scholarly journals X-ray induced Sm-ion valence conversion in Sm-ion implanted fluoroaluminate glasses towards high-dose radiation measurement

2019 ◽  
Vol 30 (18) ◽  
pp. 16740-16746 ◽  
Author(s):  
Farley Chicilo ◽  
Cyril Koughia ◽  
Richard Curry ◽  
Russel Gwilliam ◽  
Ruben Ahumada-Lazo ◽  
...  
Keyword(s):  
High Dose ◽  
Radiation Measurement ◽  
X Ray ◽  
Dose Radiation ◽  
Ion Implanted

High-Stable X-ray Imaging from All-Inorganic Perovskite Nanocrystals under a High Dose Radiation

2020 ◽  
Vol 11 (21) ◽  
pp. 9203-9209 ◽  
Author(s):  
Liuli Yang ◽  
Hao Zhang ◽  
Min Zhou ◽  
Lei Zhao ◽  
Weiqing Chen ◽  
...  
Keyword(s):  
High Dose ◽  
Inorganic Perovskite ◽  
Perovskite Nanocrystals ◽  
X Ray ◽  
X Ray Imaging ◽  
Dose Radiation

scholarly journals Extracellular vesicles released from irradiated neonatal mouse cheek tissue increased cell survival after radiation

2020 ◽  
Vol 62 (1) ◽  
pp. 73-78
Author(s):  
Kentaro Ariyoshi ◽  
Yota Hiroyama ◽  
Naoya Fujiwara ◽  
Tomisato Miura ◽  
Kosuke Kasai ◽  
...  
Keyword(s):  
Hair Follicle ◽  
Fibroblast Cell ◽  
Mouse Fibroblast ◽  
High Dose ◽  
Protective Effects ◽  
X Ray ◽  
Secreted Factors ◽  
The Common ◽  
Dose Radiation ◽  
Fibroblast Cell Lines

Abstract Alopecia is one of the common symptoms after high-dose radiation exposure. In our experiments, neonatal mice that received 7 Gy X-ray exhibited defects in overall hair growth, except for their cheeks. This phenomenon might suggest that some substances were secreted and prevented hair follicle loss in the infant tissues around their cheeks after radiation damage. In this study, we focused on exosome-like vesicles (ELV) secreted from cheek skin tissues and back skin tissues, as control, and examined their radiation protective effects on mouse fibroblast cell lines. We observed that ELV from irradiated cheek skin showed protective effects from radiation. Our results suggest that ELV from radiation-exposed cheek skin tissue is one of the secreted factors that prevent hair follicle loss after high-dose radiation.

Amorphization of Crystalline Phase Change Material by Ion Implantation

2010 ◽  
Vol 1251 ◽  
Author(s):  
Simone Raoux ◽  
Guy Cohen ◽  
Robert M. Shelby ◽  
Huai-Yu Cheng ◽  
Jean L Jordan-Sweet
Keyword(s):  
Ion Implantation ◽  
Phase Change ◽  
Phase Change Material ◽  
Crystalline Phase ◽  
High Dose ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Change Material ◽  
Ion Implanted

AbstractGermanium ion implantation at an energy of 30 keV was used as a different method to re-amorphize thin films of crystalline phase change material Ge2Sb2Te5 (GST). It was found that rather low doses of 5×1013 cm-2 were sufficient to re-amorphize GST. Amorphization was determined by X-ray diffraction (XRD) as well as reflectivity measurements. Re-crystallization characteristics of ion-implantation-amorphized samples was studied using time-resolved XRD. It showed that samples re-crystallize at an increased crystallization temperature with increasing dose compared to as-deposited material. A static laser tester was applied to measure the crystallization times of material that was (1) as–deposited amorphous; (2) crystallized by annealing and re-amorphized by melt-quenching using a laser pulse; and (3) crystallized by annealing and re-amorphized by ion implantation. It was found that as-deposited amorphous and high-dose ion implanted samples had longer crystallization times while melt-quenched amorphous and low-dose ion implanted samples had shorter crystallization times.

scholarly journals X-ray diffraction analysis of KY3F10 nanoparticles doped with Nd and preliminary studies for its use in high-dose radiation dosimetry

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Rodrigo Uchida Ichikawa ◽  
Horacio Marconi da Silva Matias Dantas Linhares ◽  
Andre Santos Barros Silva ◽  
Maria Ines Teixeira ◽  
Izilda Marcia Ranieri ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
Crystallite Size ◽  
Atomic Displacement ◽  
High Dose ◽  
X Ray Diffraction ◽  
Response Curves ◽  
X Ray ◽  
Cell Parameters ◽  
Structure And Microstructure ◽  
Dose Radiation

In this work, the structure and microstructure of Nd:KY3F10 nanoparticles was probed using X-ray synchrotron diffraction analysis. Rietveld refinement was applied to obtain cell parameters, atomic positions and atomic displacement factors to be compared with the ones found in literature. X-ray line profile methods were applied to determine mean crystallite size and crystallite size distribution. Thermoluminescent (TL) emission curves were measured for different radiation doses, from 0.10 kGy up to 10.0 kGy. Dose-response curves were obtained by area integration beneath the peaks from TL. The reproducibility of the results in this work has shown that this material can be considered a good dosimetric material.

