scholarly journals A Lagrangian fibration of the isotropic 3-dimensional harmonic oscillator with monodromy

2019 ◽  
Vol 60 (3) ◽  
pp. 032103
Author(s):  
Irina Chiscop ◽  
Holger R. Dullin ◽  
Konstantinos Efstathiou ◽  
Holger Waalkens
Keyword(s):  
Harmonic Oscillator ◽  
3 Dimensional ◽  
Lagrangian Fibration

scholarly journals The 3-dimensional q-deformed harmonic oscillator and magic numbers of alkali metal clusters

1999 ◽  
Vol 302 (5-6) ◽  
pp. 392-398 ◽  
Author(s):  
Dennis Bonatsos ◽  
N. Karoussos ◽  
P.P. Raychev ◽  
R.P. Roussev ◽  
P.A. Terziev
Keyword(s):  
Alkali Metal ◽  
Harmonic Oscillator ◽  
Metal Clusters ◽  
Magic Numbers ◽  
3 Dimensional ◽  
Alkali Metal Clusters

scholarly journals QUENCHING OF THE DEUTERON IN FLIGHT

2007 ◽  
Vol 16 (01) ◽  
pp. 69-80
Author(s):  
M. DILLIG ◽  
C. ROTHLEITNER
Keyword(s):  
Harmonic Oscillator ◽  
Momentum Spectrum ◽  
High Momentum ◽  
Significant Modification ◽  
Oscillator Potential ◽  
Harmonic Oscillator Potential ◽  
Potential Equation ◽  
Lorentz Contraction ◽  
3 Dimensional ◽  
Analytical Result

We investigate the Lorentz contraction of a deuteron in flight. Starting from the Blankenbecler-Sugar projection of the Bethe-Salpeter equation to a 3-dimensional quasi potential equation, we apply it for the deuteron bound in an harmonic oscillator potential (for an analytical result) or by the Bonn NN potential for a more realistic estimate. We find substantial quenching with increasing external momenta and a significant modification of the high momentum spectrum of the deuteron.

Thermodynamical dimensional reduction in a UV & IR-deformed Snyder space

2017 ◽  
Vol 26 (11) ◽  
pp. 1750126
Author(s):  
Kourosh Nozari ◽  
Hamed Ramezani
Keyword(s):  
Harmonic Oscillator ◽  
Dimensional Reduction ◽  
Degrees Of Freedom ◽  
Length Scale ◽  
3 Dimensional ◽  
Six Degrees Of Freedom ◽  
Thermodynamical Properties ◽  
Equipartition Theorem ◽  
Oscillator Length ◽  
Set Up

We study a formulation of statistical mechanics in the context of symplectic structures of the IR and also UV & IR-deformed Snyder phase-spaces. We derive the corresponding invariant Liouville volume and by using it we obtain the deformed partition function. We then study the thermodynamical properties of the 3-dimensional harmonic oscillator in this set-up. By using the equipartition theorem, we show that two of the six degrees of freedom for a 3-dimensional harmonic oscillator will be frozen as the temperature increases. Also, at a constant temperature, whatever is the increase in oscillator length, this reduction of the number of degrees of freedom gets more and more appreciable and it offers an effective dimensional reduction of space from [Formula: see text] to [Formula: see text] when it is close to the IR-length scale.

scholarly journals The 3-Dimensional g-Deformed Harmonic Oscillator and a Unified Description of Magic Numbers of Metal Clusters

2019 ◽  
Vol 10 ◽  
pp. 215
Author(s):  
N. Karoussos ◽  
Dennis Bonatsos ◽  
P. P. Raychev ◽  
R. P. Roussev
Keyword(s):  
Harmonic Oscillator ◽  
Noble Metals ◽  
Alkali Metals ◽  
Metal Clusters ◽  
Magic Numbers ◽  
Divalent Metals ◽  
3 Dimensional ◽  
Theoretical Predictions ◽  
Alkali Metal Clusters ◽  
Trivalent Metals

Magic numbers predicted by a 3-dimensional (/-deformed harmonic oscillator with u9(3) D soq(3) symmetry are compared to experimental data for atomic clusters of alkali metals (Li, Na, K, Rb, Cs), noble metals (Cu, Ag, Au), divalent metals (Zn, Cd), and trivalent metals (Al, In), as well as to theoretical predictions of jellium models, Woods-Saxon and wine bottle potentials, and to the classification scheme using the 3n + / pseudo quantum number. In alkali metal clusters and noble metal clusters the 3-dimensional çr-deformed harmonic oscillator correctly predicts all experimentally observed magic numbers up to 1500 (which is the expected limit of validity for theories based on the filling of electronic shells), while in addition it gives satisfactory results for the magic numbers of clusters of divalent metals and trivalent metals, thus indicating that ug(3), which is a nonlinear extension of the u(3) symmetry of the spherical (3-dimensional isotropic) harmonic oscillator, is a good candidate for being the symmetry of systems of several metal clusters.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Structural preservation and absolute contrast of catalase crystal sections prepared with tannic acid

1983 ◽  
Vol 41 ◽  
pp. 448-449
Author(s):  
C.W. Akey ◽  
M. Szalay ◽  
S.J. Edelstein
Keyword(s):  
Tannic Acid ◽  
Beef Heart ◽  
X Rays ◽  
Screw Axis ◽  
General Applicability ◽  
Thin Sections ◽  
Beef Liver ◽  
3 Dimensional ◽  
Dimensional Reconstruction ◽  
Structural Preservation

