The analysis of the isotopic composition of nuclear or non-nuclear solid materials is performed in a variety of fields, e.g., for quality assurance in the production of nuclear fuels, as signatures in forensics, nuclear safeguards, and non-proliferation control, in material characterization, geology, and archeology. We have investigated the capability of laser ablation (New Wave Research, 213 nm) coupled to time-of-flight (TOF) ICP-MS (GBC OptiMass 8000) as a rapid analytical protocol for multi-isotope screening of nuclear and non-nuclear solid samples. This includes natural and non-natural isotopic compositions for elements including Cu, Zr, Mo, Cd, In, Ba, Ta, W, Re, Pt, Pb, and U, in pure metals, alloys, and glasses. Without correcting for mass bias (mass fractionation), an overall precision and accuracy of about 4% (1 sigma) can be achieved by minimizing the deposited laser power and thus fractionation (mass removal based on thermal properties). The precision and accuracy in combination with literally no or minimized sample preparation enables a rapid isotope screening of solid samples that is of particular interest to support nuclear forensic and safeguard analysis.
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http://dx.doi.org/10.1016/j.jenvrad.2009.07.009 | DOI Listing |
Front Plant Sci
January 2025
College of Agriculture, Shihezi University, Shihezi, China.
Introduction: In order to elucidate the physiological mechanism of post-flowering assimilate transport regulating the formation of yields in arid regions and to provide technological support for further water-saving and high yields in the wheat region in Xinjiang, we conducted a study on the effects of different fertility periods and different degrees of drought and re-watering on the post-flowering dry matter accumulation and transport of spring wheat and the characteristics of grain filling.
Methods: In two spring wheat growing seasons in 2023 and 2024, a split-zone design was used, with the drought-sensitive variety Xinchun 22 (XC22) and drought-tolerant variety Xinchun 6 (XC6) as the main zones and a fully irrigated control during the reproductive period [CK, 75%~80% field capacity (FC)], with mild drought at the tillering stage (T1, 60%~65% FC), moderate drought at the tillering stage (T2, 45%~50% FC), mild drought at the jointing stage (J1, 60%~65% FC), and mild drought at the jointing stage (J2, 45%~50% FC) as the sub-zones.
Results: The dry matter accumulation of the aboveground parts of wheat (stem sheaths, leaves, and spikes), the transfer rate and contribution rate of nutrient organs, the maximum filling rate (V), and the mean filling rate (V) increased significantly after re-watering in the T1 treatment, and decreased with the deepening of the degree of water stress.
Anal Methods
January 2025
National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing, Beijing, 100029, China.
With the increasing demand for energy, nuclear energy has been developing rapidly. The quantitative detection and qualitative identification of uranium (U) are of great significance for the comprehensive and efficient use of U resources and the control of nuclear and radioactive substances. In this study, the detection of U is divided into liquid sample detection, solid sample detection, gas sample detection, and industrial detection from the perspectives of the sample state and detection environment.
View Article and Find Full Text PDFEndokrynol Pol
January 2025
Department of Paediatric Oncology, The Children's Memorial Health Institute, Warsaw, Poland.
The rapid progress made in recent years in thyroid cancer research has necessitated the systematic updating of current clinical recommendations. This update presents the evidence-based management of differentiated thyroid carcinoma (DTC) and medullary thyroid carcinoma in children, including preoperative diagnostics, surgical management, radioiodine therapy in DTC treatment with L-thyroxine, disease monitoring, treatment of advanced disease, and finally, consequences of thyroid cancer treatment. Each recommendation is evaluated regarding its strength (Strength of Recommendation; SoR) and the quality of supporting data (QoE - Quality of Evidence).
View Article and Find Full Text PDFSci Total Environ
January 2025
Laboratorio de Limnología, Unidad de Ecología y Sistemática (UNESIS), Departamento de Biología, Pontificia Universidad Javeriana, Bogotá, Colombia.
In this study, we focused on Lake Tota (Colombia) as a model for investigating the impact of anthropogenic activities on lake productivity. Two sediment cores collected from the two main basins of the lake (Lago Grande and Lago Chico) were dated using alpha spectrometry for Pb. Changes in organic matter, carbon and nitrogen isotope ratios, C:N ratios, diatoms and elemental fractions were examined as indicators of productivity.
View Article and Find Full Text PDFEur J Med Chem
January 2025
Key Laboratory of Radiopharmaceuticals of Ministry of Education, NMPA Key Laboratory for Research and Evaluation of Radiopharmaceuticals (National Medical Products Administration), College of Chemistry, Beijing Normal University, Beijing, 100875, China. Electronic address:
Cyclin-dependent kinase 4/6 (CDK4/6) plays a crucial role in cell cycle regulation, is overexpressed in various cancers and is an important target in the development of radiotracers for tumour imaging. Despite the increasing recognition of CDK4/6 inhibitors in cancer therapy, their application is limited by the lack of suitable biomarkers. Herein, we developed a series of technetium-99m-labelled CDK4/6 radiotracers and utilized a linker optimization strategy to reduce their abdominal uptake and enhance their imaging properties.
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