Radionuclide Concentrations in Soils lution-Processed Organic Solar Cells
Michael Pöschl, Leo M. L. Nollet in Radionuclide Concentrations in Food and the Environment, 2006
The apparent migration velocity, v (in cm/year), and the apparent dispersion coefficient, D (in cm2/year), were selected as migration parameters. These parameters were evaluated by fitting the 137Cs profiles to a Gauss-type function. The apparent migration velocity ranged from 0.14 to 0.22 cm/year and the apparent dispersion coefficient ranged from 0.04 to 0.07 cm2/year. The uncertainties of the fitted parameters ranged from less than 1% to 10% for v and less than 5% to 35% for D. This study was extended to other fallout radionuclides and migration parameters. There are essentially three mobility groups. Strontium, cesium, cobalt, antimony, niobium, and plutonium show low mobility, americium is more mobile, and europium is the most mobile of all the investigated elements. This is explained by the different interactions between soils (sorption) and elements.
Beta and Alpha Particle Autoradiography
Michael Ljungberg in Handbook of Nuclear Medicine and Molecular Imaging for Physicists, 2022
The phosphor storage plates are perhaps the most common of autoradiography systems currently found in modern radionuclide imaging labs. It has the benefits of higher dynamic range, reusability, and digital readout over film and was quickly adapted for use with autoradiography [24]. The imaging plates consist of barium fluorohalide crystals doped with europium on the surface, covered by a protective layer unless specially designed for very low (e.g., 3H) energy electrons that cannot penetrate such a layer. Ionizing radiation that interacts with the crystals will further ionize the europium, taking it from Eu2+ to Eu3+. The electrons leaving the europium will be trapped in fluorohalide vacancies [7]. The entrapment of the electrons is a metastable state with a limited half-life, which will limit the usability of phosphor storage screens for very low activity samples where new ionizations cannot generate new Eu3+ fast enough to compensate for the recombination of electrons and ions [24]. If the activity in the measured sample is over this limit, however, it will generate more and more trapped electrons and europium ions the more ionizing radiation interacts with the active layer. The length of this exposure step will have to be individually decided for each study depending on radionuclide and activity in the measured samples.
Digital Receptors
Christopher M. Hayre, William A. S. Cox in General Radiography, 2020
The addition of europium changes the structure of the crystal. Consequently, the electrons actually become trapped within the halide portion of the phosphor layer due to defects in the lattice that are present in the crystal as a result of the addition of europium (Fujifilm Imaging Plate Manual, n.d.; Leblans et al., 2011). Subsequently, these defects become traps for the electrons that are leaving the conduction band. The process of electron release (ionization) and capture (energy traps) happens numerous times and is proportional to the X-ray exposure received. This contributes to the formation of the latent image.
Molecular docking study on europium nanoparticles and mussel adhesive protein for effective detection of latent fingerprints
Published in Biomarkers, 2023
T. R. Poorani, C. Ramya, Ramya Manohar
The Europium element whose atomic symbol is Eu and atomic number is 63, is present in Block F, Group 3, Period 6 of the periodic table. Its atomic radius is around 151.964. Each europium shell is filled with the number of electrons of about 2, 8, 18, 25, 8, 2 with an electronic configuration of [Xe]4f76s2. This europium metal belongs to the lanthanide or rare earth series which has an atomic radius of about 180 pm and its Van der Waals radius was about 233 pm. This metal looks like a silvery white and found as a free element in natural environment. Europium nanoparticles (EuNp) also known as nanopowder or nanodots looks like a black spherical particle with higher surface area and are around 10 − 45 nm with the specific surface area (SSA) of about 30 − 50 m2/g. These nanoparticles were also available with the average particle size of 75 − 100 nm. Once these europium nanoparticles were surface functionalised, these can be easily adsorbed onto the surface interface by chemically interacting polymers. The chemical structure of the europium nanoparticles synthesised and its interaction with Mussel adhesive protein amino acid is represented in the Figure 1.