Three methods of obtaining 20 Å resolution in sectioned protein crystals have recently been described. They include tannic acid fixation, low temperature embedding and grid sectioning. To be useful for 3-dimensional reconstruction thin sections must possess suitable resolution, structural fidelity and a known contrast. Tannic acid fixation appears to satisfy the above criteria based on studies of crystals of Pseudomonas cytochrome oxidase, orthorhombic beef liver catalase and beef heart F1-ATPase. In order to develop methods with general applicability, we have concentrated our efforts on a trigonal modification of catalase which routinely demonstrated a resolution of 40 Å. The catalase system is particularly useful since a comparison with the structure recently solved with x-rays will permit evaluation of the accuracy of 3-D reconstructions of sectioned crystals.Initially, we re-evaluated the packing of trigonal catalase crystals studied by Longley. Images of the (001) plane are of particular interest since they give a projection down the 31-screw axis in space group P3121. Images obtained by the method of Longley or by tannic acid fixation are negatively contrasted since control experiments with orthorhombic catalase plates yield negatively stained specimens with conditions used for the larger trigonal crystals.

Deviations from Ideal Decagonal Symmetry in Electron Diffraction Patterns of the “Decagonal” Phase in the Al-Co-Cu Alloy System

1991 ◽  
Vol 49 ◽  
pp. 914-915
Author(s):  
Atul S. Ramani ◽  
Earle R. Ryba ◽  
Paul R. Howell
Keyword(s):  
Electron Microscope ◽  
Alloy System ◽  
Nominal Composition ◽  
Dimensional Lattice ◽  
3 Dimensional ◽  
Decagonal Phase ◽  
Cu Alloy ◽  
Transmission Electron ◽  
Lattice Periodicity ◽  
Diffraction Patterns

The “decagonal” phase in the Al-Co-Cu system of nominal composition Al65CO15Cu20 first discovered by He et al. is especially suitable as a topic of investigation since it has been claimed that it is thermodynamically stable and is reported to be periodic in the dimension perpendicular to the plane of quasiperiodic 10-fold symmetry. It can thus be expected that it is an important link between fully periodic and fully quasiperiodic phases. In the present paper, we report important findings of our transmission electron microscope (TEM) study that concern deviations from ideal decagonal symmetry of selected area diffraction patterns (SADPs) obtained from several “decagonal” phase crystals and also observation of a lattice of main reflections on the 10-fold and 2-fold SADPs that implies complete 3-dimensional lattice periodicity and the fundamentally incommensurate nature of the “decagonal” phase. We also present diffraction evidence for a new transition phase that can be classified as being one-dimensionally quasiperiodic if the lattice of main reflections is ignored.

A Novel Reconstitution Method for Inducing the Formation of Regular 2-Dimensional Arrays of Membrane Proteins and Lipids

1988 ◽  
Vol 46 ◽  
pp. 152-153 ◽  
Author(s):  
A. Engel ◽  
A. Holzenburg ◽  
K. Stauffer ◽  
J. Rosenbusch ◽  
U. Aebi
Keyword(s):  
Membrane Proteins ◽  
Flow Rate ◽  
Lipid Membranes ◽  
Functional Characterization ◽  
Dimensional Structure ◽  
Electron Crystallography ◽  
Peltier Element ◽  
Protein Ratio ◽  
Precise Control ◽  
3 Dimensional

Reconstitution of solubilized and purified membrane proteins in the presence of phospholipids into vesicles allows their functions to be studied by simple bulk measurements (e.g. diffusion of differently sized solutes) or by conductance measurements after transformation into planar membranes. On the other hand, reconstitution into regular protein-lipid arrays, usually forming at a specific lipid-to-protein ratio, provides the basis for determining the 3-dimensional structure of membrane proteins employing the tools of electron crystallography.To refine reconstitution conditions for reproducibly inducing formation of large and highly ordered protein-lipid membranes that are suitable for both electron crystallography and patch clamping experiments aimed at their functional characterization, we built a flow-dialysis device that allows precise control of temperature and flow-rate (Fig. 1). The flow rate is generated by a peristaltic pump and can be adjusted from 1 to 500 ml/h. The dialysis buffer is brought to a preselected temperature during its travel through a meandering path before it enters the dialysis reservoir. A Z-80 based computer controls a Peltier element allowing the temperature profile to be programmed as function of time.

Structure and Interaction of Protamine by Dark Field Electron Microscopy

1976 ◽  
Vol 34 ◽  
pp. 160-161
Author(s):  
D.P. Bazett-Jones ◽  
F.P. Ottensmeyer
Keyword(s):  
Electron Microscopy ◽  
Dark Field ◽  
Amino Acid Sequences ◽  
Dimensional Structure ◽  
3 Dimensional ◽  
Field Electron ◽  
Proposed Model ◽  
Field Electron Microscopy ◽  
Dark Field Electron ◽  
Positively Charged

It has been shown for some time that it is possible to obtain images of small unstained proteins, with a resolution of approximately 5Å using dark field electron microscopy (1,2). Applying this technique, we have observed a uniformity in size and shape of the 2-dimensional images of pure specimens of fish protamines (salmon, herring (clupeine, Y-l) and rainbow trout (Salmo irideus)). On the basis of these images, a model for the 3-dimensional structure of the fish protamines has been proposed (2).The known amino acid sequences of fish protamines show stretches of positively charged arginines, separated by regions of neutral amino acids (3). The proposed model for protamine structure (2) consists of an irregular, right-handed helix with the segments of adjacent arginines forming the loops of the coil.

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