Hubble snaps close-up of celebrity comet NEOWISE

 NASA Hubble Space Telescope images of comet NEOWISE, taken on Aug. 8, zero in on the visitor's coma, the gossamer shell of gas and dust that surrounds its nucleus as it is heated by the Sun. This is the first time Hubble has photographed a comet of this brightness at such resolution after this close of a pass by the Sun.

The comet photos were taken after NEOWISE skimmed closest to the Sun on July 3, 2020, at a distance of 27 million miles (43 million kilometers). Other comets often break apart due to thermal and gravitational stresses at such close encounters, but Hubble's view shows that apparently NEOWISE's solid nucleus stayed intact.

"Hubble has far better resolution than we can get with any other telescope of this comet," said lead researcher Qicheng Zhang of Caltech in Pasadena, California. "That resolution is very key for seeing details very close to the nucleus. It lets us see changes in the dust right after it's stripped from that nucleus due to solar heat, sampling dust as close to the original properties of the comet as possible."

The heart of the comet, its icy nucleus, is too small to be seen by Hubble. The ball of ice may be no more than 3 miles (4.8 kilometers) across. Instead, the Hubble image captures a portion of the vast cloud of gas and dust enveloping the nucleus, which measures about 11,000 miles (18,000 kilometers) across in this photo. Hubble resolves a pair of jets from the nucleus shooting out in opposite directions. They emerge from the nucleus as cones of dust and gas, and then are curved into broader fan-like structures by the rotation of the nucleus. Jets are the result of ice sublimating beneath the surface with the resulting dust/gas being squeezed out at high velocity.

The Hubble photos may help reveal the color of the comet's dust and how those colors change as the comet moves away from the Sun. This, in turn, may explain how solar heat affects the composition and structure of that dust in the comet's coma. The ultimate goal here would be to learn the original properties of the dust to learn more about the conditions of the early solar system in which it formed.

Comet NEOWISE is considered the brightest comet visible from the Northern Hemisphere since 1997's Hale-Bopp. It's headed beyond the outer solar system, now traveling at a whopping 144,000 miles per hour. It will not return to the Sun for another nearly 7,000 years.

Researchers are currently delving more into the data to see what they're able to confirm.

NASA's Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) mission first discovered its namesake comet in March 2020. As the comet made its way closer to the Sun, searing heat melted its ices, unleashing dust and gas that leaves the signature tails. Throughout the summer, ground-based sky watchers in the Northern Hemisphere were able to catch a view of the traveler moving across the sky.

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Genomic analysis reveals many animal species may be vulnerable to SARS-CoV-2 infection

 Humans are not the only species facing a potential threat from SARS-CoV-2, the novel coronavirus that causes COVID-19, according to a new study from the University of California, Davis.

An international team of scientists used genomic analysis to compare the main cellular receptor for the virus in humans -- angiotensin converting enzyme-2, or ACE2 -- in 410 different species of vertebrates, including birds, fish, amphibians, reptiles and mammals.

ACE2 is normally found on many different types of cells and tissues, including epithelial cells in the nose, mouth and lungs. In humans, 25 amino acids of the ACE2 protein are important for the virus to bind and gain entry into cells.

The researchers used these 25 amino acid sequences of the ACE2 protein, and modeling of its predicted protein structure together with the SARS-CoV-2 spike protein, to evaluate how many of these amino acids are found in the ACE2 protein of the different species.

"Animals with all 25 amino acid residues matching the human protein are predicted to be at the highest risk for contracting SARS-CoV-2 via ACE2," said Joana Damas, first author for the paper and a postdoctoral research associate at UC Davis. "The risk is predicted to decrease the more the species' ACE2 binding residues differ from humans."

About 40 percent of the species potentially susceptible to SARS-CoV-2 are classified as "threatened" by the International Union for Conservation of Nature and may be especially vulnerable to human-to-animal transmission. The study was published Aug. 21 in the Proceedings of the National Academy of Sciences.

