1
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Bochtler M. X-rays, electrons, and neutrons as probes of atomic matter. Structure 2024; 32:630-643.e6. [PMID: 38412856 DOI: 10.1016/j.str.2024.01.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 03/21/2023] [Accepted: 01/31/2024] [Indexed: 02/29/2024]
Abstract
X-rays, electrons, and neutrons probe different properties of matter. X-rays feel electron density (ED). Electrons sense the electrostatic potential (ESP) of electrons and nuclei. Neutrons are sensitive to nuclear coherent scattering length (NCSL). While NCSL maps are widely understood to be different, ED and ESP maps are tacitly assumed to be similar. Here, I show that the belief in ED and ESP map equivalence is mistaken, but contains a grain of truth. Using density functional theory (DFT), the Bethe-Mott (BM) relation, and the Thomas-Fermi (TF) and Cromer-Mann (CM) atomic models, I show that ED and ESP maps are indeed more similar to each other than to NCSL maps. Nevertheless, peak and integrated map values depend differently on the atomic order number and on the contributions from electrons in the inner and outer CM shells. ED and ESP maps also differ in the sign and relative magnitude of excess charge effects.
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Affiliation(s)
- Matthias Bochtler
- IIMCB, Trojdena 4, 02-109 Warsaw, Poland; Polish Academy of Sciences, IBB, Pawinskiego 5a, 02-106 Warsaw, Poland.
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2
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Marcelot O, Marcelot C, Rolando S. Limitations and Drawbacks of DQE Estimation Methods Applied to Electron Detectors. Microscopy (Oxf) 2024:dfae016. [PMID: 38498372 DOI: 10.1093/jmicro/dfae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/27/2024] [Accepted: 03/15/2024] [Indexed: 03/20/2024] Open
Abstract
The DQE is generally accepted as the main figure of merit for the comparison between electron detectors, and most of the time given as a unique number at the Nyquist frequency while it is known to vary with electron dose. It is usually estimated thanks to a method improved by McMullan in 2009. The purpose of this work is to analyse and to criticize this DQE extraction method on the basis of measurement and model results, and to give recommendations for fair comparison between detectors, wondering if the DQE is the right figure of merit for electron detectors.
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3
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McDermott PN. Internal lead shielding for clinical electron treatments. J Appl Clin Med Phys 2024; 25:e14196. [PMID: 37922411 DOI: 10.1002/acm2.14196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 09/27/2023] [Accepted: 10/18/2023] [Indexed: 11/05/2023] Open
Abstract
Electron beams are often used to treat superficial lesions of the lip, cheek, nose, and ear. Lead is frequently used to block distal structures. It is customary to place an internal bolus of low atomic number in between the tissue and the lead to reduce electron backscatter from the lead. Space for the lead and the internal bolus is quite limited. A previous method for estimating the thickness of the lead plus internal bolus is not self-consistent and leads to a larger than necessary thickness. A new method is described here to provide a quick, accurate, and self-consistent estimate of the minimum necessary thickness of the internal bolus and the lead for incident electron beam energies of 4, 6, 8, 9, and 10 MeV as a function of the thickness of the overlying tissue. This method limits the dose enhancement at the tissue/bolus interface due to the underlying lead to 10%. Measurements made with gafchromic film validate this methodology.
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Affiliation(s)
- Patrick N McDermott
- Beaumont Health, William Beaumont University Hospital, Royal Oak, Michigan, USA
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4
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Prazyan A, Podlutskii M, Volkova P, Kazakova E, Bitarishvili S, Shesterikova E, Saburov V, Makarenko E, Lychenkova M, Korol M, Kazakov E, Moiseev A, Geras’kin S, Bondarenko E. Comparative Analysis of the Effect of Gamma-, Electron, and Proton Irradiation on Transcriptomic Profile of Hordeum vulgare L. Seedlings: In Search for Molecular Contributors to Abiotic Stress Resilience. Plants (Basel) 2024; 13:342. [PMID: 38337875 PMCID: PMC10857502 DOI: 10.3390/plants13030342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/19/2024] [Accepted: 01/20/2024] [Indexed: 02/12/2024]
Abstract
The development of adaptation strategies for crops under ever-changing climate conditions is a critically important food security issue. Studies of barley responses to ionising radiation showed that this evolutionarily ancient stress factor can be successfully used to identify molecular pathways involved in adaptation to a range of abiotic stressors. In order to identify potential molecular contributors to abiotic stress resilience, we examined the transcriptomic profiles of barley seedlings after exposure to γ-rays, electrons, and protons. A total of 553 unique differentially expressed genes with increased expression and 124 with decreased expression were detected. Among all types of radiation, the highest number of differentially expressed genes was observed in electron-irradiated samples (428 upregulated and 56 downregulated genes). Significant upregulation after exposure to the three types of radiation was shown by a set of ROS-responsive genes, genes involved in DNA repair, cell wall metabolism, auxin biosynthesis and signalling, as well as photosynthesis-related genes. Most of these genes are known to be involved in plant ROS-mediated responses to other abiotic stressors, especially with genotoxic components, such as heavy metals and drought. Ultimately, the modulation of molecular pathways of plant responses to ionising radiation may be a prospective tool for stress tolerance programmes.
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Affiliation(s)
- Alexander Prazyan
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Mikhail Podlutskii
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | | | - Elizaveta Kazakova
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Sofia Bitarishvili
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Ekaterina Shesterikova
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Vyacheslav Saburov
- A. Tsyb Medical Radiological Research Centre—Branch of the National Medical Research Radiological Centre of the Ministry of Health of the Russian Federation, 249036 Obninsk, Russia
| | - Ekaterina Makarenko
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Maria Lychenkova
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Marina Korol
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Evgeniy Kazakov
- A. Tsyb Medical Radiological Research Centre—Branch of the National Medical Research Radiological Centre of the Ministry of Health of the Russian Federation, 249036 Obninsk, Russia
| | - Alexander Moiseev
- A. Tsyb Medical Radiological Research Centre—Branch of the National Medical Research Radiological Centre of the Ministry of Health of the Russian Federation, 249036 Obninsk, Russia
| | - Stanislav Geras’kin
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
| | - Ekaterina Bondarenko
- Russian Institute of Radiology and Agroecology of National Research Centre “Kurchatov Institute”, 249035 Obninsk, Russia
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Matsuya Y, Yoshii Y, Kusumoto T, Akamatsu K, Hirata Y, Sato T, Kai T. A step-by-step simulation code for estimating yields of water radiolysis species based on electron track-structure mode in the PHITS code. Phys Med Biol 2024; 69:035005. [PMID: 38157551 DOI: 10.1088/1361-6560/ad199b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
Objective. Time-dependent yields of chemical products resulting from water radiolysis play a great role in evaluating DNA damage response after exposure to ionizing radiation. Particle and Heavy Ion Transport code System (PHITS) is a general-purpose Monte Carlo simulation code for radiation transport, which simulates atomic interactions originating from discrete energy levels of ionizations and electronic excitations as well as molecular excitations as physical stages. However, no chemical code for simulating water radiolysis products exists in the PHITS package.Approach.Here, we developed a chemical simulation code dedicated to the PHITS code, hereafter calledPHITS-Chemcode, which enables the calculation of theGvalues of water radiolysis species (•OH, eaq-, H2, H2O2etc) by electron beams.Main results.The estimatedGvalues during 1 μs are in agreement with the experimental ones and other simulations. ThisPHITS-Chemcode also simulates the radiolysis in the presence of OH radical scavengers, such as tris(hydroxymethyl)aminomethane and dimethyl sulfoxide. Thank to this feature, the contributions of direct and indirect effects on DNA damage induction under various scavenging capacities can be analyzed.Significance.This chemical code coupled with PHITS could contribute to elucidating the mechanism of radiation effects by connecting physical, physicochemical, and chemical processes.
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Affiliation(s)
- Yusuke Matsuya
- Nuclear Science and Engineering Center, Research Group for Radiation Transport Analysis, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai, Ibaraki, 319-1195, Japan
- Faculty of Health Sciences, Hokkaido University, Kita-12 Nishi-5, Kita-ku, Sapporo, Hokkaido, 060-0812, Japan
| | - Yuji Yoshii
- Department of Radiological Technology, Faculty of Health Sciences, Hokkaido University of Science, Maeda 7-15, Teine-ku, Sapporo 006-8585, Japan
| | - Tamon Kusumoto
- National Institutes for Quantum Science and Technology, 4-9-1 Anagawa, Inage-ku, 263-8555 Chiba, Japan
| | - Ken Akamatsu
- Institute for Quantum life Science, Quantum Life and Medical Science Directorate, National Institutes of Quantum and Radiological Science and Technology (QST), 8-1-7 Umemidai, Kizugawa-shi, Kyoto, 619-0215, Japan
| | - Yuho Hirata
- Nuclear Science and Engineering Center, Research Group for Radiation Transport Analysis, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai, Ibaraki, 319-1195, Japan
| | - Tatsuhiko Sato
- Nuclear Science and Engineering Center, Research Group for Radiation Transport Analysis, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai, Ibaraki, 319-1195, Japan
| | - Takeshi Kai
- Nuclear Science and Engineering Center, Research Group for Radiation Transport Analysis, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata, Tokai, Ibaraki, 319-1195, Japan
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Demyashkin G, Karakaeva E, Saakian S, Tarusova N, Guseinova A, Vays A, Gotovtsev K, Atiakshin D, Shegai P, Kaprin A. Comparative Characterisation of Proliferation and Apoptosis of Colonic Epithelium after Electron Irradiation with 2 GY and 25 GY. Int J Mol Sci 2024; 25:1196. [PMID: 38256269 PMCID: PMC10817034 DOI: 10.3390/ijms25021196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/03/2024] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
Development of new techniques for multimodal treatment and diagnostics of various neoplasms and the improvement of current techniques can significantly increase the life expectancy of patients with carcinomas of the colon and abdominal-cavity organs, since prevention of various side effects of radiation therapy is one of the main problems of oncological care. Electron irradiation is one of the most promising types of radiation therapy. There are no data on proliferation and apoptosis of the colon epithelium after irradiation with electrons, especially in different modes (single and summary). Morphological evaluation of apoptosis and proliferation of colonic epithelium after local irradiation with electrons were conducted at doses of 2 Gy (Gray) and 25 Gy. Colon fragments from sexually mature Wistar rats (n = 50, body weight 200 ± 10 g) were divided into three groups: I-control (n = 10); II-experimental group (n = 20; local single electron irradiation at a dose of 2 Gy); III-experimental group (n = 30) with local fractional irradiation with electrons at a total dose of 25 Gy. They were studied using light microscopy using hematoxylin and eosin staining and immunohistochemical reactions with antibodies to Ki-67 and caspase-3 (Cas3). Morphological disorders were accompanied by increased expression of pro-apoptotic molecules (caspase-3), and the period of regeneration by proliferative marker (Ki-67). Colon electron irradiation led to disturbances in the histoarchitecture of varying severity, and an increase in cell apoptosis was observed (increased expression of caspase-3 and decrease in Ki-67). In addition, modulation of the PI3K/AKT and MAPK/ERK signalling pathways was detected. The most pronounced destructive changes were observed in the group of 25 Gy fractionated electron irradiation.
