Tuesday, July 7, 2020

The Sixth Sense of Animals: An Early Warning System for Earthquakes?





Continuously observing animals with motion sensors could improve earthquake prediction

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Even today, nobody can reliably predict when and where an earthquake will occur. However, eyewitnesses have repeatedly reported that animals behave unusually before an earthquake. In an international cooperation project, researchers from the Max Planck Institute of Animal Behavior in Konstanz/Radolfzell and the Cluster of Excellence Centre for the Advanced Study of Collective Behaviour at the University of Konstanz, have investigated whether cows, sheep, and dogs can actually detect early signs of earthquakes. To do so, they attached sensors to the animals in an earthquake-prone area in Northern Italy and recorded their movements over several months. The movement data show that the animals were unusually restless in the hours before the earthquakes. The closer the animals were to the epicentre of the impending quake, the earlier they started behaving unusually. The movement profiles of different animal species in different regions could therefore provide clues with respect to the place and time of an impending earthquake.

Damage following an earthquake in northern Italy.

© MPIAB/ MaxCine

Experts disagree about whether earthquakes can be exactly predicted. Nevertheless, animals seem to sense the impending danger hours in advance. For example, there are reports that wild animals leave their sleeping and nesting places immediately before strong quakes and that pets become restless. However, these anecdotal accounts often do not stand up to scientific scrutiny because the definition of unusual behaviour is often too unclear and the observation period too short. Other factors could also explain the behaviour of the animals.

In order to be able to use animal activity patterns as a kind of early warning system for earthquakes, the animals would have to show measurable behavioural changes. Moreover, if they do indeed react to weak physical changes immediately before an earthquake, they should react more strongly the closer they are to the epicentre of the quake.

Animals with movement sensors


A cow with a motion sensor at the neck (front).

© MPIAB/ MaxCine

In an international cooperation project, researchers from the Max Planck Institute of Animal Behavior in Radolfzell/Konstanz and the Centre for the Advanced Study of Collective Behaviour, a Cluster of Excellence at the University of Konstanz, have investigated whether animals really do this. On an Italian farm in an earthquake-prone area, they attached accelerometers to the collars of six cows, five sheep, and two dogs that had already displayed unusual behaviour before earthquakes. The researchers then recorded their movements continuously over several months. During this period, official authorities reported about 18,000 earthquakes in the region. In addition to many small and hardly noticeable quakes, there were also 12 earthquakes with a strength of 4 or higher on the Richter scale.

The researchers then selected the quakes that triggered statistically relevant earth movements on the farm. These included strong quakes up to 28 km away as well as weaker quakes, the epicentres of which were very close to the farm. However, instead of explicitly looking for abnormal behaviours in the period before these events, the researchers chose a more cautious approach. They first marked all behavioural changes of the animals that were unusual according to objective, statistical criteria. “In this way, we ensure that we not only establish correlations retrospectively but also that we really do have a model that can be used for predictions,” says Martin Wikelski, director at the Max Planck Institute of Animal Behavior and Principal Investigator at the Centre for the Advanced Study of Collective Behaviour.

The data—measured as body acceleration of each farm animal (indicating activity level)—were evaluated using statistical models drawn from financial econometrics. “Because every animal reacts differently in size, speed and according to species, the animal data resemble data on heterogenous financial investors,” explains co-author Winfried Pohlmeier, Professor of Econometrics at the University of Konstanz and Principal Investigator at the Centre for the Advanced Study of Collective Behaviour. The scientists also considered other disturbance factors such as natural changes in animal activity patterns over the day.

Unusual behavioural patterns


Elephants can also show unusual movement patterns before earthquakes.

© MPIAB/ MaxCine

In this way, the researchers discovered unusual behavioural patterns up to 20 hours before an earthquake. “The closer the animals were to the epicentre of the impending shock, the earlier they changed their behaviour. This is exactly what you would expect when physical changes occur more frequently at the epicentre of the impending earthquake and become weaker with increasing distance,” explains Wikelski. However, this effect was clear only when the researchers looked at all animals together. “Collectively, the animals seem to show abilities that are not so easily recognized on an individual level,” says Wikelski. It is still unclear how animals can sense impending earthquakes. Animals may sense the ionization of the air caused by the large rock pressures in earthquake zones with their fur. It is also conceivable that animals can smell gases released from quartz crystals before an earthquake.

Real-time data measured by the researchers and recorded since December 2019 show what an animal earthquake early warning system could look like: a chip on the collar sends the movement data to a central computer every three minutes. This triggers a warning signal if it registers a significantly increased activity of the animals for at least 45 minutes. The researchers have once received such a warning. “Three hours later, a small quake shook the region,” says Wikelski. “The epicentre was directly below the stables of the animals.”

However, before the behaviour of animals can be used to predict earthquakes, researchers need to observe a larger number of animals over longer periods of time in different earthquake zones around the world. For this, they want to use the global animal observation system Icarus on the International Space Station ISS, which will start its scientific operation in a few weeks.

Icarus, a scientific project directed by Martin Wikelski, is a joint project funded and carried out by the German Aerospace Center (DLR) and the Russian space agency Roskosmos and is supported by the European Space Agency (ESA).


Contacts and sources:
Dr. Martin Wikelski Max Planck Institute of Animal Behavior, Radolfzell / Konstanz
Uschi Müller Project Coordinator Icarus Max Planck Institute of Animal Behavior, Radolfzell / Konstanz


Publication: Potential short-term earthquake forecasting by farm-animal monitoring. Martin Wikelski, Uschi Mueller, Paola Scocco, Andrea Catorci, Lev Desinov, Mikhail Belyaev, Daniel Keim, Winfried Pohlmeier, Gerhard Fechteler, P. Martin Mai
Ethology; 3 July, 2020
Source

Passive Stretching Helps Improve Blood Flow


New research published in The Journal of Physiology shows that 12 weeks of easy–to–administer passive stretching helps improve blood flow by making it easier for your arteries to dilate and decreasing their stiffness.

Passive stretching differs from active stretching in that the former involves an external force (another person or gravity) stretching you, whereas active stretching is performed on your own. The changes they observed in blood vessels could have implications for diseases, including the number one global killer, heart disease. 
Credit: Yathin S Krishnappa / Wikimedia Commons

Researchers at the University of Milan assigned 39 healthy participants of both sexes to two groups. The control group didn’t undergo any stretching. The experimental group performed leg stretches 5 times a week for 12 weeks. Researchers evaluated the effect of passive stretching on the blood flow locally and in the upper arm. They found that the arteries in both the lower leg and upper arm had increased blood flow and dilation when stimulated, along with decreased stiffness.

Both of these changes may have implications for diseases such as heart disease, stroke and diabetes as they are characterized by changes in blood flow control, due to an impaired vascular system.

If this study is replicated in patients with vascular disease, it could indicate whether or not this training method could serve as a new drug-free treatment for improving vascular health and reducing disease risk, especially in people with lower mobility.

Moreover, stretching may also be used during hospitalization or after surgical interventions, in order to preserve the vascular health when patients have low mobility. It can be also performed at home by carers or family members.

Emiliano Ce, an author on the paper said: “This new application of stretching is especially relevant in the current pandemic period of increased confinement to our homes, where the possibility of performing beneficial training to improve and prevent heart disease, stroke and other conditions is limited.”

The Journal of Physiology publishes advances in physiology which increase our understanding of how our bodies function in health and disease. http://jp.physoc.org 
 
The Physiological Society brings together over 4,000 scientists from over 60 countries. The Society promotes physiology with the public and parliament alike. It supports physiologists by organising world-class conferences and offering grants for research and also publishes the latest developments in the field in its three leading scientific journals, The Journal of Physiology, Experimental Physiology and Physiological Reports. www.physoc.org



Contacts and sources:
Julia Turan
The Physiological Society


Publication: Evidence for improved systemic and local vascular function after long‐term passive static stretching training of the musculoskeletal system A. V. Bisconti, E. Cè, S. Longo, M. Venturelli, G. Coratella, E. Limonta, C. Doria, S. Rampichini, F. Esposito. . The Journal of Physiology, 2020; DOI: 10.1113/JP279866



Ancient Monster Penguins had Northern Hemisphere Doppelgangers



New Zealand’s monster penguins that lived 62 million years ago had doppelgangers in Japan, the USA and Canada, a study published in the Journal of Zoological Systematics and Evolutionary Research has found.

Plotopterids like these Copepteryx looked remarkably like penguins.


 Image: Mark Witton. Available for media and current affairs use; all other rights reserved

Scientists have identified striking similarities between the penguins’ fossilised bones and those of a group of much younger Northern Hemisphere birds, the plotopterids.

These similarities suggest plotopterids and ancient penguins looked very similar and might help scientists understand how birds started using their wings to swim instead of fly.