"The data provide an important starting point for identifying vulnerable and threatened animal populations at risk of SARS-CoV-2 infection," said Harris Lewin, lead author for the study and a distinguished professor of evolution and ecology at UC Davis. "We hope it inspires practices that protect both animal and human health during the pandemic."

Endangered species predicted to be at risk

Several critically endangered primate species, such as the Western lowland gorilla, Sumatran orangutan and Northern white-cheeked gibbon, are predicted to be at very high risk of infection by SARS-CoV-2 via their ACE2 receptor.

Other animals flagged as high risk include marine mammals such as gray whales and bottlenose dolphins, as well as Chinese hamsters.

Domestic animals such as cats, cattle and sheep were found to have a medium risk, and dogs, horses and pigs were found to have low risk for ACE2 binding. How this relates to infection and disease risk needs to be determined by future studies, but for those species that have known infectivity data, the correlation is high.

In documented cases of SARS-COV-2 infection in mink, cats, dogs, hamsters, lions and tigers, the virus may be using ACE2 receptors or they may use receptors other than ACE2 to gain access to host cells. Lower propensity for binding could translate to lower propensity for infection, or lower ability for the infection to spread in an animal or between animals once established.

Because of the potential for animals to contract the novel coronavirus from humans, and vice versa, institutions including the National Zoo and the San Diego Zoo, which both contributed genomic material to the study, have strengthened programs to protect both animals and humans.

"Zoonotic diseases and how to prevent human to animal transmission is not a new challenge to zoos and animal care professionals," said co-author Klaus-Peter Koepfli, senior research scientist at Smithsonian-Mason School of Conservation and former conservation biologist with the Smithsonian Conservation Biology Institute's Center for Species Survival and Center for Conservation Genomics. "This new information allows us to focus our efforts and plan accordingly to keep animals and humans safe."

The authors urge caution against overinterpreting the predicted animal risks based on the computational results, noting the actual risks can only be confirmed with additional experimental data. The list of animals can be found here.

Research has shown that the immediate ancestor of SARS-CoV-2 likely originated in a species of bat. Bats were found to be at very low risk of contracting the novel coronavirus via their ACE2 receptor, which is consistent with actual experimental data.

Whether bats directly transmitted the novel coronavirus directly to humans, or whether it went through an intermediate host, is not yet known, but the study supports the idea that one or more intermediate hosts was involved. The data allow researchers to zero in on which species might have served as an intermediate host in the wild, assisting efforts to control a future outbreak of SARS-CoV-2 infection in human and animal populations.

Additional authors on the study include: Marco Corbo, UC Davis Genome Center; Graham M. Hughes and Emma C. Teeling, University College Dublin, Ireland; Kathleen C. Keough and Katherine S. Pollard, UC San Francisco; Corrie A. Painter, Nicole S. Persky, Diane P. Genereux, Ross Swofford, Kerstin Lindblad-Toh and Elinor K. Karlsson, Broad Institute of MIT and Harvard, Cambridge, Massachussetts; Michael Hiller, Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany; Andreas R. Pfenning, Carnegie Mellon University, Pittsburgh; Huabin Zhao, Wuhan University, Wuhan, China; Oliver A. Ryder, San Diego Zoo Institute for Conservation Research, Escondido, and UC San Diego; Martin T. Nweeia, Harvard School of Dental Medicine, Boston, and Smithsonian Institution, Washington D.C.

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Cliff collapse reveals 313-million-year-old fossil footprints in Grand Canyon National Park

 Paleontological research has confirmed a series of recently discovered fossils tracks are the oldest recorded tracks of their kind to date within Grand Canyon National Park. In 2016, Norwegian geology professor, Allan Krill, was hiking with his students when he made a surprising discovery. Lying next to the trail, in plain view of the many hikers, was a boulder containing conspicuous fossil footprints. Krill was intrigued, and he sent a photo to his colleague, Stephen Rowland, a paleontologist at the University of Nevada Las Vegas.

