scholarly journals Probing the existence of non-thermal Terahertz radiation induced changes of the protein solution structure

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Martin A. Schroer ◽  
Siawosch Schewa ◽  
Andrey Yu. Gruzinov ◽  
Christian Rönnau ◽  
Janine Mia Lahey-Rudolph ◽  
...  
Keyword(s):  
Solution Structure ◽  
Structural Changes ◽  
Thz Radiation ◽  
Biological Macromolecules ◽  
Experimental Proof ◽  
Variable Parameters ◽  
X Ray Scattering ◽  
Radiation Induced ◽  
Induced Changes ◽  
Power Densities

AbstractDuring the last decades discussions were taking place on the existence of global, non-thermal structural changes in biological macromolecules induced by Terahertz (THz) radiation. Despite numerous studies, a clear experimental proof of this effect for biological particles in solution is still missing. We developed a setup combining THz-irradiation with small angle X-ray scattering (SAXS), which is a sensitive method for detecting the expected structural changes. We investigated in detail protein systems with different shape morphologies (bovine serum albumin, microtubules), which have been proposed to be susceptible to THz-radiation, under variable parameters (THz wavelength, THz power densities up to 6.8 mW/cm2, protein concentrations). None of the studied systems and conditions revealed structural changes detectable by SAXS suggesting that the expected non-thermal THz-induced effects do not lead to alterations of the overall structures, which are revealed by scattering from dissolved macromolecules. This leaves us with the conclusion that, if such effects are present, these are either local or outside of the spectrum and power range covered by the present study.

Structural Modifications in Thin Films Caused by Gamma Radiation

2005 ◽  
Vol 480-481 ◽  
pp. 13-20 ◽  
Author(s):  
Khalil Arshak ◽  
Olga Korostynska ◽  
John Henry
Keyword(s):  
Thin Films ◽  
Gamma Radiation ◽  
Structural Changes ◽  
X Ray Diffraction ◽  
Thermal Vacuum ◽  
X Ray ◽  
Structural Modifications ◽  
Thin Oxide Films ◽  
Radiation Induced ◽  
Induced Changes

This paper reports on the gamma radiation-induced changes in thin oxide films deposited by thermal vacuum technique. Structures of various oxides thin films, such as In2O3, SiO and TeO2 and their mixtures in different proportions were studied. The influence of gamma radiation on In2O3/SiO films has resulted in significant changes in the microstructure of this film. Some kind of agglomerations with variable sizes in the range 0.5-3 µm has occurred. After a dose of 8160 µSv an evidence of partial crystallisation was observed with X-ray diffraction. Structural changes in TeO2 thin film were explored by means of Raman spectroscopy. After they have been exposed to g- radiation, a strong peak appeared at 448.83 cm-1, indicating further transformation to g-TeO2 modification.

Defect Structure of Ion-Irradiated Amorphous SiO2

1997 ◽  
Vol 30 (5) ◽  
pp. 618-622 ◽  
Author(s):  
Y. Eyal ◽  
R. Evron ◽  
Y. Cohen
Keyword(s):  
Ion Irradiation ◽  
Chemical Properties ◽  
Atomic Displacement ◽  
Amorphous Sio2 ◽  
X Ray Scattering ◽  
Scattering Centers ◽  
Radiation Induced ◽  
Induced Changes ◽  
Physical And Chemical ◽  
And Chemical Properties

Uniformly enhanced small-angle X-ray scattering intensities of amorphous SiO2, measured following irradiation with 320 keV H+ and He+ beams, are shown to be correlated, irrespective of the incident ion, with the O and Si cumulative displacement yields. Damage by both beams originated primarily from nuclear stopping but, under H+-ion irradiation, contributions from ionization processes were significant as well. At low beam fluences, the irradiated structure is compatible with the presence of stable radiation-induced interstitial-like O and Si atoms and complementary O and Si vacancy-like sites. There is no evidence for recovery near room temperature of the modified structure to the pre-irradiated state or for formation of colloidal-size scattering centers, such as gas bubbles or voids. Thus, ion-irradiation-induced changes in physical and chemical properties of silica seem to be due to the effect of the preserved primary atomic displacement damage.

