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Low Energy Particle Accelerators and Laboratories
Published in Vlado Valković, Low Energy Particle Accelerator-Based Technologies and Their Applications, 2022
Of interest is to mention plasma-surface interaction research at the CLASS. The material requirements for plasma-facing components in a nuclear fusion reactor are some of the strictest and most challenging. These materials are simultaneously exposed to extreme heat loads) and particle fluxes (>1024 m−2 s−1) while also undergoing high neutron irradiation (1018 neutrons/m2 s). At CLASS, many of the most important issues in plasma-surface interaction research, such as plasma-driven material erosion and deposition, material transport and irradiation and hydrogenic retention were investigated with the use of a 1.7 MV tandem ion accelerator. IBA was used to investigate and quantify changes in materials due to plasma exposure and ion irradiation was used as a proxy for neutron irradiation to investigate plasma-surface interactions for irradiated materials (Wright et al. 2011).
Physics of Radiation Biology
Published in Kedar N. Prasad, Handbook of RADIOBIOLOGY, 2020
Certain low-mass nuclei may be combined to produce one nucleus with an average binding energy per nucleon greater than that for either of the original nuclei. This process is called nuclear fusion and is accompanied by the release of large amounts of energy. For example:
J.B.S. Haldane (1892–1964)
Published in Krishna Dronamraju, A Century of Geneticists, 2018
Haldane predicted that chemistry will be extremely accurate and the meta-chemistry of short-lived particles will be about as systematic as is classical chemistry in 1964. Nuclear fusion reactions based on the conversion of hydrogen to helium will be practicable on a laboratory scale, but not yet a source of industrial power by A.D. 2000. There will be a few people resident on the moon and Mars, but a voyage to the nearest star would not even be a possibility!
Prolonged effect associated with inflammatory response observed after exposure to low dose of tritium β-rays
Published in International Journal of Radiation Biology, 2020
Yi Quan, Zhaoyi Tan, Yang Yang, Bing Deng, Long Mu
With the development of nuclear technology, nuclear fusion and related technologies play a remarkable role in the ongoing provision of green energy resources (Editorial 2016). As the only radioactive isotope of hydrogen and main fuel of fusion reactor, tritium production and processing capacity will be unprecedented. To explore the hazardous impact of tritium, abundant studies have been performed on radiobiological effects induced by tritium. Based on these data, individual dose limit from tritium exposure has been established by the International Commission on Radiological Protection (ICRP). A radiation weighting factor of 1 for tritium exposure is commonly used, although the value of relative biological effectiveness (RBE) significantly elevates and varies from 1.1 to 5.0 in the situation of chronic exposure with γ-rays as a reference ray (Little and Lambert 2008). In addition, various national standards of tritium concentration in drinking water are used and vary from 100 Bq/L to 76 kBq/L (Guéguen et al. 2018). It reflects there is a lack of sufficient knowledge to recognize the evolution of biological damage produced by tritium exposure and its subsequent evaluation of health risk (Kocher and Hoffman 2011).
Practical applications of DNA genotyping in diagnostic pathology
Published in Expert Review of Molecular Diagnostics, 2019
Hydatidiform mole is a common gestational trophoblastic disease (GTD) which is the result of an abnormal fertilization event that nonetheless implants and proliferates. Two basic categories of moles exist, termed complete and partial mole. Complete mole (CHM) contains a diploid androgenic-only genome and most commonly results from the fertilization of an anucleate ovum with a single sperm, which then undergoes genomic duplication, resulting in a karyotype of 46XX (87–97% of cases) [63,64,87]. In a minority of cases, simultaneous fertilization of an empty ovum by two sperms can occur (3–13%), resulting in a complete mole with a karyotype of either 46XX or 46XY. Regardless of the mechanism, the genomic complement of a complete mole is exclusively paternal. It should be noted that there are rare cases of familial biparental complete moles, with associated mutations of NLRP7 or KHDC3L (ref [88–92]. By contrast, a partial mole (PHM) is the result of the fertilization of a normal haploid ovum with two sperm simultaneously. Alternatively, a haploid ovum may be fertilized by a single sperm, which then undergoes a genomic duplication event prior to nuclear fusion. In either instance, the result is typically a triploid genotype of 69XXY, 69XXX, or less commonly 69XYY.
Proteomic approaches for cancer epigenetics research
Published in Expert Review of Proteomics, 2019
Dylan M. Marchione, Benjamin A. Garcia, John Wojcik
In 1998, Slany et al. reported that the transforming capacity of the canonical MLL-ENL fusions required both the DNA-binding activity of MLL and the transcriptional effector properties of ENL [98]. This finding plus the observation that most MLL fusion partners are involved in transcriptional elongation, led to the hypothesis that ‘a unifying mechanism for the activation of MLL by nuclear fusion partners is the gain of transcriptional effector properties […]’ and ‘conversion of MLL to a constitutive transcriptional effector may be sufficient to provide a gain of function that promotes leukemogenesis in vivo’ [99]. In a follow-up study, Mueller and colleagues expressed FLAG-tagged ENL in HEK293 (human embryonic kidney) cells, and then performed IP-MS to identify interaction partners [100]. The list of candidate partners – collectively named EAPs (ENL-associated proteins) – comprised 15 proteins, many of which were previously shown to interact with ENL or its homolog AF9 in two-hybrid screens. These included the H3K79 methyltransferase DOT1L, the RNA polymerase II C-terminal domain kinase P-TEFb, and the AF4-family transcription factors AF4, LAF4, and AF5q31. Notably, many of the identified interacting proteins can also substitute for ENL as an oncogenic MLL fusion partner, suggesting that the fusion partners are modular, and interchangeably fuse MLL to the complex.