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Affiliation(s)
- Grigory Demyashkin
- Laboratory of Histology and Immunohistochemistry, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia
| | - Elza Karakaeva
- Department of Pathomorphology, National Medical Research Centre of Radiology, Ministry of Health of Russia, 125284 Moscow, Russia
| | - Susanna Saakian
- Department of Pathomorphology, National Medical Research Centre of Radiology, Ministry of Health of Russia, 125284 Moscow, Russia
| | - Natalia Tarusova
- Laboratory of Histology and Immunohistochemistry, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia
| | - Amina Guseinova
- Laboratory of Histology and Immunohistochemistry, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia
| | - Anita Vays
- Laboratory of Histology and Immunohistochemistry, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia
| | - Konstantin Gotovtsev
- Laboratory of Histology and Immunohistochemistry, I.M. Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia
| | - Dmitrii Atiakshin
- Research and Educational Resource Center for Immunophenotyping, Digital Spatial Profiling and Ultrastructural Analysis Innovative Technologies, RUDN University, 117198 Moscow, Russia
| | - Petr Shegai
- Department of Pathomorphology, National Medical Research Centre of Radiology, Ministry of Health of Russia, 125284 Moscow, Russia
| | - Andrey Kaprin
- Department of Pathomorphology, National Medical Research Centre of Radiology, Ministry of Health of Russia, 125284 Moscow, Russia
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Konradsson E, Wahlqvist P, Thoft A, Blad B, Bäck S, Ceberg C, Petersson K. Beam control system and output fine-tuning for safe and precise delivery of FLASH radiotherapy at a clinical linear accelerator. Front Oncol 2024; 14:1342488. [PMID: 38304871 PMCID: PMC10830783 DOI: 10.3389/fonc.2024.1342488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Accepted: 01/03/2024] [Indexed: 02/03/2024] Open
Abstract
Introduction We have previously adapted a clinical linear accelerator (Elekta Precise, Elekta AB) for ultra-high dose rate (UHDR) electron delivery. To enhance reliability in future clinical FLASH radiotherapy trials, the aim of this study was to introduce and evaluate an upgraded beam control system and beam tuning process for safe and precise UHDR delivery. Materials and Methods The beam control system is designed to interrupt the beam based on 1) a preset number of monitor units (MUs) measured by a monitor detector, 2) a preset number of pulses measured by a pulse-counting diode, or 3) a preset delivery time. For UHDR delivery, an optocoupler facilitates external control of the accelerator's thyratron trigger pulses. A beam tuning process was established to maximize the output. We assessed the stability of the delivery, and the independent interruption capabilities of the three systems (monitor detector, pulse counter, and timer). Additionally, we explored a novel approach to enhance dosimetric precision in the delivery by synchronizing the trigger pulse with the charging cycle of the pulse forming network (PFN). Results Improved beam tuning of gun current and magnetron frequency resulted in average dose rates at the dose maximum at isocenter distance of >160 Gy/s or >200 Gy/s, with or without an external monitor chamber in the beam path, respectively. The delivery showed a good repeatability (standard deviation (SD) in total film dose of 2.2%) and reproducibility (SD in film dose of 2.6%). The estimated variation in DPP resulted in an SD of 1.7%. The output in the initial pulse depended on the PFN delay time. Over the course of 50 measurements employing PFN synchronization, the absolute percentage error between the delivered number of MUs calculated by the monitor detector and the preset MUs was 0.8 ± 0.6% (mean ± SD). Conclusion We present an upgraded beam control system and beam tuning process for safe and stable UHDR electron delivery of hundreds of Gy/s at isocenter distance at a clinical linac. The system can interrupt the beam based on monitor units and utilize PFN synchronization for improved dosimetric precision in the dose delivery, representing an important advancement toward reliable clinical FLASH trials.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Pontus Wahlqvist
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Andreas Thoft
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Börje Blad
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Sven Bäck
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Kristoffer Petersson
- Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
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McGuinness KN, Fehon N, Feehan R, Miller M, Mutter AC, Rybak LA, Nam J, AbuSalim JE, Atkinson JT, Heidari H, Losada N, Kim JD, Koder RL, Lu Y, Silberg JJ, Slusky JSG, Falkowski PG, Nanda V. The energetics and evolution of oxidoreductases in deep time. Proteins 2024; 92:52-59. [PMID: 37596815 DOI: 10.1002/prot.26563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 07/06/2023] [Indexed: 08/20/2023]
Abstract
The core metabolic reactions of life drive electrons through a class of redox protein enzymes, the oxidoreductases. The energetics of electron flow is determined by the redox potentials of organic and inorganic cofactors as tuned by the protein environment. Understanding how protein structure affects oxidation-reduction energetics is crucial for studying metabolism, creating bioelectronic systems, and tracing the history of biological energy utilization on Earth. We constructed ProtReDox (https://protein-redox-potential.web.app), a manually curated database of experimentally determined redox potentials. With over 500 measurements, we can begin to identify how proteins modulate oxidation-reduction energetics across the tree of life. By mapping redox potentials onto networks of oxidoreductase fold evolution, we can infer the evolution of electron transfer energetics over deep time. ProtReDox is designed to include user-contributed submissions with the intention of making it a valuable resource for researchers in this field.
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Affiliation(s)
- Kenneth N McGuinness
- Department of Natural Sciences, Caldwell University, Caldwell, New Jersey, USA
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey, USA
| | - Nolan Fehon
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Ryan Feehan
- Computational Biology Program, The University of Kansas, Lawrence, Kansas, USA
| | - Michelle Miller
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Andrew C Mutter
- Department of Physics, The City College of New York, New York, New York, USA
| | - Laryssa A Rybak
- Department of Physics, The City College of New York, New York, New York, USA
| | - Justin Nam
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey, USA
| | - Jenna E AbuSalim
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey, USA
| | - Joshua T Atkinson
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, USA
| | - Hirbod Heidari
- Department of Chemistry, University of Texas at Austin, Austin, Texas, USA
| | - Natalie Losada
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey, USA
| | - J Dongun Kim
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Ronald L Koder
- Department of Physics, The City College of New York, New York, New York, USA
| | - Yi Lu
- Department of Chemistry, University of Texas at Austin, Austin, Texas, USA
| | - Jonathan J Silberg
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas, USA
| | - Joanna S G Slusky
- Computational Biology Program, The University of Kansas, Lawrence, Kansas, USA
- Department of Molecular Biosciences, The University of Kansas, Lawrence, Kansas, USA
| | - Paul G Falkowski
- Environmental Biophysics and Molecular Ecology Program, Department of Marine and Coastal Sciences, Rutgers University, New Brunswick, New Jersey, USA
- Department of Earth and Planetary Sciences, Rutgers University, New Brunswick, New Jersey, USA
| | - Vikas Nanda
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, New Jersey, USA
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
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Lei T, Shi X, Ruan X, Liu F, Xiang X. Unveiling Bacterial Autophagosomes in Human Intracranial Aneurysm Wall Tissue: A Rare Insight. Stroke 2023; 54:e498-e499. [PMID: 37823306 DOI: 10.1161/strokeaha.123.044829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023]
Affiliation(s)
- Ting Lei
- Department of Neurosurgery, Fuxing Hospital (T.L., X.S., X.X.), Capital Medical University, Beijing, People's Republic of China
- Department of Neurosurgery, Sanbo Brain Hospital (T.L., X.S., F.L., X.X.), Capital Medical University, Beijing, People's Republic of China
| | - Xiang'en Shi
- Department of Neurosurgery, Fuxing Hospital (T.L., X.S., X.X.), Capital Medical University, Beijing, People's Republic of China
- Department of Neurosurgery, Sanbo Brain Hospital (T.L., X.S., F.L., X.X.), Capital Medical University, Beijing, People's Republic of China
| | | | - Fangjun Liu
- Department of Neurosurgery, Sanbo Brain Hospital (T.L., X.S., F.L., X.X.), Capital Medical University, Beijing, People's Republic of China
| | - Xin Xiang
- Department of Neurosurgery, Fuxing Hospital (T.L., X.S., X.X.), Capital Medical University, Beijing, People's Republic of China
- Department of Neurosurgery, Sanbo Brain Hospital (T.L., X.S., F.L., X.X.), Capital Medical University, Beijing, People's Republic of China
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10
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Hoffmann C, Ringbaek T, Eckstein A, Deya W, Santiago A, Heintz M, Lübcke W, Indenkämpen F, Sauerwein W, Flühs A, Le Guin C, Huettmann A, von Tresckow J, Göricke S, Deuschl C, Moliavi S, Poettgen C, Gauler T, Guberina N, Johansson P, Bechrakis N, Stuschke M, Guberina M. Long-Term Follow-Up of Patients with Conjunctival Lymphoma after Individualized Lens-Sparing Electron Radiotherapy: Results from a Longitudinal Study. Cancers (Basel) 2023; 15:5433. [PMID: 38001692 PMCID: PMC10670077 DOI: 10.3390/cancers15225433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 11/02/2023] [Accepted: 11/11/2023] [Indexed: 11/26/2023] Open
Abstract
Irradiation with electrons is the primary treatment regime for localized conjunctival low-grade lymphomas. However, radiation-induced cataracts are a major cause of treatment-related morbidity. This study investigates whether lens-sparing electron irradiation produces sufficient disease control rates while preventing cataract formation. All consecutive patients with strictly conjunctival, low-grade Ann Arbor stage IE lymphoma treated with superficial electron irradiation between 1999 and 2021 at our department were reviewed. A total of 56 patients with 65 treated eyes were enrolled with a median follow-up of 65 months. The median dose was 30.96 Gy. A lens-spearing technique featuring a hanging rod blocking the central beam axis was used in 89.2% of all cases. Cumulative incidences of 5- and 10-year infield recurrences were 4.3% and 14.6%, incidences of 5- and 10-year outfield progression were 10.4% and 13.4%. We used patients with involvement of retroorbital structures treated with whole-orbit photon irradiation without lens protection-of which we reported in a previous study-as a control group. The cumulative cataract incidence for patients treated with electrons and lens protection was significantly lower (p = 0.005) when compared to patients irradiated without lens protection. Thus, electrons are an effective treatment option for conjunctival low-grade lymphomas. The presented lens-sparing technique effectively prevents cataract formation.
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Affiliation(s)
- Christian Hoffmann
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
| | - Toke Ringbaek
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Anja Eckstein
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Ophthalmology, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany
| | - Wolfgang Deya
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Alina Santiago
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Martin Heintz
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Wolfgang Lübcke
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Frank Indenkämpen
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Wolfgang Sauerwein
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
| | - Andrea Flühs
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- Department of Radiotherapy, Medical Physics Section, University Hospital Essen, 45147 Essen, Germany
| | - Claudia Le Guin
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Ophthalmology, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany
| | - Andreas Huettmann
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Hematology, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany
| | - Julia von Tresckow
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Hematology, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany
| | - Sophia Göricke
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147 Essen, Germany
| | - Cornelius Deuschl
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Institute for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, 45147 Essen, Germany
| | - Sourour Moliavi
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
| | - Christoph Poettgen
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
| | - Thomas Gauler
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
| | - Nika Guberina
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
| | - Patricia Johansson
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Institute of Cell Biology (Cancer Research), Faculty of Medicine, University of Duisburg-Essen, 45147 Essen, Germany
| | - Nikolaos Bechrakis
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- Department of Ophthalmology, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany
| | - Martin Stuschke
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, 45147 Essen, Germany
| | - Maja Guberina
- Department of Radiotherapy, West German Cancer Centre, University Hospital Essen, 45147 Essen, Germany (M.G.)
- National Center for Tumor Diseases (NCT) West, Campus Essen, 45147 Essen, Germany
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, 45147 Essen, Germany
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Konradsson E, Szecsenyi RE, Adrian G, Coskun M, Børresen B, Arendt ML, Erhart K, Bäck SÅ, Petersson K, Ceberg C. Evaluation of intensity-modulated electron FLASH radiotherapy in a clinical setting using veterinary cases. Med Phys 2023; 50:6569-6579. [PMID: 37696040 DOI: 10.1002/mp.16737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/08/2023] [Accepted: 08/29/2023] [Indexed: 09/13/2023] Open
Abstract
PURPOSE The increased normal tissue tolerance for FLASH radiotherapy (FLASH-RT), as compared to conventional radiotherapy, was first observed in ultra-high dose rate electron beams. Initial clinical trials in companion animals have revealed a high risk of developing osteoradionecrosis following high-dose single-fraction electron FLASH-RT, which may be related to inhomogeneities in the dose distribution. In the current study, we aim to evaluate the possibilities of intensity-modulated electron FLASH-RT in a clinical setting to ensure a homogeneous dose distribution in future veterinary and human clinical trials. METHODS Our beam model in the treatment planning system electronRT (.decimal, LLC, Sanford, FL, USA) was based on a 10-MeV electron beam from a clinical linear accelerator used to treat veterinary patients with FLASH-RT in a clinical setting. In electronRT, the beam can be intensity-modulated using tungsten island blocks in the electron block cutout, and range-modulated using a customized bolus with variable thickness. Modulations were first validated in a heterogeneous phantom by comparing measured and calculated dose distributions. To evaluate the impact of intensity modulation in superficial single-fraction FLASH-RT, a treatment planning study was conducted, including eight canine cancer patient cases with simulated tumors in the head-and-neck region. For each case, treatment plans with and without intensity modulation were created for a uniform bolus and a range-modulating bolus. Treatment plans were evaluated using a target dose homogeneity index (HI), a conformity index (CI), the near-maximum dose outside the target (D 2 % , Body - PTV ${D_{2{\mathrm{\% }},{\mathrm{\ Body}} - {\mathrm{PTV}}}}$ ), and the near-minimum dose to the target (D 98 % ${D_{98\% }}$ ). RESULTS By adding intensity modulation to plans with a uniform bolus, the HI could be improved (p = 0.017). The combination of a range-modulating bolus and intensity modulation provided a further significant improvement of the HI as compared to using intensity modulation in combination with a uniform bolus (p = 0.036). The range-modulating bolus also improved the CI compared to using a uniform bolus, both with an open beam (p = 0.046) and with intensity modulation (p = 0.018), as well as increased theD 98 % ${D_{98\% }}$ (p = 0.036 with open beam and p = 0.05 with intensity modulation) and reduced the medianD 2 % , Body - PTV ${D_{2\% ,{\mathrm{\ Body}} - {\mathrm{PTV}}}}$ (not significant). CONCLUSIONS By using intensity-modulated electron FLASH-RT in combination with range-modulating bolus, the target dose homogeneity and conformity in canine patients with simulated tumors in complex areas in the head-and-neck region could be improved. By utilizing this technique, we hope to decrease the dose outside the target volume and avoid hot spots in future clinical electron FLASH-RT studies, thereby reducing the risk of radiation-induced toxicity.
