scholarly journals NEW OBSERVATIONS ON FLAGELLAR FINE STRUCTURE

1970 ◽  
Vol 47 (1) ◽  
pp. 159-182 ◽  
Author(s):  
Fred D. Warner
Keyword(s):  
Double Helix ◽  
Microtubule Organization ◽  
Sarcophaga Bullata ◽  
The Matrix ◽  
Matrix Region ◽  
Cilia And Flagella ◽  
Relationship Of ◽  
The Relationship ◽  
Tubule Wall ◽  
Similar Organization

The sperm flagella of the blowfly Sarcophaga bullata demonstrate the relationship of radial projections in the matrix region to the microtubule organization of the axoneme. The A microtubule of each peripheral doublet is connected to the central sheath by a series of paired radial links. The links lie along the tubule wall with a alternate spacing of about 320/560 A. The distal end of each link is enlarged into a globular head that connects via a transitional link to the helical sheath around the central microtubules. The radial link pairs are disposed in the form of a double helix with a pitch of about 1760 A. It is proposed that a similar organization is common to all cilia and flagella showing ninefold symmetry and must provide, in part, the morphological basis for motility.

scholarly journals Oculomotor activity parameters of the operator in the P300 brain computer interface and similar stimulus situations

2015 ◽  
Vol 8 (4) ◽  
pp. 134-144
Author(s):  
I.A. Basyul
Keyword(s):  
Average Length ◽  
Brain Computer Interface ◽  
Computer Interface ◽  
Similar Stimulus ◽  
The Matrix ◽  
Relationship Of ◽  
The Relationship ◽  
Visual Fixations ◽  
Oculomotor Activity ◽  
Stimulus Environment

Hypotheses about the relationship of the processes of visual perception and variations of the task in an identical stimulus environment was tested. The following tasks were tested: 1) a simple observation of the illuminations of the character in the matrix; 2) counting the number of highlights; 3) monitoring of the target symbol highlights and typing text with the P300 BCI. In a group of 14 people showed that the highest average length of visual fixation and the lowest dispersion of fixation observed for the second type of task. Statistically significant differences in the level of dispersion of visual fixations found between 1-2 and 1-3 modes; differences between the modes for the duration of fixations are at trends. Significant differences in the number of visual fixations on the target symbols wasn’t detected. The overall conclusion is the high perspective of pairing methodology brain-computer interface on the P300 wave with eye tracking to optimize the characteristics of the stimulus in the BCI environment. The differences in the parameters of oculomotor activity between the tasks reflect the level of attention concentration in the target symbols of the P300 BCI

scholarly journals Quaternion treatment of the relativistic wave equation

1937 ◽  
Vol 162 (909) ◽  
pp. 145-154 ◽  
Keyword(s):  
Wave Function ◽  
Wave Equation ◽  
Linear Functions ◽  
Relativistic Wave Equation ◽  
Relativistic Wave ◽  
Formal Representation ◽  
The Matrix ◽  
Scalar Products ◽  
Relationship Of ◽  
The Relationship

A set of matrices can be found which is isomorphic with any linear associative algebra. For the case of quaternions this was first shown by Cayley (1858), but the first formal representation was made by Peirce (1875, 1881). These were two-matrices, and the introduction of the four-row matrices of Dirac and Eddington necessitated the treatment of a wave function as a matrix of one row (as columns). Quaternions have been used by Lanczos (1929) to discuss a different form of wave equation, but here the Dirac form is discussed, the wave function being taken as a quaternion and the four-row matrices being linear functions of a quaternion. Certain advantages are claimed for quaternion methods. The absence of the distinction between outer and scalar products in the matrix notation necessitates special expedients (Eddington 1936). Every matrix is a very simple function of the fundamental Hamiltonian vectors α, β, γ , so that the result of combination is at once evident and depends only on the rules of combination of these vectors. At all stages the relationship of the different quantities to four-space is at once visible. The Dirac-Eddington matrices, the wave equation and its exact solution by Darwin, angular momentum operators, the general and Lorentz transformation, spinors and six-vectors, the current-density four-vector are treated in order to exhibit the working of this method. S and V for scalar and vector products are used. Quaternions are denoted by Clarendon type, and all vectors are in Greek letters.