The trailside tracks have turned out to be even more significant than Krill first imagined. "These are by far the oldest vertebrate tracks in Grand Canyon, which is known for its abundant fossil tracks" says Rowland. "More significantly," he added, "they are among the oldest tracks on Earth of shelled-egg-laying animals, such as reptiles, and the earliest evidence of vertebrate animals walking in sand dunes."

The track-bearing boulder fell from a nearby cliff-exposure of the Manakacha Formation. The presence of a detailed geologic map of the strata along the Bright Angel Trail, together with previous studies of the age of the Manakacha Formation, allowed the researchers to pin down the age of the tracks quite precisely to 313 +/- 0. 5 million years.

The newly discovered tracks record the passage of two separate animals on the slope of a sand dune. Of interest to the research team is the distinct arrangement of footprints. The researchers' reconstruction of this animal's footfall sequence reveals a distinctive gait called a lateral-sequence walk, in which the legs on one side of the animal move in succession, the rear leg followed by the foreleg, alternating with the movement of the two legs on the opposite side. "Living species of tetrapods―dogs and cats, for example―routinely use a lateral-sequence gait when they walk slowly," says Rowland. "The Bright Angel Trail tracks document the use of this gait very early in the history of vertebrate animals. We previously had no information about that." Also revealed by the trackways is the earliest-known utilization of sand dunes by vertebrate animals.

From Science Daily

Spinning black hole powers jet by magnetic flux

 Black holes are at the center of almost all galaxies that have been studied so far. They have an unimaginably large mass and therefore attract matter, gas and even light. But they can also emit matter in the form of plasma jets -- a kind of plasma beam that is ejected from the centre of the galaxy with tremendous energy. A plasma jet can extend several hundred thousand light years far into space.

When this intense radiation is emitted, the black hole remains hidden because the light rays near it are strongly bent leading to the appearance of a shadow. This was recently reported by researchers of the Event Horizon Telescope (EHT) collaboration for the massive black hole in the giant ellipse galaxy M87.

In quasar 3C279 -- also a black hole -- the EHT team found another phenomenon: At a distance of more than a thousand times the shadow of the black hole, the core of a plasma jet suddenly lit up. How the energy for this jet could get there as if through an invisible chimney was not yet known.

Extremely flickering gamma radiation detected

This quasar has now been observed with the NASA space telescope Fermi-LAT by the astrophysicist Amit Shukla, who until 2018 did research at Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany. He now is working at the Indian Institute of Technology in Indore. Shukla discovered that the core of the jet, which was found in the millimeter wavelength range, also emits high-energy gamma radiation, but with an extremely flickering brightness. This brightness can double within a few minutes, as reported in the journal Nature Communications.

The special pattern of the sequence of brightness changes is characteristic of a universal process called magnetic reconnection, which occurs in many astrophysical objects with strong magnetic fields. Solar activity also has to do with the dynamics of magnetic fields and reconnection. This was recently demonstrated by observing "campfires" in the solar atmosphere with the "Solar Orbiter" mission of the European Space Agency ESA.

Invisibly stored energy is suddenly released

But back to the quasar 3C279: "I saw how the analysis of the data revealed the special pattern of magnetic reconnection in the light curve. It felt as if I had suddenly deciphered a hieroglyph in the black hole alphabet," says Amit Shukla happily.

During reconnection, energy that is initially stored invisibly in the magnetic field is suddenly released in numerous "mini-jets." In these jets, particles are accelerated, which then produce the observed gamma radiation. Magnetic reconnection would explain how the energy reaches the jet's core from the black hole and where it ultimately comes from.

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Unveiling rogue planets with NASA's Roman Space Telescope

 New simulations show that NASA's Nancy Grace Roman Space Telescope will be able to reveal myriad rogue planets -- freely floating bodies that drift through our galaxy untethered to a star. Studying these island worlds will help us understand more about how planetary systems form, evolve, and break apart.

Astronomers discovered planets beyond our solar system, known as exoplanets, in the 1990s. We quickly went from knowing of only our own planetary system to realizing that planets likely outnumber the hundreds of billions of stars in our galaxy. Now, a team of scientists is finding ways to improve our understanding of planet demographics by searching for rogue worlds.

