Seagulls carry infectious bacteria for humans according to a new study

According to a study published in the Journal of Antimicrobial Chemotherapy, seagulls could represent one of the main vehicles of infectious bacteria for humans in the future, in particular those bacteria resistant to drugs and antibiotics.

The research, carried out by scientists at the Murdoch University in Perth, found that 20% of the 550 Australian gulls analyzed were carriers of infectious bacteria for humans. The seagulls themselves would become infected by coming into contact with excrement or human organic waste. Seagulls are in fact used to frequent landfills and sewer spill points and the like in search of food or nutrients.

In particular, gulls carried specimens of Escherichia coli, something that the researchers themselves found unusual. Other bacteria that seagulls carried could also cause urinary tract infections and sepsis.

The risk of a seagull transmitting an infection to a human being is still unlikely according to Mark O’Dea, a researcher who carried out the study and made some statements to the AFP.

However, the increase in these birds in the inhabited areas and the increasingly frequent contacts they have with our organic waste do not bode well in this regard.

The speed of universe expansion has been more accurately calculated

A group of researchers from Princeton has announced, through a work presented on Nature Astronomy, to have calculated more precisely the Hubble constant, or the speed with which the universe is expanding in relation to the distance between the galaxies.

Currently, the methods used to calculate this constant are basically two: that which is based on the analysis of the cosmic background radiation and that relating to the explosions of large stars very far from us.

However, these are two methods that do not agree: the first method, the one that analyzes the cosmic background radiation, reveals that the universe is expanding faster than can be calculated with the second method. It is clear that one of them is wrong, says Kenta Hotokezaka, a researcher at Princeton and one of the authors of the study, who used a new method based on the analysis of the fusion of two neutron stars.

These are very powerful energetic events that see two neutron stars collide at very high speed before merging. This event emits very strong gravitational waves that can also be intercepted on Earth. Just the interception of one of these events, which took place on August 17, 2017, was used by Hotokezaka and colleagues to calculate the speed of expansion of the universe.

The gravitational waves that occur during these events, in fact, create a characteristic pattern that has been called “standard siren.” Researchers also used data from various radio telescopes around the world to improve the resolution of radio images related to this cosmic explosion so that the final resolution was so high that it could be compared to that of a camera that distinguishes individual hair on the head of someone from 5 km away, as specified by Adam Deller, Swinburne University of Technology, Australia, another author of the study.

Then using a supercomputer, they also analyzed the most minute changes in the position and shape of this radiation, managing to determine the orientation of neutron stars.

Comparing this data with the speed with which the galaxy containing these two neutron stars moved away from ours, they therefore performed a better measurement of the Hubble constant. The speed of the expansion of the universe is now estimated between 65.3 and 75.6 kilometers per second per megaparsec, a more precise measurement than previously calculated.

However, for researchers, the level of precision in this estimate is still not enough: they intend to insist on analyzing more collisions like the one they used for this study.

Scientists discover that ghrelin, the hunger hormone, improves memory

A group of researchers has discovered that ghrelin, already defined as “the hunger hormone” because it is responsible for transmitting hunger signals from the intestine to the brain, can improve memory.

This substance, produced in the stomach, binds to particular receptors of the vagus nerve, a nerve that connects the intestine to the brain. According to Scott Kanoski, senior author of the study, ghrelin helps the vagus nerve promote memory, at least in the laboratory mice on which the experiments were conducted.

By blocking ghrelin signaling in rats using a method called RNA interference, the researchers found that mice had worse results in episodic memory tests, tests that involve having to remember when something happened or where it is. In the case of these experiments, the rats had to remember where an object was located in a specific location.

Furthermore, when the ghrelin signal was interrupted through the vagus nerve, rodents tended to eat more frequently but consumed smaller amounts with each meal.

According to the researchers, this characteristic would also be related to the problem of reduced memory as “deciding to eat or not to eat is influenced by the memory of the previous meal,” as specified by Elizabeth Davis, the lead author of the study.

These findings could prove useful for improving memory capacity in humans.

Drinking matcha tea can reduce anxiety according to study

A new study highlights the positive qualities of matcha tea, a quality of Japanese tea that is becoming increasingly popular. Originally from China and made from the Camellia sinensis green tea plant, this tea has a particular process with regards to its preparation: the leaves are steamed, then dried and then ground to obtain a very fine powder.

In Japan, this tea has a long history behind it even as a medicine or relaxing compound even though there is little scientific evidence to emphasize this.

The new research, conducted by Japanese scientists at the University of Kumamoto, shows that this particular quality of tea can help reduce anxiety in mice.

