scholarly journals Radiation damage studies in cardiac muscle cells and tissue using microfocused X-ray beams: experiment and simulation

2019 ◽  
Vol 26 (4) ◽  
pp. 980-990 ◽  
Author(s):  
Jan-David Nicolas ◽  
Sebastian Aeffner ◽  
Tim Salditt
Keyword(s):  
Cardiac Muscle ◽  
Radiation Damage ◽  
Muscle Cells ◽  
Soft Materials ◽  
X Ray Diffraction ◽  
Cardiac Muscle Cells ◽  
X Ray ◽  
Experimental Parameters ◽  
Radiation Resistant ◽  
The Impact

Soft materials are easily affected by radiation damage from intense, focused synchrotron beams, often limiting the use of scanning diffraction experiments to radiation-resistant samples. To minimize radiation damage in experiments on soft tissue and thus to improve data quality, radiation damage needs to be studied as a function of the experimental parameters. Here, the impact of radiation damage in scanning X-ray diffraction experiments on hydrated cardiac muscle cells and tissue is investigated. It is shown how the small-angle diffraction signal is affected by radiation damage upon variation of scan parameters and dose. The experimental study was complemented by simulations of dose distributions for microfocused X-ray beams in soft muscle tissue. As a simulation tool, the Monte Carlo software package EGSnrc was used that is widely used in radiation dosimetry research. Simulations also give additional guidance for a more careful planning of dose distribution in tissue.

X-Ray Diffraction Comparison of Radiation Damage in Rubber

1961 ◽  
Vol 34 (1) ◽  
pp. 250-264 ◽  
Author(s):  
W. E. Shelberg ◽  
L. H. Gevantman
Keyword(s):  
Radiation Damage ◽  
Radiation Resistance ◽  
Inert Atmosphere ◽  
Nuclear Radiation ◽  
Diffraction Spot ◽  
X Ray Diffraction ◽  
X Ray ◽  
Radiation Fields ◽  
Radiation Resistant ◽  
Mechanical Devices

Abstract This paper describes the use of an x-ray diffraction technique to correlate rubber radiation damage with rubber composition. Correlations between radiation damage and composition are useful as guides for the development of superior radiation resistant elastomers to be used as components of mechanical devices installed in high nuclear radiation fields. Rubber which is stretched and irradiated in an inert atmosphere is readily damaged by chain cleavage, manifested by loss of crystallinity, possible thinning, decreased x-ray diffraction intensities and eventual rupture (Figure 1). Loss of diffraction spot intensity was used to measure radiation damage in stretched rubber, and was tantamount to loss of crystallinity with little specimen thinning until just before rupture. Crystalline longevity was determined fur an irradiated “standard” rubber under standardized conditions and for other rubbers which were similar to the standard except for an added or substituted ingredient. A greater crystalline longevity connoted a greater radiation resistance, and the standard was used as 3 basis for comparing radiation resistance and composition.

THE EFFECTS OF ACUPUNCTURE ON CARDIAC MUSCLE CELLS AND BLOOD PRESSURE IN SPONTANEOUS HYPERTENSIVE RATS

2004 ◽  
Vol 29 (1) ◽  
pp. 83-95 ◽  
Author(s):  
Hung-Chien Wu ◽  
Jaung-Geng Lin ◽  
Chun-Hsien Chu ◽  
Yung-Hsien Chang ◽  
Chung-Gwo Chang ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Cardiac Muscle ◽  
Muscle Cells ◽  
Hypertensive Rats ◽  
Cardiac Muscle Cells

scholarly journals The impact of point defects in n-type GaN layers on thermal decomposition of InGaN/GaN QWs

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mikolaj Grabowski ◽  
Ewa Grzanka ◽  
Szymon Grzanka ◽  
Artur Lachowski ◽  
Julita Smalc-Koziorowska ◽  
...  
Keyword(s):  
Quantum Wells ◽  
High Temperatures ◽  
Point Defects ◽  
X Ray Diffraction ◽  
Helium Ions ◽  
X Ray ◽  
Sapphire Substrates ◽  
Transmission Electron ◽  
The Impact ◽  
Ingan Quantum Wells