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Affiliation(s)
- Elise Konradsson
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Rebecka Ericsson Szecsenyi
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Gabriel Adrian
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Division of Oncology and Pathology, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Mizgin Coskun
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Betina Børresen
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Maja Louise Arendt
- Department of Veterinary Clinical Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Sven Åj Bäck
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Kristoffer Petersson
- Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Lund, Sweden
- Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Crister Ceberg
- Medical Radiation Physics, Department of Clinical Sciences, Lund University, Lund, Sweden
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12
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Maity I, Mostofi AA, Lischner J. Electrons Surf Phason Waves in Moiré Bilayers. Nano Lett 2023. [PMID: 37235740 DOI: 10.1021/acs.nanolett.3c00490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We investigate the effect of thermal fluctuations on the atomic and electronic structure of a twisted MoSe2/WSe2 heterobilayer using a combination of classical molecular dynamics and ab initio density functional theory calculations. Our calculations reveal that thermally excited phason modes give rise to an almost rigid motion of the moiré lattice. Electrons and holes in low-energy states are localized in specific stacking regions of the moiré unit cell and follow the thermal motion of these regions. In other words, charge carriers surf phason waves that are excited at finite temperatures. We also show that such surfing survives in the presence of a substrate and frozen potential. This effect has potential implications for the design of charge and exciton transport devices based on moiré materials.
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Affiliation(s)
- Indrajit Maity
- Departments of Materials and Physics and the Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, U.K
| | - Arash A Mostofi
- Departments of Materials and Physics and the Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, U.K
| | - Johannes Lischner
- Departments of Materials and Physics and the Thomas Young Centre for Theory and Simulation of Materials, Imperial College London, South Kensington Campus, London SW7 2AZ, U.K
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13
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Cooper CR, Jones DJL, Jones GDD, Petersson K. Comet Assay Profiling of FLASH-Induced Damage: Mechanistic Insights into the Effects of FLASH Irradiation. Int J Mol Sci 2023; 24:7195. [PMID: 37108360 PMCID: PMC10138874 DOI: 10.3390/ijms24087195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/06/2023] [Accepted: 04/10/2023] [Indexed: 04/29/2023] Open
Abstract
Numerous studies have demonstrated the normal tissue-sparing effects of ultra-high dose rate 'FLASH' irradiation in vivo, with an associated reduction in damage burden being reported in vitro. Towards this, two key radiochemical mechanisms have been proposed: radical-radical recombination (RRR) and transient oxygen depletion (TOD), with both being proposed to lead to reduced levels of induced damage. Previously, we reported that FLASH induces lower levels of DNA strand break damage in whole-blood peripheral blood lymphocytes (WB-PBL) ex vivo, but our study failed to distinguish the mechanism(s) involved. A potential outcome of RRR is the formation of crosslink damage (particularly, if any organic radicals recombine), whilst a possible outcome of TOD is a more anoxic profile of induced damage resulting from FLASH. Therefore, the aim of the current study was to profile FLASH-induced damage via the Comet assay, assessing any DNA crosslink formation as a putative marker of RRR and/or anoxic DNA damage formation as an indicative marker of TOD, to determine the extent to which either mechanism contributes to the "FLASH effect". Following FLASH irradiation, we see no evidence of any crosslink formation; however, FLASH irradiation induces a more anoxic profile of induced damage, supporting the TOD mechanism. Furthermore, treatment of WB-PBLs pre-irradiation with BSO abrogates the reduced strand break damage burden mediated by FLASH exposures. In summary, we do not see any experimental evidence to support the RRR mechanism contributing to the reduced damage burden induced by FLASH. However, the observation of a greater anoxic profile of damage following FLASH irradiation, together with the BSO abrogation of the reduced strand break damage burden mediated by FLASH, lends further support to TOD being a driver of the reduced damage burden plus a change in the damage profile mediated by FLASH.
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Affiliation(s)
- Christian R. Cooper
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
| | - Donald J. L. Jones
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
| | - George D. D. Jones
- Leicester Cancer Research Centre, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK; (D.J.L.J.); (G.D.D.J.)
| | - Kristoffer Petersson
- MRC Oxford Institute for Radiation Oncology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ, UK
- Department of Haematology, Oncology and Radiation Physics, Skåne University Hospital Lund University, 221 85 Lund, Sweden
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Balzanelli MG, Distratis P, Lazzaro R, Pham VH, Del Prete R, Mosca A, Inchingolo F, Aityan SK, Santacroce L, Nguyen KCD, Gargiulo Isacco C. From Pathogens to Cancer: Are Cancer Cells Evolved Mitochondrial Super Cells? Diagnostics (Basel) 2023; 13. [PMID: 36832301 DOI: 10.3390/diagnostics13040813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/07/2023] [Accepted: 02/19/2023] [Indexed: 02/23/2023] Open
Abstract
Life is based on a highly specific combination of atoms, metabolism, and genetics which eventually reflects the chemistry of the Universe which is composed of hydrogen, oxygen, nitrogen, sulfur, phosphorus, and carbon. The interaction of atomic, metabolic, and genetic cycles results in the organization and de-organization of chemical information of that which we consider as living entities, including cancer cells. In order to approach the problem of the origin of cancer it is therefore reasonable to start from the assumption that the sub-molecular level, the atomic structure, should be the considered starting point on which metabolism, genetics, and external insults eventually emanate. Second, it is crucial to characterize which of the entities and parts composing human cells may live a separate life; certainly, this theoretical standpoint would consider mitochondria, an organelle of "bacteria" origin embedded in conditions favorable for the onset of both. This organelle has not only been tolerated by immunity but has also been placed as a central regulator of cell defense. Virus, bacteria, and mitochondria are also similar in the light of genetic and metabolic elements; they share not only equivalent DNA and RNA features but also many basic biological activities. Thus, it is important to finalize that once the cellular integrity has been constantly broken down, the mitochondria like any other virus or bacteria return to their original autonomy to simply survive. The Warburg's law that states the ability of cancers to ferment glucose in the presence of oxygen, indicates mitochondria respiration abnormalities may be the underlying cause of this transformation towards super cancer cells. Though genetic events play a key part in altering biochemical metabolism, inducing aerobic glycolysis, this is not enough to impair mitochondrial function since mitochondrial biogenesis and quality control are constantly upregulated in cancers. While some cancers have mutations in the nuclear-encoded mitochondrial tricarboxylic acid (TCA) cycle, enzymes that produce oncogenic metabolites, there is also a bio-physic pathway for pathogenic mitochondrial genome mutations. The atomic level of all biological activities can be considered the very beginning, marked by the electron abnormal behavior that consequently affects DNA of both cells and mitochondria. Whilst the cell's nucleus DNA after a certain number of errors and defection tends to gradually switch off, the mitochondria DNA starts adopting several escape strategies, switching-on a few important genes that belong back at their original roots as independent beings. The ability to adopt this survival trick, by becoming completely immune to current life-threatening events, is probably the beginning of a differentiation process towards a "super-power cell", the cancer cells that remind many pathogens, including virus, bacteria, and fungi. Thus, here, we present a hypothesis regarding those changes that first begin at the mitochondria atomic level to steadily involve molecular, tissue and organ levels in response to the virus or bacteria constant insults that drive a mitochondria itself to become an "immortal cancer cell". Improved insights into this interplay between these pathogens and mitochondria progression may disclose newly epistemological paradigms as well as innovative procedures in targeting cancer cell progressive invasion.
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Abstract
The cardiovascular system requires iron to maintain its high energy demands and metabolic activity. Iron plays a critical role in oxygen transport and storage, mitochondrial function, and enzyme activity. However, excess iron is also cardiotoxic due to its ability to catalyze the formation of reactive oxygen species and promote oxidative damage. While mammalian cells have several redundant iron import mechanisms, they are equipped with a single iron-exporting protein, which makes the cardiovascular system particularly sensitive to iron overload. As a result, iron levels are tightly regulated at many levels to maintain homeostasis. Iron dysregulation ranges from iron deficiency to iron overload and is seen in many types of cardiovascular disease, including heart failure, myocardial infarction, anthracycline-induced cardiotoxicity, and Friedreich's ataxia. Recently, the use of intravenous iron therapy has been advocated in patients with heart failure and certain criteria for iron deficiency. Here, we provide an overview of systemic and cellular iron homeostasis in the context of cardiovascular physiology, iron deficiency, and iron overload in cardiovascular disease, current therapeutic strategies, and future perspectives.
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Affiliation(s)
- Konrad Teodor Sawicki
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University, Chicago, IL 60611
- Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Adam De Jesus
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University, Chicago, IL 60611
| | - Hossein Ardehali
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University, Chicago, IL 60611
- Division of Cardiology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
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Tereshchenko OE, Golyashov VA, Rusetsky VS, Kustov DA, Mironov AV, Demin AY. Vacuum Spin LED: First Step towards Vacuum Semiconductor Spintronics. Nanomaterials (Basel) 2023; 13:422. [PMID: 36770383 PMCID: PMC9919810 DOI: 10.3390/nano13030422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
Improving the efficiency of spin generation, injection, and detection remains a key challenge for semiconductor spintronics. Electrical injection and optical orientation are two methods of creating spin polarization in semiconductors, which traditionally require specially tailored p-n junctions, tunnel or Schottky barriers. Alternatively, we introduce here a novel concept for spin-polarized electron emission/injection combining the optocoupler principle based on vacuum spin-polarized light-emitting diode (spin VLED) making it possible to measure the free electron beam polarization injected into the III-V heterostructure with quantum wells (QWs) based on the detection of polarized cathodoluminescence (CL). To study the spin-dependent emission/injection, we developed spin VLEDs, which consist of a compact proximity-focused vacuum tube with a spin-polarized electron source (p-GaAs(Cs,O) or Na2KSb) and the spin detector (III-V heterostructure), both activated to a negative electron affinity (NEA) state. The coupling between the photon helicity and the spin angular momentum of the electrons in the photoemission and injection/detection processes is realized without using either magnetic material or a magnetic field. Spin-current detection efficiency in spin VLED is found to be 27% at room temperature. The created vacuum spin LED paves the way for optical generation and spin manipulation in the developing vacuum semiconductor spintronics.
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Affiliation(s)
- Oleg E. Tereshchenko
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Kol’tsovo 630559, Russia
| | - Vladimir A. Golyashov
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- Synchrotron Radiation Facility SKIF, Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Kol’tsovo 630559, Russia
| | - Vadim S. Rusetsky
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
- CJSC “Ekran FEP”, Novosibirsk 630060, Russia
| | - Danil A. Kustov
- Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk 630090, Russia
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Lebedev AA, Kozlovski VV, Davydovskaya KS, Kuzmin RA, Levinshtein ME, Strel’chuk AM. Features of the Carrier Concentration Determination during Irradiation of Wide-Gap Semiconductors: The Case Study of Silicon Carbide. Materials (Basel) 2022; 15:8637. [PMID: 36500133 PMCID: PMC9739460 DOI: 10.3390/ma15238637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/29/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
In this paper, the features of radiation compensation of wide-gap semiconductors are discussed, considering the case study of silicon carbide. Two classical methods of concentration determination are compared and analyzed: capacitance-voltage (C-V) and current-voltage (I-V) characteristics. The dependence of the base resistance in high-voltage 4H-SiC Schottky diodes on the dose of irradiation by electrons and protons is experimentally traced in the range of eight orders of magnitude. It is demonstrated that the dependence of the carrier concentration on the irradiation dose can be determined unambiguously and reliably in a very wide range of compensation levels, based on the results of measuring the I-V characteristics. It is shown that the determination of the carrier removal rate using the I-V characteristics is more correct than using the C-V characteristics, especially in the case of high radiation doses.
