. The database is currently focused on sites and collections from the Pacific Islands, but we welcome all contributions of geochemical data on archaeological material, regardless of geographic or chrono-cultural boundaries. Our vision is an inclusive and collaborative data resource that will hopefully continue to develop with more datasets from the Pacific as well as from other regions. The ultimate goal is a more global project contemporary to other existing online repositories for geological materials.”

Although the Pofatu Database is meant to be used primarily by archaeologists, analyses of geological samples and raw material extracted from prehistoric quarries could also be used by geologists to gather essential information on the smaller or more remote Pacific islands, which are among the least studied places on the planet and sometimes lack geochemical documentation. In that sense, Pofatu is a tool that will facilitate interdisciplinary research.

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Cold War nuke tests changed rainfall

Nuclear bomb tests during the Cold War may have changed rainfall patterns thousands of miles from the detonation sites, new research has revealed.

Scientists at the University of Reading have researched how the electric charge released by radiation from the test detonations, carried out predominantly by the US and Soviet Union in the 1950s and 1960s, affected rainclouds at the time.

The study, published in Physical Review Letters, used historic records between 1962-64 from a research station in Scotland. Scientists compared days with high and low radioactively-generated charge, finding that clouds were visibly thicker, and there was 24% more rain on average on the days with more radioactivity.

Professor Giles Harrison, lead author and Professor of Atmospheric Physics at the University of Reading, said: “By studying the radioactivity released from Cold War weapons tests, scientists at the time learnt about atmospheric circulation patterns. We have now reused this data to examine the effect on rainfall.

“The politically charged atmosphere of the Cold War led to a nuclear arms race and worldwide anxiety. Decades later, that global cloud has yielded a silver lining, in giving us a unique way to study how electric charge affects rain.”

It has long been thought that electric charge modifies how water droplets in clouds collide and combine, potentially affecting the size of droplets and influencing rainfall, but this is difficult to observe in the atmosphere. By combining the bomb test data with weather records, the scientists were able to retrospectively investigate this.

Through learning more about how charge affects non-thunderstorm clouds, it is thought that scientists will now have a better understanding of important weather processes.

The race to develop nuclear weapons was a key feature of the Cold War, as the world’s superpowers sought to demonstrate their military capabilities during heightened tensions following the Second World War.

Although detonations were carried out in remote parts of the world, such as the Nevada Desert in the US, and on Pacific and Arctic islands, radioactive pollution spread widely throughout the atmosphere. Radioactivity ionises the air, releasing electric charge.

The researchers, from the Universities of Reading, Bath and Bristol, studied records from well-equipped Met Office research weather stations at Kew near London and Lerwick in the Shetland Isles.

Located 300 miles north west of Scotland, the Shetland site was relatively unaffected by other sources of anthropogenic pollution. This made it well suited as a test site to observe rainfall effects which, although likely to have occurred elsewhere too, would be much more difficult to detect.

Atmospheric electricity is most easily measured on fine days, so the Kew measurements were used to identify nearly 150 days where there was high or low charge generation over the UK while it was cloudy in Lerwick. The Shetland rainfall on these days showed differences which vanished after the major radioactivity episode was over.

The findings may be helpful for cloud-related geoengineering research, which is exploring how electric charge could influence rain, relieve droughts or prevent floods, without the use of chemicals.

Professor Harrison is leading a project investigating electrical effects on dusts and clouds in the United Arab Emirates, as part of their national programme in Rain Enhancement Science. These new findings will help to show the typical charges possible in natural non-thunderstorm clouds.

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ProgrammableWeb

These COVID-19 APIs Have Drawn the Most Developer Interest

Since February, ProgrammableWeb has been following the COVID-19 outbreak. During that time we have tried to keep our readers up to date on new resources being made available to developers who want to join the fight against the pandemic. For example, to support developer efforts, over 60 COVID-19 related APIs have been released along with all kinds of open-source code, data sets, and other tools. You can visit our COVID-19 Developer Resource Center to learn more.

One question that has arisen is which APIs have gained the most traction with developers. Every API in the ProgrammableWeb directory offers a tracking capability that notifies developers of any relevant updates (new versions, news, etc.) through a weekly personalized Watchlist. This functionality extends to all directory content including SDKs, Sample Code, Libraries, and Frameworks. Entire categories can also be tracked. If a reader is interested in the COVID-19 category, for example, they can track it to receive weekly notifications that will tell them about new content that has been added to the category — including directory assets and news stories — or updates to existing content.

On the ProgrammableWeb side of things, this tracking data gives us insight into the APIs that our readers are most interested in. With that in mind, we looked at which COVID-19 related APIs have the most followers. There are currently 68 APIs tagged with the COVID-19 category, these are the top five in terms of followers.