Ion Beam Modification of High-Tc Superconductors

1989 ◽  
Vol 157 ◽  
Author(s):  
O. Meyer ◽  
J. Geerk ◽  
T. Kroner ◽  
Q. Li ◽  
G. Linker ◽  
...  
Keyword(s):  
Structural Changes ◽  
Ion Irradiation ◽  
Ion Beam ◽  
High Temperature Superconductors ◽  
Lattice Parameter ◽  
Ion Beam Modification ◽  
Radiation Induced ◽  
Htsc Thin Films ◽  
Property Changes ◽  
Induced Changes

ABSTRACTIon irradiation and implantation experiments of high temperature superconductors (HTSC) thin films resulted in many interesting effects. Among those are: (i) the superlinear increase of the resistivity, p, with ion fluence, φ, leading to a metal to insulator transformation, (ii) the large recovery above 150 K of the radiation induced changes of ρ and Tc observed in low temperature irradiation experiments, and (iii) the large structural changes such as the increase of the c-axis lattice parameter with φ, the radiation induced orthorhombic to tetragonal phase transition, and the amorphization. Displaced oxygen atoms play an important role for the observed property changes.

scholarly journals Identification of patterns in diffraction intensities affected by radiation exposure

2012 ◽  
Vol 20 (1) ◽  
pp. 37-48 ◽  
Author(s):  
Dominika Borek ◽  
Zbigniew Dauter ◽  
Zbyszek Otwinowski
Keyword(s):  
Structural Changes ◽  
X Ray Diffraction ◽  
Factors Affecting ◽  
X Ray ◽  
Structure Of Molecules ◽  
Structure Factors ◽  
Unique Reflection ◽  
Radiation Induced ◽  
Value Decomposition ◽  
Induced Changes

In an X-ray diffraction experiment, the structure of molecules and the crystal lattice changes owing to chemical reactions and physical processes induced by the absorption of X-ray photons. These structural changes alter structure factors, affecting the scaling and merging of data collected at different absorbed doses. Many crystallographic procedures rely on the analysis of consistency between symmetry-equivalent reflections, so failure to account for the drift of their intensities hinders the structure solution and the interpretation of structural results. The building of a conceptual model of radiation-induced changes in macromolecular crystals is the first step in the process of correcting for radiation-induced inconsistencies in diffraction data. Here the complexity of radiation-induced changes in real and reciprocal space is analysed using matrix singular value decomposition applied to multiple complete datasets obtained from single crystals. The model consists of a resolution-dependent decay correction and a uniform-per-unique-reflection term modelling specific radiation-induced changes. This model is typically sufficient to explain radiation-induced effects observed in diffraction intensities. This analysis will guide the parameterization of the model, enabling its use in subsequent crystallographic calculations.

А Computer Simulation of Radiation-Induced Structural Changes and Properties of Multiperiod ZrNx/MoNx System

2017 ◽  
Vol 9 (2) ◽  
pp. 02031-1-02031-5
Author(s):  
O. V. Sobol ◽  
◽  
A. A. Meylekhov ◽  
T. V. Bochulia ◽  
V. A. Stolbovoy ◽  
...  
Keyword(s):  
Computer Simulation ◽  
Structural Changes ◽  
Radiation Induced

scholarly journals Space Radiation-Induced Alterations in the Hippocampal Ubiquitin-Proteome System

