scholarly journals Secondary Radiation in Ion Therapy and Theranostics: A Review

2021 ◽  
Vol 8 ◽  
Author(s):  
Maitreyee Nandy
Keyword(s):  
Nuclear Reactions ◽  
Nuclear Interaction ◽  
Target Volume ◽  
Primary Beam ◽  
Secondary Radiation ◽  
Ion Therapy ◽  
Risk Of Exposure ◽  
Beam Delivery ◽  
Treatment Procedures

Ion therapy has emerged as one of the preferred treatment procedures in some selective indication of cancer. The actual dose delivered to the target volume may differ from the planned dose due to wrong positioning of the patient and organ movement during beam delivery. On the other hand, some healthy tissues outside the planned volume may be exposed to radiation dose. It is necessary to determine the primary particle range and the actual exposed volume during irradiation. Many proposed techniques use secondary radiation for the purpose. The secondary radiation consists mainly of neutrons, charged fragments, annihilation photons, among others, and prompt gammas. These are produced through nuclear interaction of the primary beam with the beam line and the patient’s body tissue. Besides its usefulness in characterizing the primary beam, the secondary radiation contributes to the risk of exposure of different tissues. Secondary radiation has significant contribution in theranostics, a comparatively new branch of medicine, which combines diagnosis and therapy. Many authors have made detailed study of the dose delivered to the patient by the secondary radiation and its effects. They have also studied the correlation of secondary charged particles with the beam range and the delivered dose. While these studies have been carried out in great detail in the case of proton and carbon therapy, there are fewer analyses for theranostics. In the present review, a brief account of the studies carried out so far on secondary radiation in ion therapy, its effect, and the role of nuclear reactions is given.

scholarly journals Importation of Ticks on Companion Animals and the Risk of Spread of Tick-Borne Diseases to Non-Endemic Regions in Europe

Animals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 6
Author(s):  
Alicja Buczek ◽  
Weronika Buczek
Keyword(s):  
Tick Species ◽  
Potential Role ◽  
Human Mobility ◽  
Companion Animals ◽  
Rhipicephalus Sanguineus ◽  
European Countries ◽  
Rapid Spread ◽  
Risk Of Exposure ◽  
Geographic Regions

Increased human mobility elevates the risk of exposure of companion animals travelling with their owners or imported from other regions to tick attacks. In this study, we highlight the potential role of dogs and cats taken for tourist trips or imported animals in the spread of ticks and tick-borne pathogens. The Rhipicephalus sanguineus tick, which is a vector of numerous pathogens causing diseases in animals and humans, is imported most frequently from endemic areas to many European countries. Additionally, alien tick species with high epizootic and epidemiological importance can be imported on dogs from other continents. Companion animals play an even greater role in the spread of autochthonous tick species and transmission of tick pathogens to other animals and humans. Although the veterinary and medical effects of the parasitism of ticks carried by companion animals travelling with owners or imported animals are poorly assessed, these animals seem to play a role in the rapid spread of tick-borne diseases. Development of strategies for protection of the health of companion animals in different geographic regions should take into account the potential emergence of unknown animal tick-borne diseases that can be transmitted by imported ticks.

scholarly journals On the distribution of the scattered Röntgen radiation

1912 ◽  
Vol 86 (589) ◽  
pp. 478-494 ◽  
Keyword(s):  
Wave Front ◽  
Scattered Radiation ◽  
Single Electron ◽  
Primary Beam ◽  
Secondary Radiation ◽  
Electromagnetic Forces ◽  
Probable Explanation ◽  
The Mean ◽  
Most Probable Explanation

The fact that a substance through which Röntgen rays from a focus tube are passing becomes itself a source of secondary Röntgen rays has long- been known. The most probable explanation was given by Prof. Sir J. J. Thomson. If a Röntgen pulse is due to the acceleration of a charged electron, then if the electrons in the atom are free to move under the action of the electromagnetic forces in the wave front of the primary Röntgen pulse, their motion will be accelerated during the passage of the latter through the atom, and they will themselves become sources of secondary Röntgen radiation. Considering only a single electron, the intensity of the secondary radiation at any angle α with the direction of motion will be proportional to sin 2 α . If the primary beam is unpolarised, the motion of the electron may have any direction in the plane at right angles to the primary beam. The intensity of the scattered radiation in the direction θ with the primary beam is thus the mean of all the values of sin 2 α for that direction. It can easily be shown that this is proportional to 1 + cos 2 θ . If I' θ is the intensity of the scattered radiation in the direction θ , we thus have I' θ = I' π /2 (1 + cos 2 θ ).

Description of (Hyper-)Fragments in Hadron-Induced Reactions

Symmetry ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1887
Author(s):  
Theodoros Gaitanos
Keyword(s):  
Nuclear Reactions ◽  
Heavy Ion ◽  
Nuclear Fragmentation ◽  
Equilibrium Dynamics ◽  
Ion Collisions ◽  
Light Ions ◽  
Classical Transport ◽  
Nuclear Targets ◽  
Fragmentation Processes

In this article we review the important role of non-equilibrium dynamics in reactions induced by ions and hadron beams to understand the fragmentation processes inside hadronic media. We discuss the single-particle dynamics in specific sources such as spectators in heavy-ion collisions and residual nuclear targets in hadron-induced reactions. Particular attention is given to the dynamics of hyperons. We further discuss the question regarding the onset of local instabilities, which are relevant for the appearance of fragmentation phenomena in nuclear reactions. We apply the theoretical formalism, that is, semi-classical transport embedded with statistical methods of nuclear fragmentation, to reactions induced by light ions and hadron beams. We discuss the results of nuclear fragmentation and, in particular, examine the formation of hypernuclei. Such studies are important for obtaining a deeper understanding of the equation of state in fragmenting matter and are relevant for forthcoming experiments, such as PANDA at FAIR and J-PARC in Japan.

