Exposure buildup factors are very important for the calculation of radiation shielding and also applied radiation. We must distinguish the monoenergetic and continuous energy spectrum gamma source in order to calculate the exposure buildup factors. In this study, the exposure buildup factors for two x-ray continuous energy spectra (bremsstrahlung) with 5 and 10 MeV endpoint energies were calculated up to depths of 10 mfp of water. It was observed that there is a large difference between the obtained exposure buildup factors due to the monoenergetic and continuous energy spectrum gamma sources. The calculation results show that the relative differences in 5 MeV energy for 1 mfp to 10 mfp are 114% to 44%, respectively, and also the relative differences in 10 MeV energy for 1 mfp to 10 mfp are 87% to 38%, respectively. Actually, the main purpose of this paper is to illustrate the fact that there is a significant difference between the exposure buildup factors due to the continuous and monoenergetic gamma sources. Therefore, radiation staff must pay more attention to calculating the thickness of radiation shields for continuous energy gamma sources.
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http://dx.doi.org/10.1088/1361-6498/aa9cfa | DOI Listing |
Life Sci Space Res (Amst)
February 2025
Department of Biomedical Engineering, Center for Injury Biomechanics, Wake Forest University School of Medicine. 575 N. Patterson Avenue, Suite 530. Winston-Salem, NC 27101, USA. Electronic address:
Muscle atrophy occurs with extended exposure to microgravity. This study quantified the overall muscle size, lean muscle area and fat infiltration changes pre- to post-flight that occur in the thoracic and lumbar spine with long-duration spaceflight. Pre- and post-flight magnetic resonance imaging (MRI) scans were obtained from 9 crewmembers on long-duration (≥6 months) International Space Station (ISS) missions.
View Article and Find Full Text PDFMaterials (Basel)
January 2025
Innovation in Research & Engineering Solutions (IRES), 1000 Brussels, Belgium.
In modern manufacturing environments, pollution management is critical as exposure to harmful substances can cause serious health issues. This study presents a two-stage computational fluid dynamic (CFD) model to estimate the distribution of pollutants in indoor production spaces. In the first stage, the Reynolds-averaged Navier-Stokes (RANS) method was used to simulate airflow and temperature.
View Article and Find Full Text PDFBiochim Biophys Acta Gen Subj
January 2025
Amity Institute of Biotechnology, Amity University, Kolkata, India. Electronic address:
Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) covers a range of liver conditions marked by the buildup of fat, spanning from simple fatty liver to more advanced stages like metabolic dysfunction-associated steatohepatitis and cirrhosis.
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Int J Pharm
January 2025
Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada. Electronic address:
The objective of this study is to address the unanswered question whether sustained supersaturation generated from amorphous solid dispersions (ASDs) formulated in insoluble hydrogel carriers will result in better bioavailability over that of spring-and-parachute type of dissolution profiles of ASDs formulated in water-soluble carriers. This was achieved by investigating the effects of supersaturation generation rates and doses on the extent of absorption (i.e.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
MOE Key Laboratory of Bio-Intelligent Manufacturing, School of Bioengineering, Dalian University of Technology, Dalian 116024, PR China.
Microalgae-based wastewater treatment could realize simultaneous nutrients recovery and CO sequestration. However, impacts of environmental microplastics (MPs) and antibiotic co-exposure on microalgal growth, nutrients removal, intracellular nitric oxide (NO) accumulation and subsequent nitrous oxide (NO) emission are unclarified, which could greatly offset the CO sequestration benefit. To reveal the potential impacts of environmental concentrations of MPs and antibiotic co-exposure on microalgal greenhouse gas mitigation, this study investigated the effects of representative MPs (PE, PVC, PA), antibiotic sulfamethoxazole (SMX), and nitrite (NO-N) in various combinations on attached Chlorella sorokiniana growth, nutrients removal, anti-oxidative responses, and NO emission originated from intracellular NO build-up.
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