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Rising sea levels started in the 60s

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According to a study conducted by researchers from the University of Siegen, Germany, sea level rise would have started as early as the 60s of the last century. The study, published in Nature Climate Change, made use of various data relating to phenomena such as coastal tides and data from satellites.

In particular since the early 90s of the last century, satellites around the Earth have begun to measure the sea level with extreme precision, as reported by Sönke Dangendorf, researcher at the German University and principal author of the study, who adds: “So far it has not been clear when this acceleration began, in which region it was started and which processes contributed most to it. The answer to these questions was hampered by the fact that before the advent of satellite altimetry in 1992, our knowledge was based mainly on a few hundred tide gauges that record sea level along the coasts of the world and that our available approaches to reconstructing sea levels globally from these measurements were too inaccurate.”

The new approach, based on data relating to tidal registers and those provided by satellites, shows that the acceleration of sea-level rise began already in the 60s when the level itself began to increase by just under a millimeter per year (60 years), an acceleration that then reached more than 3 mm per year today, as reported by Carling Hay, geophysicist at Boston College and another author of the study.

The researchers also found that most of this level rise comes from the southern hemisphere, particularly from the subtropical southeastern marine areas of Australia and New Zealand. In these regions, this acceleration is even five times greater than the global average.

This differentiation, according to the same researchers, is due to the changing winds strongly influencing sea levels. They move northward from the warm masses of the ocean waters and control the absorption of heat by the underlying ocean, as Dangendorf explains: “When the westerly winds of the southern hemisphere intensify, more heat is pumped from the atmosphere into the ocean, leading to an expansion of the water column and therefore to an increase in the global sea level.”

Bill Stern

I am a professor of Biology at Marquette University and the founder of The Chunk. Throughout my life I have always had a strong interest in science and learning more about how the world works, and have always wanted to eventually become a science popularizer and educator myself. The Chunk, along with my responsibilities as a professor, is my attempt at improving science education and literacy.

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Nuclei of half-destroyed planets from stars detectable by radio telescopes

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There are stars that, after burning all their “fuel,” turn into so-called “white dwarfs” but project their outer layers outward before performing this transformation. This material, projected at very high speed, destroys nearby objects and also strongly damages the planets by removing the outer layers of the latter in addition to the atmospheres.

According to a study by researchers at the University of Warwick, published in Monthly Notices of the Royal Astronomical Society, the remaining nuclei of these planets can “survive” for a necessary time, from 100 million to a billion years, so that they can be detected by our telescopes.

This is not an absolute novelty: already in the early 90s, Alexander Wolszczan of Pennsylvania State University discovered one of these planets around a pulsar using a method to detect radio waves emitted by the star.

Researchers at the University of Warwick intend to improve this method to detect the magnetic field that forms between a white dwarf and a planetary nucleus in orbit around it. The magnetic field can, in fact, form a unipolar inductor circuit in which the remaining nucleus of the planet acts as a conductor thanks to the fact that inside the nucleus there are more than anything metallic compounds.

This is a real circuit whose radiations are emitted as radio waves that can be detected by terrestrial radio telescopes. Among other things, an effect of this kind has already been noted between Jupiter and one of his moons, Io.

According to Dimitri Veras, one of the authors of the study, “There is a weak point to detect these planetary nuclei: a nucleus too close to the white dwarf would be destroyed by tidal forces and a nucleus too far away would not be detectable. Also, if the magnetic field is too strong, it would push the core into the white dwarf, destroying it. Therefore, we should only look for planets around the white dwarf ones with weaker magnetic fields at a distance of about 3 solar rays, the distance Mercury-Sun.”

In any case, finding the only nucleus of a “naked” planet would represent a very important discovery that would help to discover the history of star systems as well as allowing you to take a look at the future history of our solar system and specifically of our planet which should not be very different.