"As our view of the universe has expanded, we've realized that our solar system may be unusual," said Samson Johnson, a graduate student at Ohio State University in Columbus who led the research effort. "Roman will help us learn more about how we fit in the cosmic scheme of things by studying rogue planets."

The findings, published in the Astronomical Journal, center on the Roman Space Telescope's ability to locate and characterize isolated planets. Astronomers have only tentatively discovered a few of these nomad worlds so far because they are so difficult to detect.

Finding galactic nomads

Roman will find rogue planets by conducting a large microlensing survey. Gravitational lensing is an observational effect that occurs because the presence of mass warps the fabric of space-time. The effect is extreme around very massive objects, like black holes and entire galaxies. Even solitary planets cause a detectable degree of warping, called microlensing.

If a rogue planet aligns closely with a more distant star from our vantage point, the star's light will bend as it travels through the curved space-time around the planet. The result is that the planet acts like a natural magnifying glass, amplifying light from the background star. Astronomers see the effect as a spike in the star's brightness as the star and planet come into alignment. Measuring how the spike changes over time reveals clues to the rogue planet's mass.

"The microlensing signal from a rogue planet only lasts between a few hours and a couple of days and then is gone forever," said co-author Matthew Penny, an assistant professor of physics and astronomy at Louisiana State University in Baton Rouge. "This makes them difficult to observe from Earth, even with multiple telescopes. Roman is a game-changer for rogue planet searches."

Microlensing offers the best way to systematically search for rogue planets -- especially those with low masses. They don't shine like stars and are often very cool objects, emitting too little heat for infrared telescopes to see. These vagabond worlds are essentially invisible, but Roman will discover them indirectly thanks to their gravitational effects on the light of more distant stars.

Lessons from cosmic castaways

Johnson and co-authors showed that Roman will be able to detect rogue planets with masses as small as Mars. Studying these planets will help narrow down competing models of planetary formation.

The planet-building process can be chaotic, since smaller objects collide with one another and sometimes stick together to form larger bodies. It's similar to using a piece of playdough to pick up other pieces. But occasionally collisions and close encounters can be so violent that they fling a planet out of the gravitational grip of its parent star. Unless it manages to drag a moon along with it, the newly orphaned world is doomed to wander the galaxy alone.

Rogue planets may also form in isolation from clouds of gas and dust, similar to how stars grow. A small cloud of gas and dust could collapse to form a central planet instead of a star, with moons instead of planets surrounding it.

Roman will test planetary formation and evolution models that predict different numbers of these isolated worlds. Determining the abundance and masses of rogue planets will offer insight into the physics that drives their formation. The research team found that the mission will provide a rogue planet count that is at least 10 times more precise than current estimates, which range from tens of billions to trillions in our galaxy. These estimates mainly come from observations by ground-based telescopes.

Since Roman will observe above the atmosphere, nearly a million miles away from Earth in the direction opposite the Sun, it will yield far superior microlensing results. In addition to providing a sharper view, Roman's perspective will allow it to stare at the same patch of sky continuously for months at a time. Johnson and his colleagues showed that Roman's microlensing survey will detect hundreds of rogue planets, even though it will search only a relatively narrow strip of the galaxy.

Part of the study involved determining how to analyze the mission's future data to obtain a more accurate census. Scientists will be able to extrapolate from Roman's rogue planet count to estimate how common these objects are throughout the entire galaxy.

"The universe could be teeming with rogue planets and we wouldn't even know it," said Scott Gaudi, a professor of astronomy at Ohio State University and a co-author of the paper. "We would never find out without undertaking a thorough, space-based microlensing survey like Roman is going to do."

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When learning on your own is not enough

 It is no secret that people underlie social influences. For example, at the lunch counter of a new company, when we are unsure which dish would taste good, we monitor other peoples' choices to obtain some guidance for our own menu selection. This phenomenon, which is referred to as social influence, was demonstrated experimentally starting in the 1950s by social psychologist Solomon Asch.