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Affiliation(s)
| | - Vitali V. Kozlovski
- Department of Experimental Physics, St. Petersburg State Polytechnic University, Polytekhnicheskaya 29, St. Petersburg 195251, Russia
| | | | - Roman A. Kuzmin
- Ioffe Institute, Politekhnicheskaya Street 26, St. Petersburg 194021, Russia
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Pfuhl T, Friedrich T, Scholz M. A double-strand-break model for the relative biological effectiveness of electrons based on ionization clustering. Med Phys 2022; 49:5562-5575. [PMID: 35686448 DOI: 10.1002/mp.15796] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND The effectiveness of ionizing radiation regarding DNA damage induction depends on its spatial energy deposition pattern. For electrons an increased effectiveness is observed at low kinetic energies due to the enhanced density of energy deposition events at electron track ends. PURPOSE A model is presented, which enables the calculation of the double-strand-break (DSB) yield and the relative biological effectiveness (RBE) for DSB induction of electrons. METHODS The model applies the mean free path between two ionizations and the assumption that two ionizations within a certain threshold distance are necessary to potentially lead to a DSB. Next to an expression for the electron RBE according to its common definition, a local RBE is determined, which describes the electrons' local effectiveness at a defined point on their track. RESULTS This local RBE allows a better understanding of microscopic processes resulting from radiation and can be used, for instance, to describe the mean effectiveness of the mixed electron radiation field as a function of the radial distance to the center of an ion track. CONCLUSIONS The presented model reflects the experimentally observed increased effectiveness of low-energetic electrons. It will be used in a future work to improve RBE predictions for ions performed with the local effect model.
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Affiliation(s)
- Tabea Pfuhl
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Thomas Friedrich
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
| | - Michael Scholz
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
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Bertolini S, Jacob T. Valence energy correction for electron reactive force field. J Comput Chem 2022; 43:870-878. [PMID: 35319099 DOI: 10.1002/jcc.26844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 02/19/2022] [Accepted: 03/02/2022] [Indexed: 11/07/2022]
Abstract
Reactive force fields (ReaxFF) are a classical method to describe material properties based on a bond-order formalism, that allows bond dissociation and consequently investigations of reactive systems. Semiclassical treatment of electrons was introduced within ReaxFF simulations, better known as electron reactive force fields (eReaxFF), to explicitly treat electrons as spherical Gaussian waves. In the original version of eReaxFF, the electrons and electron-holes can lead to changes in both the bond energy and the Coulomb energy of the system. In the present study, the method was modified to allow an electron to modify the valence energy, therefore, permitting that the electron's presence modifies the three-body interactions, affecting the angle among three atoms. When a reaction path involving electron transfer is more sensitive to the geometric configuration of the molecules, corrections in the angular structure in the presence of electrons become more relevant; in this case, bond dissociation may not be enough to describe a reaction path. Consequently, the application of the extended eReaxFF method developed in this work should provide an improved description of a reaction path. As a first demonstration this semiclassical force field was parametrized for hydrogen and oxygen interactions, including water and water's ions. With the modified methodology both the overall accuracy of the force field but also the description of the angles within the molecules in presence of electrons could be improved.
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Affiliation(s)
| | - Timo Jacob
- Institute of Electrochemistry, Ulm University, Ulm, Germany
- Helmholtz-Institute Ulm (HIU) Electrochemical Energy Storage, Ulm, Germany
- Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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Fastner G, Reitsamer R, Gaisberger C, Hitzl W, Urbański B, Murawa D, Matuschek C, Budach W, Ciabattoni A, Reiland J, Molnar M, Vidali C, Schumacher C, Sedlmayer F, On Behalf Of The Hiob Trialist Group. Hypofractionated Whole Breast Irradiation and Boost-IOERT in Early Stage Breast Cancer (HIOB): First Clinical Results of a Prospective Multicenter Trial (NCT01343459). Cancers (Basel) 2022; 14. [PMID: 35326548 DOI: 10.3390/cancers14061396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/03/2022] [Accepted: 03/06/2022] [Indexed: 02/05/2023] Open
Abstract
Background and purpose: To investigate intraoperative electron radiation therapy (IOERT) as a tumor bed boost during breast conserving surgery (BCS) followed by hypofractionated whole breast irradiation (HWBI) on age-correlated in-breast recurrence (IBR) rates in patients with low- to high-risk invasive breast cancer. Material and methods: BCS and IOERT (11.1 Gy) preceded a HWBI (40.5 Gy) in 15 fractions. Five-year IBR-rates were compared by a sequential ratio test (SQRT) with best evidences in three age groups (35−40 y and 41−50 y: 3.6%, >50 y: 2%) in a prospective single arm design. Null hypothesis (H0) was defined to undershoot these benchmarks for proof of superiority. Results: Of 1445 enrolled patients, 326 met exclusion criteria, leaving 1119 as eligible for analysis. After a median follow-up of 50 months (range 0.7−104), we detected two local recurrences, both in the age group >50 y. With no observed IBR, superiority was demonstrated for the patient groups 41−50 and >50 y, respectively. For the youngest group (35−40 y), no appropriate statistical evaluation was yet possible due to insufficient recruitment. Conclusions: In terms of five-year IBR-rates, Boost-IOERT followed by HWBI has been demonstrated to be superior in patients older than 50 and in the age group 41−50 when compared to best published evidence until 2010.
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Liew H, Mein S, Tessonnier T, Abdollahi A, Debus J, Dokic I, Mairani A. The Impact of Sub-Millisecond Damage Fixation Kinetics on the In Vitro Sparing Effect at Ultra-High Dose Rate in UNIVERSE. Int J Mol Sci 2022; 23:ijms23062954. [PMID: 35328377 PMCID: PMC8954991 DOI: 10.3390/ijms23062954] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/28/2022] [Accepted: 03/07/2022] [Indexed: 02/04/2023] Open
Abstract
The impact of the exact temporal pulse structure on the potential cell and tissue sparing of ultra-high dose-rate irradiation applied in FLASH studies has gained increasing attention. A previous version of our biophysical mechanistic model (UNIVERSE: UNIfied and VERSatile bio response Engine), based on the oxygen depletion hypothesis, has been extended in this work by considering oxygen-dependent damage fixation dynamics on the sub-milliseconds scale and introducing an explicit implementation of the temporal pulse structure. The model successfully reproduces in vitro experimental data on the fast kinetics of the oxygen effect in irradiated mammalian cells. The implemented changes result in a reduction in the assumed amount of oxygen depletion. Furthermore, its increase towards conventional dose-rates is parameterized based on experimental data from the literature. A recalculation of previous benchmarks shows that the model retains its predictive power, while the assumed amount of depleted oxygen approaches measured values. The updated UNIVERSE could be used to investigate the impact of different combinations of pulse structure parameters (e.g., dose per pulse, pulse frequency, number of pulses, etc.), thereby aiding the optimization of potential clinical application and the development of suitable accelerators.
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Affiliation(s)
- Hans Liew
- Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; (H.L.); (J.D.)
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
- Faculty of Physics and Astronomy, Heidelberg University, 69120 Heidelberg, Germany
| | - Stewart Mein
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
| | - Thomas Tessonnier
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
| | - Amir Abdollahi
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
| | - Jürgen Debus
- Clinical Cooperation Unit Radiation Oncology, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; (H.L.); (J.D.)
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
- Faculty of Physics and Astronomy, Heidelberg University, 69120 Heidelberg, Germany
| | - Ivana Dokic
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
| | - Andrea Mairani
- Division of Molecular and Translational Radiation Oncology, National Center for Tumor Diseases (NCT), Heidelberg University Hospital, 69120 Heidelberg, Germany; (S.M.); (A.A.); (I.D.)
- Heidelberg Institute of Radiation Oncology (HIRO), German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
- German Cancer Consortium (DKTK), 69120 Heidelberg, Germany
- Heidelberg Ion-Beam Therapy Center (HIT), 69120 Heidelberg, Germany;
- Correspondence: ; Tel.: +49-0-6221-56-37535
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22
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Curry A, White D, Cen Y. Small Molecule Regulators Targeting NAD + Biosynthetic Enzymes. Curr Med Chem 2022; 29:1718-1738. [PMID: 34060996 PMCID: PMC8630097 DOI: 10.2174/0929867328666210531144629] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 01/03/2023]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is a key player in many metabolic pathways as an activated carrier of electrons. In addition to being the cofactor for redox reactions, NAD+ also serves as the substrate for various enzymatic transformations such as adenylation and ADP-ribosylation. Maintaining cellular NAD+ homeostasis has been suggested as an effective anti-aging strategy. Given the importance of NAD+ in regulating a broad spectrum of cellular events, small molecules targeting NAD+ metabolism have been pursued as therapeutic interventions for the treatment of mitochondrial disorders and agerelated diseases. In this article, small molecule regulators of NAD+ biosynthetic enzymes will be reviewed. The focus will be given to the discovery and development of these molecules, the mechanism of action as well as their therapeutic potentials.
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Affiliation(s)
- Alyson Curry
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Dawanna White
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Yana Cen
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23219, USA;,Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA,Address correspondence to this author at the Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23219, USA; Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA; Tel: 804-828-7405;
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23
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Vukalović J, Maljković JB, Blanco F, García G, Predojević B, Marinković BP. Absolute Differential Cross-Sections for Elastic Electron Scattering from Sevoflurane Molecule in the Energy Range from 50-300 eV. Int J Mol Sci 2021; 23:21. [PMID: 35008454 PMCID: PMC8744708 DOI: 10.3390/ijms23010021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 12/12/2021] [Accepted: 12/15/2021] [Indexed: 12/04/2022] Open
Abstract
We report the results of the measurements and calculations of the absolute differential elastic electron scattering cross-sections (DCSs) from sevoflurane molecule (C4H3F7O). The experimental absolute DCSs for elastic electron scattering were obtained for the incident electron energies from 50 eV to 300 eV, and for scattering angles from 25° to 125° using a crossed electron/target beams setup and the relative flow technique for calibration to the absolute scale. For the calculations, we have used the IAM-SCAR+I method (independent atom model (IAM) applying the screened additivity rule (SCAR) with interference terms included (I)). The molecular cross-sections were obtained from the atomic data by using the SCAR procedure, incorporating interference term corrections, by summing all the relevant atomic amplitudes, including the phase coefficients. In this approach, we obtain the molecular differential scattering cross-section (DCS), which, integrated over the scattered electron angular range, gives the integral scattering cross-section (ICS). Calculated cross-sections agree very well with experimental results, in the whole energy and angular range.
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Affiliation(s)
- Jelena Vukalović
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
- Faculty of Science, University of Banja Luka, Mladena Stojanovića 2, 78000 Banja Luka, Republic of Srpska, Bosnia and Herzegovina;
| | - Jelena B. Maljković
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
| | - Francisco Blanco
- Departamento de Estructura de la Materia Física Térmica y Electrónica e IPARCOS, Universidad Complutense de Madrid, Plaza de Ciencias 1, 28040 Madrid, Spain;
| | - Gustavo García
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 113-bis, 28006 Madrid, Spain;
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Branko Predojević
- Faculty of Science, University of Banja Luka, Mladena Stojanovića 2, 78000 Banja Luka, Republic of Srpska, Bosnia and Herzegovina;
| | - Bratislav P. Marinković
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
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24
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Pettit JM, Randall CE, Peck ED, Harvey VL. A New MEPED-Based Precipitating Electron Data Set. J Geophys Res Space Phys 2021; 126:e2021JA029667. [PMID: 35865355 PMCID: PMC9286694 DOI: 10.1029/2021ja029667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 11/15/2021] [Accepted: 11/19/2021] [Indexed: 06/15/2023]
Abstract
The work presented here introduces a new data set for inclusion of energetic electron precipitation (EEP) in climate model simulations. Measurements made by the medium energy proton and electron detector (MEPED) instruments onboard both the Polar Orbiting Environmental Satellites and the European Space Agency Meteorological Operational satellites are used to create global maps of precipitating electron fluxes. Unlike most previous data sets, the electron fluxes are computed using both the 0° and 90° MEPED detectors. Conversion of observed, broadband electron count rates to differential spectral fluxes uses a linear combination of analytical functions instead of a single function. Two dimensional maps of electron spectral flux are created using Delaunay triangulation to account for the relatively sparse nature of the MEPED sampling. This improves on previous studies that use a 1D interpolation over magnetic local time or L-shell zonal averaging of the MEPED data. A Whole Atmosphere Community Climate Model (WACCM) simulation of the southern hemisphere 2003 winter using the new precipitating electron data set is shown to agree more closely with observations of odd nitrogen than WACCM simulations using other MEPED-based electron data sets. Simulated EEP-induced odd nitrogen increases led to ozone losses of more than 15% in the polar stratosphere near 10 hPa in September of 2003.
