Photon detectors utilised for direct thyroid measurements to determine the radioiodine content in the thyroid are normally calibrated using a phantom that mimics the human neck, including the thyroid. However, such measurements are necessarily subject to uncertainty because of the difference between the phantom and the real human subject and also the morphological differences among individuals. In this study, personal voxel phantoms were created from magnetic resonance images of the necks of 24 adult volunteers (15 males and 9 females), and numerical simulations using these phantoms were performed to examine the variation in a conversion factor (131I kBq in the thyroid per μSv h-1) for a conventional NaI(Tl) survey meter among the individuals and also to confirm the suitability of reference Japanese voxel phantoms as a calibration standard for such measurements. As a result, it was found that the conversion factor obtained from the reference Japanese male (female) phantom was 1.29 (1.18) times larger than the average conversion factor for the male (female) subjects, suggesting that the conversion factors of the reference Japanese adult male and female phantoms would generally overestimate the 131I thyroidal contents and that the thyroid volume would be one of the factors influencing the conversion factor. This study also revealed a wide difference in the thyroid volume among individuals, which would be of concern when performing specific dose assessments for heavily exposed persons.
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J Anim Physiol Anim Nutr (Berl)
December 2024
Department of Veterinary Medicine and Animal Sciences, University of Milan, Lodi, Italy.
Food leftovers can be used as alternative feed ingredients for monogastric to replace human-competing feedstuffs, such as cereals, recycle a waste product, reduce the feed-food competition and keep nutrients and energy in the feed-food chain. Among food leftovers, former food products (FFPs) are no more intended for human but still suitable for animal consumption. However, the metabolic impact of FFP has never been investigated.
View Article and Find Full Text PDFBrain Commun
December 2024
Faculty of Science and Medicine, University of Fribourg, Fribourg 1700, Switzerland.
Individuals diagnosed with functional neurological disorder experience abnormal movement, gait, sensory processing or functional seizures, for which research into the pathophysiology identified psychosocial contributing factors as well as promising biomarkers. Recent pilot studies suggested that (epi-)genetic variants may act as vulnerability factors, for example, on the oxytocin pathway. This study set out to explore endogenous oxytocin hormone levels in saliva in a cohort of 59 functional neurological disorder patients and 65 healthy controls comparable in sex and age.
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, P. R. China.
Proton-electron transfer (PET) processes play a pivotal role in numerous electrochemical reactions; yet, effectively harnessing them remains a formidable challenge. Consequently, unveiling the PET pathway is imperative to elucidate the factors influencing the efficiency and selectivity of small molecule electrochemical conversion. In this study, a Zn-NC model catalyst with N and C vacancies was synthesized using a hydriding method to investigate the universal impact of PET on CO electroreduction.
View Article and Find Full Text PDFPlant Sci
December 2024
Shanghai Collaborative Innovation Center of Agri-Seeds, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, China. Electronic address:
In recent years, light red or white strawberries have attracted much attention because of their unusual color, however, the mechanism of strawberry color formation, especially light red strawberry color, is not well understood. By EMS mutagenesis of woodland strawberry (Fragaria vesca), we identified two mutants, rg40 and rg120, with light red fruit and yellow-green petiole, and allelic hybridization and BSA mixed-pool sequencing revealed that the phenotype was caused by mutation in the FvPAL2 protein in the anthocyanin synthesis pathway. Enzyme activity experiments showed that the mutant FvPAL2 protein barely catalyzed the substrate conversion normally, thus blocking anthocyanin synthesis, which in turn led to a decrease in anthocyanin accumulation in fruits and petioles.
View Article and Find Full Text PDFJ Phys Chem Lett
December 2024
School of Chemistry and Chemical Engineering, Anhui Province Key Laboratory of Value-Added Catalytic Conversion and Reaction Engineering, Hefei University of Technology, Hefei 230009, China.
Heterogeneous cobalt phthalocyanine has emerged as a promising molecular catalyst for electrochemical reduction of CO to methanol. Boosting both electrocatalytic durability and selectivity remains a great challenge, which is more difficult with unknown regulation factors for the HER side reaction. Herein, to discover the key to balancing the durability and selectivity, as well as HER regulation, we carried out GC-DFT calculations, based on which dynamic product distribution modeling was conducted to visually present the variation of the product distribution within the applied voltage range.
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