scholarly journals Сhiral and Racemic Fields Concept for Understanding of the Homochirality Origin, Asymmetric Catalysis, Chiral Superstructure Formation from Achiral Molecules, and B-Z DNA Conformational Transition

Symmetry ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 649 ◽  
Author(s):  
Valerii A. Pavlov ◽  
Yaroslav V. Shushenachev ◽  
Sergey G. Zlotin

The four most important and well-studied phenomena of mirror symmetry breaking of molecules were analyzed for the first time in terms of available common features and regularities. Mirror symmetry breaking of the primary origin of biological homochirality requires the involvement of an external chiral inductor (environmental chirality). All reviewed mirror symmetry breaking phenomena were considered from that standpoint. A concept of chiral and racemic fields was highly helpful in this analysis. A chiral gravitational field in combination with a static magnetic field (Earth’s environmental conditions) may be regarded as a hypothetical long-term chiral inductor. Experimental evidences suggest a possible effect of the environmental chiral inductor as a chiral trigger on the mirror symmetry breaking effect. Also, this effect explains a conformational transition of the right-handed double DNA helix to the left-handed double DNA helix (B-Z DNA transition) as possible DNA damage.

Author(s):  
G. E. Volovik

AbstractWe consider the possibility of the scenario in which the P, T and Lorentz symmetry of the relativistic quantum vacuum are all the combined symmetries. These symmetries emerge as a result of the symmetry breaking of the more fundamental P, T and Lorentz symmetries of the original vacuum, which is invariant under separate groups of the coordinate transformations and spin rotations. The condensed matter vacua (ground states) suggest two possible scenarios of the origin of the combined Lorentz symmetry, and both are realized in the superfluid phases of liquid $$^3$$ 3 He: the $$^3$$ 3 He-A scenario and the $$^3$$ 3 He-B scenario. In these scenarios, the gravitational tetrads are considered as the order parameter of the symmetry breaking in the quantum vacuum. The $$^3$$ 3 He-B scenarios applied to the Minkowski vacuum lead to the continuous degeneracy of the Minkowski vacuum with respect to the O(3, 1) spin rotations. The symmetry breaking leads to the corresponding topological objects, which appear due to the nontrivial topology of the manifold of the degenerate Minkowski vacua, such as torsion strings. The fourfold degeneracy of the Minkowski vacuum with respect to discrete P and T symmetries suggests that the Weyl fermions are described by four different tetrad fields: the tetrad for the left-handed fermions, the tetrad for the right-handed fermions, and the tetrads for their antiparticles. This may lead to the gravity with several metric fields, so that the parity violation may lead to the breaking of equivalence principle. Finally, we considered the application of the gravitational tetrads for the solution of the cosmological constant problem.


2014 ◽  
Vol 29 (26) ◽  
pp. 1450145 ◽  
Author(s):  
E. Bittencourt ◽  
S. Faci ◽  
M. Novello

This paper is an extension for spinor fields the recently developed Dynamical Bridge formalism which relates a linear dynamics in a curved space to a nonlinear dynamics in Minkowski space. This leads to a new geometrical mechanism to generate a chiral symmetry breaking without mass, providing an alternative explanation for the absence of right-handed neutrinos. We analyze a spinor field obeying the Dirac equation in a curved space which is constructed by its own current. This way, both chiralities of the spinor field satisfy the same dynamics in the curved space. Afterward, the dynamical equation is re-expressed in terms of the flat Minkowski space and then each chiral component behaves differently. The left-handed part of the spinor field satisfies the Dirac equation while the right-handed part is trapped by a Nambu–Jona-Lasinio type potential.


1993 ◽  
Vol 08 (11) ◽  
pp. 1011-1020 ◽  
Author(s):  
A. O. BARUT ◽  
G. ZIINO

The neutrino problem is set anew in the light of a reformulation of the Dirac field theory that provides a natural account for the effect commonly interpreted as 'P-violation', and restores P-mirror symmetry. A two-component (left-handed) neutrino field is automatically derived, whose P-mirror image does not correspond to a 'missing' particle but is the (right-handed) antineutrino field.


In current forensic medicine practice, the need for the development of new, scientifically based approaches and methods of forensic medical identification is still very important. The number of left-handed people in the world varies from 5 to 30 %, and it can be useful in forensic practice. The possibility of establishing a dominating hand based on the intensity of dental caries (CFE - CARIES-FILLIN-EXTRACTION index) was studied. Taking into consideration the intensity of caries damage to the teeth on the right and left sides of right-handed, left-handed and ambidextras people, we offered and calculated the CFE difference index: «CFE on the right – CFE on the left». Significant differences in the CFE indexes can help to determine what hand has been predominant and it might be useful for forensic specialists.