Around 62 million years ago, the earliest known penguins swam in tropical seas that almost submerged the land that is now New Zealand. Palaeontologists have found the fossilised bones of these ancient waddlers at Waipara, North Canterbury. They have identified nine different species, ranging in size from small penguins, the size of today’s Yellow-Eyed Penguin, to 1.6 metre-high monsters.

Plotopterids developed in the Northern Hemisphere much later than penguins, with the first species appearing between 37 and 34 million years ago. Their fossils have been found at a number of sites in North America and Japan. Like penguins, they used their flipper-like wings to swim through the sea. Unlike penguins, which have survived into the modern era, the last plotopterid species became extinct around 25 million years ago.

The scientists – Dr Gerald Mayr of the Senckenberg Research Institute and Natural History Museum, Frankfurt; James Goedert of the Burke Museum of Natural History and Culture and University of Washington, USA; and Canterbury Museum Curators Dr Paul Scofield and Dr Vanesa De Pietri – compared the fossilised bones of plotopterids with fossil specimens of the giant penguin species Waimanu, Muriwaimanu and Sequiwaimanu from Canterbury Museum’s collection.

They found plotopterids and the ancient penguins had similar long beaks with slit-like nostrils, similar chest and shoulder bones, and similar wings. These similarities suggest both groups of birds were strong swimmers that used their wings to propel them deep underwater in search of food.

Some species of both groups could grow to huge sizes. The largest known plotopterids were over 2 metres long, while some of the giant penguins were up to 1.6 metres tall.

The giant penguins, like these Kumimanu, that lived in Aotearoa New Zealand around 60 million years ago bore a striking resemblance to some plotopterids

Image: Mark Witton.  

Despite sharing a number of physical features with penguins both ancient and modern, plotopterids are more closely related to boobies, gannets and cormorants than they are to penguins.

“What’s remarkable about all this is that plotopterids and ancient penguins evolved these shared features independently,” says Dr De Pietri. “This is an example of what we call convergent evolution, when distantly related organisms develop similar morphological traits under similar environmental conditions.”

Dr Scofield says some large plotopterid species would have looked very similar to the ancient penguins. “These birds evolved in different hemispheres, millions of years apart, but from a distance you would be hard pressed to tell them apart,” he says. “Plotopterids looked like penguins, they swam like penguins, they probably ate like penguins – but they weren’t penguins.”

Dr Mayr says the parallels in the evolution of the bird groups hint at an explanation for why birds developed the ability to swim with their wings.

“Wing-propelled diving is quite rare among birds; most swimming birds use their feet. We think both penguins and plotodopterids had flying ancestors that would plunge from the air into the water in search of food. Over time these ancestor species got better at swimming and worse at flying."

Fossils from New Zealand’s giant penguins, including Waimanu and Sequiwaimanu are currently on display alongside life-sized models of the birds in Canterbury Museum’s exhibition Ancient New Zealand: Squawkzilla and the Giants, extended until 16 August.

Comparative osteology of the penguin-like mid Cenozoic Plotopteridae and the earliest true fossil penguins, with comment on the origins of wing-propelled diving, by Gerald Mayr, James L Goedert, Vanesa De Pietri and R Paul Scofield is published in the Journal of Zoological Systematics and Evolutionary Research. DOI: 10.1111/jzs.12400

This research was partly supported by the Royal Society of New Zealand’s Marsden Fund.




Contacts and source:
Canterbury Museum


Comparative osteology of the penguin‐like mid‐Cenozoic Plotopteridae and the earliest true fossil penguins, with comments on the origins of wing‐propelled diving.
Gerald Mayr, James L. Goedert, Vanesa L. De Pietri, R. Paul Scofield. Journal of Zoological Systematics and Evolutionary Research, 2020; DOI: 10.1111/jzs.12400
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White Dwarfs Reveal New Insights into The Origin of Carbon in The Universe

A new analysis of white dwarf stars supports their role as a key source of carbon, an element crucial to all life, in the Milky Way and other galaxies.

Approximately 90 percent of all stars end their lives as white dwarfs, very dense stellar remnants that gradually cool and dim over billions of years. With their final few breaths before they collapse, however, these stars leave an important legacy, spreading their ashes into the surrounding space through stellar winds enriched with chemical elements, including carbon, newly synthesized in the star’s deep interior during the last stages before its death.

NGC 7789, also known as Caroline's Rose, is an old open star cluster of the Milky Way, which lies about 8,000 light-years away toward the constellation Cassiopeia. It hosts a few white dwarfs of unusually high mass that were analyzed in this study. 
star-cluster-450.jpg
Image credit: Guillaume Seigneuret and NASA

Every carbon atom in the universe was created by stars, through the fusion of three helium nuclei. But astrophysicists still debate which types of stars are the primary source of the carbon in our own galaxy, the Milky Way. Some studies favor low-mass stars that blew off their envelopes in stellar winds and became white dwarfs, while others favor massive stars that eventually exploded as supernovae.

In the new study, published July 6 in Nature Astronomy, an international team of astronomers discovered and analyzed white dwarfs in open star clusters in the Milky Way, and their findings help shed light on the origin of the carbon in our galaxy. Open star clusters are groups of up to a few thousand stars, formed from the same giant molecular cloud and roughly the same age, and held together by mutual gravitational attraction. The study was based on astronomical observations conducted in 2018 at the W. M. Keck Observatory in Hawaii and led by coauthor Enrico Ramirez-Ruiz, professor of astronomy and astrophysics at UC Santa Cruz.

“From the analysis of the observed Keck spectra, it was possible to measure the masses of the white dwarfs. Using the theory of stellar evolution, we were able to trace back to the progenitor stars and derive their masses at birth,” explained Ramirez-Ruiz, who also holds a Niels Bohr Professorship at the University of Copenhagen.

The relationship between the initial masses of stars and their final masses as white dwarfs is known as the initial-final mass relation, a fundamental diagnostic in astrophysics that integrates information from the entire life cycles of stars, linking birth to death. In general, the more massive the star at birth, the more massive the white dwarf left at its death, and this trend has been supported on both observational and theoretical grounds.

But analysis of the newly discovered white dwarfs in old open clusters gave a surprising result: the masses of these white dwarfs were notably larger than expected, putting a “kink” in the initial-final mass relation for stars with initial masses in a certain range.

“Our study interprets this kink in the initial-final mass relationship as the signature of the synthesis of carbon made by low-mass stars in the Milky Way,” said lead author Paola Marigo at the University of Padua in Italy.

In the last phases of their lives, stars twice as massive as our Sun produced new carbon atoms in their hot interiors, transported them to the surface, and finally spread them into the interstellar medium through gentle stellar winds. The team’s detailed stellar models indicate that the stripping of the carbon-rich outer mantle occurred slowly enough to allow the central cores of these stars, the future white dwarfs, to grow appreciably in mass.

Analyzing the initial-final mass relation around the kink, the researchers concluded that stars bigger than 2 solar masses also contributed to the galactic enrichment of carbon, while stars of less than 1.5 solar masses did not. In other words, 1.5 solar masses represents the minimum mass for a star to spread carbon-enriched ashes upon its death.

These findings place stringent constraints on how and when carbon, the element essential to life on Earth, was produced by the stars of our galaxy, eventually ending up trapped in the raw material from which the Sun and its planetary system were formed 4.6 billion years ago.

“Now we know that the carbon came from stars with a birth mass of not less than roughly 1.5 solar masses,” said Marigo.

Coauthor Pier-Emmanuel Tremblay at University of Warwick said, “One of most exciting aspects of this research is that it impacts the age of known white dwarfs, which are essential cosmic probes to understand the formation history of the Milky Way. The initial-to-final mass relation is also what sets the lower mass limit for supernovae, the gigantic explosions seen at large distances and that are really important to understand the nature of the universe.”

By combining the theories of cosmology and stellar evolution, the researchers concluded that bright carbon-rich stars close to their death, quite similar to the progenitors of the white dwarfs analyzed in this study, are presently contributing to a vast amount of the light emitted by very distant galaxies. This light, carrying the signature of newly produced carbon, is routinely collected by large telescopes to probe the evolution of cosmic structures. A reliable interpretation of this light depends on understanding the synthesis of carbon in stars.

In addition to Marigo, Tremblay, and Ramirez-Ruiz, the coauthors of the paper include scientists at Johns Hopkins University, American Museum of Natural History in New York, Columbia University, Space Telescope Science Institute, University of Warwick, University of Montreal, University of Uppsala, International School for Advanced Studies in Trieste, Italian National Institute for Astrophysics, and the University of Geneva. This research was supported by the European Union through an ERC Consolidator Grant and the DNRF through a Niels Bohr Professorship.


