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Recent Results on Computational Molecular Modeling of The Origins of Life

Mayen Juan Francisco Carrascoza, Błażewicz Jacek

Foundations of Computing and Decision Sciences

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2020

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Vol. 45, No. 1

35--46

EN

In the last decade of research in the origins of life, there has been an increase in the interest on theoretical molecular modeling methods aimed to improve the accuracy and speed of the algorithms that solve the molecular mechanics and chemical reactions of the matter. Research on the scenarios of prebiotic chemistry has also advanced. The presented work attempts to discuss the latest computational techniques and trends implemented so far. Although it is difficult to cover the full extent of the current publications, we tried to orient the reader into the modern tendencies and challenges faced by those who are in the origins of life field.

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Bariery techniczne ewolucji sterowanej przez dobór naturalny

Rucki M.

Mechanik

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2015

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R. 88, nr 3CD

309--316

PL

W artykule omówiono niektóre problemy techniczne, jakie pojawiałyby się w trakcje realizacji procesu ewolucji biologicznej sterowanej przez przypadkowe mutacje i dobór naturalny. Podane przykłady dotyczą ewolucji aparatu wizyjnego od plamki światłoczułej do oka kręgowca, przekształcenia łuski gada w pióro ptaka oraz wydłużenia szyi żyrafy. W połączeniu z niemożnością techniczną nawet celowego ożywienia materii nieżywej, bariery te wskazują na niemożliwość zachodzenia procesu ewolucji biologicznej, prowadzącej do powstania życia i jego samoczynnego rozwoju od form „prostych” do bardziej złożonych.

EN

In the article, there are presented some technical problems that would appear during biological evolution driven by random mutations and natural selection. The examples concern with evolution of the visual apparatus from a light-sensitive point to the fully developed vertebrate eye, transformation of the reptile scale into the bird’s feather, and the elongation of the giraffe’s neck. Taking into consideration technological impossibility of making non-living matter to live, even intentionally, those obstacles indicate that the process of biological evolution with appearance of life by chance and its emergence into various forms from one or few primordial ancestors is virtually impossible.

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Chemia radiacyjna w eksploracji Marsa

Zagórski Z. P.

Wiadomości Chemiczne

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2005

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[Z] 59, 5-6

469--488

EN

The discussion of chemical reactions caused by ionizing radiation is started, as usual, with the nature of the object which absorbs the energy. First, the composition (CO2 = 95.3%) and density of martian atmosphere is discussed; the latter is low, 120 times smaller than over the Earth atid does not protect the surface of Mars from ionizing radiations. The atmosphere over the Earth secures the shield equivalent to 3 m of concrete, with many positive consequences for the Life on Earth. In addition, high energy protons from the Sun are diverted magnetically around the Earth, and that is not the case around the Mars. The radiolysis of Martian atmosphere starts with formation of CO2 as the primary product of single ionization spurs. The multi-ionization spurs can yield exotic carbon-oxygen compounds, not explored yet. Anyway, the radiolysis of martian atmosphere is completely different from the case of Earth, where the primary product is N* ion-radical. The lack of water vapor over Mars prevents the formation of an analogue to acid rains, and of creation of many other compounds. The most interesting feature of Martian regolith is the possibility of the presence of hydrated minerals, which could have been formed milliards years ago, when (probably) water was present on Mars. Water present in the crystalline lattice undergoes only limited radiolysis, as it is known from the case of concrete, produced as biological shield build on Earth, around the sources of ionizing radiation. Formation of natural hydrated silicates on Mars was possible, therefore survival of traces of H2O on Mars is possible. However, this kind of water cannot be recovered easily, to be used by Mars explorers. The interface of the atmosphere and the regolith is probably the site of many chemical reactions. Very intensive UV, which includes part of the vacuum UV, can cause reduction of carbon dioxide to methane, recently discovered in traces over Mars, hopefully, but erroneously connected, in the mode of wishful thinking, to the Life. Minerals like sodalite, discovered on Mars can contribute as reagents in the mentioned reaction, and could be the source of hydrogen. Conclusions are dedicated to questions of the live organisms connected with exploration of Mars; from microorganisms, comparatively resistant to ionizing radiation, to human beings, considered not to be fit to manned flight, survival on Mars and return to Earth. The genius of Mankind which is able to create effective means of exploration over the distance of millions of kilometers, should be a satisfaction more important than the extremely expensive presence of man or woman on Mars.

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Radiation chemistry in exploration of Mars

Zagórski Z.

Nukleonika

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2005

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Vol. 50,suppl.2

59-63

EN

Problems of exploration of Mars are seldom connected with radiation research. Improvements in such approach, more and more visible, are reported in this paper, written by the present author working on prebiotic chemistry and origins of life on Earth. Objects on Mars subjected to radiation are very different from those on Earth. Density of the Martian atmosphere is by two orders smaller than over Earth and does not protect the surface of Mars from ionizing radiations, contrary to the case of Earth, shielded by the equivalent of ca. 3 meters of concrete. High energy protons from the Sun are diverted magnetically around Earth, and Mars is deprived of that protection. The radiolysis of martian "air" (95.3% of carbon dioxide) starts with the formation of CO2 +, whereas the primary product over Earth is N2 + ionradical. The lack of water vapor over Mars prevents the formation of many secondary products. The important feature of Martian regolith is the possibility of the presence of hydrated minerals, which could have been formed milliards years ago, when (probably) water was present on Mars. The interface of the atmosphere and the regolith can be the site of many chemical reactions, induced also by intensive UV, which includes part of the vacuum UV. Minerals like sodalite, discovered on Mars can contribute as reagents in many reactions. Conclusions are dedicated to questions of the live organisms connected with exploration of Mars; from microorganisms, comparatively resistant to ionizing radiation, to human beings, considered not to be fit to manned flight, survival on Mars and return to Earth. Pharmaceuticals proposed as radiobiological protection cannot improve the situation. Exploration over the distance of millions of kilometers performed successfully without presence of man, withstands more easily the presence of ionizing radiation.