A functional antibody cross-reactive to both human and murine cytotoxic T-lymphocyte-associated protein 4 via binding to an N-glycosylation epitope
Published in mAbs, 2020
Dong Li, Jing Li, Huanyu Chu, Zhuozhi Wang
The ADCC assay was performed based on DELFIA® EuTDA Cytotoxicity Reagents (PerkinElmer-AD0116). Briefly, human CTLA4-expressing 293F cells were added to 96-well plates at 1 × 104 per well, and then various concentrations of antibodies pre-incubated with 5 × 105 peripheral blood mononuclear cells, collected from healthy donors after they provided informed consent, were added to the plates. The plates were kept at 37°C in a 5% CO2 incubator for 4 h. Lysis of the target cells was determined by DELFIA Europium Solution. The europium and the ligand form a highly fluorescent and stable chelate (EuTDA), and then the signal was read using SpectraMax® M5e. In ADCP assay, human monocytes were isolated using Human Monocyte Enrichment Kit (Miltenyi Biotec-130-050-201) and incubated with 100 ng/mL recombinant human M-CSF (R&D-216-MC) for the differentiation of macrophage. Then, macrophage cells were mixed with carboxyfluorescein succinimidyl ester-dyed engineered human CTLA-4 expressing 293F cells at 1:1 ratio; then, various concentrations of antibodies were added and cultured with cells at 37°C in a 5% CO2 incubator for 3 h. After wash, allophycocyanin-labeled anti-human CD14 antibody (1:100, eBioscience-17-0149-42) was added for detection. The phagocytosis rate of antibodies to the cells was tested by flow cytometry.
High-throughput optofluidic screening of single B cells identifies novel cross-reactive antibodies as inhibitors of uPAR with antibody-dependent effector functions
Published in mAbs, 2023
André Luiz Lourenço, Shih-Wei Chuo, Markus F. Bohn, Byron Hann, Shireen Khan, Neha Yevalekar, Nitin Patel, Teddy Yang, Lina Xu, Dandan Lv, Robert Drakas, Sarah Lively, Charles S. Craik
ADCC on MDA-MB-231 by NK cells was detected by DELFIA® EuTDA Cytotoxicity Reagents (Perkinelmer). Briefly, MDA-MB-231 cells were harvested and labeled by incubation with 2 μL/mL of the fluorescence-enhancing ligand (ParkinElmerDELFIA® BATDA Labeling Reagent) for 20 min at 37°C. After the diffusion of BATDA into the cells, it was hydrolyzed and converted to 2,2‘:6’,2“-terpyridine-6,6”-dicarboxylic acid (TDA) by cytosolic acetyl esterase. Since TDA is a non-cell permeable hydrophobic ligand, it can be trapped inside the live target cells. The solution was centrifuged, and cells were washed three times with PBS. The labeled cells were reconstituted in RPMI 1640 media without phenol red and then seeded to a 96-well U-bottom sterile microplate (100 μL, 1 × 104 cells/well). Next, 50 μL of a serial dilution of each antibody was added to the assay plate and incubated at 37°C for 5–10 min. Separately, NK-92 CD16a 176 V effector cells were harvested and concentrated to approximately 1.2 × 106 cells/mL before the addition of 50 μL to the assay plate resulting in an effector to target cell ratio of 6:1 in each well. The plate containing the antibodies, target, and effector cells was then incubated for 4 hr at 37°C and 5% CO2. After the incubation, the plate was centrifuged for 5 min at 400 RCF, and 25 μL of the supernatant was transferred to a flat-bottom detection plate. Finally, 200 μL of Europium solution (PerkinElmer, DELFIA® Eu-Solution) was added to each well, and the plate was incubated for 15 min at room temperature to allow the formation of a highly fluorescent stable-chelate (Eu-TDA). The resulting fluorescent signal was obtained in a time-resolved fluorimeter within 5 hr. The background death control was determined by diluting target cells with media, and the maximum death control was determined by incubating cells with 10 µL of lysis buffer (1% Triton X-100) for 30 min prior to centrifuging the plate.
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