NovelCOVID – This RESTful API is an open-source collaboration hosted on GitHub. It is a free API that returns the current information about the COVID-19 outbreak. The API supports country-specific responses and allows queries on the following parameters: cases, today’s cases, deaths, today’s deaths, recovered, and critical. You can read our full coverage of this API.

Bing COVID-19 Data – The Bing COVID-19 Data API provides total confirmed cases, deaths, and recoveries by country. Data is sourced from the US Centers for Disease Control and Prevention (CDC), World Health Organization (WHO), and the European Centre for Disease Prevention and Control (ECDC). The API is used as a source for a live map tracker from Microsoft Bing.

COVID19INDIA  – This API is part of a volunteer-driven, crowdsourced database project for COVID-19 stats and patient tracing in India. The API returns daily confirmed cases, daily deceased cases, and daily recovered cases as time-series data. This information is also available cumulatively and per district. 

About Corona COVID-19 – The About Corona COVID-19 API provides a RESTful interface that allows users to query data from The World Health Organization Situation Reports, the Johns Hopkins University Center for Systems Science and Engineering (JHU CSSE), The U.S. Department of Health & Human Services, The National Health Commission of the People’s Republic of China, the ECDC, and the Chinese Centre for Disease Control and Prevention (CCDC).

This API retrieves data by country including population, the number of confirmed cases, recovered cases, critical cases, deaths, recovered cases per death ratio, cases per million population, and more. The data is updated multiple times a day.

Nubentos COVID-19 Tracking – This API is from the self-proclaimed API marketplace for health, and it aims to provide valuable resources for tracking the COVID-19 outbreak. It provides developers access to data collected from global health organizations and local administrations including the WHO, the CDC, the CCDC, China’s National Health Commission, and the Chinese Website DXY. We covered this API in March.

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ScienceDaily

Lung-heart super sensor on a chip tinier than a ladybug

During a stroll, a woman’s breathing becomes a slight bit shallower, and a monitor in her clothing alerts her to get a telemedicine check-up. A new study details how a sensor chip smaller than a ladybug records multiple lung and heart signals along with body movements and could enable such a future socially distanced health monitor.

The core mechanism of the chip developed by researchers at the Georgia Institute of Technology involves two finely manufactured layers of silicon, which overlay each other separated by the space of 270 nanometers — about 0.005 the width of a human hair. They carry a minute voltage.

Vibrations from bodily motions and sounds put part of the chip in flux, making the voltage flux, too, thus creating readable electronic outputs. In human testing, the chip has recorded a variety of signals from the mechanical workings of the lungs and the heart with clarity, signals that often escape meaningful detection by current medical technology.

“Right now, medicine looks to EKGs (electrocardiograms) for information on the heart, but EKGs only measure electrical impulses. The heart is a mechanical system with muscles pumping and valves opening and shutting, and it sends out a signature of sounds and motions, which an EKG does not detect. EKGs also say nothing about lung function,” said Farrokh Ayazi, Ken Byers Professor in Georgia Tech’s School of Electrical and Computer Engineering.

Stethoscope-accelerometer combo

The chip, which acts as an advanced electronic stethoscope and accelerometer in one, is aptly called an accelerometer contact microphone. It detects vibrations that enter the chip from inside the body while keeping out distracting noise from outside the body’s core like airborne sounds

“If it rubs on my skin or shirt, it doesn’t hear the friction, but the device is very sensitive to sounds coming at it from inside the body, so it picks up useful vibrations even through clothing,” Ayazi said.

The detection bandwidth is enormous — from broad, sweeping motions to inaudibly high-pitched tones. Thus, the sensor chip records all at once fine details of the heartbeat, pulse waves traversing the body’s tissues, respiration rates, and lung sounds. It even tracks the wearer’s physical activities such as walking.

The signals are recorded in sync, potentially offering the big picture of a patient’s heart and lung health. For the study, the researchers successfully recorded a “gallop,” a faint third sound after the “lub-dub” of the heartbeat. Gallops are normally elusive clues of heart failure.

The researchers published their results in the journal npj Digital Medicine on February 12, 2020. The research was funded by the Georgia Research Alliance, the Defense Advanced Research Projects Agency (DARPA), the National Science Foundation, and the National Institutes of Health. Study coauthor Divya Gupta, M.D., a cardiologist at Emory University, collaborated in testing the chip on human participants.

Hermetically sealed vacuum

Medical research has tried to make better use of the body’s mechanical signals for decades but recording some — like waves traversing multiple tissues — has proven inconsistent, while others — like gallops — have relied upon clinician skills influenced by human error. The new chip produces high-resolution, quantified data that future research could match to pathologies in order to identify them.

“We are working already to collect significantly more data matched with pathologies. We envision algorithms in the future that may enable a broad array of clinical readings,” Ayazi said.

