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- Code Scientist: The shortest genome and the rebirth of extinct species
Code Scientist: The shortest genome and the rebirth of extinct species
Russian chemists have figured out how to make green fuel from water cheaper, and British biologists have created a bacterium with the shortest DNA. An international team of scientists has found evidence of the beginning of the Ice Age due to the arrival of a comet. In addition, Russian astrophysicists have studied the impact of meteor showers on the safety of lunar missions, and geneticists have restored the genome of extinct sea lions, which will help revive the population. These and other events from the world of science can be found in the weekly Izvestia collection.
Extinct sea lions will be revived by Russian experts
Scientists from the European University of St. Petersburg and several research organizations in South Korea have conducted the first large-scale study of the genetic history of Dokdo sea lions. These are extinct marine mammals that were widespread in the southern Sea of Japan until the early 20th century.
— The population of Tokto sea lions used to be tens of thousands of individuals, but in the first quarter of the XX century there was a sharp decrease in their numbers. The reason is the intensive extraction of meat, skins and fat of these animals, which is associated with the period of occupation of Korea by Japan. In particular, females and cubs were exterminated for profit. In the 1950s, there were only 50-60 Tokto sea lions, and the last time a representative of this species was seen alive was in 1974," Artyom Nedoluzhko, co-author of the study and scientific director of the paleogenomics laboratory at the European University in St. Petersburg, told Izvestia.
According to him, in the course of their work, scientists have made a number of discoveries. Among other things, it was confirmed that Dokdo sea lions are the oldest branch, which was the first to stand out from the common trunk, and then other species descended from it — California and Galapagos sea lions. Another achievement is related to the identification of genetic traces of crossbreeding of Tokto sea lions with related species — northern fur seals and sea lions. Due to this gene transfer (introgression), animals have adapted better to changing conditions.
As Artyom Nedoluzhko noted, scientific work will help in the future to revive an extinct species using gene editing.
Russia has modeled the impact of the Perseid flow on the safety of lunar missions
Researchers from Russia and Finland have created a computational model to describe the impact of the Perseid meteor shower on the lunar exosphere, the plasma environment of the satellite. Scientists from the P.K. Sternberg State Astronomical Institute, Ural Federal University, the Institute of Astronomy of the Russian Academy of Sciences and other organizations took part in the scientific work.
The Perseids are a plume of dust particles from Comet Swift—Tuttle that reach the Earth's atmosphere once a year and cause a "star shower". They also end up on the moon. At the same time, as the simulation showed, a large number of meteoroid particles with a mass of up to 5-10 millionths of a gram per square centimeter crash into the lunar exosphere at high speed. This significantly affects its composition and condition, making it more sparse.
— All objects of the Solar system that do not have an atmosphere are exposed to this effect. These phenomena must be taken into account when preparing lunar missions. Sometimes collisions of the smallest particles cause visible damage to machinery. Although the dust is very fine, it has a high velocity. And our model can predict where and when to encounter them, and not fly there. Choose the landing sites and the schedule of the expedition," said Maria Gritsevich, senior researcher at the UrFU Extra Terra Consortium Scientific Laboratory.
The model will also allow us to better understand how the Solar system developed, the scientist noted, since comets are an important source of information about these processes.
Magnetic nanoparticles will accelerate the production of green hydrogen
Scientists from ITMO University have come up with a reactor that will make the production of hydrogen from water faster and cheaper. The proposed technology will speed up the process six times, while reducing energy consumption by 15%.
According to experts, the main innovation of the installation is modified electrodes with magnetic iron and cobalt nanoparticles. They help water molecules break down faster, which reduces energy costs.
— Magnetic nanoparticles affect the electronic state of water intermediates so that they react faster and more efficiently. This reduces the amount of energy consumed to activate these processes. As a result, the production of 1 kg of hydrogen does not require 57.3 kWh of electricity, as before, but 48.8 kWh," Ilya Shabalkin, one of the authors of the development, a graduate student of the chemical and biological cluster, a junior researcher at ITMO, told Izvestia.
He clarified that the device has already been assembled in the laboratory, printed on a 3D printer and is ready for testing at a real factory.
As the scientist explained, hydrogen is a promising type of fuel, but its use is limited by the high cost of environmentally safe production of this gas. Electrolysis of water using electricity from renewable sources is called green because this process is not accompanied by greenhouse gas emissions.
Scientists have found evidence of the comet's "guilt" at the beginning of the Ice Age
Russian scientists as part of an international team have discovered new evidence of the cometary version of the beginning of the Ice Age.
According to her, about 12,800 years ago, a sharp cold snap on our planet occurred as a result of the fall of a large cosmic body (comet or asteroid). It exploded upon entering the dense layers of the atmosphere. As a result, many particles were formed. They blocked out sunlight and reflected heat from the Ground.
Until recently, traces of this dust were found only in soil and glaciers. However, scientists lacked the evidence found on the ocean floor. To close this gap, a team of researchers from the University of South Carolina (USA), the Institute of Physics of the Earth of the Russian Academy of Sciences and other organizations analyzed cores that were taken from the bottom of the Baffin Sea off the coast of Greenland.
In the process of studying the samples, scientists revealed the presence of particles containing nickel and iron, which correspond in composition to cometary dust. In addition, the particles were found together with so-called microspherules, which contain silica and iron.
"These microspherules were probably formed as a result of explosions in the atmosphere at low altitude and collisions of comet fragments with the surface and were widely dispersed," the scientists noted in a scientific article on the study.
In their opinion, the discovery of an impact layer in deep-sea sediments highlights the potential of oceanic data to expand our understanding of this catastrophic event and its climatic consequences.
The shortest DNA code will help create invulnerable bacteria.
Scientists from the Laboratory of molecular biology of the Medical Research Council (a research institute in Cambridge, UK) have created the bacterium Escherichia coli (E. coli) with a radically simplified DNA code. In the new strain, instead of the usual 64, there are only 57 codons — units of the genetic code that consist of three nucleotides. It is the most compact genome of all existing in nature.
— It was a tremendous job. The work took four years and required a lot of trial and error," said Wesley Robertson, head of research.
The main achievement, the scientists noted, is to prove that life can exist with a much simpler genetic code than evolution has created. This brings the creation of fundamentally new biotechnologies closer.
For example, since in a living environment many codons duplicate each other's functions, removing unnecessary ones can make room for the creation of microorganisms with artificial DNA blocks.
Such bacteria will be able to produce fundamentally new materials and medicines that do not exist in nature. However, viruses that use a standard genetic code will not be able to infect reprogrammed cells.
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