2020 ◽  
Vol 8 (1) ◽  
pp. 38-45
Author(s):  
Mariya Sedunova ◽  
Liliya Konovalova

International potential and consequent greater competition in belt wrestling increase the significance of assessing quantitative and qualitative indicators of competitive activity of the strongest wrestlers in the world. It is important to identify the sport development trends and to search for effective ways and tools for achievement of the sport excellence. Purpose: to reveal the features of efficient competitive activities of the world leading wrestlers on the basis of analysis of group differences in technical and tactical excellence indicators. Materials and methods of research. We analyzed videos of 285 events with participation of 197 wrestlers competing at the Belt Wrestling World Championship 2019 in Kazan. We registered the following indicators of competitive activity: the total and average number of fighting techniques, including techniques executed to the right and to the left side within 4 minutes of combat; number and types of technical actions of competition winners among men and women. Research results and discussion. The paper focuses on the comparative analysis of technical and tactical skills of men and women, the winners of the Belt Wrestling World Championship. The research revealed distinguishing features of the winner’s technical toolkit including the diversity of technical and tactical actions, a balance in the knowledge of the right and left-handed techniques. At the same time, the analysis of technical and tactical actions in women wrestling shows the backlog of female athletes in these components of technical fitness.


2019 ◽  
Vol 12 (3) ◽  
pp. 229-237 ◽  
Author(s):  
Alban Revy ◽  
François Hallouard ◽  
Sandrine Joyeux-Klamber ◽  
Andrea Skanjeti ◽  
Catherine Rioufol ◽  
...  

Objective: Recent gallium-68 labeled peptides are of increasing interest in PET imaging in nuclear medicine. Somakit TOC® is a radiopharmaceutical kit registered in the European Union for the preparation of [68Ga]Ga-DOTA-TOC used for the diagnosis of neuroendocrine tumors. Development of a labeling process using a synthesizer is particularly interesting for the quality and reproducibility of the final product although only manual processes are described in the Summary of Product (SmPC) of the registered product. The aim of the present study was therefore to evaluate the feasibility and value of using an automated synthesizer for the preparation of [68Ga]Ga-DOTA-TOC according to the SmPC of the Somakit TOC®. Methods: Three methods of preparation were compared; each followed the SmPC of the Somakit TOC®. Over time, overheads, and overexposure were evaluated for each method. Results: Mean±SD preparation time was 26.2±0.3 minutes for the manual method, 28±0.5 minutes for the semi-automated, and 40.3±0.2 minutes for the automated method. Overcost of the semi-automated method is 0.25€ per preparation for consumables and from 0.58€ to 0.92€ for personnel costs according to the operator (respectively, technician or pharmacist). For the automated method, overcost is 70€ for consumables and from 4.06€ to 6.44€ for personnel. For the manual method, extremity exposure was 0.425mSv for the right finger, and 0.350mSv for the left finger; for both the semi-automated and automated method extremity exposure were below the limit of quantification. Conclusion: The present study reports for the first time both the feasibility of using a [68Ga]- radiopharmaceutical kit with a synthesizer and the limits for the development of a fully automated process.


Author(s):  
Evan Osborne

Does humanity progress primarily through leaders organizing and directing followers, or through trial and error by individuals free to chart their own path? For most of human history ruling classes had the capacity and the desire to tightly regiment society, to the general detriment of progress. But beginning in the 1500s, Europeans developed a series of arguments for simply leaving well enough alone. First in the form of the scientific method, then in the form of free expression, and finally in the form of the continuously, spontaneously reordered free market, people began to accept that progress is hard, and requires that an immense number of mistakes be tolerated so that we may learn from them. This book tells the story of the development of these three ideas, and for the first time tells of the mutual influence among them. It outlines the rise, and dramatic triumph, of each of these self-regulating systems, followed by a surprising rise in skepticism, especially in the economic context. Such skepticism in the 20th century was frequently costly and sometimes catastrophic. Under the right conditions, which are more frequent than generally believed, self-regulating systems in which participants organize themselves are superior. We should accept their turbulence in exchange for the immense progress they generate.


Author(s):  
Andrew McNeillie
Keyword(s):  

It is now widely acknowledged, and far beyond Ireland, that Tim Robinson’s two volumes jointly known as Stones of Aran (‘Pilgrimage’ and ‘Labyrinth’) are modern classics, exemplary in every way of how to write about place and to do so with a formal, literary accomplishment that more than earns the right to nod at Ruskin’s own classic. In 2012, Robinson went back to Árainn, the largest of the three islands, for the first time in nearly ten years. He did so at the urging of Andrew McNeillie, with whom he spent two and a half days revisiting old haunts. This chapter makes account of the occasion and uses, in the process, a unique document provided by Robinson as an experiment in annotating his work. This prompts McNeillie to investigate some of his own annotations and footnotes to Aran.


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