Contacts and sources:
Tim Stephens
University of California - Santa Cruz.


Publication: Carbon star formation as seen through the non-monotonic initial–final mass relation.
Paola Marigo, Jeffrey D. Cummings, Jason Lee Curtis, Jason Kalirai, Yang Chen, Pier-Emmanuel Tremblay, Enrico Ramirez-Ruiz, Pierre Bergeron, Sara Bladh, Alessandro Bressan, Léo Girardi, Giada Pastorelli, Michele Trabucchi, Sihao Cheng, Bernhard Aringer, Piero Dal Tio. Nature Astronomy, 2020; DOI: 10.1038/s41550-020-1132-1





New Room-Temperature Liquid-Metal Battery Could Be the Path to Powering the Future



Researchers in the Cockrell School of Engineering at The University of Texas at Austin have built a new type of battery that combines the many benefits of existing options while eliminating their key shortcomings and saving energy.

Most batteries are composed of either solid-state electrodes, such as lithium-ion batteries for portable electronics, or liquid-state electrodes, including flow batteries for smart grids. The UT researchers have created what they call a “room-temperature all-liquid-metal battery,” which includes the best of both worlds of liquid- and solid-state batteries.

Solid-state batteries feature significant capacity for energy storage, but they typically encounter numerous problems that cause them to degrade over time and become less efficient. Liquid-state batteries can deliver energy more efficiently, without the long-term decay of sold-state devices, but they either fall short on high energy demands or require significant resources to constantly heat the electrodes and keep them molten.

The metallic electrodes in the team’s battery can remain liquefied at a temperature of 20 degrees Celsius (68 degrees Fahrenheit), the lowest operating temperature ever recorded for a liquid-metal battery, according to the researchers. This represents a major change, because current liquid-metal batteries must be kept at temperatures above 240 degrees Celsius.
Credit: University of Texas - Austin


“This battery can provide all the benefits of both solid- and liquid-state — including more energy, increased stability and flexibility — without the respective drawbacks, while also saving energy,” said Yu Ding, a postdoctoral researcher in associate professor Guihua Yu’s research group in the Walker Department of Mechanical Engineering. Ding is the lead author of a paper on the room-temperature battery the team published recently in Advanced Materials.

The battery includes a sodium-potassium alloy as the anode and a gallium-based alloy as the cathode. In the paper, the researchers note that it may be possible to create a battery with even lower melting points using different materials.

The room-temperature battery promises more power than today’s lithium-ion batteries, which are the backbone of most personal electronics. It can charge and deliver energy several times faster, the researchers said.

Because of the liquid components, the battery can be scaled up or down easily, depending on the power needed. The bigger the battery, the more power it can deliver. That flexibility allows these batteries to potentially power everything from smartphones and watches to the infrastructure underpinning the movement toward renewable energy.

“We are excited to see that liquid metal could provide a promising alternative to replace conventional electrodes,” Professor Yu said. “Given the high energy and power density demonstrated, this innovative cell could be potentially implemented for both smart grid and wearable electronics.”

The researchers have spent more than three years on this project, but the job isn’t done yet. Many of the elements that constitute the backbone of this new battery are more abundant than some of the key materials in traditional batteries, making them potentially easier and less expensive to produce on a large scale. However, gallium remains an expensive material. Finding alternative materials that can deliver the same performance while reducing the cost of production remains a key challenge.


Credit: University of Texas - Austin

The next step to increasing the power of the room-temperature battery comes in improving the electrolytes — the components that allow the electrical charge to flow through the battery.

“Although our battery cannot compete with high-temperature, liquid-metal batteries at the current stage, better power capability is expected if advanced electrolytes are designed with high conductivity,” Ding said.







Contacts and sources
:Nat Levy
Cockrell School of Engineering
University of Texas - Austin



Publication: Room‐Temperature All‐Liquid‐Metal Batteries Based on Fusible Alloys with Regulated Interfacial Chemistry and Wetting Yu Ding Xuelin Guo Yumin Qian Leigang Xue Andrei Dolocan Guihua Yu https://onlinelibrary.wiley.com/doi/abs/10.1002/adma.202002577 http://dx.doi.org/10.1002/adma.202002577







Earth's Magnetic Field Changes 10X Faster Than Previously Thought



A new study reveals that changes in the direction of the Earth’s magnetic field may take place 10 times faster than previously thought.


The study by the University of Leeds and University of California at San Diego, gives new insight into the swirling flow of iron 2,800 kilometres below the planet’s surface and how it has influenced the movement of the magnetic field during the past 100,000 years.

Earth's magnetic field changes faster than previously thought
Credit: NASA


Our magnetic field is generated and maintained by a convective flow of molten metal that forms Earth’s outer core. Motion of the liquid iron creates the electric currents that power the field, which not only helps guide navigational systems but also helps shield us from harmful extra terrestrial radiation and hold our atmosphere in place.

The magnetic field is constantly changing. Satellites now provide new means to measure and track its current shifts but the field existed long before the invention of human-made recording devices.

To capture the evolution of the field back through geological time, scientists analyse the magnetic fields recorded by sediments, lava flows and human-made artefacts. Accurately tracking the signal from Earth’s core field is extremely challenging and so the rates of field change estimated by these types of analysis are still debated.

Now, Dr Chris Davies, an Associate Professor from Leeds' School of Earth and Environment, and Professor Catherine Constable, from the Scripps Institution of Oceanography, UC San Diego, in California, have taken a different approach. They combined computer simulations of the field generation process with a recently published reconstruction of time variations in Earth's magnetic field spanning the last 100,000 years.

Their study, published  in Nature Communications, shows that changes in the direction of Earth’s magnetic field reached rates that are up to 10 times larger than the fastest currently reported variations of up to one degree per year.

They demonstrate that these rapid changes are associated with local weakening of the magnetic field. This means these changes have generally occurred around times when the field has reversed polarity or during geomagnetic excursions when the dipole axis — corresponding to field lines that emerge from one magnetic pole and converge at the other — moves far from the locations of the North and South geographic poles.

The clearest example of this in their study is a sharp change in the geomagnetic field direction of roughly 2.5 degrees per year 39,000 years ago. This shift was associated with a locally weak field strength, in a confined spatial region just off the west coast of Central America, and followed the global Laschamp excursion – a short reversal of the Earth’s magnetic field.

Similar events are identified in computer simulations of the field which can reveal many more details of their physical origin than the limited paleomagnetic reconstruction.

Their detailed analysis indicates that the fastest directional changes are associated with movement of reversed flux patches across the surface of the liquid core. These patches are more prevalent at lower latitudes, suggesting that future searches for rapid changes in direction should focus on these areas.

Dr Davies, from the School of Earth and Environment, said: “We have very incomplete knowledge of our magnetic field prior to 400 years ago. Since these rapid changes represent some of the more extreme behaviour of the liquid core they could give important information about the behaviour of Earth’s deep interior.

Professor Constable said: “Understanding whether computer simulations of the magnetic field accurately reflect the physical behaviour of the geomagnetic field as inferred from geological records can be very challenging.

“But in this case we have been able to show excellent agreement in both the rates of change and general location of the most extreme events across a range of computer simulations. Further study of the evolving dynamics in these simulations offers a useful strategy for documenting how such rapid changes occur and whether they are also found during times of stable magnetic polarity like what we are experiencing today.”


The paper Rapid geomagnetic changes inferred from Earth observations and numerical simulations is published in Nature Communications 6 July 2020




Contacts and sources:
Anna Harrison
University of Leeds



Publication: Rapid geomagnetic changes inferred from Earth observations and numerical simulationsChristopher J. Davies, Catherine G. Constable. . Nature Communications, 2020; 11 (1) DOI: 10.1038/s41467-020-16888-0





Owner Behavior Affects Effort and Accuracy in Dogs’ Communications

Communication history and the principle of least effort guide human communications, but the factors guiding dog communications are highly influenced by their owners


Researchers from the Max Planck Institute for the Science of Human History and Friedrich Schiller University in Jena have found that dogs adapt their communicative strategies to their environment and that owner behavior influences communicative effort and success. Experimental results found no evidence that dogs rely on communication history or follow the principle of least effort and suggest that owner behavior has a bigger impact on canine communication than previously thought.


Owners influence how well dogs show where a toy is hidden.

© Theresa Epperlein

Human communication has evolved mechanisms that can be observed across all cultures and languages, including the use of communication history and the principle of least effort. These two factors enable us to use shared information about the past and present and to conserve energy, making communications as effective and efficient as possible. Given the remarkable sensitivity of dogs to human vocalizations, gestures and gazes, researchers have suggested that 30.000 years of domestication and co-evolution with humans may have caused dogs to develop similar principles of communication – a theory known as the domestication hypothesis.

