A miniature four-chamber alpha track detector was developed that measures both (222)Rn (radon) and (220)Rn (thoron), in duplicate. Using this detector and the previous long-term measurements of the (220)Rn decay products (212)Pb, and (212)Bi, an equilibrium factor, F(eq), is derived for both outdoor and indoor (220)Rn environments (0.004±0.001 outdoors and 0.04±0.01 indoors). The lung airway dose can then be calculated from a dose factor from UNSCEAR that requires the equilibrium equivalent thoron concentration (EEC), i.e. the product of F(eq) and the (220)Rn gas concentration. The lung dose from thoron in domestic or occupational surveys is often overlooked. The values of F(eq) for thoron in several published studies are in general agreement with the values reported here. Thus, a long-term alpha track measurement of thoron multiplied by an appropriate indoor or outdoor equilibrium factor yields the EEC, which can be used to assess bronchial lung dose.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1093/rpd/ncq228 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Polymorphisms and dental age in non-syndromic cleft lip and palate: a cross-sectional study.
BMC Pediatr
January 2025
Department of Orthodontics, University Hospital Bonn, Medical Faculty, Welschnonnenstr. 17, 53111, Bonn, Germany.
Background: Children with non-syndromic cleft lip with or without palate (CL ± P) may present alterations in dental development. The purpose of this cross-sectional study was to compare the dental age (DA) between children with and without CL ± P, and whether single nucleotide polymorphisms (SNPs) in genes encoding growth factors are associated with DA variations.
Methods: Children aged between 5 and 14 years with and without CL ± P were recruited to participate in this study.
Transdermal patch based on pressure-sensitive adhesive: the importance of adhesion for efficient drug delivery.
Expert Opin Drug Deliv
January 2025
School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, Liaoning, China.
Introduction: Transdermal patches offer a unique advantage by providing extended therapeutic benefits while maintaining stable plasma drug concentration. The efficacy and safety of patches depend significantly on their ability to adhere to the skin, a feature influenced by various external and internal factors.
Areas Covered: The review primarily focuses on the fundamental aspects of adhesion in transdermal patches, including basic information about the skin, the underlying principles of adhesion, drug delivery, and adhesion characteristics of pressure sensitive adhesives (PSAs), adhesion issues, impact factors, strategies to improve patch adhesion, and relevant molecular mechanisms.
Optoelectronic tweezers (OET) offer a versatile, programmable, and contactless method for manipulating microscale objects. While factors like AC voltage and light intensity have been extensively studied, the role of light pattern curvature in the performance of OET manipulation remains underexplored. This study investigates how the curvature of light patterns affects the movement of polystyrene microparticles under negative dielectrophoretic (DEP) forces in an OET system.
View Article and Find Full Text PDFSeparation effectiveness of ideal ion exchange membranes: Application of the Gibbs-Donnan theory.
PLoS One
January 2025
Nalecz Institute of Biocybernetics and Biomedical Engineering, Polish Academy of Sciences, Warsaw, Poland.
Ion exchange membranes (IEMs) are permselective membranes that, in principle, only allow the flow of ions with a specific charge sign, opposite to that of the fixed membrane ionic groups (counter-ions). This charge-based selectivity, like the size-based selectivity of classic semipermeable membranes, leads to an uneven distribution of permeating ions on the two sides of the membrane, which allows for ion separation or recovery in various processes in industry or environmental protection. Here, we apply the principles of mass balance, charge neutrality, and equality of electrochemical potentials in the state of thermodynamic equilibrium to provide a simple method for estimating the Gibbs-Donnan factors and the equilibrium concentrations of permeating ions in two compartments separated by an ideal IEM, i.
View Article and Find Full Text PDFRegulatory cellular and molecular networks in the bone microenvironment during aging.
Life Med
June 2024
Department of Orthopedic Surgery, Xijing Hospital, Airforce Medical University, Xi'an 710032, China.
Age-induced abnormalities in bone metabolism disrupt the equilibrium between bone resorption and formation. This largely stems from disturbances in bone homeostasis, in which signaling pathways exert a significant regulatory influence. Aging compromises the functionality of the bone marrow mesenchymal stem cells (BMSCs), ultimately resulting in tissue dysfunction and pathological aging.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!