In the new study, researchers from the University Medical Center Hamburg-Eppendorf (UKE) in Germany placed groups of five volunteers in the same computer-based decision-making experiment, where each of them was presented with two abstract symbols. Their objective was to find out which symbol would lead to more monetary rewards in the long run. In each round of the experiment, every person first made a choice between the two symbols, and then they observed which symbols the other four people had selected; next, every person could decide to stick with their initial choice or switch to the alternative symbol. Finally, a monetary outcome, either a win or a loss, was delivered to every one according to their second decision. "This way, we enable real-time interactions among the volunteers, which greatly enhances ecological validity, " says study leader Lei Zhang, then at the UKE and now a postdoctoral researcher at the University of Vienna.

In fact, which symbol was related to more reward was always changing. At the beginning of the experiment, one of the two symbols returned monetary rewards in 70% of the time, and after a few rounds, it provided rewards in only 30% of the time. These changes took place multiple times throughout the experiment. "This so-called reversal learning paradigm will create uncertainty for volunteers so that they will always need to learn and relearn to gain more outcomes. In particular, when the reversal just happened, some people in the group may pick it faster than the others, and if so, the others could combine this social information into their own decision-making processes, " explains Jan Gläscher, who leads a research group on valuation and social decision-making at the UKE.

Expectedly, the volunteers switched more often when they were confronted with opposing choices from the others, but interestingly, the second choice (after considering social information) reflected the reward structure better than the first choice. How to explain this finding? The researchers used sophisticated models to quantify volunteers' behavior, and they unveiled separate computational strategies for direct learning and social learning. "At the beginning of each round, the volunteers were combining their own direct learning experience and social learning experience to guide their choice," Zhang says, "whereby direct learning follows a simple reinforcement learning algorithm, and social learning is instantiated by tracking the others' reward history."

Within each group, the researchers scanned one of the volunteers' brain using functional magnetic resonance imaging, which allowed them to measure when and where the brain carries out both direct learning and social learning, and to characterize whether the two types of learning actually are associated with different neural signatures. The brain scans showed that direct learning is represented in the area called the ventromedial prefrontal cortex, whereas social learning is represented in the area called the anterior cingulate cortex. These two areas also interact with an area in the middle of the brain called the striatum, "which computes both reward prediction error and social prediction error, quantifying trial-and-error learning to inform behavior" says Gläscher. "These indicate an integrated brain network supporting social influence in human decision-making."

These findings suggest that two unique types of learning signals are computed in distinct but interacting regions in the human brain, and represent separate computational strategies for decision-making in social contexts. "Direct learning is efficient in stable situations," explains Gläscher, "and when situations are changing and uncertain, social learning may play an important role together with direct learning to adapt to novel situations, such as deciding on the lunch menu at a new company."

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The most sensitive instrument in the search for life beyond Earth

 The question of whether life exists beyond the Earth is one of humanity's most fundamental questions. Future NASA missions, for example, aim to examine the ice moons of Jupiter and Saturn, which may potentially shelter life in the liquid oceans underneath the thick layer of ice, on the ground. Proving traces of life beyond the Earth is extremely challenging, however. Highly sensitive instruments which take measurements on the ground with the greatest possible degree of autonomy and with high precision -- millions of kilometers from the Earth and thus without direct support from humankind -- are required.

An international group of researchers under the leadership of Andreas Riedo and Niels Ligterink at the University of Bern have now developed ORIGIN, a mass spectrometer which can detect and identify the smallest amounts of such traces of life. They describe the instrument in a recently published article in the specialist journal Nature Scientific Reports. Niels Ligterink from the Center for Space and Habitability (CSH) is the lead author of the international study, and co-author Andreas Riedo from the Physics Institute at the University of Bern developed the instrument in the laboratories of the space research and planetary sciences divison of the Physics Institute. Various international space agencies, particularly NASA, have already expressed interest in testing ORIGIN for future missions.

