Pioneering study shows climate played crucial role in changing location of ancient coral reefs

Pre-historic coral reefs dating back up to 250 million years extended much further away from the Earth’s equator than today, new research has revealed.

The new study, published in Nature Communications, demonstrates how changes in temperature and plate tectonics, where the positions of Earth’s continents were in very different positions than today, have determined the distribution of corals through the ages.

Although climate has often been regarded as the main driver of the location of coral reefs, this has yet to be proven due to limited fossil records. Now, for the first time, a team of international scientists used habitat modelling and reconstructions of past climates to predict the distribution of suitable environments for coral reefs over the last 250 million years.

The researchers, from the University of Vigo, in Spain, the University of Bristol and University College London in the UK, then checked their predictions using fossil evidence of warm-water coral reefs. They showed that corals in the past, from 250 to about 35 million years ago, existed much further from the equator than today, due to warmer climatic conditions, and a more even distribution of shallow ocean floor.

“Our work demonstrates that warm-water coral reefs track tropical-to-subtropical climatic conditions over geological timescales. In warmer intervals, coral reefs expanded poleward. However, in colder intervals, they became constrained to tropical and subtropical latitudes,” said first author Dr Lewis Jones, a computational paleobiologist research fellow at the University of Vigo.

No signs (yet) of life on Venus

Venus from Mariner 10 
Credit: NASA/JPL-Caltech

Researchers from the University of Cambridge used a combination of biochemistry and atmospheric chemistry to test the ‘life in the clouds’ hypothesis, which astronomers have speculated about for decades, and found that life cannot explain the composition of the Venusian atmosphere.

Any life form in sufficient abundance is expected to leave chemical fingerprints on a planet’s atmosphere as it consumes food and expels waste. However, the Cambridge researchers found no evidence of these fingerprints on Venus.

Even if Venus is devoid of life, the researchers say their results, reported in the journal Nature Communications, could be useful for studying the atmospheres of similar planets throughout the galaxy, and the eventual detection of life outside our Solar System.

“We’ve spent the past two years trying to explain the weird sulfur chemistry we see in the clouds of Venus,” said co-author Dr Paul Rimmer from Cambridge’s Department of Earth Sciences. “Life is pretty good at weird chemistry, so we’ve been studying whether there’s a way to make life a potential explanation for what we see.”

The researchers used a combination of atmospheric and biochemical models to study the chemical reactions that are expected to occur, given the known sources of chemical energy in Venus’s atmosphere.

Novel host cell pathway hijacked during COVID-19 infection

Graphic showing how the ESCPE-1 host cell pathway is hijacked by SARS-CoV-2 during the infection of human cells
Credit: Second Bay Studios

An international team of scientists, led by the University of Bristol, has been investigating how the SARS-CoV-2 virus, the coronavirus responsible for the COVID-19 pandemic, manipulates host proteins to penetrate into human cells. After identifying Neuropilin-1 (NRP1) as a host factor for SARS-CoV-2 infection, new findings published in the journal of the Proceedings of the National Academy of Sciences today 14 June describe how the coronavirus subverts a host cell pathway in order to infect human cells.

SARS-CoV-2 continues to have a major impact on communities and industries around the world. In an attempt to find innovative strategies to block SARS-CoV-2 infection, the team previously identified NRP1 as an important receptor at the surface of cells that is hijacked by SARS-CoV-2 to enhance infection.

NRP1 is a dynamic receptor that senses the microscopic cellular environment through the recognition of proteins containing specific neuropilin-binding sequences, called ligands. By mimicking this neuropilin-binding sequence, SARS-CoV-2 is able to subvert this receptor to enhance its entry and infection of human cells.

Photon twins of unequal origin

The quantum dots of the Basel researchers are different, but send out exactly identical light particles.
Credit: University of Basel, Department of Physics

Researchers have created identical light particles with different quantum dots - an important step for applications such as tap-proof communication.

Many technologies that take advantage of quantum effects are based on exactly the same photons. However, it is extremely difficult to manufacture them. Not only must the wavelength (color) of the photons exactly match, but also their shape and polarization.

