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Zhongyu Wu Zhichao Lin Pamela Mackill Cong Wei John Noonan James Cherniack Deborah Gillis-Landrum 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(3):971-977
Measurement capability and data comparability are essential for emergency response when analytical data from cooperative laboratories
are used for risk assessment and post incident decision making. In this study, the current capability of food emergency response
laboratories for the analysis of 210Po in water was evaluated using a proficiency test scheme in compliance with ISO-43 and ILAC G13 guidelines, which comprises
a test sample preparation and verification protocol and an insightful statistical data evaluation. The results of performance
evaluations on relative bias, value trueness, precision, false positive detection, minimum detection limit, and limit of quantification,
are presented. 相似文献
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Multiphoton microscopy has enabled biologists to collect high-resolution images hundreds of microns into biological tissues, including tissues of living animals. While the depth of imaging exceeds that possible from any other form of light microscopy, multiphoton microscopy is nonetheless generally limited to depths of less than a millimeter. Many of the advantages of multiphoton microscopy for deep tissue imaging accrue from the unique nature of multiphoton fluorescence excitation. However, the quadratic relationship between illumination level and fluorescence excitation makes multiphoton microscopy especially susceptible to factors that degrade the illumination focus. Here we examine the effect of spherical aberration on multiphoton microscopy in fixed kidney tissues and in the kidneys of living animals. We find that spherical aberration, as evaluated from axial asymmetry in the point-spread function, can be corrected by adjustment of the correction collar of a water immersion objective lens. Introducing a compensatory positive spherical aberration into the imaging system decreases the depth-dependence of signal levels in images collected from living animals, increasing signal by up to 50%. 相似文献
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Cao H Lake DE Ferguson JE Chisholm CA Griffin MP Moorman JR 《IEEE transactions on bio-medical engineering》2006,53(1):111-118
Continuous electronic fetal heart rate (FHR) monitoring during labor is motivated by the clinical experience that fetal distress causes loss of FHR variation and the occurrence of decelerations late during uterine contraction. This practice is of uncertain clinical benefit, perhaps because the interpretation is qualitative. We have developed new quantitative measures and analyzed cardiotocograph records from 148 consecutive patients, 44 of whom had at least one "nonreassuring" epoch. In multivariate regression models, measures of deceleration and variability were significantly associated with the obstetrician's diagnosis (receiver operating characteristic area 0.84, p < 0.05). This approach may be useful clinically. 相似文献
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Mathieu Mirjolet Hari Babu Vasili LLuís Lpez‐Conesa Snia Estrad Francesca Peir Jos Santiso Florencio Snchez Pamela Machado Pierluigi Gargiani Manuel Valvidares Josep Fontcuberta 《Advanced functional materials》2019,29(37)
Transparent metallic oxides are pivotal materials in information technology, photovoltaics, or even in architecture. They display the rare combination of metallicity and transparency in the visible range because of weak interband photon absorption and weak screening of free carriers to impinging light. However, the workhorse of current technology, indium tin oxide (ITO), is facing severe limitations and alternative approaches are needed. AMO3 perovskites, M being a nd1 transition metal, and A an alkaline earth, have a genuine metallic character and, in contrast to conventional metals, the electron–electron correlations within the nd1 band enhance the carriers effective mass (m*) and bring the transparency window limit (marked by the plasma frequency, ωp*) down to the infrared. Here, it is shown that epitaxial strain and carrier concentration allow fine tuning of optical properties (ωp*) of SrVO3 films by modulating m* due to strain‐induced selective symmetry breaking of 3d‐t2g(xy, yz, xz) orbitals. Interestingly, the DC electrical properties can be varied by a large extent depending on growth conditions whereas the optical transparency window in the visible is basically preserved. These observations suggest that the harsh conditions required to grow optimal SrVO3 films may not be a bottleneck for their future application. 相似文献
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