New instrument required

Since the first Mars mission "Viking" in the 1970s, humanity has been searching for traces of life on Mars using highly specialized instruments which are installed on landing platforms and rovers. In its early years, Mars was Earth-like, had a dense atmosphere and even liquid water. However, as Niels Ligterink explains, Mars lost its protective atmosphere over the course of time: "As a result of this, the surface of Mars is subjected to high solar and cosmic radiation which makes life on the surface impossible." NASA's "Curiosity" rover is currently examining Mars in detail but with no concrete indications of traces of life to date.

Since the discovery by the Cassini and Galileo missions of the global oceans beneath kilometers of ice layers on Jupiter's moon Europa and Saturn's moon Enceladus, these two bodies have increasingly become the focus of the search for extraterrestrial life for researchers. According to current knowledge, the oceans have all of the properties which are not only needed for the occurrence of life, but also which provide environments in which life can exist in the long term. NASA therefore plans to land a mission on Jupiter's moon Europa around 2030 and take measurements on the ground. The goal: Identification of life. Co-author Prof. Dr. Peter Wurz from the Physics Institute at the University of Bern says: "Concepts which were specially developed for Mars cannot be simply applied to other bodies in our solar systembecause they are very different. New instruments with higher sensitivity and simpler and more robust analysis systems must be designed and used."

Unprecedented measurement sensitivity for proof of life in space

ORIGIN is one such new instrument which outperforms previous space instruments many terms over in terms of its measurement sensitivty. Various international space agencies have expressed great interest in the instrument for future missions. Andreas Riedo says: "NASA has invited us to particpaite and test our instrument in the Arctic. The Artic is the optimal test environment in the context of the EUROPA LANDER mission, which should start in 2025, which will allow us to demonstrate the performance of ORIGIN."

Amino acids are key components of life as we know it on Earth. Contemporaneous proof of certain amino acids on extraterrestrial surfaces, such as those of Europa, allow conclusions to be drawn about possible life. The measurement principle developed by the Bern-based researchers is simple. Niels Ligterink explains: "Laser pulses are directed at the surface to be examined. In the process, small amounts of material are detached, the chemical composition of which is analyzed by ORIGIN in a second step." Andreas Riedo adds: "The compelling aspect of our technology is that no complicated sample preparation techniques, which could potentially affect the result, are required. This was one of the biggest problems on Mars until now," says Riedo. The amino acids which have been analyzed with ORIGIN to date have a specific chemical fingerprint which allows them to be directly identified. Niels Ligterink: "To be honest, we didn't expect that our first measurements would already be able to identify amino acids."

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A quantum thermometer to measure the coldest temperatures in the universe

 Physicists from Trinity College Dublin have proposed a thermometer based on quantum entanglement that can accurately measure temperatures a billion times colder than those in outer space.

These ultra-cold temperatures arise in clouds of atoms, known as Fermi gases, which are created by scientists to study how matter behaves in extreme quantum states.

The work was led by the QuSys team at Trinity with postdoctoral fellows, Dr Mark Mitchison, Dr Giacomo Guarnieri and Professor John Goold, in collaboration with Professor Steve Campbell (UCD) and Dr Thomas Fogarty and Professor Thomas Busch working at OIST, Okinawa, Japan.

Discussing the proposal, Professor Goold, head of Trinity's QuSys group, explains what an ultra-cold gas is. He said:

"The standard way in which a physicist thinks about a gas is to use a theory known as statistical mechanics. This theory was invented by giants of physics such as Maxwell and Boltzmann in the 19th century. These guys revived an old idea from the Greek philosophers that macroscopic phenomena, such as pressure and temperature, could be understood in terms of the microscopic motion of atoms. We need to remember that at the time, the idea that matter was made of atoms was revolutionary."

"At the dawn of the 20th century, another theory came to fruition. This is quantum mechanics and it may be the most important and accurate theory we have in physics. A famous prediction of quantum mechanics is that single atoms acquire wave-like features, which means that below a critical temperature they can combine with other atoms into a single macroscopic wave with exotic properties. This prediction led to a century-long experimental quest to reach the critical temperature. Success was finally achieved in the 90s with the creation of the first ultra-cold gases, cooled with lasers (Nobel Prize 1997) and trapped with strong magnetic fields -- a feat which won the Nobel Prize in 2001."