A team of researchers from the University of Basel around Richard Warburton, in collaboration with colleagues from the Ruhr University in Bochum, has now succeeded in producing identical photons that come from different, widely separated sources.

Individual photons from quantum dots

In their experiments, physicists use so-called quantum dots, i.e. structures a few nanometers in semiconductor materials. Electrons are trapped in these quantum dots, which only assume very specific energy levels and can emit light when moving from one level to another. With the help of a laser pulse that triggers such a transition, individual photons can be produced at the push of a button.

Eternal matter waves

The central part of the experiment in which the coherent matter waves are created. Fresh atoms (blue) fall in and make their way to the Bose-Einstein Condensate in the center. In reality, the atoms are not visible to the naked eye.
Image processing by Scixel.

Imagining our everyday life without lasers is difficult. We use lasers in printers, CD players, pointers, measuring devices, and so on. What makes lasers so special is that they use coherent waves of light: all the light inside a laser vibrates completely in sync. Meanwhile, quantum mechanics tells us that particles like atoms should also be thought of as waves. As a result, we can build ‘atom lasers’ containing coherent waves of matter. But can we make these matter waves last, so that they may be used in applications? In research that was published in Nature this week, a team of Amsterdam physicists shows that the answer to this question is affirmative.

Getting bosons to march in sync

The concept that underlies the atom laser is the so-called Bose-Einstein Condensate, or BEC for short. Elementary particles in nature occur in two types: fermions and bosons. Fermions are particles like electrons and quarks – the building blocks of the matter that we are made of. Bosons are very different in nature: they are not hard like fermions, but soft: for example, they can move through one another without a problem. The best-known example of a boson is the photon, the smallest possible quantity of light. But matter particles can also combine to form bosons – in fact, entire atoms can behave just like particles of light. What makes bosons so special is that they can all be in the exact same state at the exact same time, or phrased in more technical terms: they can ‘condense’ into a coherent wave. When this type of condensation happens for matter particles, physicists call the resulting substance a Bose-Einstein Condensate.

Thin-film photovoltaics: Efficient and versatile in a double pack

Perowskit / CIS tandem solar cells are already converting a relatively large proportion of the incident light into electricity. Future developments can further improve efficiency.
Photo Credit: Marco A. Ruiz-Preciado, KIT

Stacking solar cells on top of each other increases efficiency. Researchers at the Karlsruhe Institute of Technology (KIT), together with partners in the EU project PERCISTAND, have now produced perovskite / CIS tandem solar cells with an efficiency of almost 25 percent - the highest for this technology to date. In addition, the material combination ensures lightness and versatility, so that the use of these tandem solar cells is also conceivable on vehicles, portable devices and foldable or rollable devices. The researchers present their work in the ACS Energy Letters journal.

Perovskite solar cells have undergone a steep development in just ten years. In terms of efficiency, they can already be compared with the long-established silicon solar cells. Perovskites are innovative materials with a special crystal structure. Researchers worldwide are currently working on making perovskite photovoltaics ready for practical use. The more electricity they generate per unit area, the more attractive solar cells are for end users.

The efficiency can be increased by stacking two or more solar cells. If each solar cell absorbs a different part of the sunlight spectrum particularly efficiently, inherent losses can be reduced and efficiency increases. This indicates how much of the incident light is converted into electricity. Thanks to their versatility, perovskite solar cells are ideal as part of such tandems. Tandem solar cells made of perovskites and silicon have achieved a record efficiency of over 29 percent - significantly higher than that of individual cells made of perovskites (25.7 percent) and silicon (26.7 percent).

Real-time Imaging of Dynamic Atom-atom Interactions

In a breakthrough, Tokyo Tech researchers have managed to observe and characterize dynamic assembly of metallic atoms using an ingenious combination of scanning transmission electron microscopy and video-based tracking. By visualizing short-lived molecules, such as metallic dimers and trimers, that cannot be observed using traditional methods, the researchers open up the possibility of observing more such dynamic structures predicted by simulations.

