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Radio telescope MeerKAT takes pictures with thousands of galaxies billions of light years away

A new image of the deep universe has been realized thanks to the data received by the MeerKAT radio telescope made by 64 antennas located in South Africa. The image shows tens of thousands of small points of light but they are not stars: each of these points is a distant galaxy and each of them could potentially contain hundreds or thousands of billions of stars.

The most interesting feature of the image, however, is that the most distant galaxies represent the weakest points of light. Acquiring data and information about these “primordial” galaxies can in fact help astronomers understand when the first stars and galaxies were born. Most stars are currently thought to have been born between 8 and 11 billion years ago, an era also known as “cosmic noon.”

It is usually very difficult to acquire light from these galaxies so far away not only because of the distance but also because of the gas clouds that can overlap and make them invisible. And this is where radio telescopes come into play, operating at a wavelength through which these gas clouds can be “surpassed” to catch a glimpse of the farthest hidden galaxies.

In fact, an international team of astronomers has succeeded in using the MeerKAT radio telescope, now sensitive enough to detect even these galaxies billions of light years away. The result is the image that can be seen on this page that represents a portion of the southern sky, comparable to that occupied by five full moons, with tens of thousands of galaxies, an area that does not contain particular radio sources whose glow could disturb the data acquisition.

Of course, as with all objects located at a certain distance, here too we can speak of a sort of “time machine” with which we can look at the past of the cosmos. And, as James Condon, one of the authors of the study and researcher at the National Radio Astronomy Observatory, USA, explains, “since only short-lived stars that are less than 30 million years old send radio waves, we know that the image is not contaminated by old stars. The radio light we see from each galaxy is therefore proportional to its speed of stellar formation at that time”.

Thanks to this image and the data collected with MeerKAT, researchers now know that during the “cosmic noon” era, even more stars were formed than previously calculated and that there are probably many more galaxies in the universe than ever theorized.

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The existence of an ancient Mayan palace more than 1000 years old in the Mexican jungle has been confirmed

A palace built by the ancient Mayan civilization more than 1000 years old that was found in the middle of the jungle in the northeast of the Yucatan Peninsula, Mexico, according to a statement by the National Institute of Anthropology and History of Mexico.

The palace, which is part of a complex that is probably much larger and which also sees the presence of a burial site, was built by the inhabitants of Kulubá, an ancient Mayan city. According to Mexican archaeologists, this palace must have been in use between 600 and 1050 AD. The palace is characterized by a length of 55 meters, a width of 15 meters and a height of 6 meters.

The discovery may offer a lot of data and information about the architectural style of the Kulubá civilization, of which very little is known. Archaeologists themselves believe that by digging further, more structures can be found, so that this site will most likely become an attraction for visitors.

The Mayan civilization, in fact, used to build temples and pyramids as well as huge stone buildings. However, it suffered a mysterious decline between 800 and 1000 A.D., decline whose houses have never been fully clarified (various hypotheses speak of intestinal wars, climatological upheavals and viral diseases).

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Freshwater megafauna in sharp decline according to study

Freshwater animals represent about one-third of all vertebrate species in the world, presenting a highly respected variety. However, it is unfortunate that life itself in the rivers, lakes and all the bodies of freshwater in the world is in sharp decline, as confirmed by new research published in Global Change Biology.

The research, in particular, has focused on freshwater megafauna, which is all those animals of a certain size that weigh at least 50 pounds. We speak, therefore, of crocodiles, large fish such as sturgeons, giant tortoises, and so on.

By gathering data on 126 species of freshwater megafauna from various parts of the world, researchers have concluded that from 1970 to 2012 these populations even decreased by 88%.
This is a double decrease compared to the heavy defections affecting terrestrial or marine vertebrate populations.

Sonja Jähnig, a researcher at the Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB), lead author of the study, talks about alarming results that confirm the already very strong concerns before this study regarding freshwater biodiversity.

The most important decreases occurred in the Indo-Malaysian ecozone (India and neighboring countries plus south-east Asia), with a 99% decrease, and in the Palearctic eco-zone (almost all of Asia, Europe and North Africa), which saw a 97% decrease.

Among the most affected species are those related to large fish such as sturgeons, salmonids and giant catfish that show an average drop of 94%. These species are followed by reptiles that show an average decrease of 72%.

The main reasons behind the decrease in the populations of these animals are due to the excessive exploitation by human beings and the loss of the flow of the rivers, a phenomenon that occurs especially when the flow of water is blocked by the dams, as recalls Fengzhi He, first author of the study and expert in freshwater megafauna.

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Important discovery made in age-related macular degeneration

An important turning point with important implications for those suffering from macular degeneration linked to the dry age (AMD): this is what the result obtained from research published on JCI Insight claims.

The researchers found that a component that lines the blood vessels of the retina, or claudin-5, may be one of the primary factors in the development of this disease. Natalie Hudson, the first author of the study, also explains this: “We were initially surprised by the fact that these blood vessels in the internal retina contributed to a pathology similar to AMD, but now it seems that their dysfunction may represent one of the first initial factors of the disease.”

Age-related macular degeneration is one of the most common causes of blindness in older people. It involves a loss of central visual acuity so that the same common daily activities become difficult to perform or impossible. There are two forms, one dry and one wet. There is some therapy for the wet one but there are no approved treatments or cures for the dry one that represents most of the cases.

This finding could be useful for new targeted approaches and new therapies focused, for example, on the integrity of retinal blood vessels, as explained by Matthew Campbell, assistant professor of genetics at the Irish institute and another author of the study.

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33% of new cases of childhood asthma in Europe caused by air pollution

Another piece of research, this time conducted by a Spanish institute, confirms that among the main factors of asthma for children is air pollution.

According to the new study, published in the European Respiratory Journal and conducted by the Institute for Global Health in Barcelona (ISGlobal), 33% of new annual cases (over 190,000 cases) of childhood asthma could be avoided if European countries “were able to reduce air pollution levels to the lowest levels recorded in the literature.”

This means that air pollution is basically the basis of one-third of children’s asthma cases. According to the study, up to 11% of new cases (over 66,000 cases) of childhood asthma could also be avoided every year if European countries “respected the WHO guidelines on air quality of PM 2.5.” The latter is a classification that indicates that fine particulate matter, essentially the powders, whose grains are fine to this point (at least 2.5 µm, or a quarter of a 100th of a millimeter) to be able to penetrate into the human lungs.

Researchers analyzed data from 18 European countries while data on exposure to air pollutants were obtained through a statistical model based on multiple measurements performed in Europe.