"Ultra-cold gases like these are now routinely created in labs worldwide and they have many uses, ranging from testing fundamental physics theories to detecting gravitational waves. But their temperatures are mind-bogglingly low at nanokelvin and below! Just to give you an idea, one kelvin is -271.15 degrees Celsius. These gases are a billion times colder than that -- the coldest places in the universe and they are created right here on Earth."

So what exactly is a Fermi gas?

"All particles in the universe, including atoms, come in one of two types called 'bosons' and 'fermions'. A Fermi gas comprises fermions, named after the physicist Enrico Fermi. At very low temperatures, bosons and fermions behave completely differently. While bosons like to clump together, fermions do the opposite. They are the ultimate social distancers! This property actually makes their temperature tricky to measure."

Dr Mark Mitchison, the first author of the paper, explains:

"Traditionally, the temperature of an ultra-cold gas is inferred from its density: at lower temperatures the atoms do not have enough energy to spread far apart, making the gas denser. But fermions always keep far apart, even at ultra-low temperatures, so at some point the density of a Fermi gas tells you nothing about temperature."

"Instead, we proposed using a different kind of atom as a probe. Let's say that you have an ultra-cold gas made of lithium atoms. You now take a different atom, say potassium, and dunk it into the gas. Collisions with the surrounding atoms change the state of your potassium probe and this allows you to infer temperature. Technically speaking, our proposal involves creating a quantum superposition: a weird state where the probe atom simultaneously does and doesn't interact with the gas. We showed that this superposition changes over time in a way that is very sensitive to temperature."

Dr Giacomo Guarnieri gives the following analogy:

"A thermometer is just a system whose physical properties change with temperature in a predictable way. For example, you can take the temperature of your body by measuring the expansion of mercury in a glass tube. Our thermometer works in an analogous way, but instead of mercury we measure the state of single atoms that are entangled (or correlated) with a quantum gas."

Professor Steve Campbell, UCD, remarks:

"This isn't just a far-flung idea -- what we are proposing here can actually be implemented using technology available in modern atomic physics labs. That such fundamental physics can be tested is really amazing. Among the various emerging quantum technologies, quantum sensors like our thermometer are likely to make the most immediate impact, so it is a timely work and it was highlighted by the editors of Physical Review Letters for that reason."

Professor Goold adds:

"In fact one of the reasons that this paper was highlighted was precisely because we performed calculations and numerical simulations with a particular focus on an experiment that was performed in Austria and published a few years ago in Science. Here the Fermi gas is a dilute gas of trapped Lithium atoms which were in contact with Potassium impurities. The experimentalists are able to control the quantum state with radio frequency pulses and measure out information on the gas. These are operations that are routinely used in other quantum technologies."

"The timescales that are accessible are simply amazing and would be unprecedented in traditional condensed matter physics experiments. We are excited that our idea to use these impurities as a quantum thermometer with exquisite precision could be implemented and tested with existing technology."

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Defiance and low trust in medical doctors related to vaccine scepticism

 The results of a study conducted by scientists at the University of Turku, Åbo Akademi University, and University of Bristol, show that people who tend to react negatively to rules and recommendations have lower trust in medical doctors and a more negative attitude towards vaccines, or reject vaccines for themselves or their children.

"The vaccine recommendations given by authorities or the social pressure in society to get vaccinated may cause defiance in people who tend to react negatively when they feel that they are forced to do something or that someone is trying to persuade them," says Anna Soveri, Academy Research Fellow at the University of Turku, Finland.

Because of the defiance, people may act contrary to what is expected of them.

"In this case, defiance can lead to scepticism towards medical doctors and negative attitudes towards vaccines, or even vaccine refusal," says Soveri.

Use of Alternative Medicine Quite Common

The study also showed that defiance and low trust in doctors are related to a higher likelihood to use complementary and alternative medicine (CAM). CAM refers to treatments and substances that are not included in evidence-based medicine, meaning treatments and substances for which the efficacy has not been clearly demonstrated through established scientific methods.

