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For missions beyond low Earth orbit to the moon or Mars, space explorers will encounter a complex radiation field composed of various ion species with a broad range of energies. Such missions pose significant radiation protection challenges that need to be solved in order to minimize exposures and associated health risks. An innovative galactic cosmic ray simulator (GCRsim) was recently developed at the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL). The GCRsim technology is intended to represent major components of the space radiation environment in a ground analog laboratory setting where it can be used to improve understanding of biological risks and serve as a testbed for countermeasure development and validation. The current GCRsim consists of 33 energetic ion beams that collectively simulate the primary and secondary GCR field encountered by humans in space over the broad range of particle types, energies, and linear energy transfer (LET) of interest to health effects. A virtual workshop was held in December 2020 to assess the status of the NASA baseline GCRsim. Workshop attendees examined various aspects of simulator design, with a particular emphasis on beam selection strategies. Experimental results, modeling approaches, areas of consensus, and questions of concern were also discussed in detail. This report includes a summary of the GCRsim workshop and a description of the current status of the GCRsim. This information is important for future advancements and applications in space radiobiology.

Accurate characterization of space radiation exposure is critical to assess and communicate multiple health risks for crewmembers participating in future exploration missions. A combination of models and on-board instruments are utilized to meet this requirement. In this work, computational models are evaluated against spaceflight measurements taken within the International Space Station, the Orion spacecraft, the BioSentinel CubeSat, and on the Martian surface. All calculations and measurements cover the exact same time period defined by the Artemis-I mission, and all model calculations were performed blind—without prior knowledge of the measurements. The models are shown to accurately characterize the absorbed dose-rate in highly complex and diverse shielding configurations in locations from Earth to Mars. [ABSTRACT FROM AUTHOR]

Radiation research is a multidisciplinary field, and among its many branches, mathematical and computational modelers have played a significant role in advancing boundaries of knowledge. A fundamental contribution is modelling cellular response to ionizing radiation as that is the key to not only understanding how radiation can kill cancer cells, but also cause cancer and other health issues. The invention of microdosimetry in the 1950s by Harold Rossi paved the way for brilliant scientists to study the mechanism of radiation at cellular and sub-cellular scales. This paper reviews some snippets of ingenious mathematical and computational models published in microdosimetry symposium proceedings and publications of the radiation research community. Among these are simulations of radiation tracks at atomic and molecular levels using Monte Carlo methods, models of cell survival, quantification of the amount of energy required to create a single strand break, and models of DNA-damage-repair. These models can broadly be categorized into mechanistic, semi-mechanistic, and phenomenological approaches, and this review seeks to provide historical context of their development. We salute pioneers of the field and great teachers who supported and educated the younger members of the community and showed them how to build upon their work. [ABSTRACT FROM AUTHOR]

Purpose: High energetic carbon (C‐) ion beams undergo nuclear interactions with tissue, producing secondary nuclear fragments. Thus, at depth, C‐ion beams are composed of a mixture of different particles with different linear energy transfer (LET) values. We developed a technique to enable isolation of DNA damage response (DDR) in mixed radiation fields using beam line microscopy coupled with fluorescence nuclear track detectors (FNTDs). Methods: We imaged live cells on a coverslip made of FNTDs right after C‐ion, proton or photon irradiation using an in‐house built confocal microscope placed in the beam path. We used the FNTD to link track traversals with DNA damage and separated DNA damage induced by primary particles from fragments. Results: We were able to spatially link physical parameters of radiation tracks to DDR in live cells to investigate spatiotemporal DDR in multi‐ion radiation fields in real time, which was previously not possible. We demonstrated that the response of lesions produced by the high‐LET primary particles associates most strongly with cell death in a multi‐LET radiation field, and that this association is not seen when analyzing radiation induced foci in aggregate without primary/fragment classification. Conclusions: We report a new method that uses confocal microscopy in combination with FNTDs to provide submicrometer spatial‐resolution measurements of radiation tracks in live cells. Our method facilitates expansion of the radiation‐induced DDR research because it can be used in any particle beam line including particle therapy beam lines. Category: Biological Physics and Response Prediction. [ABSTRACT FROM AUTHOR]

Real time ultrasound imaging is one of the many ways to clinically evaluate the anatomical and functional condition of female pelvic floor in patients with urinary incontinence. Reflex arc testing of the displacement of uro-gynecological structures during imaging provides a non-invasive way of visualizing their motility. The response from such tests invariably contains a very large amount of visual information, which is not readily captured and assimilated by the observer because it occurs so fast. For this reason only a portion of available information is retained, typically the beginning end ending frame of the image is preserved. Using video motion tracking, parameters were identified to define important biomechanical and temporal relationships. We conclude that new and clinically significant amount of original information about the female pelvic floor can be obtained through the proposed analysis of visualizations. [ABSTRACT FROM AUTHOR]

Real time ultrasound imaging is one of the many ways to clinically evaluate the anatomical and functional condition of female pelvic floor in patients with urinary incontinence. Reflex arc testing of the displacement of uro-gynecological structures during imaging provides a non-invasive way of visualizing their motility. The response from such tests invariably contains a very large amount of visual information, which is not readily captured and assimilated by the observer because it occurs so fast. For this reason only a portion of available information is retained, typically the beginning end ending frame of the image is preserved. Using video motion tracking, parameters were identified to define important biomechanical and temporal relationships. We conclude that new and clinically significant amount of original information about the female pelvic floor can be obtained through the proposed analysis of visualizations.