On this basis, researchers designed an experiment that would examine the factors influencing the form, effort and success of dog-human interactions in a hidden-object task. Using 30 dog-owner pairs, researchers focused on a communicative behavior called showing, in which dogs gather the attention of a communicative partner and direct it to an external source.

While the owner waited in another room, an experimenter in view of a participating dog hid the dogs` favourite toy in one of four boxes. When the owner entered the room, the dog had to show its owner where the toy had been hidden. If the owner successfully located the toy, the pair were allowed to play as a reward. Participants were tested in two conditions: a close setup which required more precise showing and a distant setup which allowed for showing in a general direction.
Showing_Milka_Close_gesamteProzedur_kurz from MPI-SHH / Scientific Services on Vimeo.'


The researchers found no evidence to suggest that dogs adhere to the principal of least effort, as they used as much energy in the easier far setup as they did in the more difficult close setup. However, this might have been a result of the owners influence on their dogs’ effort. Secondly, dogs were not affected by different communication histories, as they performed similarly and used similar amounts of energy in both setups regardless of which condition they began with. Despite putting in similar amounts of effort, dogs adapted their showing strategies to be more or less precise, depending on the conditions.

The findings indicate that a crucial factor influencing the effort and accuracy of dogs’ showing is the behaviour of the dog’s owner. Owners who encouraged their dog to show where the toy was hidden increased their dog’s showing effort but generally decreased their showing accuracy.

“We’ve seen in previous studies that if we keep eye contact with the dog or talk in a high-pitched voice, we seem to prompt a ‘ready-to-obey attitude’ which makes dogs very excited to follow our commands. So when owners asked their dogs ‘Is the toy here?’ and pointed at the boxes, they might have caused dogs to just show any box,” says Melanie Henschel, main author of the study.

Although the researchers found no effects of communication history or the principal of least effort, the current study indicates for the first time that owners can influence their dog’s showing accuracy and success.

“We were surprised that encouragement increased mistakes in dogs` showing accuracy. This could have impacts on the training of dogs and handlers in fields where dogs are working professionals. Future studies should focus on the complex effects of the owner’s influence and the best strategies for handlers communicating with a dog,” adds Juliane Bräuer, senior author and head of the DogStudies Lab at MPI-SHH in Jena.



Contacts and sources:
Melanie Henschel
Max Planck Institute for the Science of Human History


Publication: Effect of shared information and owner behavior on showing in dogs (Canis familiaris). Melanie Henschel, James Winters, Thomas F. Müller, Juliane Bräuer. Animal Cognition, 2020; DOI: 10.1007/s10071-020-01409-9




Age-Related Impairments Reversed in Animal Model

Frailty and immune decline are two main features of old age. Researchers from the University of Bern and the University Hospital Bern now demonstrate in an animal model that these two age-related impairments can be halted and even partially reversed using a novel cell-based therapeutic approach.

With age the frequency of adipose tissue eosinophils decreases gradually. This leads to the production of inflammatory mediators, which promote age-related impairments (e.g. frailty and immunosenescence). Eosinophil cell transfers increase the frequency of these cells in adipose tissue and dampen age-related chronic low-grade inflammation. This results in systemic rejuvenation of the aged organism.


Credit:  © DBMR, University of Bern, D. Brigger

Elderly people are more prone to infectious diseases as the function of their immune system continuously declines with progression of age. This becomes especially apparent during seasonal influenza outbreaks or the occurrence of other viral diseases such as COVID-19. As the efficacy of vaccination in the elderly is strongly reduced, this age group is particularly vulnerable to such infectious pathogens and often shows the highest mortality rate. In addition to the age-related immune decline aged individuals are commonly affected by frailty that negatively impacts quality-of-life. Even though the average life-expectancy for humans continuous to rise, living longer is often associated with age-related health issues. 

Important role of belly fat in aging processes identified

Researchers from the Department for BioMedical Reserarch (DBMR) and the Institute of Pathology at the University of Bern as well as the University Hospital Bern (Inselspital) have set out to identify new approaches to improve health-span in a fast-growing aging population. For many years scientists speculated that chronic low-grade inflammation accelerates aging processes and the development of age-related disorders. An international team of researchers under Bernese guidance has now demonstrated that visceral adipose tissue, known as belly fat, crucially contributes to the development of chronic low-grade inflammation. 

Scientist around Dr. Mario Noti, formerly at the Institute of Pathology of the University of Bern and Dr. Alexander Eggel from the Department for BioMedical Research (DBMR) of the Universität of Bern reported that certain immune cells in the belly fat play and an essential role in regulating chronic low-grade inflammation and downstream aging processes. They could show, that these immune cells may be used to reverse such processes. The findings of this study have been published in the scientific journal «Nature Metabolism»and were further highlighted by a News and Views editorial article.

Belly fat as a source of chronic inflammation

The team around Dr. Noti and Dr. Eggel could demonstrated that a certain kind of immune cells, known as eosinophils, which are predominantly found in the blood circulation, are also present in belly fat of both humans and mice. Although classically known to provide protection from parasite infection and to promote allergic airway disease, eosinophils located in belly fat are responsible to maintain local immune homeostasis. With increasing age the frequency of eosinophils in belly fat declines, while the number of pro-inflammatory macrophages increases. Owing to this immune cell dysbalance, belly fat turns into a source of pro-inflammatory mediators accumulating systemically in old age.

Eosinophil cell therapy promotes rejuvenation

In a next step, the researchers investigated the possibility to reverse age-related impairments by restoring the immune cell balance in visceral adipose tissue. "In different experimental approaches, we were able to show that transfers of eosinophils from young mice into aged recipients resolved not only local but also systemic low-grade inflammation", says Dr. Eggel. 

Detection of Eosinophils in human visceral adipose tissue using two different staining methods. Eosinophils are indicated with an arrowhead. AD: adipocytes, V: blood vessel
Nachweis von Eosinophilen in menschlichem Bauchfett mittels zwei unterschiedlicher Färbungen. Die Eosinophile sind mit einer Pfeilspitze markiert. AD: Adipozyten (Fettzelle), V: Blutgefäss.
Credit; . © DBMR, University of Bern, D. Brigger

"In these experiments, we observed that transferred eosinophils were selectively homing into adipose tissue", adds Dr. Noti. This approach had a rejuvenating effect on the aged organism. As a consequence, aged animals showed significant improvements in physical fitness as assessed by endurance and grip strength tests. Moreover, the therapy had a rejuvenating effect on the immune system manifesting in improved vaccination responses of aged mice. 

Translating findings into clinics

"Our results indicate that the biological processes of aging and the associated functional impairments are more plastic than previously assumed", states Dr. Noti. Importantly, the observed age-related changes in adipose immune cell distribution in mice were also confirmed in humans. "A future direction of our research will be to now leverage the gained knowledge for the establishment of targeted therapeutic approaches to promote and sustain healthy aging in humans", says Dr. Eggel.

This study has been supported by the VELUX STIFTUNG, the FONDATION ACTERIA, and funds of the FreeNovation and medical-biological science research programs of Novartis.





Contacts and sources:
Dr. Mario Noti, Dr.  Alexander Eggel
University of Bern

Publication: Eosinophils regulate adipose tissue inflammation and sustain physical and immunological fitness in old age.
Daniel Brigger, Carsten Riether, Robin van Brummelen, Kira I. Mosher, Alicia Shiu, Zhaoqing Ding, Noemi Zbären, Pascal Gasser, Pascal Guntern, Hanadie Yousef, Joseph M. Castellano, Federico Storni, Neill Graff-Radford, Markus Britschgi, Denis Grandgirard, Magdalena Hinterbrandner, Mark Siegrist, Norman Moullan, Willy Hofstetter, Stephen L. Leib, Peter M. Villiger, Johan Auwerx, Saul A. Villeda, Tony Wyss-Coray, Mario Noti, Alexander Eggel. Nature Metabolism, 2020; DOI: 10.1038/s42255-020-0228-3






TESS Mission Discovers Massive Ice Giant, 40X Size of Earth and Just as Dense


The “ice giant” planets Neptune and Uranus are much less dense than rocky, terrestrial planets such as Venus and Earth. Beyond our solar system, many other Neptune-sized planets, orbiting distant stars, appear to be similarly low in density.

Now, a new planet discovered by NASA’s Transiting Exoplanet Survey Satellite, TESS, seems to buck this trend. The planet, named TOI-849 b, is the 749th “TESS Object of Interest” identified to date. Scientists spotted the planet circling a star about 750 light years away every 18 hours, and estimate it is about 3.5 times larger than Earth, making it a Neptune-sized planet. Surprisingly, this far-flung Neptune appears to be 40 times more massive than Earth and just as dense.


