The muscle M3 x-ray diffraction peak and sarcomere length: No evidence for disordered myosin heads out of actin overlap

X-ray diffraction studies of muscle have provided a wealth of information on muscle structure and physiology, and the meridian of the diffraction pattern is particularly informative. Reconditi et al. (2014. J. Physiol.https://doi.org/10.1113/jphysiol.2013.267849) performed superb experiments on changes to the M3 meridional peak as a function of sarcomere length (SL). They found that the M3 intensity dropped almost linearly as sarcomere length increased at least to about SL = 3.0 µm, and that it followed the same track as tension, pointing toward zero at the end of overlap at ∼3.6 µm. They concluded that, just as tension could only be generated by overlapped myosin heads, so ordered myosin heads contributing to the M3 intensity could only occur in the overlap region of the A-band, and that nonoverlapped heads must be highly disordered. Here we show that this conclusion is not consistent with x-ray diffraction theory; it would not explain their observations. We discuss one possible reason for the change in M3 intensity with increasing sarcomere length in terms of increasing axial misalignment of the myosin filaments that at longer sarcomere lengths is limited by the elastic stretching of the M-band and titin.

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Analysis of the Strain Profile in Thin Au/Ni Multilayers by X-Ray Diffraction

MRS Proceedings ◽

10.1557/proc-208-211 ◽

1990 ◽

Vol 208 ◽

Cited By ~ 1

Author(s):

J. Chaudhuri ◽

V. Gondhalekar ◽

A. F. Jankowski

Keyword(s):

Diffraction Pattern ◽

Diffraction Theory ◽

Metallic Multilayers ◽

X Ray Diffraction ◽

Strain Profile ◽

X Ray ◽

Depth Profiles

ABSTRACTA dynamical x-ray diffraction theory has been used to obtain microscopic strain profiles in thin Au/Ni multilayers. Depth profiles of strains in these multilayers, with repeat periodicities varying from 0.82 nm to 9.0 nm, are obtained by an iterative fitting of the calculated diffraction pattern with the experimental one. Interfacial coherency is found to play an important role in understanding the origin of the supermodulus effect in metallic multilayers.

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X-Ray Powder Diffraction Pattern for Reaction-HIPed A118Ti2Mg3

Powder Diffraction ◽

10.1017/s0885715600018765 ◽

1992 ◽

Vol 7 (4) ◽

pp. 223-225 ◽

Cited By ~ 4

Author(s):

Frank W. Gayle ◽

Francis S. Biancaniello ◽

Robert J. Schaefer ◽

Rodney D. Jiggets

Keyword(s):

Experimental Data ◽

Diffraction Pattern ◽

Powder Diffraction ◽

Hot Isostatic Pressing ◽

Diffraction Peak ◽

X Ray Diffraction ◽

Atomic Site ◽

X Ray ◽

Ideal Stoichiometry ◽

Good Agreement

AbstractThe cubic Al18Ti2Mg3 phase (184 atoms/unit cell, Z = 8, space group Fdm) has been fabricated by reaction hot isostatic pressing. Quantitative energy dispersive X-ray analysis showed the phase to have nearly ideal stoichiometry. Interplanar spacings and diffraction peak intensities have been determined by X-ray diffraction. The experimental data show good agreement with the pattern calculated using atomic site positional parameters for A118Cr2Mg3, confirming that A118Cr2Mg3 is the prototype for A118Ti2Mg3.

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Pd-Based Metallic Glass Films Formed by Electrodeposition Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.194.183 ◽

2012 ◽

Vol 194 ◽

pp. 183-186 ◽

Cited By ~ 2

Author(s):

Chihiro Mochizuki ◽

Takashi Senga ◽

Masami Shibata

Keyword(s):

Metallic Glass ◽

Diffraction Pattern ◽

Metallic Glasses ◽

Amorphous Structure ◽

Diffraction Peak ◽

Metallic Alloys ◽

X Ray Diffraction ◽

Electrodeposition Process ◽

X Ray ◽

Glass Films

The formation of Pd-Ni-P and Pd-Ni-Cu-P metallic glass films using the electrodeposition method was examined. In this study, the structure and composition of these metallic alloys were investigated at various condition of electrodeposition. The X-ray diffraction pattern on the electrodeposited Pd-Ni-P films in the range of 18-69 at% Pd, 12-62 at% Ni and 9-21 at% P showed a broad diffraction peak, which indicates metallic amorphous structure. A result of DSC showed that the electrodeposited Pd-Ni-P films in the range of 36-57 at% Pd, 24-47 at% Ni and 16-21 at% P were metallic glasses. In addition, it was proven that the electrodeposited Pd54Cu8Ni22P16 film was metallic glass.