AbstractThe aim of this paper is to give an experimental evidence that point defects (most probably gallium vacancies) induce decomposition of InGaN quantum wells (QWs) at high temperatures. In the experiment performed, we implanted GaN:Si/sapphire substrates with helium ions in order to introduce a high density of point defects. Then, we grew InGaN QWs on such substrates at temperature of 730 °C, what caused elimination of most (but not all) of the implantation-induced point defects expanding the crystal lattice. The InGaN QWs were almost identical to those grown on unimplanted GaN substrates. In the next step of the experiment, we annealed samples grown on unimplanted and implanted GaN at temperatures of 900 °C, 920 °C and 940 °C for half an hour. The samples were examined using Photoluminescence, X-ray Diffraction and Transmission Electron Microscopy. We found out that the decomposition of InGaN QWs started at lower temperatures for the samples grown on the implanted GaN substrates what provides a strong experimental support that point defects play important role in InGaN decomposition at high temperatures.

Dendroaspis Natriuretic Peptide Induces the Apoptosis of Cardiac Muscle Cells

2005 ◽  
Vol 27 (1) ◽  
pp. 33-51 ◽  
Author(s):  
Ki-Chan Ha ◽  
Han-Jung Chae ◽  
Cheng-Shi Piao ◽  
Suhn-Hee Kim ◽  
Hyung-Ryong Kim ◽  
...  
Keyword(s):  
Cardiac Muscle ◽  
Natriuretic Peptide ◽  
Muscle Cells ◽  
Cardiac Muscle Cells

Microwave Radiation Effects on Cardiac Muscle Cells in Vitro

1981 ◽  
Vol 86 (2) ◽  
pp. 358 ◽  
Author(s):  
M. J. Galvin ◽  
C. A. Hall ◽  
D. I. McRee
Keyword(s):  
Cardiac Muscle ◽  
Microwave Radiation ◽  
Radiation Effects ◽  
Muscle Cells ◽  
Cardiac Muscle Cells

scholarly journals Chirality, Gelation Ability and Crystal Structure: Together or Apart? Alkyl Phenyl Ethers of Glycerol as Simple LMWGs

Symmetry ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 732
Author(s):  
Alexander A. Bredikhin ◽  
Aidar T. Gubaidullin ◽  
Zemfira A. Bredikhina ◽  
Robert R. Fayzullin ◽  
Olga A. Lodochnikova
Keyword(s):  
Self Assembly ◽  
Chiral Recognition ◽  
Soft Materials ◽  
Gelling Agent ◽  
Low Molecular Weight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Types ◽  
Low Molecular Weight Gelators ◽  
Phenyl Ethers

Chiral recognition plays an important role in the self-assembly of soft materials, in particular supramolecular organogels formed by low molecular weight gelators (LMWGs). Out of 14 pairs of the studied racemic and enantiopure samples of alkyl-substituted phenyl ethers of glycerol, only eight enantiopure diols form the stable gels in nonane. The formation of gels from solutions was studied by polarimetry, and their degradation with the formation of xerogels was studied by the PXRD method. The revealed crystalline characteristics of all studied xerogels corresponded to those for crystalline samples of the parent gelators. In addition to those previously investigated, crystalline samples of enantiopure para-n-alkylphenyl glycerol ethers [alkyl = pentyl (5), hexyl (6), heptyl (7), octyl (8), nonyl (9)] and racemic 3-(3,5-dimethylphenoxy)propane-1,2-diol (rac-14) have been examined by single crystal X-ray diffraction analysis. Among 22 samples of compounds 1-14 studied by SC-XRD, seven different types of supramolecular motifs are identified, of which only two are realized in crystals of supramolecular gelators. An attempt was made to relate the ability to gel formation with the characteristics of the supramolecular motif of a potential gelling agent, and the frequency of formation of the motif, required for gelation, with the chiral characteristics of the sample.

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