COMBINING CLUSTER STRUCTURE WITH REACTIONS

2006 ◽  
Vol 21 (31n33) ◽  
pp. 2419-2428
Author(s):  
MARTIN FREER
Keyword(s):  
Nuclear Reactions ◽  
Cluster Structure ◽  
Resonant Scattering ◽  
Made In

An examination of the role of the cluster in nuclear reactions is made in the longstanding case of 12 C +12 C cluster resonances in 24 Mg . A description of both resonant scattering and breakup measurements can be found in terms of shape isomeric cluster structures.

scholarly journals Nowhere to Hide: Radio-faint AGN in GOODS-N field

2018 ◽  
Vol 619 ◽  
pp. A48 ◽  
Author(s):  
J. F. Radcliffe ◽  
M. A. Garrett ◽  
T. W. B. Muxlow ◽  
R. J. Beswick ◽  
P. D. Barthel ◽  
...  
Keyword(s):  
Galaxy Evolution ◽  
Cosmic Time ◽  
Primary Beam ◽  
Radio Sources ◽  
Source Population ◽  
Wide Field ◽  
Beam Model ◽  
Phase Errors ◽  
Long Baseline

Context. The occurrence of active galactic nuclei (AGN) is critical to our understanding of galaxy evolution and formation. Radio observations provide a crucial, dust-independent tool to study the role of AGN. However, conventional radio surveys of deep fields ordinarily have arc-second scale resolutions often insufficient to reliably separate radio emission in distant galaxies originating from star-formation and AGN-related activity. Very long baseline interferometry (VLBI) can offer a solution by identifying only the most compact radio emitting regions in galaxies at cosmological distances where the high brightness temperatures (in excess of 105 K) can only be reliably attributed to AGN activity. Aims. We present the first in a series of papers exploring the faint compact radio population using a new wide-field VLBI survey of the GOODS-N field. This will expand upon previous surveys, permitting the characterisation of the faint, compact radio source population in the GOODS-N field. The unparalleled sensitivity of the European VLBI Network (EVN) will probe a luminosity range rarely seen in deep wide-field VLBI observations, thus providing insights into the role of AGN to radio luminosities of the order 1022 WHz−1 across cosmic time. Methods. The newest VLBI techniques are used to completely cover an entire 7′̣5 radius area to milliarcsecond resolutions, while bright radio sources (S > 0.1 mJy) are targeted up to 25′ from the pointing centre. Multi-source self-calibration, and a primary beam model for the EVN array are used to correct for residual phase errors and primary beam attenuation respectively. Results. This paper presents the largest catalogue of VLBI detected sources in GOODS-N comprising of 31 compact radio sources across a redshift range of 0.11–3.44, almost three times more than previous VLBI surveys in this field. We provide a machine-readable catalogue and introduce the radio properties of the detected sources using complementary data from the e-MERLIN Galaxy Evolution survey (eMERGE).

Investigation on the role of integrated PET/MRI for target volume definition and radiotherapy planning in patients with high grade glioma

2014 ◽  
Vol 112 (3) ◽  
pp. 425-429 ◽  
Author(s):  
Pierina Navarria ◽  
Giacomo Reggiori ◽  
Federico Pessina ◽  
Anna Maria Ascolese ◽  
Stefano Tomatis ◽  
...  
Keyword(s):  
High Grade Glioma ◽  
Target Volume ◽  
Radiotherapy Planning ◽  
High Grade ◽  
Target Volume Definition

scholarly journals Are Further Cross Section Measurements Necessary for Space Radiation Protection or Ion Therapy Applications? Helium Projectiles

2020 ◽  
Vol 8 ◽  
Author(s):  
John W. Norbury ◽  
Giuseppe Battistoni ◽  
Judith Besuglow ◽  
Luca Bocchini ◽  
Daria Boscolo ◽  
...  
Keyword(s):  
Radiation Protection ◽  
Cross Section ◽  
Cross Sections ◽  
Nuclear Reactions ◽  
Production Cross ◽  
Cosmic Ray ◽  
Space Radiation ◽  
Radiation Shielding ◽  
Light Ions ◽  
Ion Therapy

The helium (4He) component of the primary particles in the galactic cosmic ray spectrum makes significant contributions to the total astronaut radiation exposure. 4He ions are also desirable for direct applications in ion therapy. They contribute smaller projectile fragmentation than carbon (12C) ions and smaller lateral beam spreading than protons. Space radiation protection and ion therapy applications need reliable nuclear reaction models and transport codes for energetic particles in matter. Neutrons and light ions (1H, 2H, 3H, 3He, and 4He) are the most important secondary particles produced in space radiation and ion therapy nuclear reactions; these particles penetrate deeply and make large contributions to dose equivalent. Since neutrons and light ions may scatter at large angles, double differential cross sections are required by transport codes that propagate radiation fields through radiation shielding and human tissue. This work will review the importance of 4He projectiles to space radiation and ion therapy, and outline the present status of neutron and light ion production cross section measurements and modeling, with recommendations for future needs.

scholarly journals Role of nuclear reactions on stellar evolution of intermediate-mass stars

2018 ◽  
Vol 940 ◽  
pp. 012050
Author(s):  
H Möller ◽  
S Jones ◽  
T Fischer ◽  
G Martínez-Pinedo
Keyword(s):  
Stellar Evolution ◽  
Nuclear Reactions ◽  
Intermediate Mass ◽  
Intermediate Mass Stars
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