Effect of Composition and Temperature on the Formation of Delta Ferrite in the Billet for P92 Steel

2011 ◽  
Vol 194-196 ◽  
pp. 1280-1286 ◽  
Author(s):  
He Min Jing ◽  
Bo Wang ◽  
Dang Sheng Xiong ◽  
Yin Geng Xu ◽  
Jun Jie Wang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Strong Relationship ◽  
Delta Ferrite ◽  
P92 Steel ◽  
Heat Temperature ◽  
Three Samples ◽  
The Matrix ◽  
High Temperature Steam ◽  
Relationship Of ◽  
The Relationship

The use of P92 is becoming more and more widespread in high temperature steam pipe of super-ultracritical power station boilers, it’s key material for the manufacture of boiler’s four main pipes. The properties of P92 are closely related with its microstructure, and the microstructure of P92 has strong relationship with its’ composition and hot processing technology. Three types of P92 with different composition have been prepared. The relationship of delta ferrite between composition, smelting and heat forging process has been investigated for these three samples. The results show that the delta ferrite can be avoided by the adjustment of composition and making process, the delta ferrite will occurred in the matrix of P92 which without delta ferrite before heat treatment if the heat temperature exceed 1200°C , the delta ferrite existed in P92 ingot matrix resulted from the composition cannot be eliminated by hot working and heat treatment.

scholarly journals Non-Euclidean Biosymmetries and Algebraic Harmony in Genomes of Higher and Lower Organisms

2021 ◽  
Vol 248 ◽  
pp. 01010
Author(s):  
Sergey Petoukhov ◽  
Elena Petukhova ◽  
Vitaly Svirin
Keyword(s):  
Projective Geometry ◽  
Double Helix ◽  
Nucleotide Sequences ◽  
Cross Ratio ◽  
Harmonic Progression ◽  
The Cross ◽  
Dna Double Helix ◽  
Cooperative Organization ◽  
Relationship Of ◽  
The Relationship

The article is devoted to the study of the relationship of non-Euclidean symmetries in inherited biostructures with algebraic features of information nucleotide sequences in DNA molecules in the genomes of eukaryotes and prokaryotes. These genomic sequences obey the universal hyperbolic rules of the oligomer cooperative organization, which are associated with the harmonic progression 1/1, 1/2, 1/3,.., 1/n. The progression has long been known and studied in various branches of mathematics and physics. Now it has manifested itself in genetic informatics. The performed analysis of the harmonic progression revealed its connection with the cross-ratio, which is the main invariant of projective geometry. This connection consists in the fact that the magnitude of the cross-ratio is the same and is equal to 4/3 for any four adjacent members of this progression. The long DNA nucleotide sequences have fractal-like structure with so called epi-chains, whose structures are also related to the harmonic progression and the projective-geometrical symmetries. The received results are related additionally to a consideration of DNA double helix as helical antenna. This fact of the connection of genetic informatics with the main invariant of projective geometry can be used to explain the implementation of some non-Euclidean symmetries in genetically inherited structures of living bodies.

scholarly journals Comparative Biology of Centrosomal Structures in Eukaryotes

Cells ◽  
2018 ◽  
Vol 7 (11) ◽  
pp. 202
Author(s):  
Ralph Gräf
Keyword(s):  
Eukaryotic Cell ◽  
Spindle Pole ◽  
Comparative Biology ◽  
Special Issue ◽  
Microtubule Organization ◽  
Spindle Pole Bodies ◽  
History Of ◽  
Relationship Of ◽  
The Relationship

The centrosome is not only the largest and most sophisticated protein complex within a eukaryotic cell, in the light of evolution, it is also one of its most ancient organelles. This special issue of “Cells” features representatives of three main, structurally divergent centrosome types, i.e., centriole-containing centrosomes, yeast spindle pole bodies (SPBs), and amoebozoan nucleus-associated bodies (NABs). Here, I discuss their evolution and their key-functions in microtubule organization, mitosis, and cytokinesis. Furthermore, I provide a brief history of centrosome research and highlight recently emerged topics, such as the role of centrioles in ciliogenesis, the relationship of centrosomes and centriolar satellites, the integration of centrosomal structures into the nuclear envelope and the involvement of centrosomal components in non-centrosomal microtubule organization.

Zero-field splitting calculations. Part II. Tabulation of the reduced matrix elements of the irreducible double tensor operators

1976 ◽  
Vol 54 (12) ◽  
pp. 1228-1233 ◽  
Author(s):  
R. Chatterjee ◽  
M. R. Smith ◽  
H. A. Buckmaster
Keyword(s):  
The Other ◽  
Tensor Operator ◽  
Zero Field ◽  
Matrix Elements ◽  
Zero Field Splitting ◽  
Field Splitting ◽  
The Matrix ◽  
The Many ◽  
Relationship Of ◽  
The Relationship

The many-electron reduced matrix elements of the double tensor operator [Formula: see text] are tabulated for the pn, dn and fn configurations. These tables have been calculated from the Racah formalism and form an extension of the tabulations given by Nielson and Koster for K2 = 1. The relationship of this tensor with the other double tensors and the calculation of the matrix elements is summarized. See Chatterjee et al for an application.