Reconstruction of Chitin-Protein Complexes Using Correlation Averaging Methods: Ovipositor of the Ichneumon Fly Megarhyssa

1980 ◽  
Vol 38 ◽  
pp. 38-39
Author(s):  
L. T. Germinario ◽  
J. Blackwell ◽  
J. Frank
Keyword(s):  
Protein Complexes ◽  
Hexagonal Lattice ◽  
Uranyl Acetate ◽  
Optical Diffraction ◽  
Insect Cuticle ◽  
High Dose ◽  
Wide Angle ◽  
X Ray ◽  
Averaging Methods ◽  
Digital Correlation

This report describes the use of digital correlation and averaging methods 1,2 for the reconstruction of high dose electron micrographs of the chitin-protein complex from Megarhyssa ovipositor. Electron microscopy of uranyl acetate stained insect cuticle has demonstrated a hexagonal array of unstained chitin monofibrils, 2.4−3.0 nm in diameter, in a stained protein matrix3,4. Optical diffraction Indicated a hexagonal lattice with a = 5.1-8.3 nm3 A particularly well ordered complex is found in the ovipositor of the ichneumon fly Megarhyssa: the small angle x-ray data gives a = 7.25 nm, and the wide angle pattern shows that the protein consists of subunits arranged in a 61 helix, with an axial repeat of 3.06 nm5.

scholarly journals Cardiomyocyte-Specific Circulating Cell-Free Methylated DNA in Esophageal Cancer Patients Treated with Chemoradiation

2021 ◽  
Vol 3 (3) ◽  
pp. 100-112
Author(s):  
Sarah Martinez Roth ◽  
Eveline E. Vietsch ◽  
Megan E. Barefoot ◽  
Marcel O. Schmidt ◽  
Matthew D. Park ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Cardiac Toxicity ◽  
Amplicon Sequencing ◽  
Neoadjuvant Chemoradiation ◽  
Patient Specific ◽  
High Dose ◽  
Specific Cell ◽  
Methylated Dna ◽  
Bisulfite Treatment ◽  
Dose Radiation

Thoracic high-dose radiation therapy (RT) for cancer has been associated with early and late cardiac toxicity. To assess altered rates of cardiomyocyte cell death due to RT we monitored changes in cardiomyocyte-specific, cell-free methylated DNA (cfDNA) shed into the circulation. Eleven patients with distal esophageal cancer treated with neoadjuvant chemoradiation to 50.4 Gy (RT) and concurrent carboplatin and paclitaxel were enrolled. Subjects underwent fasting blood draws prior to the initiation and after completion of RT as well as 4–6 months following RT. An island of six unmethylated CpGs in the FAM101A locus was used to identify cardiomyocyte-specific cfDNA in serum. After bisulfite treatment this specific cfDNA was quantified by amplicon sequencing at a depth of >35,000 reads/molecule. Cardiomyocyte-specific cfDNA was detectable before RT in the majority of patient samples and showed some distinct changes during the course of treatment and recovery. We propose that patient-specific cardiac damages in response to the treatment are indicated by these changes although co-morbidities may obscure treatment-specific events.

scholarly journals High-resolution cryo-EM structure of photosystem II reveals damage from high-dose electron beams

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Koji Kato ◽  
Naoyuki Miyazaki ◽  
Tasuku Hamaguchi ◽  
Yoshiki Nakajima ◽  
Fusamichi Akita ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
Physiological State ◽  
High Dose ◽  
Final State ◽  
X Ray ◽  
Redox States ◽  
X Ray Crystallography ◽  
Cryo Electron Microscopy ◽  
Redox Active ◽  
Beam Damage

AbstractPhotosystem II (PSII) plays a key role in water-splitting and oxygen evolution. X-ray crystallography has revealed its atomic structure and some intermediate structures. However, these structures are in the crystalline state and its final state structure has not been solved. Here we analyzed the structure of PSII in solution at 1.95 Å resolution by single-particle cryo-electron microscopy (cryo-EM). The structure obtained is similar to the crystal structure, but a PsbY subunit was visible in the cryo-EM structure, indicating that it represents its physiological state more closely. Electron beam damage was observed at a high-dose in the regions that were easily affected by redox states, and reducing the beam dosage by reducing frames from 50 to 2 yielded a similar resolution but reduced the damage remarkably. This study will serve as a good indicator for determining damage-free cryo-EM structures of not only PSII but also all biological samples, especially redox-active metalloproteins.

Sign in / Sign up

Export Citation Format

Share Document