Bill Stern

I am a professor of Biology at Marquette University and the founder of The Chunk. Throughout my life I have always had a strong interest in science and learning more about how the world works, and have always wanted to eventually become a science popularizer and educator myself. The Chunk, along with my responsibilities as a professor, is my attempt at improving science education and literacy.

3560 Sycamore Lake Road, Mayville Wisconsin, 53050
920-387-9926
[email protected]
Bill Stern
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Scientists discover genes involved in the life extension of fruit flies

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A group of Russian geneticists studied the Drosophila melanogaster, also called “fruit fly,” a model organism widely used in the research world as its genome is very well known and contains genes related to 40% of human diseases.

Moreover other characteristics, like the duration of the life of only a couple of months and the fact that this insect has two sexes, unlike other creatures like the nematodes, push more and more the researchers to use them during the experiments in order then to make correlations with the human beings. It is also the case of this study, published in Scientific Reports, which analyzed the genetic activity of the fruit fly to better understand the biology underlying the aging of its longevity.

Specifically, they used a Drosophila strain bred with the partially suppressed E (z) gene. It is a gene that influences the activity of other genes. The flies with this mutated gene show a considerably longer lifespan than the others and present greater resistance to adverse environmental conditions.

The researchers not only confirmed the positive effect of this mutation that allows fruit flies to extend their lives by 22-23% but they also discovered a positive effect on fertility as Alexey Moskalev, one of the authors of the study, explains: “It is known that in Drosophila, the extension of lifespan induced by mutation is often associated with reduced reproduction. But in our case, we have seen an increase in mutant female fertility in all age groups.”

They then discovered 239 genes involved in the mutation as well as in the midge’s metabolism as the scientist himself explains: “We found that the mutation triggers a global alteration of metabolism. It affects carbohydrate metabolism, lipid metabolism and nucleotide metabolism, as well as the activity of the immune response genes and protein synthesis.”

Important information that could be useful for further research regarding the extension of the life of these flies and in general concerns aging and metabolism linked to human longevity.

Bill Stern

I am a professor of Biology at Marquette University and the founder of The Chunk. Throughout my life I have always had a strong interest in science and learning more about how the world works, and have always wanted to eventually become a science popularizer and educator myself. The Chunk, along with my responsibilities as a professor, is my attempt at improving science education and literacy.

3560 Sycamore Lake Road, Mayville Wisconsin, 53050
920-387-9926
[email protected]
Bill Stern
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Mini human liver created in the laboratory to simulate diseases and study them

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Miniature cultured human liver labs were created by a group of researchers from the University of Pittsburgh School of Medicine. The “mini livers” could help to simulate the progressions of various liver diseases and therefore to test their therapies.

The researchers transformed genetically modified human skin cells into 3D liver tissue in “stripped” mouse livers of their own cells. Real functional 3D mini livers have therefore blossomed in the laboratory with lots of blood vessels and structural features of a normal human liver.

Researchers have already managed to mimic in particular non-alcoholic fatty liver disease. This condition sees the accumulation of fatty parts in the liver, a condition which in turn leads to very serious diseases such as cirrhosis or liver failure.

This is the first time that genetically modified human “mini livers” are created, as recalled by Alejandro Soto-Gutierrez, professor of pathology in Pittsburgh and senior author of the study. This is an important result because very often the experiments that are carried out on animals, mainly on mice, even if promising, do not turn out to be effective in clinical studies on humans.

This is because, of course, “mice are not human,” as Soto-Gutierrez himself recalls. There are some important differences between us and them, including mutations that predispose us to specific diseases, which is not possible to study in mice.

Bill Stern

I am a professor of Biology at Marquette University and the founder of The Chunk. Throughout my life I have always had a strong interest in science and learning more about how the world works, and have always wanted to eventually become a science popularizer and educator myself. The Chunk, along with my responsibilities as a professor, is my attempt at improving science education and literacy.

3560 Sycamore Lake Road, Mayville Wisconsin, 53050
920-387-9926
[email protected]
Bill Stern
Continue Reading

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