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Affiliation(s)
- Joshua M. Pettit
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
| | - Cora E. Randall
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
- Department of Atmospheric and Oceanic SciencesUniversity of ColoradoBoulderCOUSA
| | | | - V. Lynn Harvey
- Laboratory for Atmospheric and Space PhysicsUniversity of ColoradoBoulderCOUSA
- Department of Atmospheric and Oceanic SciencesUniversity of ColoradoBoulderCOUSA
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25
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Li D, Li L, Zhao M, Yang J, Wang Y, Xu X, Ge S, Fa W, Zheng Z. Exploring the activation pathway of photo-induced electrons in facets-dependent I -doped BiOCl nanosheets for PCPNa degradation. Nanotechnology 2021; 32:495707. [PMID: 34450603 DOI: 10.1088/1361-6528/ac21f3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Electrons can degrade pentachlorphenate sodium (PCPNa) directly or activate molecular oxygen to produce·O2-and ·OH for its degradation. However, less work has been performed to control such two kinds of reaction pathway by modifying BiOCl. Herein, we firstly regulated the reaction pathway between electrons and PCPNa by adjusting the amount of surface oxygen vacancies (OVs) and surface adsorbed hydroxyl groups in I-doped BiOCl exposed with different facets. OVs on (001) facets-exposed I-doped BiOCl enabled large amount of PCPNa to adsorb on its surface and facilitated the direct reaction between electrons and PCPNa. In contrary, more surface adsorbed hydroxyl groups and oxygen on (010) facets-exposed I-doped BiOCl can retard the direct reaction between electrons and PCPNa via lowering the adsorption of PCPNa and increasing the activation of molecular oxygen by electrons. Although more·O2-and ·OH generated in I-doped (010)-facets exposed BiOCl, I-doped (001)-facets exposed BiOCl exhibited better photocatalytic activity. We proposed that the direct reaction between electrons and PCPNa can enhance the utilization efficiency of photogenerated electrons and improve photocatalytic degradation efficiency of PCPNa.
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Affiliation(s)
- Dapeng Li
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Luqi Li
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Mingyue Zhao
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Jingming Yang
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Yafei Wang
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Xuefeng Xu
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Suxiang Ge
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Wenjun Fa
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
| | - Zhi Zheng
- Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province, Institute of Surface Micro and Nano Materials, College of Chemical and Materials Engineering, Xuchang University, Henan 461000, People's Republic of China
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26
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Grygier A, Skubacz K, Chałupnik S. The correction factors for UD802 dosimeters irradiated with different radiation energies and at different incidence angles. J Radiol Prot 2021; 41:526-538. [PMID: 33906175 DOI: 10.1088/1361-6498/abfbee] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
Many laboratories around the world work on the issue of protection against ionising radiation. It is a very broad topic, covering both the protection of members of the public and workers exposed to ionising radiation, based on personal or environmental monitoring. Thermoluminescence detectors are commonly used for this purpose, which is accepted in most countries. The entire process of dose evaluation with such dosimeters can be divided into several steps. Undoubtedly, one of the most important steps is the calibration procedure. The calibration should be performed in conditions as similar as possible to those experienced during the exposure. Moreover, the calibration is performed using only the Cs-137 source. This article presents results of Panasonic UD-802 irradiation dosimeters in different radiation fields generated by Cs-137, Kr-85, Sr-90/Y-90 and an x-ray tube, series N, and at different angles such as 0°, 30°, 60°, 90°. On the basis of the obtained results, the calibration coefficients and correction factors were determined in relation to calibration based on Cs-137 or Sr-90/Y-90 irradiated at 0°.
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Affiliation(s)
- Agata Grygier
- Silesian Center for Environmental Radioactivity, Central Mining Institute, Plac Gwarków1, 40166 Katowice
| | - Krystian Skubacz
- Silesian Center for Environmental Radioactivity, Central Mining Institute, Plac Gwarków1, 40166 Katowice
| | - Stanisław Chałupnik
- Silesian Center for Environmental Radioactivity, Central Mining Institute, Plac Gwarków1, 40166 Katowice
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27
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Tran VT, Cresti A. Thermoelectric properties of in-plane 90°-bent graphene nanoribbons with nanopores. Nanotechnology 2021; 32. [PMID: 34134103 DOI: 10.1088/1361-6528/ac0be7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/15/2021] [Indexed: 06/12/2023]
Abstract
We study the thermoelectric performance of 90°-bent graphene nanoribbons containing nanopores for optimized design of multiple functional circuits including thermoelectric generators. We show that the thermal conductance of the 90°-bent ribbons is lower from few times to an order of magnitude compared to that of pristine armchair and zigzag straight ribbons. Consequently, the thermoelectric performance of the bent ribbons is better than its straight ribbon counterparts, in particular at high temperatures above 500 K. More importantly, the introduction of nanopores is demonstrated to strongly enhance their thermoelectric capacity. At 500 K, the figure of meritZTincreases by more than 160% (from 0.39 without pores to 0.64) with 3 nanopores incorporated, and by more than 200% (up to 0.88) when 24 nanopores are introduced.ZT≈1 can be achieved at a temperature of about 1000 K. In addition, the thermoelectric performance is shown to be further improved by adopting asymmetrical leads. This study demonstrates that 90°-bent ribbons with nanopores have decent thermoelectric performance for a wide range of temperatures and may find application as efficient thermoelectric converters.
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Affiliation(s)
- Van-Truong Tran
- IMPMC, Université Pierre et Marie Curie (UPMC), Sorbonne Universités, F-75252 Paris Cedex 05, France
| | - Alessandro Cresti
- Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, Grenoble INP, IMEP-LAHC, F-38000 Grenoble, France
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28
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Helliwell JR. Combining X-rays, neutrons and electrons, and NMR, for precision and accuracy in structure-function studies. Acta Crystallogr A Found Adv 2021; 77:173-185. [PMID: 33944796 PMCID: PMC8127390 DOI: 10.1107/s205327332100317x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 03/25/2021] [Indexed: 02/02/2023] Open
Abstract
The distinctive features of the physics-based probes used in understanding the structure of matter focusing on biological sciences, but not exclusively, are described in the modern context. This is set in a wider scope of holistic biology and the scepticism about `reductionism', what is called the `molecular level', and how to respond constructively. These topics will be set alongside the principles of accuracy and precision, and their boundaries. The combination of probes and their application together is the usual way of realizing accuracy. The distinction between precision and accuracy can be blurred by the predictive force of a precise structure, thereby lending confidence in its potential accuracy. These descriptions will be applied to the comparison of cryo and room-temperature protein crystal structures as well as the solid state of a crystal and the same molecules studied by small-angle X-ray scattering in solution and by electron microscopy on a sample grid. Examples will include: time-resolved X-ray Laue crystallography of an enzyme Michaelis complex formed directly in a crystal equivalent to in vivo; a new iodoplatin for radiation therapy predicted from studies of platin crystal structures; and the field of colouration of carotenoids, as an effective assay of function, i.e. their colouration, when unbound and bound to a protein. The complementarity of probes, as well as their combinatory use, is then at the foundation of real (biologically relevant), probe-artefacts-free, structure-function studies. The foundations of our methodologies are being transformed by colossal improvements in technologies of X-ray and neutron sources and their beamline instruments, as well as improved electron microscopes and NMR spectrometers. The success of protein structure prediction from gene sequence recently reported by CASP14 also opens new doors to change and extend the foundations of the structural sciences.
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Affiliation(s)
- John R. Helliwell
- Department of Chemistry, University of Manchester, Manchester, M13 9PL, United Kingdom
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29
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Fadavi P, Nafissi N, Mahdavi SR, Jafarnejadi B, Javadinia SA. Outcome of hypofractionated breast irradiation and intraoperative electron boost in early breast cancer: A randomized non-inferiority clinical trial. Cancer Rep (Hoboken) 2021; 4:e1376. [PMID: 33797199 PMCID: PMC8552001 DOI: 10.1002/cnr2.1376] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 02/03/2021] [Accepted: 03/03/2021] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Intraoperative electron radiotherapy (IOERT) followed by hypofractionated whole breast irradiation (HWBI) provides the shortest possible time of adjuvant breast irradiation. The efficacy of either method has been described in previous reports; however, to our knowledge, the efficacy of combined therapy has not been reported. AIM To compare the toxicity and cosmetic outcome of IOERT as a tumor bed boost followed by HWBI with conventional whole breast irradiation (CWBI) followed by external electron tumor bed boost (EETBB) after breast conserving surgery (BCS) in patients with invasive breast cancer. METHODS In 2019, a prospective noninferiority trial (IRCT20180919041070N2) was started. After BCS, early-stage breast cancer patients were treated by IOERT (10 Gy) and HWBI (42.56 Gy in 16 fractions) or CWBI (50 Gy in 25 fraction) and EETBB (10 Gy in 5) in a double-arm design. Acute/late toxicity and cosmetic outcome were evaluated by common toxicity criteria (CTC) after 1-year follow-up (FUP) at the level of p < .05. RESULTS Of 60 eligible patients, 30 were allocated to each group. Regarding acute effects after a median FUP of 12 months, CTC-score of grade II-III erythema (p = .001) and desquamation (p = .005) were significantly higher in CWBI+EETBB compared to IOERT+ HWBI. However, there were no significant differences at the end of radiotherapy and after 1 month, 6 months, and 1 year. Cosmetic outcome after radiation was similar in both groups mostly rating as good/excellent after 1-year FUP. CONCLUSIONS Boost-IOERT/HWBI regimen has comparable acute and late treatment toxicity profiles compared to the CWBI.
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Affiliation(s)
- Pedram Fadavi
- Department of Radiation Oncology, Iran University of Medical Sciences, Tehran, Iran
| | - Nahid Nafissi
- Department of General Surgery, Iran University of Medical Sciences, Tehran, Iran
| | - Seied Rabi Mahdavi
- Department of Medical Physics, Iran University of Medical Sciences, Tehran, Iran
| | - Bahareh Jafarnejadi
- Department of Radiation Oncology, Iran University of Medical Sciences, Tehran, Iran
| | - Seyed Alireza Javadinia
- Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran
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30
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Vukalović J, Maljković JB, Tökési K, Predojević B, Marinković BP. Elastic Electron Scattering from Methane Molecule in the Energy Range from 50-300 eV. Int J Mol Sci 2021; 22:E647. [PMID: 33440715 PMCID: PMC7826858 DOI: 10.3390/ijms22020647] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/30/2020] [Accepted: 01/01/2021] [Indexed: 11/23/2022] Open
Abstract
Electron interaction with methane molecule and accurate determination of its elastic cross-section is a demanding task for both experimental and theoretical standpoints and relevant for our better understanding of the processes in Earth's and Solar outer planet atmospheres, the greenhouse effect or in plasma physics applications like vapor deposition, complex plasma-wall interactions and edge plasma regions of Tokamak. Methane can serve as a test molecule for advancing novel electron-molecule collision theories. We present a combined experimental and theoretical study of the elastic electron differential cross-section from methane molecule, as well as integral and momentum transfer cross-sections in the intermediate energy range (50-300 eV). The experimental setup, based on a crossed beam technique, comprising of an electron gun, a single capillary gas needle and detection system with a channeltron is used in the measurements. The absolute values for cross-sections are obtained by relative-flow method, using argon as a reference. Theoretical results are acquired using two approximations: simple sum of individual atomic cross-sections and the other with molecular effect taken into the account.
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Affiliation(s)
- Jelena Vukalović
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
- Faculty of Science, University of Banja Luka, Mladena Stojanovića 2, 78000 Banja Luka, Republic of Srpska, Bosnia and Herzegovina;
| | - Jelena B. Maljković
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
| | - Karoly Tökési
- Institute for Nuclear Research (ATOMKI), 4026 Debrecen, Hungary;
| | - Branko Predojević
- Faculty of Science, University of Banja Luka, Mladena Stojanovića 2, 78000 Banja Luka, Republic of Srpska, Bosnia and Herzegovina;
| | - Bratislav P. Marinković
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia; (J.V.); (J.B.M.)
