Miscellaneous results: Ring structure, generators, relation to the inertia group

Recent work has drawn attention to the possibilities that small angle electron scattering offers as a source of information about the micro-structure of vacuum condensed films. In particular, this serves as a good detector of discontinuities within the films. A review of a kinematical theory describing the small angle scattering from a thin film composed of discrete particles packed close together will be presented. Such a model could be represented by a set of cylinders packed side by side in a two dimensional fluid-like array, the axis of the cylinders being normal to the film and the length of the cylinders becoming the thickness of the film. The Fourier transform of such an array can be regarded as a ring structure around the central beam in the plane of the film with the usual thickness transform in a direction normal to the film. The intensity profile across the ring structure is related to the radial distribution function of the spacing between cylinders.

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Immunoelectron microscope detection of C-type natriuretic peptide in normal human atrial tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100147776 ◽

1993 ◽

Vol 51 ◽

pp. 388-389

Author(s):

Chi-Ming Wei ◽

Margaret Hukee ◽

Christopher G.A. McGregor ◽

John C. Burnett

Keyword(s):

Amino Acid ◽

Natriuretic Peptide ◽

Vascular Tone ◽

Cardiac Tissue ◽

Ring Structure ◽

Terminal Amino Acid ◽

Amino Acid Peptide ◽

Normal Human ◽

Terminal Amino ◽

The Brain

C-type natriuretic peptide (CNP) is a newly identified peptide that is structurally related to atrial (ANP) and brain natriuretic peptide (BNP). CNP exists as a 22-amino acid peptide and like ANP and BNP has a 17-amino acid ring formed by a disulfide bond. Unlike these two previously identified cardiac peptides, CNP lacks the COOH-terminal amino acid extension from the ring structure. ANP, BNP and CNP decrease cardiac preload, but unlike ANP and BNP, CNP is not natriuretic. While ANP and BNP have been localized to the heart, recent investigations have failed to detect CNP mRNA in the myocardium although small concentrations of CNP are detectable in the porcine myocardium. While originally localized to the brain, recent investigations have localized CNP to endothelial cells consistent with a paracrine role for CNP in the control of vascular tone. While CNP has been detected in cardiac tissue by radioimmunoassay, no studies have demonstrated CNP localization in normal human heart by immunoelectron microscopy.

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Chow Rings, Decomposition of the Diagonal, and the Topology of Families (AM-187)

10.23943/princeton/9780691160504.001.0001 ◽

2017 ◽

Author(s):

Claire Voisin

Keyword(s):

Recent Work ◽

Chow Groups ◽

Ring Structure ◽

Complete Intersections ◽

Algebraic Varieties ◽

Chow Ring ◽

Hodge Structures ◽

Chow Rings ◽

Geometric Methods ◽

The Right

This book provides an introduction to algebraic cycles on complex algebraic varieties, to the major conjectures relating them to cohomology, and even more precisely to Hodge structures on cohomology. The book is intended for both students and researchers, and not only presents a survey of the geometric methods developed in the last thirty years to understand the famous Bloch-Beilinson conjectures, but also examines recent work by the author. It focuses on two central objects: the diagonal of a variety—and the partial Bloch-Srinivas type decompositions it may have depending on the size of Chow groups—as well as its small diagonal, which is the right object to consider in order to understand the ring structure on Chow groups and cohomology. An exploration of a sampling of recent works by the author looks at the relation, conjectured in general by Bloch and Beilinson, between the coniveau of general complete intersections and their Chow groups and a very particular property satisfied by the Chow ring of K3 surfaces and conjecturally by hyper-Kähler manifolds. In particular, the book delves into arguments originating in Nori's work that have been further developed by others.

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A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

10.26434/chemrxiv.11320130.v1 ◽

2019 ◽

Cited By ~ 2

Author(s):

Tian Lu ◽

Qinxue Chen ◽

Zeyu Liu

Keyword(s):

Molecular Dynamics ◽

Excited States ◽

Electronic Excitation ◽

Ring Structure ◽

Molecular Properties ◽

Molecular Vibration ◽

Full Characterization ◽

Long Time ◽

Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., Science, 365, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

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A Thorough Theoretical Exploration of Intriguing Characteristics of Cyclo[18]carbon: Geometry, Bonding Nature, Aromaticity, Weak Interaction, Reactivity, Excited States, Vibrations, Molecular Dynamics and Various Molecular Properties

10.26434/chemrxiv.11320130 ◽

2019 ◽

Cited By ~ 2

Author(s):