NASA’s TESS mission has now found an exoplanet, TOI-849b, that appears to be 40 times more massive than Earth, yet just as dense. This illustration depicts the exoplanet, UCF-1.01. Like TOI-849b, this exoplanet also orbits close to a star and is like “hot Neptune.”
In our solar system, the “ice giants” Neptune and Uranus are far less dense than rocky Venus and Earth. But astrophysicists on NASA’s TESS mission have now found an exoplanet, TOI-849b, that appears to be 40 times more massive than Earth, yet just as dense. This illustration depicts the exoplanet, UCF-1.01. Like TOI-849b, this exoplanet also orbits close to a star and is like “hot Neptune.”
Image credit: NASA/JPL-Caltech

TOI-849 b is the most massive Neptune-sized planet discovered to date, and the first to have a density that is comparable to Earth.

“This new planet is more than twice as massive as our own Neptune, which is really unusual,” says Chelsea Huang, a postdoc in MIT’s Kavli Institute for Astrophysics and Space Research, and a member of the TESS science team. “Imagine if you had a planet with Earth’s average density, built up to 40 times the Earth’s mass. It’s quite crazy to think what’s happening at the center of a planet with that kind of pressure.”

The discovery is reported today in the journal Nature. The study’s authors include Huang and members of the TESS science team at MIT.

A blasted Jupiter?

Since its launch on April 18, 2018, the TESS satellite has been scanning the skies for planets beyond our solar system. The project is one of NASA’s Astrophysics Explorer missions and is led and operated by MIT. TESS is designed to survey almost the entire sky by pivoting its view every month to focus on a different patch of the sky as it orbits the Earth. As it scans the sky, TESS monitors the light from the brightest, nearest stars, and scientists look for periodic dips in starlight that may signal that a planet is crossing in front of a star.

Data taken by TESS, in the form of a star’s light curve, or measurements of brightness, is first made available to the TESS science team, an international, multi-institute group of researchers led by scientists at MIT. These researchers get a first look at the data to identify promising planet candidates, or TESS Objects of Interest. These are shared publicly with the general scientific community along with the TESS data for further analysis.

For the most part, astronomers focus their search for planets on the nearest, brightest stars that TESS has observed. Huang and her team at MIT, however, recently had some extra time to look over data during September and October of 2018, and wondered if anything could be found among the fainter stars. Sure enough, they discovered a significant number of transit-like dips from a star 750 light years away, and soon after, confirmed the existence of TOI-849 b.

“Stars like this usually don’t get looked at carefully by our team, so this discovery was a happy coincidence,” Huang says.

Follow-up observations of the faint star with a number of ground-based telescopes further confirmed the planet and also helped to determine its mass and density.

Huang says that TOI-849 b’s curious proportions are challenging existing theories of planetary formation.

“We’re really puzzled about how this planet formed,” Huang says. “All the current theories don’t fully explain why it’s so massive at its current location. We don’t expect planets to grow to 40 Earth masses and then just stop there. Instead, it should just keep growing, and end up being a gas giant, like a hot Jupiter, at several hundreds of Earth masses.”

One hypothesis scientists have come up with to explain the new planet’s mass and density is that perhaps it was once a much larger gas giant, similar to Jupiter and Saturn — planets with more massive envelopes of gas that enshroud cores thought to be as dense as the Earth.

As the TESS team proposes in the new study, over time, much of the planet’s gassy envelope may have been blasted away by the star’s radiation — not an unlikely scenario, as TOI-849 b orbits extremely close to its host star. Its orbital period is just 0.765 days, or just over 18 hours, which exposes the planet to about 2,000 times the solar radiation that Earth receives from the sun. According to this model, the Neptune-sized planet that TESS discovered may be the remnant core of a much more massive, Jupiter-sized giant.

“If this scenario is true, TOI-849 b is the only remnant planet core, and the largest gas giant core known to exist,” says Huang. “This is something that gets scientists really excited, because previous theories can’t explain this planet.”

This research was funded, in part, by NASA.

Contacts and sources:
Jennifer Chu Massachusetts Institute of Technology (MIT)







Graphene Sensor Simultaneously Tests for the Flu and COVID-19



The novel coronavirus has been compared with the flu almost from the moment it emerged in late 2019. They share a variety of symptoms, and in many cases, an influenza test is part of the process for diagnosing COVID-19.

Researchers at The University of Texas at Austin are now developing a new sensor that can tell the difference between the two illnesses and test for both simultaneously. The development comes as public health experts anticipate a spike in cases during the fall and winter. Knowing whether a patient is sick with the flu or coronavirus is essential because it informs treatment decisions and infection control measures, potentially saving tax dollars and reducing work for medical personnel.

“With a second wave of the coronavirus likely to appear right as we get into flu season, there’s an urgent need for diagnostics that can differentiate between COVID-19 and influenza,” said Deji Akinwande, a professor in the Cockrell School of Engineering’s Department of Electrical and Computer Engineering.

Researchers at the Cockrell School of Engineering are developing a sensor that can test for COVID-19 and the flu simultaneously. 
Credit: University of Texas at Austin.

A dual test improves on current options in several ways, the researchers say. It’s more convenient for patients who wouldn’t have to get multiple tests done. It also saves time for medical personnel when resources are stretched thin. A dual test would also reduce the usage of nasal swabs – since one is needed for each COVID-19 or influenza test – amid a shortage of equipment.

Akinwande and his research team recently received a grant from the National Science Foundation for the work. They have developed a prototype device and are beginning the experimental process.

The sensor is the size of a micro USB drive and is infused with antibodies of both COVID-19 and influenza. One part of the device is sensitive only to the flu, while another part will react only to the coronavirus. The team has not determined yet how the test would be conducted, but it could be done via saliva samples.

“Building a simple sensor for detecting COVID-19 alone wouldn’t be a great advantage for us because there are already several different ways to do so,” said Dmitry Kireev, a postdoctoral fellow in electrical and computer engineering who is working on the project. “The distinction of our work is developing a dual sensor that can quickly differentiate between both diseases.”

The researchers are planning to use inactive samples of COVID-19 and influenza for initial testing of the device, and they will measure how well the sensor connects with the coronavirus’s spike proteins, which help it enter human cells by binding with them.

Lab technician holding swab collection kit,Coronavirus COVID-19 specimen collecting equipment,DNA nasal and oral swabbing for PCR polymerase chain reaction laboratory testing procedure and shipping
Credit: University of Texas - Austin

To develop the sensor, the team is deploying the “wonder material” graphene, constructed into electrolyte gated field-effect transistors as the sensing elements. The atomic thickness of graphene creates extreme sensitivity to anything with a charge, including biomolecules such as viruses, making it ideal as a part of a sensor.

The work builds on a project the team began last year to create graphene-based biosensors. Along with researchers from Nigeria, the team recently submitted a paper for a biosensor to detect iron (ferritin) deficiency in children. In the work, the team combined graphene with anti-ferritin antibodies, making the biosensors reactive to that one biomolecule.

“It became clear that just by changing the antibody, we could pivot the platform to focus on the coronavirus,” Akinwande said.

The team is working with Andy Ellington, a professor in the Department of Molecular Biosciences in the College of Natural Sciences, to integrate the antibodies into the sensors, and Akinwande said he hopes to work with additional collaborators at UT and elsewhere.

If the prototype the team created proves effective in experiments, which will take a couple of months to determine, they will seek to partner with a company to scale up production.



Contacts and sources
:Nat Levy
Cockrell School of Engineering
University of Texas - Austin







Saturday, July 4, 2020

Aerial Undulation’s Role In Flying Snake Glides Revealed



When the paradise tree snake flies from one tall branch to another, its body ripples with waves like green cursive on a blank pad of blue sky. That movement, aerial undulation, happens in each glide made by members of the Chrysopelea family, the only known limbless vertebrates capable of flight. Scientists have known this, but have yet to fully explain it.

For more than 20 years, Jake Socha, a professor in the Department of Biomedical Engineering and Mechanics, has sought to measure and model the biomechanics of snake flight and answer questions about them, like that of aerial undulation’s functional role. For a study published by Nature Physics, Socha assembled an interdisciplinary team to develop the first continuous, anatomically-accurate 3D mathematical model of Chrysopelea paradisi in flight.

The paradise tree snake mid-glide. 
Flying snake glides during experiment
Photo by Jake Socha.

The team, which included Shane Ross, a professor in the Kevin T. Crofton Department of Aerospace and Ocean Engineering, and Isaac Yeaton, a recent mechanical engineering doctoral graduate and the paper’s lead author, developed the 3D model after measuring more than 100 live snake glides. The model factors in frequencies of undulating waves, their direction, forces acting on the body, and mass distribution. With it, the researchers have run virtual experiments to investigate aerial undulation.