The mechanisms that help in this regard are related to the activation of dopamine D1 receptors and serotonin 5-HT 1A receptors. These are two types of receptors already known because they are linked to anxious behavior.

The researchers conducted a rodent anxiety test that sees the most anxious subjects spend more time in the walled, and therefore safer, areas of a particular maze.

The researchers first made some of the mice extract matcha extract and then conducted the experiment: the results clearly showed the reduction in anxiety in mice that took the extract.

Yuki Kurauchi, the lead author of the study, admits that further epidemiological research will be conducted but these studies show at the time that matcha tea “can be very useful for the human body.”

New satellite system identifies the smallest deformations to prevent bridge collapses

A new satellite system will help to identify bridges that could collapse. Researchers at the Jet Propulsion Laboratory (JPL) of NASA and the University of Bath have in fact developed a new pre-alarm system that uses satellite images to identify even the smallest deformations or small movements in bridge structures in order to identify the risk of collapse.

The idea came when scientists verified 15 years of satellite images of the Morandi Bridge in Genoa, of which a large section collapsed in August last year causing the death of 43 people. In the study, published in Remote Sensing, it is shown how the bridge, in these satellite images, already showed signs of deformation in the months that preceded the collapse. The system, in fact, is able to intercept the deformations of the structures with a millimetric precision.

“We have shown that it is possible to use this tool, in particular the combination of different data from satellites, with a mathematical model, to detect the first signs of collapse or deformation,” says Giorgia Giardina, a researcher at the University of Bath and one of the authors of the study.

The system would be better able to detect signs of deformation or structural movement in bridges, but also in other buildings or structures, compared to today’s monitoring systems that substantially detect these modifications only at specific points, ie those in which they are positioned sensors.

Instead, this new technique involves an almost real-time monitoring of the entire structure with unprecedented frequency and accuracy, as also emphasized by Pietro Milillo, researcher of the JPL and another author of the study. Combining this technique with other more “classic” techniques, the potential for bridge collapse prevention activities would become even higher.

This is a system whose conception has been made possible thanks to the major advances in satellite technology that have taken place in recent years.

In this case, the researchers combined the radar satellites of the COSMO-SkyMed constellation of the Italian Space Agency (ASI) and the Sentinel-1a and 1b satellites of the European Space Agency (ESA).

Thanks to the radar data of these satellites, it is possible to construct a very detailed and specific 3D image of a bridge or any building on the earth’s surface.

Small marine worm emits one of the ocean’s loudest noises

A small worm emits one of the loudest noises emitted by animals in the oceans, so strong that it could break even small glass vessels. The study analyzed the Leocratides kimuraorum, marine worms a little less than three cm long discovered for the first time in 2017.

These worms, which live in the small grooves of the hexattellellid sponges, were identified off the coast of Japan. But only when they were brought to the laboratory did the researchers discover the strangest feature related to these small animals. When they fight each other, they strangely contract their bodies by jumping “head down” towards the enemy.

This specific movement is the cause of the emission of a loud popping sound, similar to the noise emitted when ripping off the champagne. The researchers detected this municipality through specific underwater microphones. These are not the only small marine animals that produce such loud noises: even shrimps usually “snap” with their bodies but do so by quickly closing their claws.

The Leocratides kimuraorum, on the other hand, have no hard part because they boast a completely soft body. They simply manage to generate this loud noise through very high pressure by twisting the body which, at the simple contraction of the muscles, emits noise.

New method for detecting extrasolar planets using gravitational waves

A group of researchers confirms that a new method for detecting extrasolar planets using gravitational waves could be very useful indeed. Specifically, this method would apply to the identification of those exoplanets that orbit binary systems of white dwarfs, both in the Milky Way and in the nearby Magellanic Clouds.

The method is based on the observations of gravitational waves, something that would allow the LISA observatory, a space observatory consisting of three satellites whose mission should be launched in 2034, to detect planets with at least 50 land masses. To date, the techniques most used to identify extrasolar planets are those related to the planet’s transit system in front of their own star from our point of view and that which is based on the interception of the gravitational influence that the planet can have on its own star.

In the new article, which appeared in Nature Astronomy , Nicholas Tamanini, a researcher at the Max Planck Institute for Gravitational Physics in Potsdam, and Camilla Danielski, a researcher at the French Commission for Atomic Energy and Alternative Energy (CEA) in Saclay, state that the inherent limitations of these methods can be overcome by resorting to gravitational wave analysis.

As the same Tamanini explains, the LISA observatory will measure, after the launch of the mission, the gravitational waves of many thousands of white dwarf binary systems. However, if in the vicinity of these latter orbits a fairly large planet, the same gravitational waves will appear different and this change can be analyzed to acquire information on the planet, as well as its own presence.