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31
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Ozkan Loch C, Eichenberger MA, Togno M, Zinsli SP, Egloff M, Papa A, Ischebeck R, Lomax AJ, Peier P, Safai S. Characterization of a Low-Cost Plastic Fiber Array Detector for Proton Beam Dosimetry. Sensors (Basel) 2020; 20:s20205727. [PMID: 33050153 PMCID: PMC7601306 DOI: 10.3390/s20205727] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/21/2020] [Accepted: 09/28/2020] [Indexed: 01/12/2023]
Abstract
The Pencil Beam Scanning (PBS) technique in proton therapy uses fast magnets to scan the tumor volume rapidly. Changing the proton energy allows changing to layers in the third dimension, hence scanning the same volume several times. The PBS approach permits adapting the speed and/or current to modulate the delivered dose. We built a simple prototype that measures the dose distribution in a single step. The active detection material consists of a single layer of scintillating fibers (i.e., 1D) with an active length of 100 mm, a width of 18.25 mm, and an insignificant space (20 μm) between them. A commercial CMOS-based camera detects the scintillation light. Short exposure times allow running the camera at high frame rates, thus, monitoring the beam motion. A simple image processing method extracts the dose information from each fiber of the array. The prototype would allow scaling the concept to multiple layers read out by the same camera, such that the costs do not scale with the dimensions of the fiber array. Presented here are the characteristics of the prototype, studied under two modalities: spatial resolution, linearity, and energy dependence, characterized at the Center for Proton Therapy (Paul Scherrer Institute); the dose rate response, measured at an electron accelerator (Swiss Federal Institute of Metrology).
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Affiliation(s)
- Cigdem Ozkan Loch
- Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.A.E.); (S.P.Z.); (R.I.)
- Correspondence:
| | - Michael Alexander Eichenberger
- Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.A.E.); (S.P.Z.); (R.I.)
| | - Michele Togno
- Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.T.); (M.E.); (A.J.L.); (S.S.)
| | - Simon Pascal Zinsli
- Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.A.E.); (S.P.Z.); (R.I.)
| | - Martina Egloff
- Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.T.); (M.E.); (A.J.L.); (S.S.)
| | - Angela Papa
- Department for Research with Neutrons and Muons, Paul Scherrer Institut, 5232 Villigen, Switzerland;
| | - Rasmus Ischebeck
- Department of Large Scale Research Facilities, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.A.E.); (S.P.Z.); (R.I.)
| | - Antony John Lomax
- Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.T.); (M.E.); (A.J.L.); (S.S.)
| | - Peter Peier
- Laboratory Ionising Radiation, Federal Institute of Metrology (METAS), 3003 Bern-Wabern, Switzerland;
| | - Sairos Safai
- Center for Proton Therapy, Paul Scherrer Institut, 5232 Villigen, Switzerland; (M.T.); (M.E.); (A.J.L.); (S.S.)
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32
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Helliwell JR. What is the structural chemistry of the living organism at its temperature and pressure? Acta Crystallogr D Struct Biol 2020; 76:87-93. [PMID: 32038039 PMCID: PMC7008516 DOI: 10.1107/s2059798320000546] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/15/2020] [Indexed: 12/02/2022] Open
Abstract
The three probes of the structure of matter (X-rays, neutrons and electrons) in biology have complementary properties and strengths. The balance between these three probes within their strengths and weaknesses is perceived to change, even dramatically so at times. For the study of combined states of order and disorder, NMR crystallography is also applicable. Of course, to understand biological systems the required perspectives are surely physiologically relevant temperatures and relevant chemical conditions, as well as a minimal perturbation owing to the needs of the probe itself. These remain very tough challenges because, for example, cryoEM by its very nature will never be performed at room temperature, crystallization often requires nonphysiological chemical conditions, and X-rays and electrons cause beam damage. However, integrated structural biology techniques and functional assays provide a package towards physiological relevance of any given study. Reporting of protein crystal structures, and their associated database entries, could usefully indicate how close to the biological situation they are, as discussed in detail in this feature article.
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Affiliation(s)
- John R. Helliwell
- Department of Chemistry, University of Manchester, Manchester M13 9PL, England
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33
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Anusionwu PC, Alpuche Aviles JE, Pistorius S. The use of 0.5r cav as an effective point of measurement for cylindrical chambers may result in a systematic shift of electron percentage depth doses. J Appl Clin Med Phys 2020; 21:117-126. [PMID: 31898872 PMCID: PMC6964751 DOI: 10.1002/acm2.12797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 10/29/2019] [Accepted: 11/22/2019] [Indexed: 11/29/2022] Open
Abstract
Electron dosimetry can be performed using cylindrical chambers, plane‐parallel chambers, and diode detectors. The finite volume of these detectors results in a displacement effect which is taken into account using an effective point of measurement (EPOM). Dosimetry protocols have recommended a shift of 0.5 rcav for cylindrical chambers; however, various studies have shown that the optimal shift may deviate from this recommended value. This study investigated the effect that the selection of EPOM shift for cylindrical chamber has on percentage depth dose (PDD) curves. Depth dose curves were measured in a water phantom for electron beams with energies ranging from 6 to 18 MeV. The detectors investigated were of three different types: diodes (Diode‐E PTW 60017 and SFD IBA), cylindrical (Semiflex PTW 31010, PinPoint PTW 31015, and A12 Exradin), and parallel plate ionization chambers (Advanced Markus PTW 34045 and Markus PTW 23343). Depth dose curves measured with Diode‐E and Advanced Markus agreed within 0.2 mm at R50 except for 18 MeV and extremely large field size. The PDDs measured with the Semiflex chamber and Exradin A12 were about 1.1 mm (with respect to the Advanced Markus chamber) shallower than those measured with the other detectors using a 0.5 rcav shift. The difference between the PDDs decreased when a Pinpoint chamber, with a smaller cavity radius, was used. Agreement improved at lower energies, with the use of previously published EPOM corrections (0.3 rcav). Therefore, the use of 0.5 rcav as an EPOM may result in a systematic shift of the therapeutic portion of the PDD (distances < R90). Our results suggest that a 0.1 rcav shift is more appropriate for one chamber model (Semiflex PTW 31010).
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Affiliation(s)
- Princess C Anusionwu
- CancerCare Manitoba, Winnipeg, Canada.,Department of Physics & Astronomy, University of Manitoba, Winnipeg, Canada
| | - Jorge E Alpuche Aviles
- CancerCare Manitoba, Winnipeg, Canada.,Department of Physics & Astronomy, University of Manitoba, Winnipeg, Canada.,Department of Radiology, University of Manitoba, Winnipeg, Canada
| | - Stephen Pistorius
- CancerCare Manitoba, Winnipeg, Canada.,Department of Physics & Astronomy, University of Manitoba, Winnipeg, Canada.,Department of Radiology, University of Manitoba, Winnipeg, Canada
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34
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Zhang Z, Meng X, Cui W, Ahmad SS, Kamal MA, Zhang J. NMR: From Molecular Mechanism to its Application in Medical Care. Med Chem 2019; 16:1089-1098. [PMID: 31713489 DOI: 10.2174/1573406415666191111141630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/03/2019] [Accepted: 10/06/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Nuclear Magnetic Resonance (NMR) spectroscopy is a systematic science strategy utilized in pharmaceutical research, development, quality control, and research to decide the content and purity of a sample as well as its sub-atomic structure. There are several parameters working for better execution of NMR which can include chemical shifts, spin multiplicity, pH dependence, heteronuclear and homonuclear covalent network, and the atomic overhauser impact. NMR imaging offers an extensive scope of potential outcomes for the portrayal of skeletal muscle structure, function and metabolism. 1H additionally has the most noteworthy NMR affectability of any nucleus. The principle of NMR depends on the spins of atomic nuclei. The magnetic estimations rely on an unpaired electron, while NMR estimates attractive impact brought about by the turn of protons and neutrons. The nucleons have intrinsic angular momenta or spins, which is considered as basic magnet. CONCLUSION The presence of atomic attraction was uncovered in the hyperfine structure of spectral lines. If the nucleus magnetic moment is put in the magnetic field, the phenomenon of space quantization can be observed and each allowed direction will have a marginally unique energy level. Invitro, high-resolution NMR spectroscopy helps to assess tumor metabolism by the investigation of body liquids like urine, blood and removed tissue specimens. In-cell NMR is a powerful technique to assess strong compounds in medication improvement to spare exploratory expenses.
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Affiliation(s)
- Zhenhong Zhang
- Department of Radiological, Dezhou People's Hospital of Shandong Province, No. 1751, New Lake Avenue, 253014,
P.R. China
| | - Xiaohong Meng
- Department of Radiological, Dezhou People's Hospital of Shandong Province, No. 1751, New Lake Avenue, 253014,
P.R. China
| | - Wei Cui
- Department of Radiological, Dezhou People's Hospital of Shandong Province, No. 1751, New Lake Avenue, 253014,
P.R. China
| | - Syed S Ahmad
- Department of Bioengineering, Faculty of Engineering, Integral University, Lucknow, India
| | - Mohammad A Kamal
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah 21589, Kingdom of Saudi Arabia,Enzymoics, 7 Peterlee Place, Hebersham, NSW 2770, Australia; 5Novel Global Community Educational Foundation,
Australia
| | - Jinguo Zhang
- Department of Radiological, Dezhou People's Hospital of Shandong Province, No. 1751, New Lake Avenue, 253014,
P.R. China
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35
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D'Arcy R, Aschikhin A, Bohlen S, Boyle G, Brümmer T, Chappell J, Diederichs S, Foster B, Garland MJ, Goldberg L, Gonzalez P, Karstensen S, Knetsch A, Kuang P, Libov V, Ludwig K, Martinez de la Ossa A, Marutzky F, Meisel M, Mehrling TJ, Niknejadi P, Põder K, Pourmoussavi P, Quast M, Röckemann JH, Schaper L, Schmidt B, Schröder S, Schwinkendorf JP, Sheeran B, Tauscher G, Wesch S, Wing M, Winkler P, Zeng M, Osterhoff J. FLASHForward: plasma wakefield accelerator science for high-average-power applications. Philos Trans A Math Phys Eng Sci 2019; 377:20180392. [PMID: 31230573 PMCID: PMC6602913 DOI: 10.1098/rsta.2018.0392] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 04/30/2019] [Indexed: 06/09/2023]
Abstract
The FLASHForward experimental facility is a high-performance test-bed for precision plasma wakefield research, aiming to accelerate high-quality electron beams to GeV-levels in a few centimetres of ionized gas. The plasma is created by ionizing gas in a gas cell either by a high-voltage discharge or a high-intensity laser pulse. The electrons to be accelerated will either be injected internally from the plasma background or externally from the FLASH superconducting RF front end. In both cases, the wakefield will be driven by electron beams provided by the FLASH gun and linac modules operating with a 10 Hz macro-pulse structure, generating 1.25 GeV, 1 nC electron bunches at up to 3 MHz micro-pulse repetition rates. At full capacity, this FLASH bunch-train structure corresponds to 30 kW of average power, orders of magnitude higher than drivers available to other state-of-the-art LWFA and PWFA experiments. This high-power functionality means FLASHForward is the only plasma wakefield facility in the world with the immediate capability to develop, explore and benchmark high-average-power plasma wakefield research essential for next-generation facilities. The operational parameters and technical highlights of the experiment are discussed, as well as the scientific goals and high-average-power outlook. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.
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Affiliation(s)
- R. D'Arcy
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - A. Aschikhin
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - S. Bohlen
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - G. Boyle
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - T. Brümmer
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - J. Chappell
- University College London, Gower Street, London WC1E 6BT, UK
| | - S. Diederichs
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - B. Foster
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- University of Oxford, Wellington Square, Oxford OX1 2JD, UK
| | - M. J. Garland
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - L. Goldberg
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - P. Gonzalez
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - S. Karstensen
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - A. Knetsch
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - P. Kuang
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - V. Libov
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - K. Ludwig
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - A. Martinez de la Ossa
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - F. Marutzky
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - M. Meisel
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - T. J. Mehrling
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA
| | - P. Niknejadi
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - K. Põder
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - P. Pourmoussavi
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - M. Quast
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - J. -H. Röckemann
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - L. Schaper
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - B. Schmidt
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - S. Schröder
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - J. -P. Schwinkendorf
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - B. Sheeran
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - G. Tauscher
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - S. Wesch
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - M. Wing
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- University College London, Gower Street, London WC1E 6BT, UK
| | - P. Winkler
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
- Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - M. Zeng
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - J. Osterhoff
- Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
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König L, Lang K, Heil J, Golatta M, Major G, Krug D, Hörner-Rieber J, Häfner MF, Koerber SA, Harrabi S, Bostel T, Debus J, Uhl M. Acute Toxicity and Early Oncological Outcomes After Intraoperative Electron Radiotherapy (IOERT) as Boost Followed by Whole Breast Irradiation in 157 Early Stage Breast Cancer Patients-First Clinical Results From a Single Center. Front Oncol 2019; 9:384. [PMID: 31165041 PMCID: PMC6536702 DOI: 10.3389/fonc.2019.00384] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 04/24/2019] [Indexed: 11/13/2022] Open
Abstract
Introduction: Breast conserving surgery (BCS) followed by postoperative whole breast irradiation (WBI) is the current standard of care for early stage breast cancer patients. Boost to the tumor bed is recommended for patients with a higher risk of local recurrence and may be applied with different techniques. Intraoperative electron radiotherapy (IOERT) offers several advantages compared to other techniques, like direct visualization of the tumor bed, better skin sparing, less inter- and intrafractional motion, but also radiobiological effects may be beneficial. Objective of this retrospective analysis of IOERT as boost in breast cancer patients was to assess acute toxicity and early oncological outcomes. Material and Methods: All patients, who have been irradiated between 11/2014 and 01/2018 with IOERT during BCS were analyzed. IOERT was applied using the mobile linear accelerator Mobetron with a total dose of 10 Gy, prescribed to the 90% isodose. After ensured woundhealing, WBI followed with normofractionated or hypofractionated regimens. Patient reports, including diagnostic examinations and toxicity were analyzed after surgery and 6-8 weeks after WBI. Overall survival, distant progression-free survival, in-breast and contralateral breast local progression-free survival were calculated using the Kaplan-Meier method. Furthermore, recurrence patterns were assessed. Results: In total, 157 patients with a median age of 57 years were evaluated. Postoperative adverse events were mild with seroma and hematoma grade 1-2 in 26% and grade 3 in 0.6% of the patients. Wound infections grade 2-3 occurred in 2.2% and wound dehiscence grade 1-2 in 1.9% of the patients. Six to eight weeks after WBI radiotherapy-dependent acute dermatitis grade 1-2 was most common in 90.9% of the patients. Only 4.6% of the patients suffered from dermatitis grade 3. No grade 4 toxicities were documented after surgery or WBI. 2- and 3-year overall survival and distant progression-free survival, were 97.5 and 93.6, and 0.7 and 2.8%, respectively. In-breast recurrence and contralateral breast cancer rates after 3 years were 1.9 and 2.8%, respectively. Conclusion: IOERT boost during BCS is a safe treatment option with low acute toxicity. Short-term recurrence rates are comparable to previously published data and emphasize, that IOERT as boost is an effective treatment.