Address of the President Dr E. D. Adrian, O. M., at the Anniversary Meeting, 1 December 1952

1953 ◽  
Vol 140 (901) ◽  
pp. 443-453
Keyword(s):  
Wave Theory ◽  
Physical World ◽  
Negative Energy ◽  
Wave Mechanics ◽  
First Order ◽  
The Matrix ◽  
Relationship Of ◽  
The Relationship ◽  
Made In

The Copley Medal is awarded to Professor Paul Adrien Maurice Dirac for is remarkable contributions to the quantum theory of elementary particles and ectromagnetic fields. All his work has a very distinctive quality, in that he has Shown how to make evident the relationship of the remote abstractions of the mathematician to the extremely practical problems facing the atomic Phyysicist. This appeared even in his earliest work, for in 1926 he took up the commutative algebra of Heisenberg, and solved the problem of a non- planetary orbit. Not long afterwards he showed how the ‘matrix’ of Heisenberg could be identified with the ‘wave mechanics’ of Schrödinger. It is this paper, with its development of the idea of ‘representations’ physical states, that more than any other has given the colour of his work. The advances made in 1927 had not provided a relativistically invariant for the electron, nor had they explained the phenomenon of ‘electron’. In 1928 he remedied both of these defects at the same time. Perhaps the quality of this work was that it replaced the second order of equations, universal in wave-theory, by equations of the first order. These equa- had some astonishing consequences, such as possible states of negative energy; and Dirac attempted a physical interpretation of these states by Le concept of a background of electrons occupying nearly all such states. An state appeared in the physical world to be a particle of electronic and positive charge, equal in magnitude to that of the electron. The ‘positive electron’ or ‘positron’ was actually only discovered several years later and it into Dirac’s scheme.

The Properties of an Intercellular Matrix and its Relation to Electrolytes

1926 ◽  
Vol 3 (3) ◽  
pp. 167-187
Author(s):  
J. GRAY
Keyword(s):  
Sodium Iodide ◽  
Negative Charge ◽  
Sea Water ◽  
Ion Concentration ◽  
Metallic Ions ◽  
Intercellular Matrix ◽  
Hydroxyl Ion ◽  
The Matrix ◽  
Relationship Of ◽  
The Relationship

1. The intercellular matrix of the cells on the gills of Mytilus edulis is readily dispersed by hydroxyl ions. 2. All cations inhibit the action of hydroxyl ions, but the divalent metals are much more powerful than the monovalent metals. All divalent metallic ions except magnesium irreversibly coagulate the matrix at the hydroxyl ion concentration of seawater. This does not occur in the presence of magnesium ions. 3. There is a marked difference between the action of different non-electrolytes, since in the absence of salts the matrix remains stable for a much longer period in sugar, or glycerine, than in urea. Alcohol in certain concentrations has a marked stabilising action in the absence of salts. 4. With pure solutions of different monovalent sodium salts the anions can be arranged in a well-marked series in which the matrix is most readily dispersed in sodium iodide I'< Br'. NO', < C1'< Ac'. 5. The relationship of the matrix to ions is similar to that between protein systems and ions, when attention is paid to both the electrostatic and lyophilic effect of the ions, and to the fact that the matrix is normally in equilibrium with a solution containing divalent metallic ions -- magnesium in particular. The analogy must, however, not be pushed too far. 6. The intercellular matrix of Mytilus cells can only possess a very slight electro-negative charge when in equilibrium with sea-water. If the constitution of the membrane is altered in such a way as to increase this charge, a type of matrix forms in which calcium is an essential constituent. Such a matrix appears to exist in echinoderms and in some other types.

scholarly journals Crystal Field Effects in S-state Ions Due to Exchange Polarization

1976 ◽  
Vol 29 (3) ◽  
pp. 177 ◽  
Author(s):  
DJ Newman
Keyword(s):  
Crystal Field ◽  
Electron Correlation ◽  
Ground State ◽  
Matrix Elements ◽  
Open Shells ◽  
The Matrix ◽  
New Type ◽  
Relationship Of ◽  
The Relationship ◽  
Exchange Polarization

It is shown that the matrix elements of the tensor operators describing a new type of crystal field can be calculated using the properties of the spin ~ quasi-spin transformation. The relationship of this field to electron correlation in open shells is clarified, and its contribution to the ground state splittings of S-state ions is discussed

scholarly journals Riemann-Hilbert Approach of The Complex Sharma-Tasso-Olver Equation and Its N-Soliton Solutions

2021 ◽  
Author(s):  
Sha Li ◽  
Tiecheng Xia ◽  
Jian Li
Keyword(s):  
Soliton Solution ◽  
Hilbert Problem ◽  
Three Dimensional ◽  
Soliton Solutions ◽  
Lax Pair ◽  
Integrable Equation ◽  
The Matrix ◽  
Relationship Of ◽  
Parameter Values ◽  
The Relationship

Abstract In this paper, we use Riemann-Hilbert method to study the N-soliton solutions of the complex Sharma-Tasso-Olver(cSTO) equation. And then, based on analyzing the spectral problem of the Lax pair, the matrix Riemann-Hilbert problem for this integrable equation can be constructed, the N-soliton solutions about this system are given explicitly under the relationship of scattering matrix. At last, under the condition that some specifific parameter values are given, the three-dimensional diagram of the 2-soliton solution and the trajectory of the soliton solution will be simulated.

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