Chemistry is the study of bond formation (or dissociation) between atoms. The knowledge of how chemical bonds form is, in fact, fundamental to not just all of chemistry but also fields like materials science. However, traditional chemistry has been largely limited to the study of stable compounds. The study of dynamic assembly between atoms during a chemical reaction has received little attention. With recent advances in computational chemistry, however, dynamic, short-lived structures are gaining importance. Experimental observation and characterization of dynamic bonding predicted between atoms, such as the formation of metallic dimers, could open up new research frontiers in chemistry and materials science.

However, observing this bond dynamics also requires the development of a new methodology. This is because conventional characterization techniques only provide time-averaged structural information and are, thus, inadequate for observing the bonds as they are formed.

Extreme weather and climate events likely to drive an increase in gender-based violence

Aftermath of Hurricane Katrina 
Credit: NOAA Images

In a study published in The Lancet Planetary Health, a team led by a researcher at the University of Cambridge analyzed current scientific literature and found that the evidence paints a bleak picture for the future as extreme events drive economic instability, food insecurity, and mental stress, and disrupt infrastructure and exacerbate gender inequality.

Between 2000 and 2019, floods, droughts, and storms alone affected nearly 4 billion people worldwide, costing over 300,000 lives. The occurrences of these extreme events represent a drastic change, with the frequency of floods increasing by 134%, storms by 40%, and droughts by 29% over the past two decades. These figures are expected to rise further as climate change progresses.

Extreme weather and climate events have been seen to increase gender-based violence, due to socioeconomic instability, structural power inequalities, health-care inaccessibility, resource scarcity and breakdowns in safety and law enforcement, among other reasons. This violence can lead to long-term consequences including physical injury, unwanted pregnancy, exposure to HIV or other sexually transmitted infections, fertility problems, internalized stigma, mental health conditions, and ramifications for children.

A Glimpse into the Dog’s Mind: A New Study Reveals How Dogs Think of Their Toys

Many dog lovers want to know what goes on in their furry friends’ minds. Now scientists are finally getting closer to the answer. In a new study just published in the journal of Animal Cognition, researchers from the Family Dog Project (Eötvös Loránd University, University, Budapest) found out that dogs have a “multi-modal mental image” of their familiar objects. This means that, when thinking about an object, dogs imagine the object’s different sensory features. For instance, the way it looks or the way it smells.

The group of scientists assumed that the senses dogs use to identify objects, such as their toys, reflect the way the objects are represented in their minds. “If we can understand which senses dogs use while searching for a toy, this may reveal how they think about it” explains Shany Dror, one of the leading researchers of this study. “When dogs use olfaction or sight while searching for a toy, this indicates that they know how that toy smells or looks like”.

In previous studies, the researchers discovered that only a few uniquely gifted dogs can learn the names of objects. “These Gifted Word Learner dogs give us a glimpse into their minds, and we can discover what they think about when we ask them - Where is your Teddy Bear? – “explains Dr. Andrea Sommese, the second leading researcher.

Mastodon tusk chemical analysis reveals first evidence of one extinct animal’s annual migration

A mounted skeleton of the Buesching mastodon, based on casts of individual bones produced in fiberglass, on public display at the University of Michigan Museum of Natural History in Ann Arbor. The Buesching mastodon is a nearly complete skeleton of an adult male recovered in 1998 from a peat farm near Fort Wayne, Indiana. A new study, led by Joshua Miller of the University of Cincinnati and Daniel Fisher of the University of Michigan, uses oxygen and strontium isotopes from the mastodon’s right tusk to reconstruct changing patterns of landscape use during its lifetime.
Image credit: Eric Bronson, Michigan Photography

Around 13,200 years ago, a roving male mastodon died in a bloody mating-season battle with a rival in what today is northeast Indiana, nearly 100 miles from his home territory, according to the first study to document the annual migration of an individual animal from an extinct species.

The 8-ton adult, known as the Buesching mastodon, was killed when an opponent punctured the right side of his skull with a tusk tip, a mortal wound that was revealed to researchers when the animal’s remains were recovered from a peat farm near Fort Wayne in 1998.

Northeast Indiana was likely a preferred summer mating ground for this solitary rambler, who made the trek annually during the last three years of his life, venturing north from his cold-season home, according to a paper scheduled for online publication June 13 in Proceedings of the National Academy of Sciences.