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Affiliation(s)
- Laila König
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Kristin Lang
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Jörg Heil
- Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany
| | - Michael Golatta
- Department of Gynecology and Obstetrics, University Hospital Heidelberg, Heidelberg, Germany
| | - Gerald Major
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - David Krug
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Schleswig Holstein, Kiel, Germany
| | - Juliane Hörner-Rieber
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Matthias F Häfner
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Stefan A Koerber
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Semi Harrabi
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Tilman Bostel
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Mainz, Mainz, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
| | - Matthias Uhl
- Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany.,Heidelberg Institute of Radiation Oncology (HIRO), Heidelberg, Germany
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37
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Martell K, Poirier Y, Zhang T, Hudson A, Spencer D, Jacso F, Hayashi R, Banerjee R, Khan R, Wolfe N, Voroney JP. Radiation therapy for deep periocular cancer treatments when protons are unavailable: is combining electrons and orthovoltage therapy beneficial? J Radiat Res 2018; 59:593-603. [PMID: 30053071 PMCID: PMC6151628 DOI: 10.1093/jrr/rry045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 01/31/2018] [Indexed: 06/08/2023]
Abstract
Deep periocular cancers can be difficult to plan and treat with radiation, given the difficulties in apposing bolus to skin, and the proximity to the retina and other optic structures. We sought to compare the combination of electrons and orthovoltage therapy (OBE) with existing modalities for these lesions. Four cases-a retro-orbital melanoma (Case 1) and basal cell carcinomas, extending across the eyelid (Case 2) or along the medial canthus (Cases 3-4)-were selected for comparison. In each case, radiotherapy plans for electron only, 70% electron and 30% orthovoltage (OBE), volumetric-modulated arc therapy (VMAT), conformal arc, and protons were compared. Dose-volume histograms for planning target volume coverage and selected organs at risk (OARs) were then calculated. The V90% coverage of the planning target volume was >98% for electrons, VMAT, conformal arc and proton plans and 90.2% and 89.5% in OBE plans for Cases 2 and 3, respectively. The retinal V80% was >98% in electron, VMAT and proton plans and 79.4%; and 87.1% in OBE and conformal arcs for Case 2 and 91.3%, 36.4%, 56.9%, 52.4% and 43.7% for Case 3 in electrons, OBE, VMAT, conformal arc and proton plans, respectively. Protons provided superior coverage, homogeneity and OAR sparing, compared with all other modalities. However, given its simplicity and widespread availability, OBE is a potential alternative treatment option for moderately deep lesions where bolus placement is difficult.
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Affiliation(s)
- Kevin Martell
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Yannick Poirier
- Department of Radiation Oncology, University of Maryland, 22 S Greene St, Baltimore, MD, USA
| | - Tiezhi Zhang
- Department of Radiation Oncology, Washington University in St. Louis, 660 S. Euclid Ave., CB, St. Louis, MO, USA
| | - Alana Hudson
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - David Spencer
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Ferenc Jacso
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Richard Hayashi
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Robyn Banerjee
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Rao Khan
- Department of Radiation Oncology, Washington University in St. Louis, 660 S. Euclid Ave., CB, St. Louis, MO, USA
| | - Nathan Wolfe
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
| | - Jon-Paul Voroney
- Department of Oncology, University of Calgary, Tom Baker Cancer Centre 1331 29 Street Northwest, Calgary, Alberta, Canada
- Calgary Zone, Alberta Health Services, Foothills Medical Centre, 1331-29 ST NW, Calgary, Alberta, Canada
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38
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Geesink JH, Meijer DKF. Bio-soliton model that predicts non-thermal electromagnetic frequency bands, that either stabilize or destabilize living cells. Electromagn Biol Med 2018; 36:357-378. [PMID: 29164985 DOI: 10.1080/15368378.2017.1389752] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Solitons, as self-reinforcing solitary waves, interact with complex biological phenomena such as cellular self-organization. A soliton model is able to describe a spectrum of electromagnetism modalities that can be applied to understand the physical principles of biological effects in living cells, as caused by endogenous and exogenous electromagnetic fields and is compatible with quantum coherence. A bio-soliton model is proposed, that enables to predict which eigen-frequencies of non-thermal electromagnetic waves are life-sustaining and which are, in contrast, detrimental for living cells. The particular effects are exerted by a range of electromagnetic wave eigen-frequencies of one-tenth of a Hertz till Peta Hertz that show a pattern of 12 bands, and can be positioned on an acoustic reference frequency scale. The model was substantiated by a meta-analysis of 240 published articles of biological electromagnetic experiments, in which a spectrum of non-thermal electromagnetic waves were exposed to living cells and intact organisms. These data support the concept of coherent quantized electromagnetic states in living organisms and the theories of Fröhlich, Davydov and Pang. It is envisioned that a rational control of shape by soliton-waves and related to a morphogenetic field and parametric resonance provides positional information and cues to regulate organism-wide systems properties like anatomy, control of reproduction and repair.
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Affiliation(s)
- J H Geesink
- a Department of biophysics , Groningen , The Netherlands
| | - D K F Meijer
- a Department of biophysics , Groningen , The Netherlands
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Satoskar AA, Suleiman S, Ayoub I, Hemminger J, Parikh S, Brodsky SV, Bott C, Calomeni E, Nadasdy GM, Rovin B, Hebert L, Nadasdy T. Staphylococcus Infection-Associated GN - Spectrum of IgA Staining and Prevalence of ANCA in a Single-Center Cohort. Clin J Am Soc Nephrol 2017; 12:39-49. [PMID: 27821389 PMCID: PMC5220658 DOI: 10.2215/cjn.05070516] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 09/15/2016] [Indexed: 01/25/2023]
Abstract
BACKGROUND AND OBJECTIVES Staphylococcus infection-associated GN (SAGN) is a well recognized disease entity, particularly because of the frequent IgA-dominant glomerular immunoglobulin staining on kidney biopsy. Biopsy features can resemble two other disease entities - primary IgA nephropathy and Henoch-Schönlein purpura nephritis - posing a diagnostic pitfall. This is clinically relevant because of the crucial difference in the therapeutic approach. The diagnosis of SAGN is further complicated by the variability in the degree of glomerular IgA (and C3) staining, the extent of electron dense immune-type deposits, and positive ANCA serology in some patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We performed a thorough histopathologic review of our single-center cohort of 78 culture-proven SAGN biopsies to assess the spectrum of IgA staining, prevalence of ANCA serology, prevalence of subepithelial "humps," and other histologic features to distinguish from primary IgA nephropathy. RESULTS Among the 78 SAGN biopsies, IgA staining was trace in 25%, mild in 19%, moderate in 44%, and strong in 12% of the cases. C3 was frequently moderate-to-strong but was trace in 14% of the biopsies. Concomitantly trace IgA, IgG, and C3 (pauci-immune pattern) was seen in 13%. Crescents were present in 35% of the SAGN biopsies. Out of 41 patients tested for ANCA, nine (22%) were positive, including patients with endocarditis and other infections. Subepithelial humps were identified in only 31% of the SAGN biopsies. CONCLUSIONS SAGN biopsies show marked variability in IgA immunofluorescence staining and low frequency of subepithelial humps compared with poststreptococcal GN. Occasional ANCA positivity is present in cases of SAGN, even in infections other than endocarditis. Therefore, biopsy diagnosis can be difficult particularly when clinical symptoms of infection are subtle. Both the pathologist and the nephrologist should be aware of these diagnostic pitfalls.
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Affiliation(s)
| | | | - Isabelle Ayoub
- Department of Internal Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio
| | | | - Samir Parikh
- Department of Internal Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio
| | | | | | | | | | - Brad Rovin
- Department of Internal Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Lee Hebert
- Department of Internal Medicine, Division of Nephrology, Ohio State University Wexner Medical Center, Columbus, Ohio
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Juran CM, Dolwick MF, McFetridge PS. Mechanobiological Assessment of TMJ Disc Surfaces: Nanoindentation and Transmission Electron Microscopy. J Oral Maxillofac Res 2016; 6:e3. [PMID: 26904180 PMCID: PMC4761433 DOI: 10.5037/jomr.2015.6403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2015] [Accepted: 12/14/2015] [Indexed: 11/23/2022]
Abstract
Objectives Temporomandibular disc is a mechanically robust fibrocartilage tissue exhibiting highly elastic compressive, shear, and tensile moduli with structurally dense extracellular matrix that supports functional loading of the joint. The aim of this study was to illustrate structural complexities of the superior and inferior disc surfaces, to demonstrate the robust mechanical ability of the disc as a whole may be due to depth-dependent regional/layered variation, and also to provide characterization data imperative for future tissue engineering efforts focused on restoring function to the joint. Material and Methods Nanoindentation was used to assess tissue zones in conjunction with detailed Transmission Electron Microscopy to define structural attributes that influence the temporomandibular disc function. Results The disc architecture adjacent to the superior surface was shown to have three distinct regional segments within the interface layer: 1-a surface peripheral layer; 2-subsurface region; and 3-a layer of helical matrix bundles. The inferior surface displayed an interface layer (20 µm) that showed limited cell populations with little depth-dependent structural variation, a stiffer elastic modulus and reduced energy dissipation compared to the superior surface. These data indicate that the primary function of the inferior surface is resistance to compression rather than load distribution during joint motion. Conclusions These are the first works that demonstrate that the superior central surface of the he temporomandibular disc is structured in depth-dependent isometric layers, each of which provides different mechanical function supporting the bulk tissue’s properties. From a clinical perspective these data have potential to define regions susceptible to fatigue that may translate to diagnostic criteria to better define the stages of dysfunction.
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Affiliation(s)
- Cassandra M Juran
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida United States
| | - M Franklin Dolwick
- Division of Oral and Maxillofacial Surgery, College of Dentistry, University of Florida United States
| | - Peter S McFetridge
- J. Crayton Pruitt Department of Biomedical Engineering, University of Florida United States
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Fastner G, Reitsamer R, Ziegler I, Zehentmayr F, Fussl C, Kopp P, Peintinger F, Greil R, Fischer T, Deutschmann H, Sedlmayer F. IOERT as anticipated tumor bed boost during breast-conserving surgery after neoadjuvant chemotherapy in locally advanced breast cancer--results of a case series after 5-year follow-up. Int J Cancer 2014; 136:1193-201. [PMID: 24995409 DOI: 10.1002/ijc.29064] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Accepted: 06/18/2014] [Indexed: 11/10/2022]
Abstract
To evaluate retrospectively rates of local (LCR) and locoregional tumor control (LRCR) in patients with locally advanced breast cancer (LABC) who were treated with preoperative chemotherapy (primary systemic treatment, PST) followed by breast-conserving surgery (BCS) and either intraoperative radiotherapy with electrons (IOERT) preceding whole-breast irradiation (WBI) (Group 1) or with WBI followed by an external tumor bed boost (electrons or photons) instead of IOERT (Group 2). From 2002 to 2007, 83 patients with clinical Stage II or III breast cancer were enrolled in Group 1 and 26 in Group 2. All patients received PST followed by BCS and axillary lymph node dissection. IOERT boosts were applied by single doses of 9 Gy (90% reference isodose) versus external boosts of 12 Gy (median dose range, 6-16) in 2 Gy/fraction (ICRU). WBI in both groups was performed up to total doses of 51-57 Gy (1.7-1.8 Gy/fraction). The respective median follow-up times for Groups 1 and 2 amount 59 months (range, 3-115) and 67.5 months (range, 13-120). Corresponding 6-year rates for LCR, LRCR, metastasis-free survival, disease-specific survival and overall survival were 98.5, 97.2, 84.7, 89.2 and 86.4% for Group 1 and 88.1, 88.1, 74, 92 and 92% for Group 2, respectively, without any statistical significances. IOERT as boost modality during BCS in LABC after PST shows a trend to be superior in terms of LCR and LRCR in comparison with conventional boosts.
