scholarly journals On Special Spacelike Hybrid Numbers

Mathematics ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1671
Author(s):  
Anetta Szynal-Liana ◽  
Iwona Włoch

Hybrid numbers are generalizations of complex, hyperbolic and dual numbers. A hyperbolic complex structure is frequently used in both pure mathematics and numerous areas of physics. In this paper we introduce a special kind of spacelike hybrid number, namely the F(p,n)-Fibonacci hybrid numbers and we give some of their properties.

Author(s):  
Xinlin Huang ◽  
Jianmin Gao ◽  
Hongquan Jiang ◽  
Zhiyong Gao ◽  
Fumin Chen

Fault root causes tracing of complicated equipment in modern process industry is very important for accident and economic loss prevention. Due to the structure complexity of complicated equipment, failures happen from small parts and propagate through complex pathways often leading to serious system faults. These kind of faults caused by non-critical parts account for a large part of all the faults of complicated equipment and often cannot get enough attention in fault diagnosis. In order to trace the root causes of this kind of fault, the failure dependent relationship and fault propagation mode must be modeled accurately and effectively. Fault graph proposed by H. P. Alesso is a useful tool to represent complex structure and fault propagation pathway of complicated equipment with a special kind of fault-oriented directed graph expanded from fault tree. Fault graph takes advantage of graph rather than tree to describe complex relation between failure modes of components, and uses logic connectives to connect failure modes with logical relationship. Based on the basic concept of fault graph introduced by H. P. Alesso, this article focuses on the issues of fault graph constructing and fault graph fault root causes deducing. A fault graph constructing method was firstly discussed which uses the results of failure mode and effects analysis and the mathematical tool of polychromatic matrix and can be easily performed with the least manual work. Then the fault root causes deducing method of fault graph was investigated which focuses on fault graph reachability calculation and fault propagation pathway searching. The fault graph reachability calculation is put forward from doubletons to multiple root causes so that the reachabiltiy of any steps of fault graph pathway can be calculated. The fault propagation pathway searching method can be performed to reveal the detailed fault propagation pathway. A case study of fault graph modeling and fault root causes analysis based on fault graph of a certain type of centrifugal compressor which has complex internal structure is introduced. The case study shows that the proposed method is effective for fault root cause tracing of complicated equipment.


Author(s):  
Anetta Szynal-Liana ◽  
Iwona Włoch
Keyword(s):  

The hybrid numbers are generalization of complex, hyperbolic and dual numbers. In this paper we consider  a special kind of hybrid numbers, namely the Mersenne hybrid numbers and we give some of their properties.


1927 ◽  
Vol 1 (1) ◽  
pp. 39-40
Author(s):  
H. W. Richmond

If L, M, N denote Prof. Study's Dual Coordinates of a straight line (see Proc. Edinburgh Math. Soc., 44 (1926), 90–97), any (homogeneous) equation F (L, M, N) = 0 must define a certain system of lines. By the nature of dual numbers we must havewhere U and V are functions of l, m, n, λ, μ, ν, the ordinary (Pluckerian) coordinates. Since F = 0 implies U = 0 and V = 0 the system of lines is a congruence. But it is a congruence of a very special kind, whose nature will now be considered.


Author(s):  
V.V. Rybin ◽  
E.V. Voronina

Recently, it has become essential to develop a helpful method of the complete crystallographic identification of fine fragmented crystals. This was maainly due to the investigation into structural regularity of large plastic strains. The method should be practicable for determining crystallographic orientation (CO) of elastically stressed micro areas of the order of several micron fractions in size and filled with λ>1010 cm-2 density dislocations or stacking faults. The method must provide the misorientation vectors of the adjacent fragments when the angle ω changes from 0 to 180° with the accuracy of 0,3°. The problem is that the actual electron diffraction patterns obtained from fine fragmented crystals are the superpositions of reflections from various fragments, though more than one or two reflections from a fragment are hardly possible. Finally, the method should afford fully automatic computerized processing of the experimental results.The proposed method meets all the above requirements. It implies the construction for a certain base position of the crystal the orientation matrix (0M) A, which gives a single intercorrelation between the coordinates of the unity vector in the reference coordinate system (RCS) and those of the same vector in the crystal reciprocal lattice base : .


Author(s):  
W. Chiu ◽  
M.F. Schmid ◽  
T.-W. Jeng

Cryo-electron microscopy has been developed to the point where one can image thin protein crystals to 3.5 Å resolution. In our study of the crotoxin complex crystal, we can confirm this structural resolution from optical diffractograms of the low dose images. To retrieve high resolution phases from images, we have to include as many unit cells as possible in order to detect the weak signals in the Fourier transforms of the image. Hayward and Stroud proposed to superimpose multiple image areas by combining phase probability distribution functions for each reflection. The reliability of their phase determination was evaluated in terms of a crystallographic “figure of merit”. Grant and co-workers used a different procedure to enhance the signals from multiple image areas by vector summation of the complex structure factors in reciprocal space.


2019 ◽  
Vol 15 (S354) ◽  
pp. 189-194
Author(s):  
J. B. Climent ◽  
J. C. Guirado ◽  
R. Azulay ◽  
J. M. Marcaide

AbstractWe report the results of three VLBI observations of the pre-main-sequence star AB Doradus A at 8.4 GHz. With almost three years between consecutive observations, we found a complex structure at the expected position of this star for all epochs. Maps at epochs 2007 and 2010 show a double core-halo morphology while the 2013 map reveals three emission peaks with separations between 5 and 18 stellar radii. Furthermore, all maps show a clear variation of the source structure within the observing time. We consider a number of hypothesis in order to explain such observations, mainly: magnetic reconnection in loops on the polar cap, a more general loop scenario and a close companion to AB Dor A.


