The americium-beryllium neutron irradiation facility at the National Nuclear Research Institute (NNRI), Ghana, was re-designed with four 20 Ci sources using Monte Carlo N-Particle (MCNP) code to investigate the maximum amount of flux that is produced by the combined sources. The results were compared with a single source Am-Be irradiation facility. The main objective was to enable us to harness the maximum amount of flux for the optimization of neutron activation analysis and to enable smaller sample sized samples to be irradiated. Using MCNP for the design construction and neutronic performance calculation, it was realized that the single-source Am-Be design produced a thermal neutron flux of (1.8±0.0007)×10(6) n/cm(2)s and the four-source Am-Be design produced a thermal neutron flux of (5.4±0.0007)×10(6) n/cm(2)s which is a factor of 3.5 fold increase compared to the single-source Am-Be design. The criticality effective, k(eff), of the single-source and the four-source Am-Be designs were found to be 0.00115±0.0008 and 0.00143±0.0008, respectively.
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http://dx.doi.org/10.1016/j.apradiso.2014.03.017 | DOI Listing |
Appl Radiat Isot
January 2025
Experimental Nuclear Physics Department, Nuclear Research Centre, Egyptian Atomic Energy Authority, Egypt; Cyclotron Facility, Egyptian Atomic Energy Authority, Egypt.
Neutron and gamma-ray shielding design for a 30Ci (1.11TBq) Am-Be irradiation facility is studied using MCNP5 Monte Carlo simulation code. The study focuses on the optimization of the shielding layers of the previously planned neutron irradiation facility.
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
January 2025
Department of Radiation Oncology, University Medical Centre Freiburg, Robert-Koch Straße 3, 79106, Freiburg, Germany.
Purpose: Prostate-specific membrane-antigen positron emission tomography (PSMA PET) is a promising candidate for non-invasive characterization of prostate cancer (PCa). This study evaluated whether PET with tracers [Ga]Ga-PSMA-11 or [F]PSMA-1007 is capable to depict intratumour heterogeneity of histological PSMA expression.
Methods: Thirty-five patients with biopsy-proven primary PCa without evidence of metastatic disease nor prior interventions were prospectively enrolled.
PLoS One
January 2025
University Department of Life Sciences and Public Health, Università Cattolica del Sacro Cuore, Rome, Italy.
Background: The study of women exposures and child outcomes occurring in the first 1,000 days of life since conception enhances understanding of the relationships between environmental factors, epigenetic changes, and disease development, extending beyond childhood and spanning the entire lifespan. Generation Gemelli is a recently launched case-control study that enrolls mother-newborns pairs in one of the largest university hospitals in Italy, in order to examine the association between maternal environmental exposures and intrauterine growth restriction (IUGR) and the risk of premature birth. The study will also evaluate the association of maternal exposures and the health and growth of infants and children up to 24 months of age.
View Article and Find Full Text PDFGlob Health Action
December 2024
Pediatrics, The University of Vermont, University of Vermont Medical Center, Burlington, VT, USA.
Background: Neonatal and maternal mortality remains high in low- and middle-income countries (LMIC), especially in sub-Saharan Africa. Quality data collection is crucial to understand the magnitude of these problems and to measure the impact of interventions aimed at improving neonatal and maternal mortality. However, data collection in the low-income country setting, especially in rural areas, has been a challenge for researchers, policy makers, and public health officials.
View Article and Find Full Text PDFMed Dosim
January 2025
Medical Technology, Health Information and Research Directorate, Ministry of Health, Jerusalem, Israel.
Uganda's only radiotherapy center is a very busy facility treating about 210 patients daily on three linear accelerators making it sometimes hard to have machine time for pretreatment QAs. This study was aimed at validating an independent calculation software, ClearCalc (ICS) for second checks of the treatment planning system (TPS) calculations. The validation of ICS started with simple phantom test plans consisting of square, irregular, open and wedged fields designed in the TPS and measured in phantoms.
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