2021 ◽  
Vol 22 (14) ◽  
pp. 7713
Author(s):  
Alyssa Tidmore ◽  
Sucharita M. Dutta ◽  
Arriyam S. Fesshaye ◽  
William K. Russell ◽  
Vania D. Duncan ◽  
...  
Keyword(s):  
Spatial Memory ◽  
Memory Performance ◽  
Space Radiation ◽  
Label Free ◽  
Proteomic Profiling ◽  
Neurocognitive Deficits ◽  
Male Wistar Rats ◽  
Radiation Induced ◽  
Induced Changes

Exposure of rodents to <20 cGy Space Radiation (SR) impairs performance in several hippocampus-dependent cognitive tasks, including spatial memory. However, there is considerable inter-individual susceptibility to develop SR-induced spatial memory impairment. In this study, a robust label-free mass spectrometry (MS)-based unbiased proteomic profiling approach was used to characterize the composition of the hippocampal proteome in adult male Wistar rats exposed to 15 cGy of 1 GeV/n 48Ti and their sham counterparts. Unique protein signatures were identified in the hippocampal proteome of: (1) sham rats, (2) Ti-exposed rats, (3) Ti-exposed rats that had sham-like spatial memory performance, and (4) Ti-exposed rats that impaired spatial memory performance. Approximately 14% (159) of the proteins detected in hippocampal proteome of sham rats were not detected in the Ti-exposed rats. We explored the possibility that the loss of the Sham-only proteins may arise as a result of SR-induced changes in protein homeostasis. SR-exposure was associated with a switch towards increased pro-ubiquitination proteins from that seen in Sham. These data suggest that the role of the ubiquitin-proteome system as a determinant of SR-induced neurocognitive deficits needs to be more thoroughly investigated.

scholarly journals Impact of [18F]FDG-PET and [18F]FLT-PET-Parameters in Patients with Suspected Relapse of Irradiated Lung Cancer

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 279
Author(s):  
Tine N. Christensen ◽  
Seppo W. Langer ◽  
Gitte Persson ◽  
Klaus Richter Larsen ◽  
Annemarie G. Amtoft ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Overall Survival ◽  
Fdg Pet ◽  
Tumor Volume ◽  
High Dose ◽  
Flt Pet ◽  
Pet Ct ◽  
Radiation Induced ◽  
Fdg Pet Ct ◽  
Induced Changes

Radiation-induced changes may cause a non-malignant high 2-deoxy-2-[18F]fluoro-d-glucose (FDG)-uptake. The 3′-deoxy-3′-[18F]fluorothymidine (FLT)-PET/CT performs better in the differential diagnosis of inflammatory changes and lung lesions with a higher specificity than FDG-PET/CT. We investigated the association between post-radiotherapy FDG-PET-parameters, FLT-PET-parameters, and outcome. Sixty-one patients suspected for having a relapse after definitive radiotherapy for lung cancer were included. All the patients had FDG-PET/CT and FLT-PET/CT. FDG-PET- and FLT-PET-parameters were collected from within the irradiated high-dose volume (HDV) and from recurrent pulmonary lesions. For associations between PET-parameters and relapse status, respectively, the overall survival was analyzed. Thirty patients had a relapse, of these, 16 patients had a relapse within the HDV. FDG-SUVmax and FLT-SUVmax were higher in relapsed HDVs compared with non-relapsed HDVs (median FDG-SUVmax: 12.8 vs. 4.2; p < 0.001; median FLT-SUVmax 3.9 vs. 2.2; p < 0.001). A relapse within HDV had higher FDG-SUVpeak (median FDG-SUVpeak: 7.1 vs. 3.5; p = 0.014) and was larger (median metabolic tumor volume (MTV50%): 2.5 vs. 0.7; 0.014) than the relapsed lesions outside of HDV. The proliferative tumor volume (PTV50%) was prognostic for the overall survival (hazard ratio: 1.07 pr cm3 [1.01–1.13]; p = 0.014) in the univariate analysis, but not in the multivariate analysis. FDG-SUVmax and FLT-SUVmax may be helpful tools for differentiating the relapse from radiation-induced changes, however, they should not be used definitively for relapse detection.

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