In one set of those experiments, to learn why undulation is a part of each glide, they simulated what would happen if it wasn’t — by turning it off. When their virtual flying snake could no longer aerially undulate, its body began to tumble. The test, paired with simulated glides that kept the waves of undulation going, confirmed the team’s hypothesis: aerial undulation enhances rotational stability in flying snakes.

The paradise tree snake is a member of the Chrysopelea family, the only know limbless vertebrates capable of flight.
 Photo by Jake Socha.


Questions of flight and movement fill Socha’s lab. The group has fit their work on flying snakes between studies of how frogs leap from water and skitter across it, how blood flows through insects, and how ducks land on ponds. In part, it was important to Socha to probe undulation’s functional role in snake glides because it would be easy to assume that it didn’t really have one.

“We know that snakes undulate for all kinds of reasons and in all kinds of locomotor contexts,” said Socha. “That’s their basal program. By program, I mean their neural, muscular program⁠ — they’re receiving specific instructions: fire this muscle now, fire that muscle, fire this muscle. It’s ancient. It goes beyond snakes. That pattern of creating undulations is an old one. It’s quite possible that a snake gets into the air, then it goes, 'What do I do? I’m a snake. I undulate.'”

But Socha believed there was much more to it. Throughout the paradise tree snake’s flight, so many things happen at once, it’s difficult to untangle them with the naked eye. Socha described a few steps that take place with each glide ⁠— steps that read as intentional.

First, the snake jumps, usually by curving its body into a “J-loop” and springing up and out. As it launches, the snake reconfigures its shape, its muscles shifting to flatten its body out everywhere but the tail. The body becomes a “morphing wing” that produces lift and drag forces when air flows over it, as it accelerates downward under gravity. Socha has examined these aerodynamic properties in multiple studies. With the flattening comes undulation, as the snake sends waves down its body.

At the outset of the study, Socha had a theory for aerial undulation he explained by comparing two types of aircraft: jumbo jets versus fighter jets. Jumbo jets are designed for stability and start to level back out on their own when perturbed, he said, whereas fighters roll out of control.

So which would the snake be?

“Is it like a big jumbo jet, or is it naturally unstable?” Socha said. “Is this undulation potentially a way of it dealing with stability?”

He believed the snake would be more like a fighter jet.

To run tests investigating undulation’s importance to stability, the team set out to develop a 3D mathematical model that could produce simulated glides. But first, they needed to measure and analyze what real snakes do when gliding.

In 2015, the researchers collected motion capture data from 131 live glides made by paradise tree snakes. They turned The Cube, a four-story black-box theater at the Moss Arts Center, into an indoor glide arena and used its 23 high-speed cameras to capture the snakes’ motion as they jumped from 27 feet up — from an oak tree branch atop a scissor lift — and glided down to an artificial tree below, or onto the surrounding soft foam padding the team set out in sheets to cushion their landings.

The cameras put out infrared light, so the snakes were marked with infrared-reflective tape on 11 to 17 points along their bodies, allowing the motion capture system to detect their changing position over time. Finding the number of measurement points has been key to the study; in past experiments, Socha marked the snake at three points, then five, but those numbers didn’t provide enough information. The data from fewer video points only provided a coarse understanding, making for choppy and low-fidelity undulation in the resulting models.

The team found a sweet spot in 11 to 17 points, which gave high-resolution data. “With this number, we could get a smooth representation of the snake, and an accurate one,” said Socha.

The snakes wore 11 to 17 infrared-reflective markers, which gave the team high-resolution data while still allowing the animals to move freely.
 Photo by Jake Socha.


The researchers went on to build the 3D model by digitizing and reproducing the snake’s motion while folding in measurements they had previously collected on mass distribution and aerodynamics. An expert in dynamic modeling, Ross guided Yeaton’s work on a continuous model by drawing inspiration from work in spacecraft motion.

He had worked with Socha to model flying snakes since 2013, and their previous models treated the snake’s body in parts — first in three parts, as a trunk, a middle, and an end, and then as a bunch of links. “This is the first one that’s continuous,” said Ross. “It’s like a ribbon. It’s the most realistic to this point.”

In virtual experiments, the model showed that aerial undulation not only kept the snake from tipping over during glides, but it increased the horizontal and vertical distances traveled.

Ross sees an analogy for the snake’s undulation in a frisbee’s spin: the reciprocating motion increases rotational stability and results in a better glide. By undulating, he said, the snake is able to balance out the lift and drag forces its flattened body produces, rather than being overwhelmed by them and toppling, and it’s able to go further.


The experiments also revealed to the team details they hadn’t previously been able to visualize. They saw that the snake employed two waves when undulating: a large-amplitude horizontal wave and a newly discovered, smaller-amplitude vertical wave. The waves went side to side and up and down at the same time, and the data showed that the vertical wave went at twice the rate of the horizontal one. “This is really, really freaky,” said Socha. These double waves have only been discovered in one other snake, a sidewinder, but its waves go at the same frequency.


“What really makes this study powerful is that we were able to dramatically advance both our understanding of glide kinematics and our ability to model the system,” said Yeaton. “Snake flight is complicated, and it’s often tricky to get the snakes to cooperate. And there are many intricacies to make the computational model accurate. But it’s satisfying to put all of the pieces together.”

“In all these years, I think I’ve seen close to a thousand glides,” said Socha. “It’s still amazing to see every time. Seeing it in person, there’s something a little different about it. It’s shocking still. What exactly is this animal doing? Being able to answer the questions I’ve had since I was a graduate student, many, many years later, is incredibly satisfying.”

Jzake Socha positions a paradise tree snake on a branch during motion experiments in The Cube at the Moss Arts Center.
 Photo by Michael Diersing.


Socha credits some of the elements that shaped the real and simulated glide experiments to forces out of his control. Chance led him to the indoor glide arena: a few years after the Moss Arts Center opened, Tanner Upthegrove, a media engineer for the Institute for Creativity, Arts, and Technology, or ICAT, asked him if he’d ever thought about working in the Cube.

“What’s the Cube?” he asked. When Upthegrove showed him the space, he was floored. It seemed designed for Socha’s experiments.

In some ways, it was. “Many projects at ICAT used the advanced technology of the Cube, a studio unlike any other in the world, to reveal that which could normally not be seen,” said Ben Knapp, the founding director of ICAT. “Scientists, engineers, artists, and designers join forces here to build, create, and innovate new ways to approach the world’s grandest challenges.”

In one of the center’s featured projects, “Body, Full of Time,” media and visual artists used the space to motion capture the body movements of dancers for an immersive performance. Trading dancers for snakes, Socha was able to make the most of the Cube’s motion capture system. The team could move cameras around, optimizing their position for the snake’s path. They took advantage of latticework at the top of the space to position two cameras pointing down, providing an overhead view of the snake, which they’d never been able to do before.

The Cube is home to a 23-camera motion capture system.
Photo by Jake Socha.


Socha and Ross see potential for their 3D model to continue exploring snake flight. The team is planning outdoor experiments to gather motion data from longer glides. And one day, they hope to cross the boundaries of biological reality.

Right now, their virtual flying snake always glides down, like the real animal. But what if they could get it to move so that it would actually start to go up? To really fly? That ability could potentially be built into the algorithms of robotic snakes, which have exciting applications in search and rescue and disaster monitoring, Ross said.

“Snakes are just so good at moving through complex environments,” said Ross. “If you could add this new modality, it would work not only in a natural setting, but in an urban environment.”


“In some ways, Virginia Tech is a hub for bio-inspired engineering,” said Socha. “Studies like this one not only provide insight into how nature works, but lay the groundwork for design inspired by nature. Evolution is the ultimate creative tinkerer, and we’re excited to continue to discover nature’s solutions to problems like this one, extracting flight from a wiggling cylinder.”





Contacts and sources:
Suzanne Irby
Virginia Tech







Quantum Ffluctuations Can Jiggle Objects on the Human Scale



The universe, as seen through the lens of quantum mechanics, is a noisy, crackling space where particles blink constantly in and out of existence, creating a background of quantum noise whose effects are normally far too subtle to detect in everyday objects.

Now for the first time, a team led by researchers at MIT LIGO Laboratory has measured the effects of quantum fluctuations on objects at the human scale. In a paper published today in Nature, the researchers report observing that quantum fluctuations, tiny as they may be, can nonetheless “kick” an object as large as the 40-kilogram mirrors of the U.S. National Science Foundation’s Laser Interferometer Gravitational-wave Observatory (LIGO), causing them to move by a tiny degree, which the team was able to measure.