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Affiliation(s)
- Gerd Fastner
- Department of Radiotherapy and Radio-Oncology, Landeskrankenhaus, Paracelsus Medical University, Salzburg, Austria
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Lo ST, Wang YT, Lin SD, Strasser G, Bird JP, Chen YF, Liang CT. Tunable insulator-quantum Hall transition in a weakly interacting two-dimensional electron system. Nanoscale Res Lett 2013; 8:307. [PMID: 23819745 PMCID: PMC3716820 DOI: 10.1186/1556-276x-8-307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 06/26/2013] [Indexed: 06/02/2023]
Abstract
We have performed low-temperature measurements on a gated two-dimensional electron system in which electron-electron (e-e) interactions are insignificant. At low magnetic fields, disorder-driven movement of the crossing of longitudinal and Hall resistivities (ρxx and ρxy) can be observed. Interestingly, by applying different gate voltages, we demonstrate that such a crossing at ρxx ~ ρxy can occur at a magnetic field higher, lower, or equal to the temperature-independent point in ρxx which corresponds to the direct insulator-quantum Hall transition. We explicitly show that ρxx ~ ρxy occurs at the inverse of the classical Drude mobility 1/μD rather than the crossing field corresponding to the insulator-quantum Hall transition. Moreover, we show that the background magnetoresistance can affect the transport properties of our device significantly. Thus, we suggest that great care must be taken when calculating the renormalized mobility caused by e-e interactions.
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Affiliation(s)
- Shun-Tsung Lo
- Graduate Institute of Applied Physics, National Taiwan University, Taipei 106, Taiwan
| | - Yi-Ting Wang
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Sheng-Di Lin
- Department of Electronics Engineering, National Chiao Tung University, Hsinchu 300, Taiwan
| | - Gottfried Strasser
- Institute for Solid State Electronics and Center for Micro- and Nanostructures, Technische Universität Wien, Floragasse 7, 1040, Vienna, Austria
| | - Jonathan P Bird
- Department of Electrical Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260-1920, USA
| | - Yang-Fang Chen
- Graduate Institute of Applied Physics, National Taiwan University, Taipei 106, Taiwan
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
| | - Chi-Te Liang
- Graduate Institute of Applied Physics, National Taiwan University, Taipei 106, Taiwan
- Department of Physics, National Taiwan University, Taipei 106, Taiwan
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Abstract
In this paper, the evolutionary and revolutionary developments of microscopic imaging are overviewed with a perspective on origins. From Alhazen's camera obscura, to Hooke and van Leeuwenhoek's two-dimensional optical micrography, and on to three- and four-dimensional (4D) electron microscopy, these developments over a millennium have transformed humans' scope of visualization. The changes in the length and time scales involved are unimaginable, beginning with the visible shadows of candles at the centimetre and second scales, and ending with invisible atoms with space and time dimensions of sub-nanometre and femtosecond. With these advances it has become possible to determine the structures of matter and to observe their elementary dynamics as they unfold in real time. Such observations provide the means for visualizing materials behaviour and biological function, with the aim of understanding emergent phenomena in complex systems.
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Affiliation(s)
- Ahmed H Zewail
- Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA.
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Gougelet RM, Rea ME, Nicolalde RJ, Geiling JA, Swartz HM. The view from the trenches: part 1-emergency medical response plans and the need for EPR screening. Health Phys 2010; 98:118-27. [PMID: 20065673 PMCID: PMC3982875 DOI: 10.1097/hp.0b013e3181a6de7d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Few natural disasters or intentional acts of war or terrorism have the potential for such severe impact upon a population and infrastructure as the intentional detonation of a nuclear device within a major U.S. city. In stark contrast to other disasters or even a "dirty bomb," hundreds of thousands will be affected and potentially exposed to a clinically significant dose of ionizing radiation. This will result in immediate deaths and injuries and subsequently the development of Acute Radiation Syndrome (ARS). Additionally, millions more who are unlikely to develop ARS will seek medical evaluation and treatment, overwhelming the capacity of an already compromised medical system. In this paper, the authors propose that in vivo electron paramagnetic resonance (EPR) dosimetry be utilized to screen large numbers of potentially exposed victims, and that this screening process be incorporated into the medical-surge framework that is currently being implemented across the nation for other catastrophic public health emergencies. The National Incident Management System (NIMS), the National Response Framework (NRF), the Target Capabilities List (TCL), Homeland Security Presidential Directives (HSPD), as well as additional guidance from multiple federal agencies provide a solid framework for this response. The effective screening of potentially-exposed victims directly following a nuclear attack could decrease the number of patients seeking immediate medical care by greater than 90%.
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Pollock JD, Williams BB, Sidabras JW, Grinberg O, Salikhov I, Lesniewski P, Kmiec M, Swartz HM. Surface loop resonator design for in vivo EPR tooth dosimetry using finite element analysis. Health Phys 2010; 98:339-44. [PMID: 20065703 PMCID: PMC4086293 DOI: 10.1097/hp.0b013e3181a6dd08] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Finite element analysis is used to evaluate and design L-band surface loop resonators for in vivo electron paramagnetic resonance (EPR) tooth dosimetry. This approach appears to be practical and useful for the systematic examination and evaluation of resonator configurations to enhance the precision of dose estimates. The effects of loop positioning in the mouth are examined, and it is shown that the sensitivity to loop position along a row of molars is decreased as the loop is moved away from the teeth.
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Koch HW. Recollections on Sixty Years of NBS Ionizing Radiation Programs for Energetic X Rays and Electrons. J Res Natl Inst Stand Technol 2006; 111:443-60. [PMID: 27274947 PMCID: PMC4655999 DOI: 10.6028/jres.111.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/03/2006] [Indexed: 06/06/2023]
Abstract
These recollections are on ionizing radiation programs at the National Bureau of Standards (NBS) that started in 1928 and ended in 1988 when NBS became the National Institute of Standards and Technology (NIST). The independent Council on Ionizing Radiation Measurements and Standards (CIRMS) was formed in 1992. This article focuses on how measurements and standards for x rays, gamma rays, and electrons with energies above 1 MeV began at NBS and how they progressed. It also suggests how the radiation processors of materials and foods, the medical radiographic and radiological industries, and the radiological protection interests of the government (including homeland security) represented in CIRMS can benefit from NIST programs.
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Mills MD, Fajardo LC, Wilson DL, Daves JL, Spanos WJ. Commissioning of a mobile electron accelerator for intraoperative radiotherapy. J Appl Clin Med Phys 2001; 2:121-30. [PMID: 11602008 PMCID: PMC5726042 DOI: 10.1120/jacmp.v2i3.2605] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2001] [Accepted: 05/18/2001] [Indexed: 11/23/2022] Open
Abstract
Radiation performance characteristics of a dedicated intraoperative accelerator were determined to prepare the unit for clinical use. The linear accelerator uses standing wave X-band technology (wavelength approximately 3 centimeters) in order to minimize the mass of the accelerator. The injector design, smaller accelerator components, and low electron beam currents minimize radiation leakage. The unit may be used in a standard operating room without additional shielding. The mass of the accelerator gantry is 1250 Kg (weight approximately 2750 lbs) and the unit is transportable between operating rooms. Nominal electron energies are 4, 6, 9, and 12 MeV, and operate at selectable dose rates of 2.5 or 10 Gray per minute. D(max) depths in water for a 10 cm applicator are 0.7, 1.3, 1.7, and 2.0 for these energies, respectively. The depths of 80% dose are 1.2, 2.1, 3.1, and 3.9 cm, respectively. Absolute calibration using the American Association of Physicists in Medicine TG-51 protocol was performed for all electron energies using the 10 cm applicator. Applicator sizes ranged from 3 to 10 cm diameter for flat applicators, and 3 to 6 cm diameter for 30 degrees beveled applicators. Output factors were determined for all energies relative to the 10 cm flat applicator. Central axis depth dose profiles and isodose plots were determined for every applicator and energy combination. A quality assurance protocol, performed each day before patient treatment, was developed for output and energy constancy.
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Affiliation(s)
- Michael D. Mills
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
| | - Liliosa C. Fajardo
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
| | - David L. Wilson
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
| | - Jodi L. Daves
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
| | - William J. Spanos
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
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Abstract
A new approach to intraoperative radiotherapy makes use of a mobile electron linear accelerator delivering therapeutic radiation doses in an operating room suite. This unconventional technology has raised questions concerning protection for personnel and the necessity of shielding the adjoining areas. In this study, the leakage and scatter radiation from the mobile electron accelerator is measured and characterized in a series of spherical projections. An analysis is performed to determine the need for shielding or, alternatively, patient-based load restrictions in the operating room. This investigation provides a resource to assess shielding and/or patient load restrictions for any facility performing intraoperative radiotherapy with a similar unit. The data presented indicates that the mobile electron accelerator may be operated in an area with little or no shielding under nominal patient load expectations.
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Affiliation(s)
- Jodi L. Daves
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
| | - Michael D. Mills
- Department of Radiation OncologyUniversity of Louisville529 South Jackson StreetLouisvilleKentucky40202
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Hubbell JH. Survey of Industrial, Agricultural, and Medical Applications of Radiometric Gauging and Process Control. J Res Natl Inst Stand Technol 1990; 95:689-699. [PMID: 28179800 PMCID: PMC4948932 DOI: 10.6028/jres.095.053] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/22/1990] [Indexed: 06/06/2023]
Abstract
Photon and particle radiations (gamma rays, x rays, brems-strahlung, electrons and other charged particles, and neutrons) from radioactive isotopes, x-ray tubes, and accelerators are now widely used in gauging, production control, and other monitoring and metrology devices where avoidance of mechanical contact is desirable. The general principles of radiation gauges, which rely on detection of radiation transmitted by the sample, or on detection of scattered or other secondary radiations produced in the sample, are discussed. Examples of such devices currently used or at least shown to be feasible in industrial, transportation, building, mining, agricultural, medical, and other metrology situations are presented, drawing from a total of 146 selected technical and review paper reference sources here cited.
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Affiliation(s)
- J H Hubbell
- National Institute of Standards and Technology, Gaithersburg, MD 20899
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Phelps AV. The Diffusion of Charged Particles in Collisional Plasmas: Free and Ambipolar Diffusion at Low and Moderate Pressures. J Res Natl Inst Stand Technol 1990; 95:407-431. [PMID: 28179784 PMCID: PMC4922406 DOI: 10.6028/jres.095.035] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/21/1990] [Indexed: 05/22/2023]
Abstract
The interpretation of measurements of the properties of weakly ionized plasmas in terms of diffusion of electrons and ions is reviewed both critically and tutorially. A particular effort is made to tie together various aspects of charged particle diffusion phenomena in quiescent, partially ionized plasmas. The concepts of diffusion length and effective diffusion coefficient and the treatment of partially reflecting boundaries are developed in the limit of the space-charge-free motion of the electrons or ions. A simplified derivation of the screening length for space charge electric fields is followed by a review of the conventional derivation of diffusion in the ambipolar limit. A discussion of the scaling parameters of the ratio of the diffusion length to the screening length and the ratio of the diffusion length to the ion mean-free-path leads to a map used to correlate published models covering the complete range of these parameters. The models of measurements of the diffusion of electrons, several types of positive ions, and negative ions are reviewed. The role of diffusion in the decay of charged particle densities and wall currents during the afterglow of a discharge is then considered. The effects of collapse of the space charge field and of diffusion cooling are reviewed. Finally, the application of the diffusion models to a number of different discharges is discussed.
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Affiliation(s)
- A V Phelps
- Joint Institute for Laboratory Astrophysics, National Institute of Standards and Technology and University of Colorado, Boulder, CO 80309
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