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Electron Microscopy of Shock Loaded Polycrystalline Beryllium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052547 ◽

1974 ◽

Vol 32 ◽

pp. 506-507 ◽

Cited By ~ 1

Author(s):

J. M. Galbraith ◽

L. E. Murr ◽

A. L. Stevens

Keyword(s):

Electron Microscopy ◽

Wave Propagation ◽

Structural Change ◽

Single Crystal ◽

Diffraction Pattern ◽

Shock Loading ◽

Slip Systems ◽

Compression Tests ◽

X Ray Diffraction ◽

X Ray

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.

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Cytomembrane Preservation in Tissue Dehydrated Only With Glutaraldehyde and Epon 812 Resin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072046 ◽

1973 ◽

Vol 31 ◽

pp. 320-321

Author(s):

Daniel C. Pease

Keyword(s):

Diffraction Pattern ◽

X Ray Diffraction ◽

High Concentration ◽

Unpublished Study ◽

X Ray ◽

Sectioned Material

A previous study demonstrated that tissue could be successfully infiltrated with 50% glutaraldehyde, and then subsequently polymerized with urea to create an embedment which retained cytomembrane lipids in sectioned material. As a result, the 180-190 Å periodicity characteristic of fresh, mammalian myelin was preserved in sections, as was a brilliant birefringence, and the capacity to bind OsO4 vapor in the hydrophobic bilayers. An associated (unpublished) study, carried out in co-operation with Drs. C.K. Akers and D.F. Parsons, demonstrated that the high concentration of glutaraldehyde (and urea) did not significantly alter the X-ray diffraction pattern of aldehyde-fixed, myelin. Thus, by itself, 50% glutaraldehyde has little effect upon cytomembrane systems and can be used with confidence for the first stages of dehydration.

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X-ray diffraction properties of curved crystal diffractors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133308 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1734-1735

Author(s):

W. Z. Chang ◽

D. B. Wittry

Keyword(s):

Diffraction Theory ◽

X Rays ◽

Diffraction Image ◽

X Ray Diffraction ◽

Rocking Curve ◽

X Ray ◽

Bent Crystal ◽

Diffraction Geometry ◽

Crystal Parameter ◽

Quantitative Procedure

Since Du Mond and Kirkpatrick first discussed the principle of a bent crystal spectrograph in 1930, curved single crystals have been widely utilized as spectrometric monochromators as well as diffractors for focusing x rays diverging from a point. Curved crystal diffraction theory predicts that the diffraction parameters - the rocking curve width w, and the peak reflection coefficient r of curved crystals will certainly deviate from those of their flat form. Due to a lack of curved crystal parameter data in current literature and the need for optimizing the choice of diffraction geometry and crystal materials for various applications, we have continued the investigation of our technique presented at the last conference. In the present abstract, we describe a more rigorous and quantitative procedure for measuring the parameters of curved crystals.The diffraction image of a singly bent crystal under study can be obtained by using the Johann geometry with an x-ray point source.

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Highlights in the history of X-ray topography1

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1524/zkri.1995.210.6.394 ◽

1995 ◽

Vol 210 (6) ◽

Author(s):

A. R. Lang

Keyword(s):

Magnetic Domain ◽

Diffraction Theory ◽

Dislocation Loops ◽

X Ray Diffraction ◽

X Ray ◽

Domain Structures ◽

Structure Factors ◽

History Of ◽

Dislocation Sources ◽

Non Destructive

AbstractX-ray topography provides a non-destructive method of mapping point-by-point variations in orientation and reflecting power within crystals. The discovery, made by several workers independently, that in nearly perfect crystals it was possible to detect individual dislocations by X-ray diffraction contrast started an epoch of rapid exploitation of X-ray topography as a new, general method for assessing crystal perfection. Another discovery, that of X-ray Pendellösung, led to important theoretical developments in X-ray diffraction theory and to a new and precise method for measuring structure factors on an absolute scale. Other highlights picked out for mention are studies of Frank-Read dislocation sources, the discovery of long dislocation helices and lines of coaxial dislocation loops in aluminium, of internal magnetic domain structures in Fe-3 wt.% Si, and of stacking faults in silicon and natural diamonds.

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