2020 ◽  
Vol 477 (1) ◽  
pp. 173-189 ◽  
Author(s):  
Marco Pedretti ◽  
Carolina Conter ◽  
Paola Dominici ◽  
Alessandra Astegno

Arabidopsis centrin 2, also known as calmodulin-like protein 19 (CML19), is a member of the EF-hand superfamily of calcium (Ca2+)-binding proteins. In addition to the notion that CML19 interacts with the nucleotide excision repair protein RAD4, CML19 was suggested to be a component of the transcription export complex 2 (TREX-2) by interacting with SAC3B. However, the molecular determinants of this interaction have remained largely unknown. Herein, we identified a CML19-binding site within the C-terminus of SAC3B and characterized the binding properties of the corresponding 26-residue peptide (SAC3Bp), which exhibits the hydrophobic triad centrin-binding motif in a reversed orientation (I8W4W1). Using a combination of spectroscopic and calorimetric experiments, we shed light on the SAC3Bp–CML19 complex structure in solution. We demonstrated that the peptide interacts not only with Ca2+-saturated CML19, but also with apo-CML19 to form a protein–peptide complex with a 1 : 1 stoichiometry. Both interactions involve hydrophobic and electrostatic contributions and include the burial of Trp residues of SAC3Bp. However, the peptide likely assumes different conformations upon binding to apo-CML19 or Ca2+-CML19. Importantly, the peptide dramatically increases the affinity for Ca2+ of CML19, especially of the C-lobe, suggesting that in vivo the protein would be Ca2+-saturated and bound to SAC3B even at resting Ca2+-levels. Our results, providing direct evidence that Arabidopsis SAC3B is a CML19 target and proposing that CML19 can bind to SAC3B through its C-lobe independent of a Ca2+ stimulus, support a functional role for these proteins in TREX-2 complex and mRNA export.


2019 ◽  
Vol 476 (21) ◽  
pp. 3227-3240 ◽  
Author(s):  
Shanshan Wang ◽  
Yanxiang Zhao ◽  
Long Yi ◽  
Minghe Shen ◽  
Chao Wang ◽  
...  

Trehalose-6-phosphate (T6P) synthase (Tps1) catalyzes the formation of T6P from UDP-glucose (UDPG) (or GDPG, etc.) and glucose-6-phosphate (G6P), and structural basis of this process has not been well studied. MoTps1 (Magnaporthe oryzae Tps1) plays a critical role in carbon and nitrogen metabolism, but its structural information is unknown. Here we present the crystal structures of MoTps1 apo, binary (with UDPG) and ternary (with UDPG/G6P or UDP/T6P) complexes. MoTps1 consists of two modified Rossmann-fold domains and a catalytic center in-between. Unlike Escherichia coli OtsA (EcOtsA, the Tps1 of E. coli), MoTps1 exists as a mixture of monomer, dimer, and oligomer in solution. Inter-chain salt bridges, which are not fully conserved in EcOtsA, play primary roles in MoTps1 oligomerization. Binding of UDPG by MoTps1 C-terminal domain modifies the substrate pocket of MoTps1. In the MoTps1 ternary complex structure, UDP and T6P, the products of UDPG and G6P, are detected, and substantial conformational rearrangements of N-terminal domain, including structural reshuffling (β3–β4 loop to α0 helix) and movement of a ‘shift region' towards the catalytic centre, are observed. These conformational changes render MoTps1 to a ‘closed' state compared with its ‘open' state in apo or UDPG complex structures. By solving the EcOtsA apo structure, we confirmed that similar ligand binding induced conformational changes also exist in EcOtsA, although no structural reshuffling involved. Based on our research and previous studies, we present a model for the catalytic process of Tps1. Our research provides novel information on MoTps1, Tps1 family, and structure-based antifungal drug design.


2010 ◽  
pp. 439-450
Author(s):  
Marta Janczewska

Research team of physicians and lab technicians under Izrael Milejkowski’s direction undertook the effort to carry out a series of clinical and biochemical experiments on patients dying of starvation in the Warsaw ghetto so as to receive the fullest possible picture of hunger disease. The research was carried out according to all the rigors of strict scientific discipline, and the authors during their work on academic articles, published it after the war entitled: „Starvation disease: hunger research carried out in the Warsaw ghetto in 1942,” according to their own words, they “supplemented the gap in accordance with the progress of knowledge.” The article is devoted to the reflections over ethical dilemmas of the research team, who were forced in their work to perform numerous medical treatments of experimental nature on extremely exhausted patients. The ill, according to Dr Fajgenblat’s words,“demonstrated negativism toward the research and treatment, which extremely hindered the work, and sometimes even frustrated it.” The article attempts to look at the monumental research work of the Warsaw ghetto doctors as a special kind of response of the medical profession to the feeling of helplessness to the dying patients. The article analyzes the situation of Warsaw ghetto doctors, who undertook the research without support of any outer authority, which could settle their possible ethical dilemmas (Polish deontological codes, European discussions on the conditions of the admissibility of medical research on patients, etc.).


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