Though the chip’s main engineering principle is simple, making it work and then manufacturable took Ayazi’s lab ten years, mainly because of the Lilliputian scale of the gap between the silicon layers, i.e. electrodes. If the 2-millimeter by 2-millimeter sensor chip were expanded to the size of a football field, that air gap would be about an inch wide.

“That very thin gap separating the two electrodes cannot have any contact, not even by forces in the air in between the layers, so the whole sensor is hermetically sealed inside a vacuum cavity,” Ayazi said. “This makes for that ultralow signal noise and breadth of bandwidth that are unique.”

Detects through clothing

The researchers used a manufacturing process developed in Ayazi’s lab called the HARPSS+ platform (High Aspect Ratio Poly and Single Crystalline Silicon) for mass production, running off hand-sized sheets that were then cut into the tiny sensor chips. HARPSS+ is the first reported mass manufacturing process that achieves such consistently thin gaps, and it has enabled high-throughput manufacturing of many such advanced MEMS, or microelectromechanical systems.

The experimental device is currently battery-powered and uses a second chip called a signal-conditioning circuit to translate the sensor chip’s signals into patterned read-outs.

Three sensors or more could be inserted into a chest band that would triangulate health signals to locate their sources. Someday a device may pinpoint an emerging heart valve flaw by turbulence it produces in the bloodstream or identify a cancerous lesion by faint crackling sounds in a lung.

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Cold War nuclear bomb tests reveal true age of whale sharks

Atomic bomb tests conducted during the Cold War have helped scientists for the first time correctly determine the age of whale sharks.

The discovery, published in the journal Frontiers in Marine Science, will help ensure the survival of the species — the largest fish in the world — which is classified as endangered.

Measuring the age of whale sharks (Rhincodon typus) has been difficult because, like all sharks and rays, they lack bony structures called otoliths that are used to assess the age of other fish.

Whale shark vertebrae feature distinct bands — a little like the rings of a tree trunk — and it was known that these increased in number as the animal grew older. However, some studies suggested that a new ring was formed every year, while others concluded that it happened every six months.

To resolve the question, researchers led by researchers led by Joyce Ong from Rutgers University in New Jersey, USA, Steven Campana from the University of Iceland, and Mark Meekan from the Australian Institute of Marine Science in Perth, Western Australia, turned to the radioactive legacy of the Cold War’s nuclear arms race.

During the 1950s and 1960s, the USA, Soviet Union, Great Britain, France and China conducted tests of nuclear weapons. Many of these were explosions detonated several kilometres in the air.

One powerful result of the blasts was the temporary atmospheric doubling of an isotope called carbon-14.

Carbon-14 is a naturally occurring radioactive element that is often used by archaeologists and historians to date ancient bones and artefacts. Its rate of decay is constant and easily measured, making it ideal for providing age estimates for anything over 300 years old.

However, it is also a by-product of nuclear explosions. Fallout from the Cold War tests saturated first the air, and then the oceans. The isotope gradually moved through food webs into every living thing on the planet, producing an elevated carbon-14 label, or signature, which still persists.

This additional radioisotope also decays at a steady rate — meaning that the amount contained in bone formed at one point in time will be slightly greater than that contained in otherwise identical bone formed more recently.

Using bomb radiocarbon data prepared by Steven Campana, Ong, Meekan, and colleagues set about testing the carbon-14 levels in the growth rings of two long-dead whale sharks stored in Pakistan and Taiwan. Measuring the radioisotope levels in successive growth rings allowed a clear determination of how often they were created — and thus the age of the animal.

“We found that one growth ring was definitely deposited every year,” Dr Meekan said.

“This is very important, because if you over- or under-estimate growth rates you will inevitably end up with a management strategy that doesn’t work, and you’ll see the population crash.”

One of the specimens was conclusively established as 50 years old at death — the first time such an age has been unambiguously verified.

“Earlier modelling studies have suggested that the largest whale sharks may live as long as 100 years,” Dr Meekan said.

“However, although our understanding of the movements, behaviour, connectivity and distribution of whale sharks have improved dramatically over the last 10 years, basic life history traits such as age, longevity and mortality remain largely unknown.

“Our study shows that adult sharks can indeed attain great age and that long lifespans are probably a feature of the species. Now we have another piece of the jigsaw added.”

Whale sharks are today protected across their global range and are regarded as a high-value species for eco-tourism. AIMS is the world’s leading whale shark research body, and the animal is the marine emblem of Dr Meekan’s home state, Western Australia.

Drs Ong, Meekan, and Campana were aided by Dr Hua Hsun Hsu from the King Fahd University of Petroleum and Minerals in Saudi Arabia, and Dr Paul Fanning from the Pakistan node of the UN Food and Agricultural Organisation.

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