MIT physicists have observed that LIGO’s 40-kilogram mirrors can move in response to tiny quantum effects. In this photo, a LIGO optics technician inspects one of LIGO’s mirrors.
MIT physicists have observed that LIGO’s 40-kilogram mirrors can move in response to tiny quantum effects. In this photo, a LIGO optics technician inspects one of LIGO’s mirrors.
Credit: Matt Heintze/Caltech/MIT/LIGO Lab

It turns out the quantum noise in LIGO’s detectors is enough to move the large mirrors by 10-20 meters — a displacement that was predicted by quantum mechanics for an object of this size, but that had never before been measured.

“A hydrogen atom is 10-10 meters, so this displacement of the mirrors is to a hydrogen atom what a hydrogen atom is to us — and we measured that,” says Lee McCuller, a research scientist at MIT’s Kavli Institute for Astrophysics and Space Research.

The researchers used a special instrument that they designed, called a quantum squeezer, to “manipulate the detector’s quantum noise and reduce its kicks to the mirrors, in a way that could ultimately improve LIGO’s sensitivity in detecting gravitational waves,” explains Haocun Yu, a physics graduate student at MIT.

“What’s special about this experiment is we’ve seen quantum effects on something as large as a human,” says Nergis Mavalvala, the Marble Professor and associate head of the physics department at MIT. “We too, every nanosecond of our existence, are being kicked around, buffeted by these quantum fluctuations. It’s just that the jitter of our existence, our thermal energy, is too large for these quantum vacuum fluctuations to affect our motion measurably. With LIGO’s mirrors, we’ve done all this work to isolate them from thermally driven motion and other forces, so that they are now still enough to be kicked around by quantum fluctuations and this spooky popcorn of the universe.”

Yu, Mavalvala, and McCuller are co-authors of the new paper, along with graduate student Maggie Tse and Principal Research Scientist Lisa Barsotti at MIT, along with other members of the LIGO Scientific Collaboration.

A quantum kick

LIGO is designed to detect gravitational waves arriving at the Earth from cataclysmic sources millions to billions of light years away. It comprises twin detectors, one in Hanford, Washington, and the other in Livingston, Louisiana. Each detector is an L-shaped interferometer made up of two 4-kilometer-long tunnels, at the end of which hangs a 40-kilogram mirror.

To detect a gravitational wave, a laser located at the input of the LIGO interferometer sends a beam of light down each tunnel of the detector, where it reflects off the mirror at the far end, to arrive back at its starting point. In the absence of a gravitational wave, the lasers should return at the same exact time. If a gravitational wave passes through, it would briefly disturb the position of the mirrors, and therefore the arrival times of the lasers.

Much has been done to shield the interferometers from external noise, so that the detectors have a better chance of picking out the exceedingly subtle disturbances created by an incoming gravitational wave.

Mavalvala and her colleagues wondered whether LIGO might also be sensitive enough that the instrument might even feel subtler effects, such as quantum fluctuations within the interferometer itself, and specifically, quantum noise generated among the photons in LIGO’s laser.

“This quantum fluctuation in the laser light can cause a radiation pressure that can actually kick an object,” McCuller adds. “The object in our case is a 40-kilogram mirror, which is a billion times heavier than the nanoscale objects that other groups have measured this quantum effect in.”

Noise squeezer

To see whether they could measure the motion of LIGO’s massive mirrors in response to tiny quantum fluctuations, the team used an instrument they recently built as an add-on to the interferometers, which they call a quantum squeezer. With the squeezer, scientists can tune the properties of the quantum noise within LIGO’s interferometer.

The team first measured the total noise within LIGO’s interferometers, including the background quantum noise, as well as “classical” noise, or disturbances generated from normal, everyday vibrations. They then turned the squeezer on and set it to a specific state that altered the properties of quantum noise specifically. They were able to then subtract the classical noise during data analysis, to isolate the purely quantum noise in the interferometer. As the detector constantly monitors the displacement of the mirrors to any incoming noise, the researchers were able to observe that the quantum noise alone was enough to displace the mirrors, by 10-20 meter.

Mavalvala notes that the measurement lines up exactly with what quantum mechanics predicts. “But still it’s remarkable to see it be confirmed in something so big,” she says.

Going a step further, the team wondered whether they could manipulate the quantum squeezer to reduce the quantum noise within the interferometer. The squeezer is designed such that when it set to a particular state, it “squeezes” certain properties of the quantum noise, in this case, phase and amplitude. Phase fluctuations can be thought of as arising from the quantum uncertainty in the light's travel time, while amplitude fluctuations impart quantum kicks to the mirror surface.

“We think of the quantum noise as distributed along different axes, and we try to reduce the noise in some specific aspect,” Yu says.

When the squeezer is set to a certain state, it can for example squeeze, or narrow the uncertainty in phase, while simultaneously distending, or increasing the uncertainty in amplitude. Squeezing the quantum noise at different angles would produce different ratios of phase and amplitude noise within LIGO’s detectors.

The group wondered whether changing the angle of this squeezing would create quantum correlations between LIGO’s lasers and its mirrors, in a way that they could also measure. Testing their idea, the team set the squeezer to 12 different angles and found that, indeed, they could measure correlations between the various distributions of quantum noise in the laser and the motion of the mirrors.

Through these quantum correlations, the team was able to squeeze the quantum noise, and the resulting mirror displacement, down to 70 percent its normal level. This measurement, incidentally, is below what’s called the standard quantum limit, which, in quantum mechanics, states that a given number of photons, or, in LIGO’s case, a certain level of laser power, is expected to generate a certain minimum of quantum fluctuations that would generate a specific “kick” to any object in their path.

By using squeezed light to reduce the quantum noise in the LIGO measurement, the team has made a measurement more precise than the standard quantum limit, reducing that noise in a way that will ultimately help LIGO to detect fainter, more distant sources of gravitational waves.

This research was funded, in part, by the National Science Foundation.




Contacts and sources:
Abby Abazorius
Massachusetts Institute of Technology










NASA’s TESS Delivers New Insights Into an Ultrahot World



Measurements from NASA’s Transiting Exoplanet Survey Satellite (TESS) have enabled astronomers to greatly improve their understanding of the bizarre environment of KELT-9 b, one of the hottest planets known.

“The weirdness factor is high with KELT-9 b,” said John Ahlers, an astronomer at Universities Space Research Association in Columbia, Maryland, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It’s a giant planet in a very close, nearly polar orbit around a rapidly rotating star, and these features complicate our ability to understand the star and its effects on the planet.”

Explore KELT-9 b, one of the hottest planets known. Observations from NASA's Transiting Exoplanet Survey Satellite (TESS) have revealed new details about the planet’s environment. The planet follows a close, polar orbit around a squashed star with different surface temperatures, factors that make peculiar seasons for KELT-9 b.

Credits: NASA's Goddard Space Flight Center

The new findings appear in a paper led by Ahlers published on June 5 in The Astronomical Journal.

Located about 670 light-years away in the constellation Cygnus, KELT-9 b was discovered in 2017 because the planet passed in front of its star for a part of each orbit, an event called a transit. Transits regularly dim the star’s light by a small but detectable amount. The transits of KELT-9 b were first observed by the KELT transit survey, a project that collected observations from two robotic telescopes located in Arizona and South Africa.

Between July 18 and Sept. 11, 2019, as part of the mission’s yearlong campaign to observe the northern sky, TESS observed 27 transits of KELT-9 b, taking measurements every two minutes. These observations allowed the team to model the system’s unusual star and its impact on the planet.

KELT-9 b is a gas giant world about 1.8 times bigger than Jupiter, with 2.9 times its mass. Tidal forces have locked its rotation so the same side always faces its star. The planet swings around its star in just 36 hours on an orbit that carries it almost directly above both of the star’s poles.

KELT-9 b receives 44,000 times more energy from its star than Earth does from the Sun. This makes the planet’s dayside temperature around 7,800 degrees Fahrenheit (4,300 C), hotter than the surfaces of some stars. This intense heating also causes the planet’s atmosphere to stream away into space
.
 This illustration shows how planet KELT-9 b sees its host star. Over the course of a single orbit, the planet twice experiences cycles of heating and cooling caused by the star’s unusual pattern of surface temperatures. Between the star’s hot poles and cool equator, temperatures vary by about 1,500 F (800 C). This produces a “summer” when the planet faces a pole and a “winter” when it faces the cooler midsection. So every 36 hours, KELT-9 b experiences two summers and two winters. 
Illustration of planet KELT-9 b and its host star
Credit: NASA's Goddard Space Flight Center/Chris Smith (USRA)

Its host star is an oddity, too. It’s about twice the size of the Sun and averages about 56 percent hotter. But it spins 38 times faster than the Sun, completing a full rotation in just 16 hours. Its rapid spin distorts the star’s shape, flattening it at the poles and widening its midsection. This causes the star’s poles to heat up and brighten while its equatorial region cools and dims — a phenomenon called gravity darkening. The result is a temperature difference across the star’s surface of almost 1,500 F (800 C).