In the study, 770 parents of young children were presented with a list of CAM products, from which they were asked to select the ones they had used during the past 12 months to treat an illness or to maintain good health. Almost 40 per cent of the parents reported using one or more CAM products.

"To use complementary and alternative medicine may be a way for people to feel like they are free to make decisions in matters that concern their own health," says Soveri.

High Trust towards Doctors

Half of the parents reported that they had taken the flu vaccine during the preceding season. Approximately 75 per cent of the parents had accepted the childhood vaccines for their children without hesitation, but approximately seven per cent had refused to take a vaccine for their child at least once.

However, most parents expressed high or relatively high trust in doctors.

"For example, nine out of ten parents partly or completely trusted the doctors' ability to make correct diagnoses and that doctors have their patients' best interest in mind when making health-related decisions," tells Soveri.

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A healthy lifestyle for cardiovascular health also promotes good eye health

 In a new study, investigators found that ideal cardiovascular health, which is indicative of a healthy lifestyle, was associated with lower odds for ocular diseases especially diabetic retinopathy. These findings appearing in the American Journal of Medicine, published by Elsevier, suggest that interventions to prevent cardiovascular diseases may also hold promise in preventing ocular diseases.

Globally, about 2.2 billion people suffer from ocular diseases leading to vision impairment or blindness. Approximately half of these cases could have been prevented. The leading causes of vision impairment or blindness are age-related macular degeneration, diabetic retinopathy, cataract, and glaucoma.

"Earlier studies have observed associations between eye diseases and individual lifestyle factors such as smoking, obesity, or hypertension," explained lead investigator Duke Appiah, PhD, MPH, Department of Public Health, Texas Tech University Health Sciences Center, Lubbock, TX, USA. "It is known that these metrics of ideal cardiovascular health do not work alone and may interact additively to result in diseases. However, prior to our research, no other studies have comprehensively evaluated the association of all of the metrics of ideal cardiovascular health with ocular diseases."

Most ocular diseases show few symptoms at early stages and many people may not seek medical care despite readily available treatments. A recent online nationwide survey consisting of all racial and ethnic groups in the United States conducted by the Wilmer Eye Institute at Johns Hopkins University School of Medicine showed that 88 percent of the 2,044 respondents considered good vision to be vital to overall health with 47 percent of them rating losing their vision as the worst disease that could ever happen to them. Alarmingly, 25 percent did not have any knowledge about ocular diseases and their risk factors.

This research shows that following healthy lifestyle and behavior habits can all contribute to good cardiovascular health as assessed by adherence to the American Heart Association's prescription for health metric known as Life's Simple Seven (LS7). LS7 is based on the status of seven cardiovascular disease risk factors: not smoking, regular physical activity, healthy diet, maintaining normal weight, and controlling cholesterol, blood pressure, and blood glucose levels.

Practicing these healthy lifestyles together was found to be associated with lower odds for age-related macular degeneration, diabetic retinopathy, cataract, and glaucoma. Individuals with optimal cardiovascular health had 97 percent lower odds for diabetic retinopathy compared to individuals with inadequate cardiovascular health.

Investigators evaluated data from 6,118 adults aged 40 or more years old who took part in the 2005-2008 National Health and Nutrition Examination Survey. The average age of participants was 57 years old, 53 percent of whom were women. A one unit increase in LS7 scores was associated with reduced odds for age-related macular degeneration, diabetic retinopathy, and glaucoma.

"Overall, we believe that primary prevention and early detection approaches of ocular diseases are important, considering that over half of all deaths from ocular diseases and cardiovascular diseases are known to be preventable," commented co-investigators Noah De La Cruz, MPH, and Obadeh Shabaneh, MPH, both from the Department of Public Health, Texas Tech University Health Sciences Center, Lubbock, TX, USA.

Since there is a significant overlap of the risk factors for ocular diseases and cardiovascular disease, the investigators recommended that screening for ocular diseases be incorporated into existing clinical and population-based screenings for cardiovascular diseases.

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