Tian Lu ◽

Qinxue Chen ◽

Zeyu Liu

Keyword(s):

Molecular Dynamics ◽

Excited States ◽

Electronic Excitation ◽

Ring Structure ◽

Molecular Properties ◽

Molecular Vibration ◽

Full Characterization ◽

Long Time ◽

Almost All

Although cyclo[18]carbon has been theoretically and experimentally investigated since long time ago, only very recently it was prepared and directly observed by means of STM/AFM in condensed phase (Kaiser et al., Science, 365, 1299 (2019)). The unique ring structure and dual 18-center π delocalization feature bring a variety of unusual characteristics and properties to the cyclo[18]carbon, which are quite worth to be explored. In this work, we present an extremely comprehensive and detailed investigation on almost all aspects of the cyclo[18]carbon, including (1) Geometric characteristics (2) Bonding nature (3) Electron delocalization and aromaticity (4) Intermolecular interaction (5) Reactivity (6) Electronic excitation and UV/Vis spectrum (7) Molecular vibration and IR/Raman spectrum (8) Molecular dynamics (9) Response to external field (10) Electron ionization, affinity and accompanied process (11) Various molecular properties. We believe that our full characterization of the cyclo[18]carbon will greatly deepen researchers' understanding of this system, and thereby help them to utilize it in practice and design its various valuable derivatives.

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The Concentric Structure of the Wisdom Poem in Job 28

Journal of Ancient Judaism ◽

10.30965/21967954-00901003 ◽

2018 ◽

Vol 9 (1) ◽

pp. 26-45

Author(s):

Ruth Henderson

Keyword(s):

Ring Structure ◽

Central Unit ◽

Central Section ◽

Book Of Job ◽

Rhetorical Question ◽

Linear Fashion ◽

Creative Power ◽

Concentric Pattern ◽

Human Effort ◽

Concentric Structure

The enigmatic wisdom poem of Job 28:1–28 stands apart from the rest of the book of Job in style and structure. Most read this poem in linear progression as three strophes (vv. 1–11; 15–19; 23–28) with an intervening refrain (vv. 12–14; 20–22). In this study, it is suggested that the poem has been presented in the form of a concentric or compositional ring structure, which juxtaposes arguments rather than presenting them in a linear fashion. According to this structure there are five compositional units, the centre of which holds the main point of the text (A, B, C, B1, A1). A central section (C vv. 15–19), maintains the traditional view of the supreme value of wisdom. The central unit is surrounded by two inner parallel sections each beginning with a rhetorical question concerning the location of wisdom (Sections B vv. 12–14 and B1 vv. 20–22), and two outer sections (A vv. 1–11 and A1 vv. 23–28) in which two contrasting ways of acquiring wisdom are presented: by independent human effort presented in the form of a mining metaphor (A vv. 1–11); or by contemplation of God’s omnipotent creative power and reverence for Him resulting in right behaviour (A1). Each of the major units also follows a concentric pattern.

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Genetic Nature of Mineralization on Native and Intermetalic Compounds in the Bobruisk Ring Structure (Republic of Belarus)

Доклады Академии наук ◽

10.31857/s086956520001198-0 ◽

2018 ◽

Vol 481 (2) ◽

pp. 174-178

Author(s):

V. Levitskiy ◽

◽

I. Levitskiy ◽

L. Pavlova ◽

V. Solodilova ◽

...

Keyword(s):

Ring Structure ◽

Genetic Nature

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Construction the A-B bicyclic ring structure of Stemocurtisisne

Letters in Organic Chemistry ◽

10.2174/1570178617666200207105649 ◽

2020 ◽

Vol 17 ◽

Author(s):

Duc Dau Xuan

Keyword(s):

Glutamic Acid ◽

Natural Product ◽

Mannich Reaction ◽

Boronic Acid ◽

Ring Opening ◽

Ring Structure ◽

Starting Material ◽

Epoxide Ring ◽

Epoxide Ring Opening

: The synthesis of the A-B bicyclic ring structure 3 of the natural product Stemocurtisine is described. The synthesis was accomplished in seven synthetic steps from commercially available L-glutamic acid. The key step involved a borono-Mannich reaction between the hemiaminal 6 and trans-β-styryl boronic acid and trans-β-styrylpotassiumtrifluoroborate to prepare the cis diene 4. Attempts to prepare the A-B-C ring compound 2 via intramolecular epoxide ring opening followed by rearangement under different basic conditions were unsuccessful. Only unreactive starting material was recovered.

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