With each orbit, KELT-9 b twice experiences the full range of stellar temperatures, producing what amounts to a peculiar seasonal sequence. The planet experiences “summer” when it swings over each hot pole and “winter” when it passes over the star’s cooler midsection. So KELT-9 b experiences two summers and two winters every year, with each season about nine hours.

“It’s really intriguing to think about how the star’s temperature gradient impacts the planet,” said Goddard’s Knicole Colón, a co-author of the paper. “The varying levels of energy received from its star likely produce an extremely dynamic atmosphere.”

KELT-9 b's polar orbit around its flattened star produces distinctly lopsided transits. The planet begins its transit near the star's bright poles and then blocks less and less light as it travels over the star's dimmer equator. This asymmetry provides clues to the temperature and brightness changes across the star’s surface, and they permitted the team to reconstruct the star’s out-of-round shape, how it’s oriented in space, its range of surface temperatures, and other factors impacting the planet.

“Of the planetary systems that we've studied via gravity darkening, the effects on KELT-9 b are by far the most spectacular,” said Jason Barnes, a professor of physics at the University of Idaho and a co-author of the paper. “This work goes a long way toward unifying gravity darkening with other techniques that measure planetary alignment, which in the end we hope will tease out secrets about the formation and evolutionary history of planets around high-mass stars.”

TESS is a NASA Astrophysics Explorer mission led and operated by MIT in Cambridge, Massachusetts, and managed by NASA's Goddard Space Flight Center. Additional partners include Northrop Grumman, based in Falls Church, Virginia; NASA’s Ames Research Center in California’s Silicon Valley; the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts; MIT’s Lincoln Laboratory; and the Space Telescope Science Institute in Baltimore. More than a dozen universities, research institutes and observatories worldwide are participants in the mission.

 



Contacts and sources:
By Francis Reddy
NASA’s Goddard Space Flight Center


















Publication:




Core of A Neptune-Sized Planet Revealed for The First Time

The surviving core of a gas giant has been discovered orbiting a distant star by University of Warwick astronomers, offering an unprecedented glimpse into the interior of a planet.

The core, which is the same size as Neptune in our own solar system, is believed to be a gas giant that was either stripped of its gaseous atmosphere or that failed to form one in its early life.

The team from the University of Warwick's Department of Physics reports the discovery today (1 July) in the journal Nature, and is thought to be the first time the exposed core of a planet has been observed.

It offers the unique opportunity to peer inside the interior of a planet and learn about its composition.

Artist's impression showing a Neptune-sized planet in the Neptunian Desert. It is extremely rare to find an object of this size and density so close to its star. 
Credit: University of Warwick/Mark Garlick:

Located around a star much like our own approximately 730 light years away, the core, named TOI 849 b orbits so close to its host star that a year is a mere 18 hours and its surface temperature is around 1800K.

TOI 849 b was found in a survey of stars by NASA's Transiting Exoplanet Survey Satellite (TESS), using the transit method: observing stars for the tell-tale dip in brightness that indicates that a planet has passed in front of them. It was located in the 'Neptunian desert' - a term used by astronomers for a region close to stars where we rarely see planets of Neptune's mass or larger.

The object was then analysed using the HARPS instrument, on a program led by the University of Warwick, at the European Southern Observatory's La Silla Observatory in Chile. This utilises the Doppler effect to measure the mass of exoplanets by measuring their 'wobble' - small movements towards and away from us that register as tiny shifts in the star's spectrum of light.

The team determined that the object's mass is 2-3 times higher than Neptune but it is also incredibly dense, with all the material that makes up that mass squashed into an object the same size.

Lead author Dr David Armstrong from the University of Warwick Department of Physics said: "While this is an unusually massive planet, it's a long way from the most massive we know. But it is the most massive we know for its size, and extremely dense for something the size of Neptune, which tells us this planet has a very unusual history. The fact that it's in a strange location for its mass also helps - we don't see planets with this mass at these short orbital periods.

"TOI 849 b is the most massive terrestrial planet - that has an earth like density - discovered. We would expect a planet this massive to have accreted large quantities of hydrogen and helium when it formed, growing into something similar to Jupiter. The fact that we don't see those gases lets us know this is an exposed planetary core.

"This is the first time that we've discovered an intact exposed core of a gas giant around a star."

There are two theories as to why we are seeing the planet's core, rather than a typical gas giant. The first is that it was once similar to Jupiter but lost nearly all of its outer gas through a variety of methods. These could include tidal disruption, where the planet is ripped apart from orbiting too close to its star, or even a collision with another planet. Large-scale photoevaporation of the atmosphere could also play a role, but can't account for all the gas that has been lost.

Alternatively, it could be a 'failed' gas giant. The scientists believe that once the core of the gas giant formed then something could have gone wrong and it never formed an atmosphere. This could have occurred if there was a gap in the disc of dust that the planet formed from, or if it formed late and the disc ran out of material.

Dr Armstrong adds: "One way or another, TOI 849 b either used to be a gas giant or is a 'failed' gas giant.

"It's a first, telling us that planets like this exist and can be found. We have the opportunity to look at the core of a planet in a way that we can't do in our own solar system. There are still big open questions about the nature of Jupiter's core, for example, so strange and unusual exoplanets like this give us a window into planet formation that we have no other way to explore.

"Although we don't have any information on its chemical composition yet, we can follow it up with other telescopes. Because TOI 849 b is so close to the star, any remaining atmosphere around the planet has to be constantly replenished from the core. So if we can measure that atmosphere then we can get an insight into the composition of the core itself."







Contacts and sources:
Peter Thorley
University of Warwick


Publication: A remnant planetary core in the hot-Neptune desert David J. Armstrong, Théo A. Lopez, […]Zhuchang Zhan Nature volume 583, pages39–42(2020) https://www.nature.com/articles/s41586-020-2421-7 http://dx.doi.org/10.1038/s41586-020-2421-7











The Two ‘Faces’ Of The Earth Uncovered



New Curtin University-led research has uncovered how rocks sourced from the Earth’s mantle are linked to the formation and breakup of supercontinents and super oceans over the past 700 million years, suggesting that the Earth is made up of two distinct ‘faces’.
Credit:  Curtin University

The research, published in the leading Journal Nature Geoscience, examined the chemical and isotopic ‘make-up’ of rocks sourced from thousands of kilometres below the surface to better understand how the Earth’s mantle responds to plate movements that occur near its surface.

Lead author Dr Luc-Serge Doucet, from the Earth Dynamics Research Group in Curtin’s School of Earth and Planetary Sciences, said the Earth’s mantle is currently divided into two main domains, African and Pacific, but little is known about their formation and history and they are commonly assumed to be chemically the same.

“Our team used trace metals such as lead, strontium, and neodymium, from hotspot volcanic islands including the Hawaiian islands in the Pacific Ocean and the La Reunion island in the Indian Ocean, to examine whether these two domains have the same chemical ‘make-up’,” Dr Doucet said.

“We found that the African domain was ‘enriched’ by subducted continental materials, which was linked to the assembly and breakup of the supercontinent Pangaea, whereas no such feature was found in the Pacific domain.”

The team found that the contents of the two mantle domains are not exactly the same as previously thought. Instead, the Earth appears to have two chemically distinct hemispheric ‘faces’, with the Pacific ring of fire being the surface expression of the boundary between the two.

Co-author John Curtin Distinguished Professor Zheng Xiang Li, head of the Earth Dynamics Research Group, said the two chemically distinct hemispheres discovered by the team can best be explained by the distinct evolutionary histories of the two mantle domains during the Rodinia to Pangaea supercontinent cycles.

“We found that the African mantle domain contains continental materials, which were brought down by the subduction system for at least the past 600 million years. However, the Pacific mantle domain has been protected from the infiltration of such materials,” Professor Li said.

“Our research findings are significant as they showcase a dynamic relationship between plate tectonic processes that operate near the surface and the formation and evolution of Earth’s deep mantle structures.

“The work helps us to understand what drives plate tectonics and the formation and reservation of global geotectonic features such as the Pacific ring of fire. The dynamic and interactive nature of the entire Earth system has important implications on the formation of Earth resources, the evolution of Earth environment, and even the evolution of life.”

The research was co-authored by researchers from Curtin’s School of Earth and Planetary Sciences, Tanta University in Egypt, St Francis Xavier University in Canada, Université Libre de Bruxelles in Belgium, Queen’s University in Canada, and the Chinese Academy of Sciences in Beijing.

The full paper titled, ‘Distinct formation history for deep mantle domains reflected in geochemical differences ’, and can be found online here.



Contacts and sources:
Lauren SydorukCurtin University